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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6/arch/arm/mach-ixp4xx/
1/*
2 * arch/arm/mach-ixp4xx/common-pci.c
3 *
4 * IXP4XX PCI routines for all platforms
5 *
6 * Maintainer: Deepak Saxena <dsaxena@plexity.net>
7 *
8 * Copyright (C) 2002 Intel Corporation.
9 * Copyright (C) 2003 Greg Ungerer <gerg@snapgear.com>
10 * Copyright (C) 2003-2004 MontaVista Software, Inc.
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License version 2 as
14 * published by the Free Software Foundation.
15 *
16 */
17
18#include <linux/sched.h>
19#include <linux/kernel.h>
20#include <linux/pci.h>
21#include <linux/interrupt.h>
22#include <linux/mm.h>
23#include <linux/init.h>
24#include <linux/ioport.h>
25#include <linux/slab.h>
26#include <linux/delay.h>
27#include <linux/device.h>
28#include <linux/io.h>
29#include <asm/dma-mapping.h>
30
31#include <asm/cputype.h>
32#include <asm/irq.h>
33#include <asm/sizes.h>
34#include <asm/system.h>
35#include <asm/mach/pci.h>
36#include <mach/hardware.h>
37
38
39/*
40 * IXP4xx PCI read function is dependent on whether we are
41 * running A0 or B0 (AppleGate) silicon.
42 */
43int (*ixp4xx_pci_read)(u32 addr, u32 cmd, u32* data);
44
45/*
46 * Base address for PCI regsiter region
47 */
48unsigned long ixp4xx_pci_reg_base = 0;
49
50/*
51 * PCI cfg an I/O routines are done by programming a
52 * command/byte enable register, and then read/writing
53 * the data from a data regsiter. We need to ensure
54 * these transactions are atomic or we will end up
55 * with corrupt data on the bus or in a driver.
56 */
57static DEFINE_SPINLOCK(ixp4xx_pci_lock);
58
59/*
60 * Read from PCI config space
61 */
62static void crp_read(u32 ad_cbe, u32 *data)
63{
64	unsigned long flags;
65	spin_lock_irqsave(&ixp4xx_pci_lock, flags);
66	*PCI_CRP_AD_CBE = ad_cbe;
67	*data = *PCI_CRP_RDATA;
68	spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
69}
70
71/*
72 * Write to PCI config space
73 */
74static void crp_write(u32 ad_cbe, u32 data)
75{
76	unsigned long flags;
77	spin_lock_irqsave(&ixp4xx_pci_lock, flags);
78	*PCI_CRP_AD_CBE = CRP_AD_CBE_WRITE | ad_cbe;
79	*PCI_CRP_WDATA = data;
80	spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
81}
82
83static inline int check_master_abort(void)
84{
85	/* check Master Abort bit after access */
86	unsigned long isr = *PCI_ISR;
87
88	if (isr & PCI_ISR_PFE) {
89		/* make sure the Master Abort bit is reset */
90		*PCI_ISR = PCI_ISR_PFE;
91		pr_debug("%s failed\n", __func__);
92		return 1;
93	}
94
95	return 0;
96}
97
98int ixp4xx_pci_read_errata(u32 addr, u32 cmd, u32* data)
99{
100	unsigned long flags;
101	int retval = 0;
102	int i;
103
104	spin_lock_irqsave(&ixp4xx_pci_lock, flags);
105
106	*PCI_NP_AD = addr;
107
108	for (i = 0; i < 8; i++) {
109		*PCI_NP_CBE = cmd;
110		*data = *PCI_NP_RDATA;
111		*data = *PCI_NP_RDATA;
112	}
113
114	if(check_master_abort())
115		retval = 1;
116
117	spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
118	return retval;
119}
120
121int ixp4xx_pci_read_no_errata(u32 addr, u32 cmd, u32* data)
122{
123	unsigned long flags;
124	int retval = 0;
125
126	spin_lock_irqsave(&ixp4xx_pci_lock, flags);
127
128	*PCI_NP_AD = addr;
129
130	/* set up and execute the read */
131	*PCI_NP_CBE = cmd;
132
133	/* the result of the read is now in NP_RDATA */
134	*data = *PCI_NP_RDATA;
135
136	if(check_master_abort())
137		retval = 1;
138
139	spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
140	return retval;
141}
142
143int ixp4xx_pci_write(u32 addr, u32 cmd, u32 data)
144{
145	unsigned long flags;
146	int retval = 0;
147
148	spin_lock_irqsave(&ixp4xx_pci_lock, flags);
149
150	*PCI_NP_AD = addr;
151
152	/* set up the write */
153	*PCI_NP_CBE = cmd;
154
155	/* execute the write by writing to NP_WDATA */
156	*PCI_NP_WDATA = data;
157
158	if(check_master_abort())
159		retval = 1;
160
161	spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
162	return retval;
163}
164
165static u32 ixp4xx_config_addr(u8 bus_num, u16 devfn, int where)
166{
167	u32 addr;
168	if (!bus_num) {
169		/* type 0 */
170		addr = BIT(32-PCI_SLOT(devfn)) | ((PCI_FUNC(devfn)) << 8) |
171		    (where & ~3);
172	} else {
173		/* type 1 */
174		addr = (bus_num << 16) | ((PCI_SLOT(devfn)) << 11) |
175			((PCI_FUNC(devfn)) << 8) | (where & ~3) | 1;
176	}
177	return addr;
178}
179
180/*
181 * Mask table, bits to mask for quantity of size 1, 2 or 4 bytes.
