1// SPDX-License-Identifier: GPL-2.0-or-later
2/* Low-level parallel port routines for built-in port on SGI IP32
3 *
4 * Author: Arnaud Giersch <arnaud.giersch@free.fr>
5 *
6 * Based on parport_pc.c by
7 *	Phil Blundell, Tim Waugh, Jose Renau, David Campbell,
8 *	Andrea Arcangeli, et al.
9 *
10 * Thanks to Ilya A. Volynets-Evenbakh for his help.
11 *
12 * Copyright (C) 2005, 2006 Arnaud Giersch.
13 */
14
15/* Current status:
16 *
17 *	Basic SPP and PS2 modes are supported.
18 *	Support for parallel port IRQ is present.
19 *	Hardware SPP (a.k.a. compatibility), EPP, and ECP modes are
20 *	supported.
21 *	SPP/ECP FIFO can be driven in PIO or DMA mode.  PIO mode can work with
22 *	or without interrupt support.
23 *
24 *	Hardware ECP mode is not fully implemented (ecp_read_data and
25 *	ecp_write_addr are actually missing).
26 *
27 * To do:
28 *
29 *	Fully implement ECP mode.
30 *	EPP and ECP mode need to be tested.  I currently do not own any
31 *	peripheral supporting these extended mode, and cannot test them.
32 *	If DMA mode works well, decide if support for PIO FIFO modes should be
33 *	dropped.
34 *	Use the io{read,write} family functions when they become available in
35 *	the linux-mips.org tree.  Note: the MIPS specific functions readsb()
36 *	and writesb() are to be translated by ioread8_rep() and iowrite8_rep()
37 *	respectively.
38 */
39
40/* The built-in parallel port on the SGI 02 workstation (a.k.a. IP32) is an
41 * IEEE 1284 parallel port driven by a Texas Instrument TL16PIR552PH chip[1].
42 * This chip supports SPP, bidirectional, EPP and ECP modes.  It has a 16 byte
43 * FIFO buffer and supports DMA transfers.
44 *
45 * [1] http://focus.ti.com/docs/prod/folders/print/tl16pir552.html
46 *
47 * Theoretically, we could simply use the parport_pc module.  It is however
48 * not so simple.  The parport_pc code assumes that the parallel port
49 * registers are port-mapped.  On the O2, they are memory-mapped.
50 * Furthermore, each register is replicated on 256 consecutive addresses (as
51 * it is for the built-in serial ports on the same chip).
52 */
53
54/*--- Some configuration defines ---------------------------------------*/
55
56/* DEBUG_PARPORT_IP32
57 *	0	disable debug
58 *	1	standard level: pr_debug1 is enabled
59 *	2	parport_ip32_dump_state is enabled
60 *	>=3	verbose level: pr_debug is enabled
61 */
62#if !defined(DEBUG_PARPORT_IP32)
63#	define DEBUG_PARPORT_IP32  0	/* 0 (disabled) for production */
64#endif
65
66/*----------------------------------------------------------------------*/
67
68/* Setup DEBUG macros.  This is done before any includes, just in case we
69 * activate pr_debug() with DEBUG_PARPORT_IP32 >= 3.
70 */
71#if DEBUG_PARPORT_IP32 == 1
72#	warning DEBUG_PARPORT_IP32 == 1
73#elif DEBUG_PARPORT_IP32 == 2
74#	warning DEBUG_PARPORT_IP32 == 2
75#elif DEBUG_PARPORT_IP32 >= 3
76#	warning DEBUG_PARPORT_IP32 >= 3
77#	if !defined(DEBUG)
78#		define DEBUG /* enable pr_debug() in kernel.h */
79#	endif
80#endif
81
82#include <linux/completion.h>
83#include <linux/delay.h>
84#include <linux/dma-mapping.h>
85#include <linux/err.h>
86#include <linux/init.h>
87#include <linux/interrupt.h>
88#include <linux/jiffies.h>
89#include <linux/kernel.h>
90#include <linux/module.h>
91#include <linux/parport.h>
92#include <linux/sched/signal.h>
93#include <linux/slab.h>
94#include <linux/spinlock.h>
95#include <linux/stddef.h>
96#include <linux/types.h>
97#include <asm/io.h>
98#include <asm/ip32/ip32_ints.h>
99#include <asm/ip32/mace.h>
100
101/*--- Global variables -------------------------------------------------*/
102
103/* Verbose probing on by default for debugging. */
104#if DEBUG_PARPORT_IP32 >= 1
105#	define DEFAULT_VERBOSE_PROBING	1
106#else
107#	define DEFAULT_VERBOSE_PROBING	0
108#endif
109
110/* Default prefix for printk */
111#define PPIP32 "parport_ip32: "
112
113/*
114 * These are the module parameters:
115 * @features:		bit mask of features to enable/disable
116 *			(all enabled by default)
117 * @verbose_probing:	log chit-chat during initialization
118 */
119#define PARPORT_IP32_ENABLE_IRQ	(1U << 0)
120#define PARPORT_IP32_ENABLE_DMA	(1U << 1)
121#define PARPORT_IP32_ENABLE_SPP	(1U << 2)
122#define PARPORT_IP32_ENABLE_EPP	(1U << 3)
123#define PARPORT_IP32_ENABLE_ECP	(1U << 4)
124static unsigned int features =	~0U;
125static bool verbose_probing =	DEFAULT_VERBOSE_PROBING;
126
127/* We do not support more than one port. */
128static struct parport *this_port;
129
130/* Timing constants for FIFO modes.  */
131#define FIFO_NFAULT_TIMEOUT	100	/* milliseconds */
132#define FIFO_POLLING_INTERVAL	50	/* microseconds */
133
134/*--- I/O register definitions -----------------------------------------*/
135
136/**
137 * struct parport_ip32_regs - virtual addresses of parallel port registers
138 * @data:	Data Register
139 * @dsr:	Device Status Register
140 * @dcr:	Device Control Register
141 * @eppAddr:	EPP Address Register
142 * @eppData0:	EPP Data Register 0
143 * @eppData1:	EPP Data Register 1
144 * @eppData2:	EPP Data Register 2
145 * @eppData3:	EPP Data Register 3
146 * @ecpAFifo:	ECP Address FIFO
147 * @fifo:	General FIFO register.  The same address is used for:
148 *		- cFifo, the Parallel Port DATA FIFO
149 *		- ecpDFifo, the ECP Data FIFO
150 *		- tFifo, the ECP Test FIFO
151 * @cnfgA:	Configuration Register A
152 * @cnfgB:	Configuration Register B
153 * @ecr:	Extended Control Register
154 */
155struct parport_ip32_regs {
156	void __iomem *data;
157	void __iomem *dsr;
158	void __iomem *dcr;
159	void __iomem *eppAddr;
160	void __iomem *eppData0;
161	void __iomem *eppData1;
162	void __iomem *eppData2;
163	void __iomem *eppData3;
164	void __iomem *ecpAFifo;
165	void __iomem *fifo;
166	void __iomem *cnfgA;
167	void __iomem *cnfgB;
168	void __iomem *ecr;
169};
170
171/* Device Status Register */
172#define DSR_nBUSY		(1U << 7)	/* PARPORT_STATUS_BUSY */
173#define DSR_nACK		(1U << 6)	/* PARPORT_STATUS_ACK */
174#define DSR_PERROR		(1U << 5)	/* PARPORT_STATUS_PAPEROUT */
175#define DSR_SELECT		(1U << 4)	/* PARPORT_STATUS_SELECT */
176#define DSR_nFAULT		(1U << 3)	/* PARPORT_STATUS_ERROR */
177#define DSR_nPRINT		(1U << 2)	/* specific to TL16PIR552 */
178/* #define DSR_reserved		(1U << 1) */
179#define DSR_TIMEOUT		(1U << 0)	/* EPP timeout */
180
181/* Device Control Register */
182/* #define DCR_reserved		(1U << 7) | (1U <<  6) */
183#define DCR_DIR			(1U << 5)	/* direction */
184#define DCR_IRQ			(1U << 4)	/* interrupt on nAck */
185#define DCR_SELECT		(1U << 3)	/* PARPORT_CONTROL_SELECT */
186#define DCR_nINIT		(1U << 2)	/* PARPORT_CONTROL_INIT */
187#define DCR_AUTOFD		(1U << 1)	/* PARPORT_CONTROL_AUTOFD */
188#define DCR_STROBE		(1U << 0)	/* PARPORT_CONTROL_STROBE */
189
190/* ECP Configuration Register A */
191#define CNFGA_IRQ		(1U << 7)
192#define CNFGA_ID_MASK		((1U << 6) | (1U << 5) | (1U << 4))
193#define CNFGA_ID_SHIFT		4
194#define CNFGA_ID_16		(00U << CNFGA_ID_SHIFT)
195#define CNFGA_ID_8		(01U << CNFGA_ID_SHIFT)
196#define CNFGA_ID_32		(02U << CNFGA_ID_SHIFT)
197/* #define CNFGA_reserved	(1U << 3) */
198#define CNFGA_nBYTEINTRANS	(1U << 2)
199#define CNFGA_PWORDLEFT		((1U << 1) | (1U << 0))
200
201/* ECP Configuration Register B */
202#define CNFGB_COMPRESS		(1U << 7)
203#define CNFGB_INTRVAL		(1U << 6)
204#define CNFGB_IRQ_MASK		((1U << 5) | (1U << 4) | (1U << 3))
205#define CNFGB_IRQ_SHIFT		3
206#define CNFGB_DMA_MASK		((1U << 2) | (1U << 1) | (1U << 0))
207#define CNFGB_DMA_SHIFT		0
208
209/* Extended Control Register */
210#define ECR_MODE_MASK		((1U << 7) | (1U << 6) | (1U << 5))
211#define ECR_MODE_SHIFT		5
212#define ECR_MODE_SPP		(00U << ECR_MODE_SHIFT)
213#define ECR_MODE_PS2		(01U << ECR_MODE_SHIFT)
214#define ECR_MODE_PPF		(02U << ECR_MODE_SHIFT)
215#define ECR_MODE_ECP		(03U << ECR_MODE_SHIFT)
216#define ECR_MODE_EPP		(04U << ECR_MODE_SHIFT)
217/* #define ECR_MODE_reserved	(05U << ECR_MODE_SHIFT) */
218#define ECR_MODE_TST		(06U << ECR_MODE_SHIFT)
219#define ECR_MODE_CFG		(07U << ECR_MODE_SHIFT)
220#define ECR_nERRINTR		(1U << 4)
221#define ECR_DMAEN		(1U << 3)
222#define ECR_SERVINTR		(1U << 2)
223#define ECR_F_FULL		(1U << 1)
224#define ECR_F_EMPTY		(1U << 0)
225
226/*--- Private data -----------------------------------------------------*/
227
228/**
229 * enum parport_ip32_irq_mode - operation mode of interrupt handler
230 * @PARPORT_IP32_IRQ_FWD:	forward interrupt to the upper parport layer
231 * @PARPORT_IP32_IRQ_HERE:	interrupt is handled locally
232 */
233enum parport_ip32_irq_mode { PARPORT_IP32_IRQ_FWD, PARPORT_IP32_IRQ_HERE };
234
235/**
236 * struct parport_ip32_private - private stuff for &struct parport
237 * @regs:		register addresses
238 * @dcr_cache:		cached contents of DCR
239 * @dcr_writable:	bit mask of writable DCR bits
240 * @pword:		number of bytes per PWord
241 * @fifo_depth:		number of PWords that FIFO will hold
242 * @readIntrThreshold:	minimum number of PWords we can read
243 *			if we get an interrupt
244 * @writeIntrThreshold:	minimum number of PWords we can write
245 *			if we get an interrupt
246 * @irq_mode:		operation mode of interrupt handler for this port
247 * @irq_complete:	mutex used to wait for an interrupt to occur
248 */
249struct parport_ip32_private {
250	struct parport_ip32_regs	regs;
251	unsigned int			dcr_cache;
252	unsigned int			dcr_writable;
253	unsigned int			pword;
254	unsigned int			fifo_depth;
255	unsigned int			readIntrThreshold;
256	unsigned int			writeIntrThreshold;
257	enum parport_ip32_irq_mode	irq_mode;
258	struct completion		irq_complete;
259};
260
261/*--- Debug code -------------------------------------------------------*/
262
263/*
264 * pr_debug1 - print debug messages
265 *
266 * This is like pr_debug(), but is defined for %DEBUG_PARPORT_IP32 >= 1
267 */
268#if DEBUG_PARPORT_IP32 >= 1
269#	define pr_debug1(...)	printk(KERN_DEBUG __VA_ARGS__)
270#else /* DEBUG_PARPORT_IP32 < 1 */
271#	define pr_debug1(...)	do { } while (0)
272#endif
273
274/*
275 * pr_trace, pr_trace1 - trace function calls
276 * @p:		pointer to &struct parport
277 * @fmt:	printk format string
278 * @...:	parameters for format string
279 *
280 * Macros used to trace function calls.  The given string is formatted after
281 * function name.  pr_trace() uses pr_debug(), and pr_trace1() uses
282 * pr_debug1().  __pr_trace() is the low-level macro and is not to be used
283 * directly.
284 */
285#define __pr_trace(pr, p, fmt, ...)					\
286	pr("%s: %s" fmt "\n",						\
287	   ({ const struct parport *__p = (p);				\
288		   __p ? __p->name : "parport_ip32"; }),		\
289	   __func__ , ##__VA_ARGS__)
290#define pr_trace(p, fmt, ...)	__pr_trace(pr_debug, p, fmt , ##__VA_ARGS__)
291#define pr_trace1(p, fmt, ...)	__pr_trace(pr_debug1, p, fmt , ##__VA_ARGS__)
292
293/*
294 * __pr_probe, pr_probe - print message if @verbose_probing is true
295 * @p:		pointer to &struct parport
296 * @fmt:	printk format string
297 * @...:	parameters for format string
298 *
299 * For new lines, use pr_probe().  Use __pr_probe() for continued lines.
300 */
301#define __pr_probe(...)							\
302	do { if (verbose_probing) printk(__VA_ARGS__); } while (0)
303#define pr_probe(p, fmt, ...)						\
304	__pr_probe(KERN_INFO PPIP32 "0x%lx: " fmt, (p)->base , ##__VA_ARGS__)
305
306/*
307 * parport_ip32_dump_state - print register status of parport
308 * @p:		pointer to &struct parport
309 * @str:	string to add in message
310 * @show_ecp_config:	shall we dump ECP configuration registers too?
311 *
312 * This function is only here for debugging purpose, and should be used with
313 * care.  Reading the parallel port registers may have undesired side effects.
314 * Especially if @show_ecp_config is true, the parallel port is resetted.
315 * This function is only defined if %DEBUG_PARPORT_IP32 >= 2.
316 */
317#if DEBUG_PARPORT_IP32 >= 2
318static void parport_ip32_dump_state(struct parport *p, char *str,
319				    unsigned int show_ecp_config)
320{
321	struct parport_ip32_private * const priv = p->physport->private_data;
322	unsigned int i;
323
324	printk(KERN_DEBUG PPIP32 "%s: state (%s):\n", p->name, str);
325	{
326		static const char ecr_modes[8][4] = {"SPP", "PS2", "PPF",
327						     "ECP", "EPP", "???",
328						     "TST", "CFG"};
329		unsigned int ecr = readb(priv->regs.ecr);
330		printk(KERN_DEBUG PPIP32 "    ecr=0x%02x", ecr);
331		pr_cont(" %s",
332			ecr_modes[(ecr & ECR_MODE_MASK) >> ECR_MODE_SHIFT]);
333		if (ecr & ECR_nERRINTR)
334			pr_cont(",nErrIntrEn");
335		if (ecr & ECR_DMAEN)
336			pr_cont(",dmaEn");
337		if (ecr & ECR_SERVINTR)
338			pr_cont(",serviceIntr");
339		if (ecr & ECR_F_FULL)
340			pr_cont(",f_full");
341		if (ecr & ECR_F_EMPTY)
342			pr_cont(",f_empty");
343		pr_cont("\n");
344	}
345	if (show_ecp_config) {
346		unsigned int oecr, cnfgA, cnfgB;
347		oecr = readb(priv->regs.ecr);
348		writeb(ECR_MODE_PS2, priv->regs.ecr);
349		writeb(ECR_MODE_CFG, priv->regs.ecr);
350		cnfgA = readb(priv->regs.cnfgA);
351		cnfgB = readb(priv->regs.cnfgB);
352		writeb(ECR_MODE_PS2, priv->regs.ecr);
353		writeb(oecr, priv->regs.ecr);
354		printk(KERN_DEBUG PPIP32 "    cnfgA=0x%02x", cnfgA);
355		pr_cont(" ISA-%s", (cnfgA & CNFGA_IRQ) ? "Level" : "Pulses");
356		switch (cnfgA & CNFGA_ID_MASK) {
357		case CNFGA_ID_8:
358			pr_cont(",8 bits");
359			break;
360		case CNFGA_ID_16:
361			pr_cont(",16 bits");
362			break;
363		case CNFGA_ID_32:
364			pr_cont(",32 bits");
365			break;
366		default:
367			pr_cont(",unknown ID");
368			break;
369		}
370		if (!(cnfgA & CNFGA_nBYTEINTRANS))
371			pr_cont(",ByteInTrans");
372		if ((cnfgA & CNFGA_ID_MASK) != CNFGA_ID_8)
373			pr_cont(",%d byte%s left",
374				cnfgA & CNFGA_PWORDLEFT,
375				((cnfgA & CNFGA_PWORDLEFT) > 1) ? "s" : "");
376		pr_cont("\n");
377		printk(KERN_DEBUG PPIP32 "    cnfgB=0x%02x", cnfgB);
378		pr_cont(" irq=%u,dma=%u",
379			(cnfgB & CNFGB_IRQ_MASK) >> CNFGB_IRQ_SHIFT,
380			(cnfgB & CNFGB_DMA_MASK) >> CNFGB_DMA_SHIFT);
381		pr_cont(",intrValue=%d", !!(cnfgB & CNFGB_INTRVAL));
382		if (cnfgB & CNFGB_COMPRESS)
383			pr_cont(",compress");
384		pr_cont("\n");
385	}
386	for (i = 0; i < 2; i++) {
387		unsigned int dcr = i ? priv->dcr_cache : readb(priv->regs.dcr);
388		printk(KERN_DEBUG PPIP32 "    dcr(%s)=0x%02x",
389		       i ? "soft" : "hard", dcr);
390		pr_cont(" %s", (dcr & DCR_DIR) ? "rev" : "fwd");
391		if (dcr & DCR_IRQ)
392			pr_cont(",ackIntEn");
393		if (!(dcr & DCR_SELECT))
394			pr_cont(",nSelectIn");
395		if (dcr & DCR_nINIT)
396			pr_cont(",nInit");
397		if (!(dcr & DCR_AUTOFD))
398			pr_cont(",nAutoFD");
399		if (!(dcr & DCR_STROBE))
400			pr_cont(",nStrobe");
401		pr_cont("\n");
402	}
403#define sep (f++ ? ',' : ' ')
404	{
405		unsigned int f = 0;
406		unsigned int dsr = readb(priv->regs.dsr);
407		printk(KERN_DEBUG PPIP32 "    dsr=0x%02x", dsr);
408		if (!(dsr & DSR_nBUSY))
409			pr_cont("%cBusy", sep);
410		if (dsr & DSR_nACK)
411			pr_cont("%cnAck", sep);
412		if (dsr & DSR_PERROR)
413			pr_cont("%cPError", sep);
414		if (dsr & DSR_SELECT)
415			pr_cont("%cSelect", sep);
416		if (dsr & DSR_nFAULT)
417			pr_cont("%cnFault", sep);
418		if (!(dsr & DSR_nPRINT))
419			pr_cont("%c(Print)", sep);
420		if (dsr & DSR_TIMEOUT)
421			pr_cont("%cTimeout", sep);
422		pr_cont("\n");
423	}
424#undef sep
425}
426#else /* DEBUG_PARPORT_IP32 < 2 */
427#define parport_ip32_dump_state(...)	do { } while (0)
428#endif
429
430/*
431 * CHECK_EXTRA_BITS - track and log extra bits
432 * @p:		pointer to &struct parport
433 * @b:		byte to inspect
434 * @m:		bit mask of authorized bits
435 *
436 * This is used to track and log extra bits that should not be there in
437 * parport_ip32_write_control() and parport_ip32_frob_control().  It is only
438 * defined if %DEBUG_PARPORT_IP32 >= 1.
439 */
440#if DEBUG_PARPORT_IP32 >= 1
441#define CHECK_EXTRA_BITS(p, b, m)					\
442	do {								\
443		unsigned int __b = (b), __m = (m);			\
444		if (__b & ~__m)						\
445			pr_debug1(PPIP32 "%s: extra bits in %s(%s): "	\
446				  "0x%02x/0x%02x\n",			\
447				  (p)->name, __func__, #b, __b, __m);	\
448	} while (0)
449#else /* DEBUG_PARPORT_IP32 < 1 */
450#define CHECK_EXTRA_BITS(...)	do { } while (0)
451#endif
452
453/*--- IP32 parallel port DMA operations --------------------------------*/
454
455/**
456 * struct parport_ip32_dma_data - private data needed for DMA operation
457 * @dir:	DMA direction (from or to device)
458 * @buf:	buffer physical address
459 * @len:	buffer length
460 * @next:	address of next bytes to DMA transfer
461 * @left:	number of bytes remaining
462 * @ctx:	next context to write (0: context_a; 1: context_b)
463 * @irq_on:	are the DMA IRQs currently enabled?
464 * @lock:	spinlock to protect access to the structure
465 */
466struct parport_ip32_dma_data {
467	enum dma_data_direction		dir;
468	dma_addr_t			buf;
469	dma_addr_t			next;
470	size_t				len;
471	size_t				left;
472	unsigned int			ctx;
473	unsigned int			irq_on;
474	spinlock_t			lock;
475};
476static struct parport_ip32_dma_data parport_ip32_dma;
477
478/**
479 * parport_ip32_dma_setup_context - setup next DMA context
480 * @limit:	maximum data size for the context
481 *
482 * The alignment constraints must be verified in caller function, and the
483 * parameter @limit must be set accordingly.
484 */
485static void parport_ip32_dma_setup_context(unsigned int limit)
486{
487	unsigned long flags;
488
489	spin_lock_irqsave(&parport_ip32_dma.lock, flags);
490	if (parport_ip32_dma.left > 0) {
491		/* Note: ctxreg is "volatile" here only because
492		 * mace->perif.ctrl.parport.context_a and context_b are
493		 * "volatile".  */
494		volatile u64 __iomem *ctxreg = (parport_ip32_dma.ctx == 0) ?