182 * 0 and 3 are not valid indexes...
183 */
184static u32 bytemask[] = {
185	/*0*/	0,
186	/*1*/	0xff,
187	/*2*/	0xffff,
188	/*3*/	0,
189	/*4*/	0xffffffff,
190};
191
192static u32 local_byte_lane_enable_bits(u32 n, int size)
193{
194	if (size == 1)
195		return (0xf & ~BIT(n)) << CRP_AD_CBE_BESL;
196	if (size == 2)
197		return (0xf & ~(BIT(n) | BIT(n+1))) << CRP_AD_CBE_BESL;
198	if (size == 4)
199		return 0;
200	return 0xffffffff;
201}
202
203static int local_read_config(int where, int size, u32 *value)
204{
205	u32 n, data;
206	pr_debug("local_read_config from %d size %d\n", where, size);
207	n = where % 4;
208	crp_read(where & ~3, &data);
209	*value = (data >> (8*n)) & bytemask[size];
210	pr_debug("local_read_config read %#x\n", *value);
211	return PCIBIOS_SUCCESSFUL;
212}
213
214static int local_write_config(int where, int size, u32 value)
215{
216	u32 n, byte_enables, data;
217	pr_debug("local_write_config %#x to %d size %d\n", value, where, size);
218	n = where % 4;
219	byte_enables = local_byte_lane_enable_bits(n, size);
220	if (byte_enables == 0xffffffff)
221		return PCIBIOS_BAD_REGISTER_NUMBER;
222	data = value << (8*n);
223	crp_write((where & ~3) | byte_enables, data);
224	return PCIBIOS_SUCCESSFUL;
225}
226
227static u32 byte_lane_enable_bits(u32 n, int size)
228{
229	if (size == 1)
230		return (0xf & ~BIT(n)) << 4;
231	if (size == 2)
232		return (0xf & ~(BIT(n) | BIT(n+1))) << 4;
233	if (size == 4)
234		return 0;
235	return 0xffffffff;
236}
237
238static int ixp4xx_pci_read_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *value)
239{
240	u32 n, byte_enables, addr, data;
241	u8 bus_num = bus->number;
242
243	pr_debug("read_config from %d size %d dev %d:%d:%d\n", where, size,
244		bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn));
245
246	*value = 0xffffffff;
247	n = where % 4;
248	byte_enables = byte_lane_enable_bits(n, size);
249	if (byte_enables == 0xffffffff)
250		return PCIBIOS_BAD_REGISTER_NUMBER;
251
252	addr = ixp4xx_config_addr(bus_num, devfn, where);
253	if (ixp4xx_pci_read(addr, byte_enables | NP_CMD_CONFIGREAD, &data))
254		return PCIBIOS_DEVICE_NOT_FOUND;
255
256	*value = (data >> (8*n)) & bytemask[size];
257	pr_debug("read_config_byte read %#x\n", *value);
258	return PCIBIOS_SUCCESSFUL;
259}
260
261static int ixp4xx_pci_write_config(struct pci_bus *bus,  unsigned int devfn, int where, int size, u32 value)
262{
263	u32 n, byte_enables, addr, data;
264	u8 bus_num = bus->number;
265
266	pr_debug("write_config_byte %#x to %d size %d dev %d:%d:%d\n", value, where,
267		size, bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn));
268
269	n = where % 4;
270	byte_enables = byte_lane_enable_bits(n, size);
271	if (byte_enables == 0xffffffff)
272		return PCIBIOS_BAD_REGISTER_NUMBER;
273
274	addr = ixp4xx_config_addr(bus_num, devfn, where);
275	data = value << (8*n);
276	if (ixp4xx_pci_write(addr, byte_enables | NP_CMD_CONFIGWRITE, data))
277		return PCIBIOS_DEVICE_NOT_FOUND;
278
279	return PCIBIOS_SUCCESSFUL;
280}
281
282struct pci_ops ixp4xx_ops = {
283	.read =  ixp4xx_pci_read_config,
284	.write = ixp4xx_pci_write_config,
285};
286
287/*
288 * PCI abort handler
289 */
290static int abort_handler(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
291{
292	u32 isr, status;
293
294	isr = *PCI_ISR;
295	local_read_config(PCI_STATUS, 2, &status);
296	pr_debug("PCI: abort_handler addr = %#lx, isr = %#x, "
297		"status = %#x\n", addr, isr, status);
298
299	/* make sure the Master Abort bit is reset */
300	*PCI_ISR = PCI_ISR_PFE;
301	status |= PCI_STATUS_REC_MASTER_ABORT;
302	local_write_config(PCI_STATUS, 2, status);
303
304	/*
305	 * If it was an imprecise abort, then we need to correct the
306	 * return address to be _after_ the instruction.