495			&mace->perif.ctrl.parport.context_a :
496			&mace->perif.ctrl.parport.context_b;
497		u64 count;
498		u64 ctxval;
499		if (parport_ip32_dma.left <= limit) {
500			count = parport_ip32_dma.left;
501			ctxval = MACEPAR_CONTEXT_LASTFLAG;
502		} else {
503			count = limit;
504			ctxval = 0;
505		}
506
507		pr_trace(NULL,
508			 "(%u): 0x%04x:0x%04x, %u -> %u%s",
509			 limit,
510			 (unsigned int)parport_ip32_dma.buf,
511			 (unsigned int)parport_ip32_dma.next,
512			 (unsigned int)count,
513			 parport_ip32_dma.ctx, ctxval ? "*" : "");
514
515		ctxval |= parport_ip32_dma.next &
516			MACEPAR_CONTEXT_BASEADDR_MASK;
517		ctxval |= ((count - 1) << MACEPAR_CONTEXT_DATALEN_SHIFT) &
518			MACEPAR_CONTEXT_DATALEN_MASK;
519		writeq(ctxval, ctxreg);
520		parport_ip32_dma.next += count;
521		parport_ip32_dma.left -= count;
522		parport_ip32_dma.ctx ^= 1U;
523	}
524	/* If there is nothing more to send, disable IRQs to avoid to
525	 * face an IRQ storm which can lock the machine.  Disable them
526	 * only once. */
527	if (parport_ip32_dma.left == 0 && parport_ip32_dma.irq_on) {
528		pr_debug(PPIP32 "IRQ off (ctx)\n");
529		disable_irq_nosync(MACEISA_PAR_CTXA_IRQ);
530		disable_irq_nosync(MACEISA_PAR_CTXB_IRQ);
531		parport_ip32_dma.irq_on = 0;
532	}
533	spin_unlock_irqrestore(&parport_ip32_dma.lock, flags);
534}
535
536/**
537 * parport_ip32_dma_interrupt - DMA interrupt handler
538 * @irq:	interrupt number
539 * @dev_id:	unused
540 */
541static irqreturn_t parport_ip32_dma_interrupt(int irq, void *dev_id)
542{
543	if (parport_ip32_dma.left)
544		pr_trace(NULL, "(%d): ctx=%d", irq, parport_ip32_dma.ctx);
545	parport_ip32_dma_setup_context(MACEPAR_CONTEXT_DATA_BOUND);
546	return IRQ_HANDLED;
547}
548
549#if DEBUG_PARPORT_IP32
550static irqreturn_t parport_ip32_merr_interrupt(int irq, void *dev_id)
551{
552	pr_trace1(NULL, "(%d)", irq);
553	return IRQ_HANDLED;
554}
555#endif
556
557/**
558 * parport_ip32_dma_start - begins a DMA transfer
559 * @p:		partport to work on
560 * @dir:	DMA direction: DMA_TO_DEVICE or DMA_FROM_DEVICE
561 * @addr:	pointer to data buffer
562 * @count:	buffer size
563 *
564 * Calls to parport_ip32_dma_start() and parport_ip32_dma_stop() must be
565 * correctly balanced.
566 */
567static int parport_ip32_dma_start(struct parport *p,
568		enum dma_data_direction dir, void *addr, size_t count)
569{
570	unsigned int limit;
571	u64 ctrl;
572
573	pr_trace(NULL, "(%d, %lu)", dir, (unsigned long)count);
574
575	/* FIXME - add support for DMA_FROM_DEVICE.  In this case, buffer must
576	 * be 64 bytes aligned. */
577	BUG_ON(dir != DMA_TO_DEVICE);
578
579	/* Reset DMA controller */
580	ctrl = MACEPAR_CTLSTAT_RESET;
581	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
582
583	/* DMA IRQs should normally be enabled */
584	if (!parport_ip32_dma.irq_on) {
585		WARN_ON(1);
586		enable_irq(MACEISA_PAR_CTXA_IRQ);
587		enable_irq(MACEISA_PAR_CTXB_IRQ);
588		parport_ip32_dma.irq_on = 1;
589	}
590
591	/* Prepare DMA pointers */
592	parport_ip32_dma.dir = dir;
593	parport_ip32_dma.buf = dma_map_single(&p->bus_dev, addr, count, dir);
594	parport_ip32_dma.len = count;
595	parport_ip32_dma.next = parport_ip32_dma.buf;
596	parport_ip32_dma.left = parport_ip32_dma.len;
597	parport_ip32_dma.ctx = 0;
598
599	/* Setup DMA direction and first two contexts */
600	ctrl = (dir == DMA_TO_DEVICE) ? 0 : MACEPAR_CTLSTAT_DIRECTION;
601	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
602	/* Single transfer should not cross a 4K page boundary */
603	limit = MACEPAR_CONTEXT_DATA_BOUND -
604		(parport_ip32_dma.next & (MACEPAR_CONTEXT_DATA_BOUND - 1));
605	parport_ip32_dma_setup_context(limit);
606	parport_ip32_dma_setup_context(MACEPAR_CONTEXT_DATA_BOUND);
607
608	/* Real start of DMA transfer */
609	ctrl |= MACEPAR_CTLSTAT_ENABLE;
610	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
611
612	return 0;
613}
614
615/**
616 * parport_ip32_dma_stop - ends a running DMA transfer
617 * @p:		partport to work on
618 *
619 * Calls to parport_ip32_dma_start() and parport_ip32_dma_stop() must be
620 * correctly balanced.
621 */
622static void parport_ip32_dma_stop(struct parport *p)
623{
624	u64 ctx_a;
625	u64 ctx_b;
626	u64 ctrl;
627	u64 diag;
628	size_t res[2];	/* {[0] = res_a, [1] = res_b} */
629
630	pr_trace(NULL, "()");
631
632	/* Disable IRQs */
633	spin_lock_irq(&parport_ip32_dma.lock);
634	if (parport_ip32_dma.irq_on) {
635		pr_debug(PPIP32 "IRQ off (stop)\n");
636		disable_irq_nosync(MACEISA_PAR_CTXA_IRQ);
637		disable_irq_nosync(MACEISA_PAR_CTXB_IRQ);
638		parport_ip32_dma.irq_on = 0;
639	}
640	spin_unlock_irq(&parport_ip32_dma.lock);
641	/* Force IRQ synchronization, even if the IRQs were disabled
642	 * elsewhere. */
643	synchronize_irq(MACEISA_PAR_CTXA_IRQ);
644	synchronize_irq(MACEISA_PAR_CTXB_IRQ);
645
646	/* Stop DMA transfer */
647	ctrl = readq(&mace->perif.ctrl.parport.cntlstat);
648	ctrl &= ~MACEPAR_CTLSTAT_ENABLE;
649	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
650
651	/* Adjust residue (parport_ip32_dma.left) */
652	ctx_a = readq(&mace->perif.ctrl.parport.context_a);
653	ctx_b = readq(&mace->perif.ctrl.parport.context_b);
654	ctrl = readq(&mace->perif.ctrl.parport.cntlstat);
655	diag = readq(&mace->perif.ctrl.parport.diagnostic);
656	res[0] = (ctrl & MACEPAR_CTLSTAT_CTXA_VALID) ?
657		1 + ((ctx_a & MACEPAR_CONTEXT_DATALEN_MASK) >>
658		     MACEPAR_CONTEXT_DATALEN_SHIFT) :
659		0;
660	res[1] = (ctrl & MACEPAR_CTLSTAT_CTXB_VALID) ?
661		1 + ((ctx_b & MACEPAR_CONTEXT_DATALEN_MASK) >>
662		     MACEPAR_CONTEXT_DATALEN_SHIFT) :
663		0;
664	if (diag & MACEPAR_DIAG_DMACTIVE)
665		res[(diag & MACEPAR_DIAG_CTXINUSE) != 0] =
666			1 + ((diag & MACEPAR_DIAG_CTRMASK) >>
667			     MACEPAR_DIAG_CTRSHIFT);
668	parport_ip32_dma.left += res[0] + res[1];
669
670	/* Reset DMA controller, and re-enable IRQs */
671	ctrl = MACEPAR_CTLSTAT_RESET;
672	writeq(ctrl, &mace->perif.ctrl.parport.cntlstat);
673	pr_debug(PPIP32 "IRQ on (stop)\n");
674	enable_irq(MACEISA_PAR_CTXA_IRQ);
675	enable_irq(MACEISA_PAR_CTXB_IRQ);
676	parport_ip32_dma.irq_on = 1;
677
678	dma_unmap_single(&p->bus_dev, parport_ip32_dma.buf,
679			 parport_ip32_dma.len, parport_ip32_dma.dir);
680}
681
682/**
683 * parport_ip32_dma_get_residue - get residue from last DMA transfer
684 *
685 * Returns the number of bytes remaining from last DMA transfer.
686 */
687static inline size_t parport_ip32_dma_get_residue(void)
688{
689	return parport_ip32_dma.left;
690}
691
692/**
693 * parport_ip32_dma_register - initialize DMA engine
694 *
695 * Returns zero for success.
696 */
697static int parport_ip32_dma_register(void)
698{
699	int err;
700
701	spin_lock_init(&parport_ip32_dma.lock);
702	parport_ip32_dma.irq_on = 1;
703
704	/* Reset DMA controller */
705	writeq(MACEPAR_CTLSTAT_RESET, &mace->perif.ctrl.parport.cntlstat);
706
707	/* Request IRQs */
708	err = request_irq(MACEISA_PAR_CTXA_IRQ, parport_ip32_dma_interrupt,
709			  0, "parport_ip32", NULL);
710	if (err)
711		goto fail_a;
712	err = request_irq(MACEISA_PAR_CTXB_IRQ, parport_ip32_dma_interrupt,
713			  0, "parport_ip32", NULL);
714	if (err)
715		goto fail_b;
716#if DEBUG_PARPORT_IP32
717	/* FIXME - what is this IRQ for? */
718	err = request_irq(MACEISA_PAR_MERR_IRQ, parport_ip32_merr_interrupt,
719			  0, "parport_ip32", NULL);
720	if (err)
721		goto fail_merr;
722#endif
723	return 0;
724
725#if DEBUG_PARPORT_IP32
726fail_merr:
727	free_irq(MACEISA_PAR_CTXB_IRQ, NULL);
728#endif
729fail_b:
730	free_irq(MACEISA_PAR_CTXA_IRQ, NULL);
731fail_a:
732	return err;
733}
734
735/**
736 * parport_ip32_dma_unregister - release and free resources for DMA engine
737 */
738static void parport_ip32_dma_unregister(void)
739{
740#if DEBUG_PARPORT_IP32
741	free_irq(MACEISA_PAR_MERR_IRQ, NULL);
742#endif
743	free_irq(MACEISA_PAR_CTXB_IRQ, NULL);
744	free_irq(MACEISA_PAR_CTXA_IRQ, NULL);
745}
746
747/*--- Interrupt handlers and associates --------------------------------*/
748
749/**
750 * parport_ip32_wakeup - wakes up code waiting for an interrupt
751 * @p:		pointer to &struct parport
752 */
753static inline void parport_ip32_wakeup(struct parport *p)
754{
755	struct parport_ip32_private * const priv = p->physport->private_data;
756	complete(&priv->irq_complete);
757}
758
759/**
760 * parport_ip32_interrupt - interrupt handler
761 * @irq:	interrupt number
762 * @dev_id:	pointer to &struct parport
763 *
764 * Caught interrupts are forwarded to the upper parport layer if IRQ_mode is
765 * %PARPORT_IP32_IRQ_FWD.
766 */
767static irqreturn_t parport_ip32_interrupt(int irq, void *dev_id)
768{
769	struct parport * const p = dev_id;
770	struct parport_ip32_private * const priv = p->physport->private_data;
771	enum parport_ip32_irq_mode irq_mode = priv->irq_mode;
772
773	switch (irq_mode) {
774	case PARPORT_IP32_IRQ_FWD:
775		return parport_irq_handler(irq, dev_id);
776
777	case PARPORT_IP32_IRQ_HERE:
778		parport_ip32_wakeup(p);
779		break;
780	}
781
782	return IRQ_HANDLED;
783}
784
785/*--- Some utility function to manipulate ECR register -----------------*/
786
787/**
788 * parport_ip32_read_econtrol - read contents of the ECR register
789 * @p:		pointer to &struct parport
790 */
791static inline unsigned int parport_ip32_read_econtrol(struct parport *p)
792{
793	struct parport_ip32_private * const priv = p->physport->private_data;
794	return readb(priv->regs.ecr);
795}
796
797/**
798 * parport_ip32_write_econtrol - write new contents to the ECR register
799 * @p:		pointer to &struct parport
800 * @c:		new value to write
801 */
802static inline void parport_ip32_write_econtrol(struct parport *p,
803					       unsigned int c)
804{
805	struct parport_ip32_private * const priv = p->physport->private_data;
806	writeb(c, priv->regs.ecr);
807}
808
809/**
810 * parport_ip32_frob_econtrol - change bits from the ECR register
811 * @p:		pointer to &struct parport
812 * @mask:	bit mask of bits to change
813 * @val:	new value for changed bits
814 *
815 * Read from the ECR, mask out the bits in @mask, exclusive-or with the bits
816 * in @val, and write the result to the ECR.
817 */
818static inline void parport_ip32_frob_econtrol(struct parport *p,
819					      unsigned int mask,
820					      unsigned int val)
821{
822	unsigned int c;
823	c = (parport_ip32_read_econtrol(p) & ~mask) ^ val;
824	parport_ip32_write_econtrol(p, c);
825}
826
827/**
828 * parport_ip32_set_mode - change mode of ECP port
829 * @p:		pointer to &struct parport
830 * @mode:	new mode to write in ECR
831 *
832 * ECR is reset in a sane state (interrupts and DMA disabled), and placed in
833 * mode @mode.  Go through PS2 mode if needed.
834 */
835static void parport_ip32_set_mode(struct parport *p, unsigned int mode)
836{
837	unsigned int omode;
838
839	mode &= ECR_MODE_MASK;
840	omode = parport_ip32_read_econtrol(p) & ECR_MODE_MASK;
841
842	if (!(mode == ECR_MODE_SPP || mode == ECR_MODE_PS2
843	      || omode == ECR_MODE_SPP || omode == ECR_MODE_PS2)) {
844		/* We have to go through PS2 mode */
845		unsigned int ecr = ECR_MODE_PS2 | ECR_nERRINTR | ECR_SERVINTR;
846		parport_ip32_write_econtrol(p, ecr);
847	}
848	parport_ip32_write_econtrol(p, mode | ECR_nERRINTR | ECR_SERVINTR);
849}
850
851/*--- Basic functions needed for parport -------------------------------*/
852
853/**
854 * parport_ip32_read_data - return current contents of the DATA register
855 * @p:		pointer to &struct parport
856 */
857static inline unsigned char parport_ip32_read_data(struct parport *p)
858{
859	struct parport_ip32_private * const priv = p->physport->private_data;
860	return readb(priv->regs.data);
861}
862
863/**
864 * parport_ip32_write_data - set new contents for the DATA register
865 * @p:		pointer to &struct parport
866 * @d:		new value to write
867 */
868static inline void parport_ip32_write_data(struct parport *p, unsigned char d)
869{
870	struct parport_ip32_private * const priv = p->physport->private_data;
871	writeb(d, priv->regs.data);
872}
873
874/**
875 * parport_ip32_read_status - return current contents of the DSR register
876 * @p:		pointer to &struct parport
877 */
878static inline unsigned char parport_ip32_read_status(struct parport *p)
879{
880	struct parport_ip32_private * const priv = p->physport->private_data;
881	return readb(priv->regs.dsr);
882}
883
884/**
885 * __parport_ip32_read_control - return cached contents of the DCR register
886 * @p:		pointer to &struct parport
887 */
888static inline unsigned int __parport_ip32_read_control(struct parport *p)
889{
890	struct parport_ip32_private * const priv = p->physport->private_data;
891	return priv->dcr_cache; /* use soft copy */
892}
893
894/**
895 * __parport_ip32_write_control - set new contents for the DCR register
896 * @p:		pointer to &struct parport
897 * @c:		new value to write
898 */
899static inline void __parport_ip32_write_control(struct parport *p,
900						unsigned int c)
901{
902	struct parport_ip32_private * const priv = p->physport->private_data;
903	CHECK_EXTRA_BITS(p, c, priv->dcr_writable);
904	c &= priv->dcr_writable; /* only writable bits */
905	writeb(c, priv->regs.dcr);
906	priv->dcr_cache = c;		/* update soft copy */
907}
908
909/**
910 * __parport_ip32_frob_control - change bits from the DCR register
911 * @p:		pointer to &struct parport
912 * @mask:	bit mask of bits to change
913 * @val:	new value for changed bits
914 *
915 * This is equivalent to read from the DCR, mask out the bits in @mask,
916 * exclusive-or with the bits in @val, and write the result to the DCR.
917 * Actually, the cached contents of the DCR is used.
918 */
919static inline void __parport_ip32_frob_control(struct parport *p,
920					       unsigned int mask,
921					       unsigned int val)
922{
923	unsigned int c;
924	c = (__parport_ip32_read_control(p) & ~mask) ^ val;
925	__parport_ip32_write_control(p, c);
926}
927
928/**
929 * parport_ip32_read_control - return cached contents of the DCR register
930 * @p:		pointer to &struct parport
931 *
932 * The return value is masked so as to only return the value of %DCR_STROBE,
933 * %DCR_AUTOFD, %DCR_nINIT, and %DCR_SELECT.
934 */
935static inline unsigned char parport_ip32_read_control(struct parport *p)
936{
937	const unsigned int rm =
938		DCR_STROBE | DCR_AUTOFD | DCR_nINIT | DCR_SELECT;
939	return __parport_ip32_read_control(p) & rm;
940}
941
942/**
943 * parport_ip32_write_control - set new contents for the DCR register
944 * @p:		pointer to &struct parport
945 * @c:		new value to write
946 *
947 * The value is masked so as to only change the value of %DCR_STROBE,
948 * %DCR_AUTOFD, %DCR_nINIT, and %DCR_SELECT.
949 */
950static inline void parport_ip32_write_control(struct parport *p,
951					      unsigned char c)
952{
953	const unsigned int wm =
954		DCR_STROBE | DCR_AUTOFD | DCR_nINIT | DCR_SELECT;
955	CHECK_EXTRA_BITS(p, c, wm);
956	__parport_ip32_frob_control(p, wm, c & wm);
957}
958
959/**
960 * parport_ip32_frob_control - change bits from the DCR register
961 * @p:		pointer to &struct parport
962 * @mask:	bit mask of bits to change
963 * @val:	new value for changed bits
964 *
965 * This differs from __parport_ip32_frob_control() in that it only allows to
966 * change the value of %DCR_STROBE, %DCR_AUTOFD, %DCR_nINIT, and %DCR_SELECT.
967 */
968static inline unsigned char parport_ip32_frob_control(struct parport *p,
969						      unsigned char mask,
970						      unsigned char val)
971{
972	const unsigned int wm =
973		DCR_STROBE | DCR_AUTOFD | DCR_nINIT | DCR_SELECT;
974	CHECK_EXTRA_BITS(p, mask, wm);
975	CHECK_EXTRA_BITS(p, val, wm);
976	__parport_ip32_frob_control(p, mask & wm, val & wm);
977	return parport_ip32_read_control(p);
978}
979
980/**
981 * parport_ip32_disable_irq - disable interrupts on the rising edge of nACK
982 * @p:		pointer to &struct parport
983 */
984static inline void parport_ip32_disable_irq(struct parport *p)
985{
986	__parport_ip32_frob_control(p, DCR_IRQ, 0);
987}
988
989/**
990 * parport_ip32_enable_irq - enable interrupts on the rising edge of nACK
991 * @p:		pointer to &struct parport
992 */
993static inline void parport_ip32_enable_irq(struct parport *p)
994{
995	__parport_ip32_frob_control(p, DCR_IRQ, DCR_IRQ);
996}
997
998/**
999 * parport_ip32_data_forward - enable host-to-peripheral communications
1000 * @p:		pointer to &struct parport
1001 *
1002 * Enable the data line drivers, for 8-bit host-to-peripheral communications.
1003 */
1004static inline void parport_ip32_data_forward(struct parport *p)
1005{
1006	__parport_ip32_frob_control(p, DCR_DIR, 0);
1007}
1008
1009/**
1010 * parport_ip32_data_reverse - enable peripheral-to-host communications
1011 * @p:		pointer to &struct parport
1012 *
1013 * Place the data bus in a high impedance state, if @p->modes has the
1014 * PARPORT_MODE_TRISTATE bit set.
1015 */
1016static inline void parport_ip32_data_reverse(struct parport *p)
1017{
1018	__parport_ip32_frob_control(p, DCR_DIR, DCR_DIR);
1019}
1020
1021/**
1022 * parport_ip32_init_state - for core parport code
1023 * @dev:	pointer to &struct pardevice
1024 * @s:		pointer to &struct parport_state to initialize
1025 */
1026static void parport_ip32_init_state(struct pardevice *dev,
1027				    struct parport_state *s)
1028{
1029	s->u.ip32.dcr = DCR_SELECT | DCR_nINIT;
1030	s->u.ip32.ecr = ECR_MODE_PS2 | ECR_nERRINTR | ECR_SERVINTR;
1031}
1032
1033/**
1034 * parport_ip32_save_state - for core parport code
1035 * @p:		pointer to &struct parport
1036 * @s:		pointer to &struct parport_state to save state to
1037 */
1038static void parport_ip32_save_state(struct parport *p,
1039				    struct parport_state *s)
1040{
1041	s->u.ip32.dcr = __parport_ip32_read_control(p);
1042	s->u.ip32.ecr = parport_ip32_read_econtrol(p);
1043}
1044
1045/**
1046 * parport_ip32_restore_state - for core parport code
1047 * @p:		pointer to &struct parport
1048 * @s:		pointer to &struct parport_state to restore state from
1049 */
1050static void parport_ip32_restore_state(struct parport *p,
1051				       struct parport_state *s)
1052{
1053	parport_ip32_set_mode(p, s->u.ip32.ecr & ECR_MODE_MASK);
1054	parport_ip32_write_econtrol(p, s->u.ip32.ecr);
1055	__parport_ip32_write_control(p, s->u.ip32.dcr);
1056}
1057
1058/*--- EPP mode functions -----------------------------------------------*/
1059
1060/**
1061 * parport_ip32_clear_epp_timeout - clear Timeout bit in EPP mode
1062 * @p:		pointer to &struct parport
1063 *
1064 * Returns 1 if the Timeout bit is clear, and 0 otherwise.
1065 */
1066static unsigned int parport_ip32_clear_epp_timeout(struct parport *p)
1067{
1068	struct parport_ip32_private * const priv = p->physport->private_data;
1069	unsigned int cleared;
1070
1071	if (!(parport_ip32_read_status(p) & DSR_TIMEOUT))
1072		cleared = 1;
1073	else {
1074		unsigned int r;
1075		/* To clear timeout some chips require double read */
1076		parport_ip32_read_status(p);
1077		r = parport_ip32_read_status(p);
1078		/* Some reset by writing 1 */
1079		writeb(r | DSR_TIMEOUT, priv->regs.dsr);
1080		/* Others by writing 0 */
1081		writeb(r & ~DSR_TIMEOUT, priv->regs.dsr);
1082
1083		r = parport_ip32_read_status(p);
1084		cleared = !(r & DSR_TIMEOUT);
1085	}
1086
1087	pr_trace(p, "(): %s", cleared ? "cleared" : "failed");
1088	return cleared;
1089}
1090
1091/**
1092 * parport_ip32_epp_read - generic EPP read function
1093 * @eppreg:	I/O register to read from
1094 * @p:		pointer to &struct parport
1095 * @buf:	buffer to store read data
1096 * @len:	length of buffer @buf
1097 * @flags:	may be PARPORT_EPP_FAST
1098 */
1099static size_t parport_ip32_epp_read(void __iomem *eppreg,
1100				    struct parport *p, void *buf,
1101				    size_t len, int flags)
1102{
1103	struct parport_ip32_private * const priv = p->physport->private_data;
1104	size_t got;
1105	parport_ip32_set_mode(p, ECR_MODE_EPP);
1106	parport_ip32_data_reverse(p);
1107	parport_ip32_write_control(p, DCR_nINIT);
1108	if ((flags & PARPORT_EPP_FAST) && (len > 1)) {
1109		readsb(eppreg, buf, len);
1110		if (readb(priv->regs.dsr) & DSR_TIMEOUT) {
1111			parport_ip32_clear_epp_timeout(p);
1112			return -EIO;
1113		}
1114		got = len;
1115	} else {
1116		u8 *bufp = buf;
1117		for (got = 0; got < len; got++) {
1118			*bufp++ = readb(eppreg);
1119			if (readb(priv->regs.dsr) & DSR_TIMEOUT) {
1120				parport_ip32_clear_epp_timeout(p);
1121				break;
1122			}
1123		}
1124	}
1125	parport_ip32_data_forward(p);
1126	parport_ip32_set_mode(p, ECR_MODE_PS2);
1127	return got;
1128}
1129
1130/**
1131 * parport_ip32_epp_write - generic EPP write function
1132 * @eppreg:	I/O register to write to
1133 * @p:		pointer to &struct parport
1134 * @buf:	buffer of data to write
1135 * @len:	length of buffer @buf
1136 * @flags:	may be PARPORT_EPP_FAST
1137 */
1138static size_t parport_ip32_epp_write(void __iomem *eppreg,
1139				     struct parport *p, const void *buf,
1140				     size_t len, int flags)
1141{
1142	struct parport_ip32_private * const priv = p->physport->private_data;
1143	size_t written;
1144	parport_ip32_set_mode(p, ECR_MODE_EPP);
1145	parport_ip32_data_forward(p);
1146	parport_ip32_write_control(p, DCR_nINIT);
1147	if ((flags & PARPORT_EPP_FAST) && (len > 1)) {
1148		writesb(eppreg, buf, len);
1149		if (readb(priv->regs.dsr) & DSR_TIMEOUT) {
1150			parport_ip32_clear_epp_timeout(p);
1151			return -EIO;
1152		}
1153		written = len;
1154	} else {
1155		const u8 *bufp = buf;
1156		for (written = 0; written < len; written++) {
1157			writeb(*bufp++, eppreg);
1158			if (readb(priv->regs.dsr) & DSR_TIMEOUT) {
1159				parport_ip32_clear_epp_timeout(p);
1160				break;
1161			}
1162		}
1163	}
1164	parport_ip32_set_mode(p, ECR_MODE_PS2);
1165	return written;
1166}
1167
1168/**
1169 * parport_ip32_epp_read_data - read a block of data in EPP mode
1170 * @p:		pointer to &struct parport
1171 * @buf:	buffer to store read data
1172 * @len:	length of buffer @buf
1173 * @flags:	may be PARPORT_EPP_FAST
1174 */
1175static size_t parport_ip32_epp_read_data(struct parport *p, void *buf,
1176					 size_t len, int flags)
1177{
1178	struct parport_ip32_private * const priv = p->physport->private_data;
1179	return parport_ip32_epp_read(priv->regs.eppData0, p, buf, len, flags);
1180}
1181
1182/**
1183 * parport_ip32_epp_write_data - write a block of data in EPP mode
1184 * @p:		pointer to &struct parport
1185 * @buf:	buffer of data to write
1186 * @len:	length of buffer @buf
1187 * @flags:	may be PARPORT_EPP_FAST
1188 */
1189static size_t parport_ip32_epp_write_data(struct parport *p, const void *buf,
1190					  size_t len, int flags)
1191{
1192	struct parport_ip32_private * const priv = p->physport->private_data;
1193	return parport_ip32_epp_write(priv->regs.eppData0, p, buf, len, flags);
1194}
1195
1196/**
1197 * parport_ip32_epp_read_addr - read a block of addresses in EPP mode
1198 * @p:		pointer to &struct parport
1199 * @buf:	buffer to store read data
1200 * @len:	length of buffer @buf
1201 * @flags:	may be PARPORT_EPP_FAST
1202 */
1203static size_t parport_ip32_epp_read_addr(struct parport *p, void *buf,
1204					 size_t len, int flags)
1205{
1206	struct parport_ip32_private * const priv = p->physport->private_data;
1207	return parport_ip32_epp_read(priv->regs.eppAddr, p, buf, len, flags);
1208}
1209
1210/**
1211 * parport_ip32_epp_write_addr - write a block of addresses in EPP mode
1212 * @p:		pointer to &struct parport
1213 * @buf:	buffer of data to write
1214 * @len:	length of buffer @buf
1215 * @flags:	may be PARPORT_EPP_FAST
1216 */
1217static size_t parport_ip32_epp_write_addr(struct parport *p, const void *buf,
1218					  size_t len, int flags)
1219{
1220	struct parport_ip32_private * const priv = p->physport->private_data;
1221	return parport_ip32_epp_write(priv->regs.eppAddr, p, buf, len, flags);
1222}
1223
1224/*--- ECP mode functions (FIFO) ----------------------------------------*/
1225
1226/**
1227 * parport_ip32_fifo_wait_break - check if the waiting function should return
1228 * @p:		pointer to &struct parport
1229 * @expire:	timeout expiring date, in jiffies
1230 *
1231 * parport_ip32_fifo_wait_break() checks if the waiting function should return
1232 * immediately or not.  The break conditions are:
1233 *	- expired timeout;
1234 *	- a pending signal;
1235 *	- nFault asserted low.
1236 * This function also calls cond_resched().
1237 */
1238static unsigned int parport_ip32_fifo_wait_break(struct parport *p,
1239						 unsigned long expire)
1240{
1241	cond_resched();
1242	if (time_after(jiffies, expire)) {
1243		pr_debug1(PPIP32 "%s: FIFO write timed out\n", p->name);
1244		return 1;
1245	}
1246	if (signal_pending(current)) {
1247		pr_debug1(PPIP32 "%s: Signal pending\n", p->name);
1248		return 1;
1249	}
1250	if (!(parport_ip32_read_status(p) & DSR_nFAULT)) {
1251		pr_debug1(PPIP32 "%s: nFault asserted low\n", p->name);
1252		return 1;
1253	}
1254	return 0;
1255}
1256
1257/**
1258 * parport_ip32_fwp_wait_polling - wait for FIFO to empty (polling)
1259 * @p:		pointer to &struct parport
1260 *
1261 * Returns the number of bytes that can safely be written in the FIFO.  A
1262 * return value of zero means that the calling function should terminate as
1263 * fast as possible.
1264 */
1265static unsigned int parport_ip32_fwp_wait_polling(struct parport *p)
1266{
1267	struct parport_ip32_private * const priv = p->physport->private_data;
1268	struct parport * const physport = p->physport;
1269	unsigned long expire;
1270	unsigned int count;
1271	unsigned int ecr;
1272
1273	expire = jiffies + physport->cad->timeout;
1274	count = 0;
1275	while (1) {
1276		if (parport_ip32_fifo_wait_break(p, expire))
1277			break;
1278
1279		/* Check FIFO state.  We do nothing when the FIFO is nor full,
1280		 * nor empty.  It appears that the FIFO full bit is not always
1281		 * reliable, the FIFO state is sometimes wrongly reported, and
1282		 * the chip gets confused if we give it another byte. */
1283		ecr = parport_ip32_read_econtrol(p);
1284		if (ecr & ECR_F_EMPTY) {
1285			/* FIFO is empty, fill it up */
1286			count = priv->fifo_depth;
1287			break;
1288		}
1289
1290		/* Wait a moment... */
1291		udelay(FIFO_POLLING_INTERVAL);
1292	} /* while (1) */
1293
1294	return count;
1295}
1296
1297/**
1298 * parport_ip32_fwp_wait_interrupt - wait for FIFO to empty (interrupt-driven)
1299 * @p:		pointer to &struct parport
1300 *
1301 * Returns the number of bytes that can safely be written in the FIFO.  A
1302 * return value of zero means that the calling function should terminate as
1303 * fast as possible.
1304 */
1305static unsigned int parport_ip32_fwp_wait_interrupt(struct parport *p)
1306{
1307	static unsigned int lost_interrupt = 0;
1308	struct parport_ip32_private * const priv = p->physport->private_data;
1309	struct parport * const physport = p->physport;
1310	unsigned long nfault_timeout;
1311	unsigned long expire;
1312	unsigned int count;
1313	unsigned int ecr;
1314
1315	nfault_timeout = min((unsigned long)physport->cad->timeout,
1316			     msecs_to_jiffies(FIFO_NFAULT_TIMEOUT));
1317	expire = jiffies + physport->cad->timeout;
1318	count = 0;
1319	while (1) {
1320		if (parport_ip32_fifo_wait_break(p, expire))
1321			break;
1322
1323		/* Initialize mutex used to take interrupts into account */
1324		reinit_completion(&priv->irq_complete);
1325
1326		/* Enable serviceIntr */
1327		parport_ip32_frob_econtrol(p, ECR_SERVINTR, 0);
1328
1329		/* Enabling serviceIntr while the FIFO is empty does not
1330		 * always generate an interrupt, so check for emptiness
1331		 * now. */
1332		ecr = parport_ip32_read_econtrol(p);
1333		if (!(ecr & ECR_F_EMPTY)) {
1334			/* FIFO is not empty: wait for an interrupt or a
1335			 * timeout to occur */
1336			wait_for_completion_interruptible_timeout(
1337				&priv->irq_complete, nfault_timeout);
1338			ecr = parport_ip32_read_econtrol(p);
1339			if ((ecr & ECR_F_EMPTY) && !(ecr & ECR_SERVINTR)
1340			    && !lost_interrupt) {
1341				pr_warn(PPIP32 "%s: lost interrupt in %s\n",
1342					p->name, __func__);
1343				lost_interrupt = 1;
1344			}
1345		}
1346
1347		/* Disable serviceIntr */
1348		parport_ip32_frob_econtrol(p, ECR_SERVINTR, ECR_SERVINTR);
1349
1350		/* Check FIFO state */
1351		if (ecr & ECR_F_EMPTY) {
1352			/* FIFO is empty, fill it up */
1353			count = priv->fifo_depth;
1354			break;
1355		} else if (ecr & ECR_SERVINTR) {
1356			/* FIFO is not empty, but we know that can safely push
1357			 * writeIntrThreshold bytes into it */
1358			count = priv->writeIntrThreshold;
1359			break;
1360		}
1361		/* FIFO is not empty, and we did not get any interrupt.
1362		 * Either it's time to check for nFault, or a signal is
1363		 * pending.  This is verified in
1364		 * parport_ip32_fifo_wait_break(), so we continue the loop. */
1365	} /* while (1) */
1366
1367	return count;
1368}
1369
1370/**
1371 * parport_ip32_fifo_write_block_pio - write a block of data (PIO mode)
1372 * @p:		pointer to &struct parport
1373 * @buf:	buffer of data to write
1374 * @len:	length of buffer @buf
1375 *
1376 * Uses PIO to write the contents of the buffer @buf into the parallel port
1377 * FIFO.  Returns the number of bytes that were actually written.  It can work
1378 * with or without the help of interrupts.  The parallel port must be
1379 * correctly initialized before calling parport_ip32_fifo_write_block_pio().
1380 */
1381static size_t parport_ip32_fifo_write_block_pio(struct parport *p,
1382						const void *buf, size_t len)
1383{
1384	struct parport_ip32_private * const priv = p->physport->private_data;
1385	const u8 *bufp = buf;
1386	size_t left = len;
1387
1388	priv->irq_mode = PARPORT_IP32_IRQ_HERE;
1389
1390	while (left > 0) {
1391		unsigned int count;
1392
1393		count = (p->irq == PARPORT_IRQ_NONE) ?
1394			parport_ip32_fwp_wait_polling(p) :
1395			parport_ip32_fwp_wait_interrupt(p);
1396		if (count == 0)
1397			break;	/* Transmission should be stopped */
1398		if (count > left)
1399			count = left;
1400		if (count == 1) {
1401			writeb(*bufp, priv->regs.fifo);
1402			bufp++, left--;
1403		} else {
1404			writesb(priv->regs.fifo, bufp, count);
1405			bufp += count, left -= count;
1406		}
1407	}
1408
1409	priv->irq_mode = PARPORT_IP32_IRQ_FWD;
1410
1411	return len - left;
1412}
1413
1414/**
1415 * parport_ip32_fifo_write_block_dma - write a block of data (DMA mode)
1416 * @p:		pointer to &struct parport
1417 * @buf:	buffer of data to write
1418 * @len:	length of buffer @buf
1419 *
1420 * Uses DMA to write the contents of the buffer @buf into the parallel port
1421 * FIFO.  Returns the number of bytes that were actually written.  The
1422 * parallel port must be correctly initialized before calling
1423 * parport_ip32_fifo_write_block_dma().
1424 */
1425static size_t parport_ip32_fifo_write_block_dma(struct parport *p,
1426						const void *buf, size_t len)
1427{
1428	struct parport_ip32_private * const priv = p->physport->private_data;
1429	struct parport * const physport = p->physport;
1430	unsigned long nfault_timeout;
1431	unsigned long expire;
1432	size_t written;
1433	unsigned int ecr;
1434
1435	priv->irq_mode = PARPORT_IP32_IRQ_HERE;
1436
1437	parport_ip32_dma_start(p, DMA_TO_DEVICE, (void *)buf, len);
1438	reinit_completion(&priv->irq_complete);
1439	parport_ip32_frob_econtrol(p, ECR_DMAEN | ECR_SERVINTR, ECR_DMAEN);
1440
1441	nfault_timeout = min((unsigned long)physport->cad->timeout,
1442			     msecs_to_jiffies(FIFO_NFAULT_TIMEOUT));
1443	expire = jiffies + physport->cad->timeout;
1444	while (1) {
1445		if (parport_ip32_fifo_wait_break(p, expire))
1446			break;
1447		wait_for_completion_interruptible_timeout(&priv->irq_complete,
1448							  nfault_timeout);
1449		ecr = parport_ip32_read_econtrol(p);
1450		if (ecr & ECR_SERVINTR)
1451			break;	/* DMA transfer just finished */
1452	}
1453	parport_ip32_dma_stop(p);
1454	written = len - parport_ip32_dma_get_residue();
1455
1456	priv->irq_mode = PARPORT_IP32_IRQ_FWD;
1457
1458	return written;
1459}
1460
1461/**
1462 * parport_ip32_fifo_write_block - write a block of data
1463 * @p:		pointer to &struct parport
1464 * @buf:	buffer of data to write
1465 * @len:	length of buffer @buf
1466 *
1467 * Uses PIO or DMA to write the contents of the buffer @buf into the parallel
1468 * p FIFO.  Returns the number of bytes that were actually written.
1469 */
1470static size_t parport_ip32_fifo_write_block(struct parport *p,
1471					    const void *buf, size_t len)
1472{
1473	size_t written = 0;
1474	if (len)
1475		/* FIXME - Maybe some threshold value should be set for @len
1476		 * under which we revert to PIO mode? */
1477		written = (p->modes & PARPORT_MODE_DMA) ?
1478			parport_ip32_fifo_write_block_dma(p, buf, len) :
1479			parport_ip32_fifo_write_block_pio(p, buf, len);
1480	return written;
1481}
1482
1483/**
1484 * parport_ip32_drain_fifo - wait for FIFO to empty
1485 * @p:		pointer to &struct parport
1486 * @timeout:	timeout, in jiffies
1487 *
1488 * This function waits for FIFO to empty.  It returns 1 when FIFO is empty, or
1489 * 0 if the timeout @timeout is reached before, or if a signal is pending.
1490 */
1491static unsigned int parport_ip32_drain_fifo(struct parport *p,
1492					    unsigned long timeout)
1493{
1494	unsigned long expire = jiffies + timeout;
1495	unsigned int polling_interval;
1496	unsigned int counter;
1497
1498	/* Busy wait for approx. 200us */
1499	for (counter = 0; counter < 40; counter++) {
1500		if (parport_ip32_read_econtrol(p) & ECR_F_EMPTY)
1501			break;
1502		if (time_after(jiffies, expire))
1503			break;
1504		if (signal_pending(current))
1505			break;
1506		udelay(5);
1507	}
1508	/* Poll slowly.  Polling interval starts with 1 millisecond, and is
1509	 * increased exponentially until 128.  */
1510	polling_interval = 1; /* msecs */
1511	while (!(parport_ip32_read_econtrol(p) & ECR_F_EMPTY)) {
1512		if (time_after_eq(jiffies, expire))
1513			break;
1514		msleep_interruptible(polling_interval);
1515		if (signal_pending(current))
1516			break;
1517		if (polling_interval < 128)
1518			polling_interval *= 2;
1519	}
1520
1521	return !!(parport_ip32_read_econtrol(p) & ECR_F_EMPTY);
1522}
1523
1524/**
1525 * parport_ip32_get_fifo_residue - reset FIFO
1526 * @p:		pointer to &struct parport
1527 * @mode:	current operation mode (ECR_MODE_PPF or ECR_MODE_ECP)
1528 *
1529 * This function resets FIFO, and returns the number of bytes remaining in it.
1530 */
1531static unsigned int parport_ip32_get_fifo_residue(struct parport *p,
1532						  unsigned int mode)
1533{
1534	struct parport_ip32_private * const priv = p->physport->private_data;
1535	unsigned int residue;
1536	unsigned int cnfga;
1537
1538	/* FIXME - We are missing one byte if the printer is off-line.  I
1539	 * don't know how to detect this.  It looks that the full bit is not
1540	 * always reliable.  For the moment, the problem is avoided in most
1541	 * cases by testing for BUSY in parport_ip32_compat_write_data().
1542	 */
1543	if (parport_ip32_read_econtrol(p) & ECR_F_EMPTY)
1544		residue = 0;
1545	else {
1546		pr_debug1(PPIP32 "%s: FIFO is stuck\n", p->name);
1547
1548		/* Stop all transfers.
1549		 *
1550		 * Microsoft's document instructs to drive DCR_STROBE to 0,
1551		 * but it doesn't work (at least in Compatibility mode, not
1552		 * tested in ECP mode).  Switching directly to Test mode (as
1553		 * in parport_pc) is not an option: it does confuse the port,
1554		 * ECP service interrupts are no more working after that.  A
1555		 * hard reset is then needed to revert to a sane state.
1556		 *
1557		 * Let's hope that the FIFO is really stuck and that the
1558		 * peripheral doesn't wake up now.
1559		 */
1560		parport_ip32_frob_control(p, DCR_STROBE, 0);
1561
1562		/* Fill up FIFO */
1563		for (residue = priv->fifo_depth; residue > 0; residue--) {
1564			if (parport_ip32_read_econtrol(p) & ECR_F_FULL)
1565				break;
1566			writeb(0x00, priv->regs.fifo);
1567		}
1568	}
1569	if (residue)
1570		pr_debug1(PPIP32 "%s: %d PWord%s left in FIFO\n",
1571			  p->name, residue,
1572			  (residue == 1) ? " was" : "s were");
1573
1574	/* Now reset the FIFO */
1575	parport_ip32_set_mode(p, ECR_MODE_PS2);
1576
1577	/* Host recovery for ECP mode */
1578	if (mode == ECR_MODE_ECP) {
1579		parport_ip32_data_reverse(p);
1580		parport_ip32_frob_control(p, DCR_nINIT, 0);
1581		if (parport_wait_peripheral(p, DSR_PERROR, 0))
1582			pr_debug1(PPIP32 "%s: PEerror timeout 1 in %s\n",
1583				  p->name, __func__);
1584		parport_ip32_frob_control(p, DCR_STROBE, DCR_STROBE);
1585		parport_ip32_frob_control(p, DCR_nINIT, DCR_nINIT);
1586		if (parport_wait_peripheral(p, DSR_PERROR, DSR_PERROR))
1587			pr_debug1(PPIP32 "%s: PEerror timeout 2 in %s\n",
1588				  p->name, __func__);
1589	}
1590
1591	/* Adjust residue if needed */
1592	parport_ip32_set_mode(p, ECR_MODE_CFG);
1593	cnfga = readb(priv->regs.cnfgA);
1594	if (!(cnfga & CNFGA_nBYTEINTRANS)) {
1595		pr_debug1(PPIP32 "%s: cnfgA contains 0x%02x\n",
1596			  p->name, cnfga);
1597		pr_debug1(PPIP32 "%s: Accounting for extra byte\n",
1598			  p->name);
1599		residue++;
1600	}
1601
1602	/* Don't care about partial PWords since we do not support
1603	 * PWord != 1 byte. */
1604
1605	/* Back to forward PS2 mode. */
1606	parport_ip32_set_mode(p, ECR_MODE_PS2);
1607	parport_ip32_data_forward(p);
1608
1609	return residue;
1610}
1611
1612/**
1613 * parport_ip32_compat_write_data - write a block of data in SPP mode
1614 * @p:		pointer to &struct parport
1615 * @buf:	buffer of data to write
1616 * @len:	length of buffer @buf
1617 * @flags:	ignored
1618 */
1619static size_t parport_ip32_compat_write_data(struct parport *p,
1620					     const void *buf, size_t len,
1621					     int flags)
1622{
1623	static unsigned int ready_before = 1;
1624	struct parport_ip32_private * const priv = p->physport->private_data;
1625	struct parport * const physport = p->physport;
1626	size_t written = 0;
1627
1628	/* Special case: a timeout of zero means we cannot call schedule().
1629	 * Also if O_NONBLOCK is set then use the default implementation. */
1630	if (physport->cad->timeout <= PARPORT_INACTIVITY_O_NONBLOCK)
1631		return parport_ieee1284_write_compat(p, buf, len, flags);
1632
1633	/* Reset FIFO, go in forward mode, and disable ackIntEn */
1634	parport_ip32_set_mode(p, ECR_MODE_PS2);
1635	parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);
1636	parport_ip32_data_forward(p);
1637	parport_ip32_disable_irq(p);
1638	parport_ip32_set_mode(p, ECR_MODE_PPF);
1639	physport->ieee1284.phase = IEEE1284_PH_FWD_DATA;
1640
1641	/* Wait for peripheral to become ready */
1642	if (parport_wait_peripheral(p, DSR_nBUSY | DSR_nFAULT,
1643				       DSR_nBUSY | DSR_nFAULT)) {
1644		/* Avoid to flood the logs */
1645		if (ready_before)
1646			pr_info(PPIP32 "%s: not ready in %s\n",
1647				p->name, __func__);
1648		ready_before = 0;
1649		goto stop;
1650	}
1651	ready_before = 1;
1652
1653	written = parport_ip32_fifo_write_block(p, buf, len);
1654
1655	/* Wait FIFO to empty.  Timeout is proportional to FIFO_depth.  */
1656	parport_ip32_drain_fifo(p, physport->cad->timeout * priv->fifo_depth);
1657
1658	/* Check for a potential residue */
1659	written -= parport_ip32_get_fifo_residue(p, ECR_MODE_PPF);
1660
1661	/* Then, wait for BUSY to get low. */
1662	if (parport_wait_peripheral(p, DSR_nBUSY, DSR_nBUSY))
1663		printk(KERN_DEBUG PPIP32 "%s: BUSY timeout in %s\n",
1664		       p->name, __func__);
1665
1666stop:
1667	/* Reset FIFO */
1668	parport_ip32_set_mode(p, ECR_MODE_PS2);
1669	physport->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
1670
1671	return written;
1672}
1673
1674/*
1675 * FIXME - Insert here parport_ip32_ecp_read_data().
1676 */
1677
1678/**
1679 * parport_ip32_ecp_write_data - write a block of data in ECP mode
1680 * @p:		pointer to &struct parport
1681 * @buf:	buffer of data to write
1682 * @len:	length of buffer @buf
1683 * @flags:	ignored
1684 */
1685static size_t parport_ip32_ecp_write_data(struct parport *p,
1686					  const void *buf, size_t len,
1687					  int flags)
1688{
1689	static unsigned int ready_before = 1;
1690	struct parport_ip32_private * const priv = p->physport->private_data;
1691	struct parport * const physport = p->physport;
1692	size_t written = 0;
1693
1694	/* Special case: a timeout of zero means we cannot call schedule().
1695	 * Also if O_NONBLOCK is set then use the default implementation. */
1696	if (physport->cad->timeout <= PARPORT_INACTIVITY_O_NONBLOCK)
1697		return parport_ieee1284_ecp_write_data(p, buf, len, flags);
1698
1699	/* Negotiate to forward mode if necessary. */
1700	if (physport->ieee1284.phase != IEEE1284_PH_FWD_IDLE) {
1701		/* Event 47: Set nInit high. */
1702		parport_ip32_frob_control(p, DCR_nINIT | DCR_AUTOFD,
1703					     DCR_nINIT | DCR_AUTOFD);
1704
1705		/* Event 49: PError goes high. */
1706		if (parport_wait_peripheral(p, DSR_PERROR, DSR_PERROR)) {
1707			printk(KERN_DEBUG PPIP32 "%s: PError timeout in %s\n",
1708			       p->name, __func__);
1709			physport->ieee1284.phase = IEEE1284_PH_ECP_DIR_UNKNOWN;
1710			return 0;
1711		}
1712	}
1713
1714	/* Reset FIFO, go in forward mode, and disable ackIntEn */
1715	parport_ip32_set_mode(p, ECR_MODE_PS2);
1716	parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);
1717	parport_ip32_data_forward(p);
1718	parport_ip32_disable_irq(p);
1719	parport_ip32_set_mode(p, ECR_MODE_ECP);
1720	physport->ieee1284.phase = IEEE1284_PH_FWD_DATA;
1721
1722	/* Wait for peripheral to become ready */
1723	if (parport_wait_peripheral(p, DSR_nBUSY | DSR_nFAULT,
1724				       DSR_nBUSY | DSR_nFAULT)) {
1725		/* Avoid to flood the logs */
1726		if (ready_before)
1727			pr_info(PPIP32 "%s: not ready in %s\n",
1728				p->name, __func__);
1729		ready_before = 0;
1730		goto stop;
1731	}
1732	ready_before = 1;
1733
1734	written = parport_ip32_fifo_write_block(p, buf, len);
1735
1736	/* Wait FIFO to empty.  Timeout is proportional to FIFO_depth.  */
1737	parport_ip32_drain_fifo(p, physport->cad->timeout * priv->fifo_depth);
1738
1739	/* Check for a potential residue */
1740	written -= parport_ip32_get_fifo_residue(p, ECR_MODE_ECP);
1741
1742	/* Then, wait for BUSY to get low. */
1743	if (parport_wait_peripheral(p, DSR_nBUSY, DSR_nBUSY))
1744		printk(KERN_DEBUG PPIP32 "%s: BUSY timeout in %s\n",
1745		       p->name, __func__);
1746
1747stop:
1748	/* Reset FIFO */
1749	parport_ip32_set_mode(p, ECR_MODE_PS2);
1750	physport->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
1751
1752	return written;
1753}
1754
1755/*
1756 * FIXME - Insert here parport_ip32_ecp_write_addr().
1757 */
1758
1759/*--- Default parport operations ---------------------------------------*/
1760
1761static const struct parport_operations parport_ip32_ops __initconst = {
1762	.write_data		= parport_ip32_write_data,
1763	.read_data		= parport_ip32_read_data,
1764
1765	.write_control		= parport_ip32_write_control,
1766	.read_control		= parport_ip32_read_control,
1767	.frob_control		= parport_ip32_frob_control,
1768
1769	.read_status		= parport_ip32_read_status,
1770
1771	.enable_irq		= parport_ip32_enable_irq,
1772	.disable_irq		= parport_ip32_disable_irq,
1773
1774	.data_forward		= parport_ip32_data_forward,
1775	.data_reverse		= parport_ip32_data_reverse,
1776
1777	.init_state		= parport_ip32_init_state,
1778	.save_state		= parport_ip32_save_state,
1779	.restore_state		= parport_ip32_restore_state,
1780
1781	.epp_write_data		= parport_ieee1284_epp_write_data,
1782	.epp_read_data		= parport_ieee1284_epp_read_data,
1783	.epp_write_addr		= parport_ieee1284_epp_write_addr,
1784	.epp_read_addr		= parport_ieee1284_epp_read_addr,
1785
1786	.ecp_write_data		= parport_ieee1284_ecp_write_data,
1787	.ecp_read_data		= parport_ieee1284_ecp_read_data,
1788	.ecp_write_addr		= parport_ieee1284_ecp_write_addr,
1789
1790	.compat_write_data	= parport_ieee1284_write_compat,
1791	.nibble_read_data	= parport_ieee1284_read_nibble,
1792	.byte_read_data		= parport_ieee1284_read_byte,
1793
1794	.owner			= THIS_MODULE,
1795};
1796
1797/*--- Device detection -------------------------------------------------*/
1798
1799/**
1800 * parport_ip32_ecp_supported - check for an ECP port
1801 * @p:		pointer to the &parport structure
1802 *
1803 * Returns 1 if an ECP port is found, and 0 otherwise.  This function actually
1804 * checks if an Extended Control Register seems to be present.  On successful
1805 * return, the port is placed in SPP mode.
1806 */
1807static __init unsigned int parport_ip32_ecp_supported(struct parport *p)
1808{
1809	struct parport_ip32_private * const priv = p->physport->private_data;
1810	unsigned int ecr;
1811
1812	ecr = ECR_MODE_PS2 | ECR_nERRINTR | ECR_SERVINTR;
1813	writeb(ecr, priv->regs.ecr);
1814	if (readb(priv->regs.ecr) != (ecr | ECR_F_EMPTY))
1815		goto fail;
1816
1817	pr_probe(p, "Found working ECR register\n");
1818	parport_ip32_set_mode(p, ECR_MODE_SPP);
1819	parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);
1820	return 1;
1821
1822fail:
1823	pr_probe(p, "ECR register not found\n");
1824	return 0;
1825}
1826
1827/**
1828 * parport_ip32_fifo_supported - check for FIFO parameters
1829 * @p:		pointer to the &parport structure
1830 *
1831 * Check for FIFO parameters of an Extended Capabilities Port.  Returns 1 on
1832 * success, and 0 otherwise.  Adjust FIFO parameters in the parport structure.
1833 * On return, the port is placed in SPP mode.
1834 */
1835static __init unsigned int parport_ip32_fifo_supported(struct parport *p)
1836{
1837	struct parport_ip32_private * const priv = p->physport->private_data;
1838	unsigned int configa, configb;
1839	unsigned int pword;
1840	unsigned int i;
1841
1842	/* Configuration mode */
1843	parport_ip32_set_mode(p, ECR_MODE_CFG);
1844	configa = readb(priv->regs.cnfgA);
1845	configb = readb(priv->regs.cnfgB);
1846
1847	/* Find out PWord size */
1848	switch (configa & CNFGA_ID_MASK) {
1849	case CNFGA_ID_8:
1850		pword = 1;
1851		break;
1852	case CNFGA_ID_16:
1853		pword = 2;
1854		break;
1855	case CNFGA_ID_32:
1856		pword = 4;
1857		break;
1858	default:
1859		pr_probe(p, "Unknown implementation ID: 0x%0x\n",
1860			 (configa & CNFGA_ID_MASK) >> CNFGA_ID_SHIFT);
1861		goto fail;
1862		break;
1863	}
1864	if (pword != 1) {
1865		pr_probe(p, "Unsupported PWord size: %u\n", pword);
1866		goto fail;
1867	}
1868	priv->pword = pword;
1869	pr_probe(p, "PWord is %u bits\n", 8 * priv->pword);
1870
1871	/* Check for compression support */
1872	writeb(configb | CNFGB_COMPRESS, priv->regs.cnfgB);
1873	if (readb(priv->regs.cnfgB) & CNFGB_COMPRESS)
1874		pr_probe(p, "Hardware compression detected (unsupported)\n");
1875	writeb(configb & ~CNFGB_COMPRESS, priv->regs.cnfgB);
1876
1877	/* Reset FIFO and go in test mode (no interrupt, no DMA) */
1878	parport_ip32_set_mode(p, ECR_MODE_TST);
1879
1880	/* FIFO must be empty now */
1881	if (!(readb(priv->regs.ecr) & ECR_F_EMPTY)) {
1882		pr_probe(p, "FIFO not reset\n");
1883		goto fail;
1884	}
1885
1886	/* Find out FIFO depth. */
1887	priv->fifo_depth = 0;
1888	for (i = 0; i < 1024; i++) {
1889		if (readb(priv->regs.ecr) & ECR_F_FULL) {
1890			/* FIFO full */
1891			priv->fifo_depth = i;
1892			break;
1893		}
1894		writeb((u8)i, priv->regs.fifo);
1895	}
1896	if (i >= 1024) {
1897		pr_probe(p, "Can't fill FIFO\n");
1898		goto fail;
1899	}
1900	if (!priv->fifo_depth) {
1901		pr_probe(p, "Can't get FIFO depth\n");
1902		goto fail;
1903	}
1904	pr_probe(p, "FIFO is %u PWords deep\n", priv->fifo_depth);
1905
1906	/* Enable interrupts */
1907	parport_ip32_frob_econtrol(p, ECR_SERVINTR, 0);
1908
1909	/* Find out writeIntrThreshold: number of PWords we know we can write
1910	 * if we get an interrupt. */
1911	priv->writeIntrThreshold = 0;
1912	for (i = 0; i < priv->fifo_depth; i++) {
1913		if (readb(priv->regs.fifo) != (u8)i) {
1914			pr_probe(p, "Invalid data in FIFO\n");
1915			goto fail;
1916		}
1917		if (!priv->writeIntrThreshold
1918		    && readb(priv->regs.ecr) & ECR_SERVINTR)
1919			/* writeIntrThreshold reached */
1920			priv->writeIntrThreshold = i + 1;
1921		if (i + 1 < priv->fifo_depth
1922		    && readb(priv->regs.ecr) & ECR_F_EMPTY) {
1923			/* FIFO empty before the last byte? */
1924			pr_probe(p, "Data lost in FIFO\n");
1925			goto fail;
1926		}
1927	}
1928	if (!priv->writeIntrThreshold) {
1929		pr_probe(p, "Can't get writeIntrThreshold\n");
1930		goto fail;
1931	}
1932	pr_probe(p, "writeIntrThreshold is %u\n", priv->writeIntrThreshold);
1933
1934	/* FIFO must be empty now */
1935	if (!(readb(priv->regs.ecr) & ECR_F_EMPTY)) {
1936		pr_probe(p, "Can't empty FIFO\n");
1937		goto fail;
1938	}
1939
1940	/* Reset FIFO */
1941	parport_ip32_set_mode(p, ECR_MODE_PS2);
1942	/* Set reverse direction (must be in PS2 mode) */
1943	parport_ip32_data_reverse(p);
1944	/* Test FIFO, no interrupt, no DMA */
1945	parport_ip32_set_mode(p, ECR_MODE_TST);
1946	/* Enable interrupts */
1947	parport_ip32_frob_econtrol(p, ECR_SERVINTR, 0);
1948
1949	/* Find out readIntrThreshold: number of PWords we can read if we get
1950	 * an interrupt. */
1951	priv->readIntrThreshold = 0;
1952	for (i = 0; i < priv->fifo_depth; i++) {
1953		writeb(0xaa, priv->regs.fifo);
1954		if (readb(priv->regs.ecr) & ECR_SERVINTR) {
1955			/* readIntrThreshold reached */
1956			priv->readIntrThreshold = i + 1;
1957			break;
1958		}
1959	}
1960	if (!priv->readIntrThreshold) {
1961		pr_probe(p, "Can't get readIntrThreshold\n");
1962		goto fail;
1963	}
1964	pr_probe(p, "readIntrThreshold is %u\n", priv->readIntrThreshold);
1965
1966	/* Reset ECR */
1967	parport_ip32_set_mode(p, ECR_MODE_PS2);
1968	parport_ip32_data_forward(p);
1969	parport_ip32_set_mode(p, ECR_MODE_SPP);
1970	return 1;
1971
1972fail:
1973	priv->fifo_depth = 0;
1974	parport_ip32_set_mode(p, ECR_MODE_SPP);
1975	return 0;
1976}
1977
1978/*--- Initialization code ----------------------------------------------*/
1979
1980/**
1981 * parport_ip32_make_isa_registers - compute (ISA) register addresses
1982 * @regs:	pointer to &struct parport_ip32_regs to fill
1983 * @base:	base address of standard and EPP registers
1984 * @base_hi:	base address of ECP registers
1985 * @regshift:	how much to shift register offset by
1986 *
1987 * Compute register addresses, according to the ISA standard.  The addresses
1988 * of the standard and EPP registers are computed from address @base.  The
1989 * addresses of the ECP registers are computed from address @base_hi.
1990 */
1991static void __init
1992parport_ip32_make_isa_registers(struct parport_ip32_regs *regs,
1993				void __iomem *base, void __iomem *base_hi,
1994				unsigned int regshift)
1995{
1996#define r_base(offset)    ((u8 __iomem *)base    + ((offset) << regshift))
1997#define r_base_hi(offset) ((u8 __iomem *)base_hi + ((offset) << regshift))
1998	*regs = (struct parport_ip32_regs){
1999		.data		= r_base(0),
2000		.dsr		= r_base(1),
2001		.dcr		= r_base(2),
2002		.eppAddr	= r_base(3),
2003		.eppData0	= r_base(4),
2004		.eppData1	= r_base(5),
2005		.eppData2	= r_base(6),
2006		.eppData3	= r_base(7),
2007		.ecpAFifo	= r_base(0),
2008		.fifo		= r_base_hi(0),
2009		.cnfgA		= r_base_hi(0),
2010		.cnfgB		= r_base_hi(1),
2011		.ecr		= r_base_hi(2)
2012	};
2013#undef r_base_hi
2014#undef r_base
2015}
2016
2017/**
2018 * parport_ip32_probe_port - probe and register IP32 built-in parallel port
2019 *
2020 * Returns the new allocated &parport structure.  On error, an error code is
2021 * encoded in return value with the ERR_PTR function.
2022 */
2023static __init struct parport *parport_ip32_probe_port(void)
2024{
2025	struct parport_ip32_regs regs;
2026	struct parport_ip32_private *priv = NULL;
2027	struct parport_operations *ops = NULL;
2028	struct parport *p = NULL;
2029	int err;
2030
2031	parport_ip32_make_isa_registers(&regs, &mace->isa.parallel,
2032					&mace->isa.ecp1284, 8 /* regshift */);
2033
2034	ops = kmalloc(sizeof(struct parport_operations), GFP_KERNEL);
2035	priv = kmalloc(sizeof(struct parport_ip32_private), GFP_KERNEL);
2036	p = parport_register_port(0, PARPORT_IRQ_NONE, PARPORT_DMA_NONE, ops);
2037	if (ops == NULL || priv == NULL || p == NULL) {
2038		err = -ENOMEM;
2039		goto fail;
2040	}
2041	p->base = MACE_BASE + offsetof(struct sgi_mace, isa.parallel);
2042	p->base_hi = MACE_BASE + offsetof(struct sgi_mace, isa.ecp1284);
2043	p->private_data = priv;
2044
2045	*ops = parport_ip32_ops;
2046	*priv = (struct parport_ip32_private){
2047		.regs			= regs,
2048		.dcr_writable		= DCR_DIR | DCR_SELECT | DCR_nINIT |
2049					  DCR_AUTOFD | DCR_STROBE,
2050		.irq_mode		= PARPORT_IP32_IRQ_FWD,
2051	};
2052	init_completion(&priv->irq_complete);
2053
2054	/* Probe port. */
2055	if (!parport_ip32_ecp_supported(p)) {
2056		err = -ENODEV;
2057		goto fail;
2058	}
2059	parport_ip32_dump_state(p, "begin init", 0);
2060
2061	/* We found what looks like a working ECR register.  Simply assume
2062	 * that all modes are correctly supported.  Enable basic modes. */
2063	p->modes = PARPORT_MODE_PCSPP | PARPORT_MODE_SAFEININT;
2064	p->modes |= PARPORT_MODE_TRISTATE;
2065
2066	if (!parport_ip32_fifo_supported(p)) {
2067		pr_warn(PPIP32 "%s: error: FIFO disabled\n", p->name);
2068		/* Disable hardware modes depending on a working FIFO. */
2069		features &= ~PARPORT_IP32_ENABLE_SPP;
2070		features &= ~PARPORT_IP32_ENABLE_ECP;
2071		/* DMA is not needed if FIFO is not supported.  */
2072		features &= ~PARPORT_IP32_ENABLE_DMA;
2073	}
2074
2075	/* Request IRQ */
2076	if (features & PARPORT_IP32_ENABLE_IRQ) {
2077		int irq = MACEISA_PARALLEL_IRQ;
2078		if (request_irq(irq, parport_ip32_interrupt, 0, p->name, p)) {
2079			pr_warn(PPIP32 "%s: error: IRQ disabled\n", p->name);
2080			/* DMA cannot work without interrupts. */
2081			features &= ~PARPORT_IP32_ENABLE_DMA;
2082		} else {
2083			pr_probe(p, "Interrupt support enabled\n");
2084			p->irq = irq;
2085			priv->dcr_writable |= DCR_IRQ;
2086		}
2087	}
2088
2089	/* Allocate DMA resources */
2090	if (features & PARPORT_IP32_ENABLE_DMA) {
2091		if (parport_ip32_dma_register())
2092			pr_warn(PPIP32 "%s: error: DMA disabled\n", p->name);
2093		else {
2094			pr_probe(p, "DMA support enabled\n");
2095			p->dma = 0; /* arbitrary value != PARPORT_DMA_NONE */
2096			p->modes |= PARPORT_MODE_DMA;
2097		}
2098	}
2099
2100	if (features & PARPORT_IP32_ENABLE_SPP) {
2101		/* Enable compatibility FIFO mode */
2102		p->ops->compat_write_data = parport_ip32_compat_write_data;
2103		p->modes |= PARPORT_MODE_COMPAT;
2104		pr_probe(p, "Hardware support for SPP mode enabled\n");
2105	}
2106	if (features & PARPORT_IP32_ENABLE_EPP) {
2107		/* Set up access functions to use EPP hardware. */
2108		p->ops->epp_read_data = parport_ip32_epp_read_data;
2109		p->ops->epp_write_data = parport_ip32_epp_write_data;
2110		p->ops->epp_read_addr = parport_ip32_epp_read_addr;
2111		p->ops->epp_write_addr = parport_ip32_epp_write_addr;
2112		p->modes |= PARPORT_MODE_EPP;
2113		pr_probe(p, "Hardware support for EPP mode enabled\n");
2114	}
2115	if (features & PARPORT_IP32_ENABLE_ECP) {
2116		/* Enable ECP FIFO mode */
2117		p->ops->ecp_write_data = parport_ip32_ecp_write_data;
2118		/* FIXME - not implemented */
2119/*		p->ops->ecp_read_data  = parport_ip32_ecp_read_data; */
2120/*		p->ops->ecp_write_addr = parport_ip32_ecp_write_addr; */
2121		p->modes |= PARPORT_MODE_ECP;
2122		pr_probe(p, "Hardware support for ECP mode enabled\n");
2123	}
2124
2125	/* Initialize the port with sensible values */
2126	parport_ip32_set_mode(p, ECR_MODE_PS2);
2127	parport_ip32_write_control(p, DCR_SELECT | DCR_nINIT);
2128	parport_ip32_data_forward(p);
2129	parport_ip32_disable_irq(p);
2130	parport_ip32_write_data(p, 0x00);
2131	parport_ip32_dump_state(p, "end init", 0);
2132
2133	/* Print out what we found */
2134	pr_info("%s: SGI IP32 at 0x%lx (0x%lx)", p->name, p->base, p->base_hi);
2135	if (p->irq != PARPORT_IRQ_NONE)
2136		pr_cont(", irq %d", p->irq);
2137	pr_cont(" [");
2138#define printmode(x)							\
2139do {									\
2140	if (p->modes & PARPORT_MODE_##x)				\
2141		pr_cont("%s%s", f++ ? "," : "", #x);			\
2142} while (0)
2143	{
2144		unsigned int f = 0;
2145		printmode(PCSPP);
2146		printmode(TRISTATE);
2147		printmode(COMPAT);
2148		printmode(EPP);
2149		printmode(ECP);
2150		printmode(DMA);
2151	}
2152#undef printmode
2153	pr_cont("]\n");
2154
2155	parport_announce_port(p);
2156	return p;
2157
2158fail:
2159	if (p)
2160		parport_put_port(p);
2161	kfree(priv);
2162	kfree(ops);
2163	return ERR_PTR(err);
2164}
2165
2166/**
2167 * parport_ip32_unregister_port - unregister a parallel port
2168 * @p:		pointer to the &struct parport
2169 *
2170 * Unregisters a parallel port and free previously allocated resources
2171 * (memory, IRQ, ...).
2172 */
2173static __exit void parport_ip32_unregister_port(struct parport *p)
2174{
2175	struct parport_ip32_private * const priv = p->physport->private_data;
2176	struct parport_operations *ops = p->ops;
2177
2178	parport_remove_port(p);
2179	if (p->modes & PARPORT_MODE_DMA)
2180		parport_ip32_dma_unregister();
2181	if (p->irq != PARPORT_IRQ_NONE)
2182		free_irq(p->irq, p);
2183	parport_put_port(p);
2184	kfree(priv);
2185	kfree(ops);
2186}
2187
2188/**
2189 * parport_ip32_init - module initialization function
2190 */
2191static int __init parport_ip32_init(void)
2192{
2193	pr_info(PPIP32 "SGI IP32 built-in parallel port driver v0.6\n");
2194	this_port = parport_ip32_probe_port();
2195	return PTR_ERR_OR_ZERO(this_port);
2196}
2197
2198/**
2199 * parport_ip32_exit - module termination function
2200 */
2201static void __exit parport_ip32_exit(void)
2202{
2203	parport_ip32_unregister_port(this_port);
2204}
2205
2206/*--- Module stuff -----------------------------------------------------*/
2207
2208MODULE_AUTHOR("Arnaud Giersch <arnaud.giersch@free.fr>");
2209MODULE_DESCRIPTION("SGI IP32 built-in parallel port driver");
2210MODULE_LICENSE("GPL");
2211MODULE_VERSION("0.6");		/* update in parport_ip32_init() too */
2212
2213module_init(parport_ip32_init);
2214module_exit(parport_ip32_exit);
2215
2216module_param(verbose_probing, bool, S_IRUGO);
2217MODULE_PARM_DESC(verbose_probing, "Log chit-chat during initialization");
2218
2219module_param(features, uint, S_IRUGO);
2220MODULE_PARM_DESC(features,
2221		 "Bit mask of features to enable"
2222		 ", bit 0: IRQ support"
2223		 ", bit 1: DMA support"
2224		 ", bit 2: hardware SPP mode"
2225		 ", bit 3: hardware EPP mode"
2226		 ", bit 4: hardware ECP mode");
2227