307	 */
308	if (fsr & (1 << 10))
309		regs->ARM_pc += 4;
310
311	return 0;
312}
313
314
315/*
316 * Setup DMA mask to 64MB on PCI devices. Ignore all other devices.
317 */
318static int ixp4xx_pci_platform_notify(struct device *dev)
319{
320	if(dev->bus == &pci_bus_type) {
321		*dev->dma_mask =  SZ_64M - 1;
322		dev->coherent_dma_mask = SZ_64M - 1;
323		dmabounce_register_dev(dev, 2048, 4096);
324	}
325	return 0;
326}
327
328static int ixp4xx_pci_platform_notify_remove(struct device *dev)
329{
330	if(dev->bus == &pci_bus_type) {
331		dmabounce_unregister_dev(dev);
332	}
333	return 0;
334}
335
336int dma_needs_bounce(struct device *dev, dma_addr_t dma_addr, size_t size)
337{
338	return (dev->bus == &pci_bus_type ) && ((dma_addr + size) >= SZ_64M);
339}
340
341/*
342 * Only first 64MB of memory can be accessed via PCI.
343 * We use GFP_DMA to allocate safe buffers to do map/unmap.
344 * This is really ugly and we need a better way of specifying
345 * DMA-capable regions of memory.
346 */
347void __init ixp4xx_adjust_zones(unsigned long *zone_size,
348	unsigned long *zhole_size)
349{
350	unsigned int sz = SZ_64M >> PAGE_SHIFT;
351
352	/*
353	 * Only adjust if > 64M on current system
354	 */
355	if (zone_size[0] <= sz)
356		return;
357
358	zone_size[1] = zone_size[0] - sz;
359	zone_size[0] = sz;
360	zhole_size[1] = zhole_size[0];
361	zhole_size[0] = 0;
362}
363
364void __init ixp4xx_pci_preinit(void)
365{
366	unsigned long cpuid = read_cpuid_id();
367
368	if (!(cpuid & 0xf) && cpu_is_ixp42x()) {
369		printk("PCI: IXP42x A0 silicon detected - "
370			"PCI Non-Prefetch Workaround Enabled\n");
371		ixp4xx_pci_read = ixp4xx_pci_read_errata;
372	} else
373		ixp4xx_pci_read = ixp4xx_pci_read_no_errata;
374
375
376	/* hook in our fault handler for PCI errors */
377	hook_fault_code(16+6, abort_handler, SIGBUS, 0,
378			"imprecise external abort");
379
380	pr_debug("setup PCI-AHB(inbound) and AHB-PCI(outbound) address mappings\n");
381
382	/*
383	 * We use identity AHB->PCI address translation
384	 * in the 0x48000000 to 0x4bffffff address space
385	 */
386	*PCI_PCIMEMBASE = 0x48494A4B;
387
388	/*
389	 * We also use identity PCI->AHB address translation
390	 * in 4 16MB BARs that begin at the physical memory start
391	 */
392	*PCI_AHBMEMBASE = (PHYS_OFFSET & 0xFF000000) +
393		((PHYS_OFFSET & 0xFF000000) >> 8) +
394		((PHYS_OFFSET & 0xFF000000) >> 16) +
395		((PHYS_OFFSET & 0xFF000000) >> 24) +
396		0x00010203;
397
398	if (*PCI_CSR & PCI_CSR_HOST) {
399		printk("PCI: IXP4xx is host\n");
400
401		pr_debug("setup BARs in controller\n");
402
403		/*
404		 * We configure the PCI inbound memory windows to be
405		 * 1:1 mapped to SDRAM
406		 */
407		local_write_config(PCI_BASE_ADDRESS_0, 4, PHYS_OFFSET);
408		local_write_config(PCI_BASE_ADDRESS_1, 4, PHYS_OFFSET + SZ_16M);
409		local_write_config(PCI_BASE_ADDRESS_2, 4, PHYS_OFFSET + SZ_32M);
410		local_write_config(PCI_BASE_ADDRESS_3, 4, PHYS_OFFSET + SZ_48M);
411
412		/*
413		 * Enable CSR window at 64 MiB to allow PCI masters
414		 * to continue prefetching past 64 MiB boundary.
415		 */
416		local_write_config(PCI_BASE_ADDRESS_4, 4, PHYS_OFFSET + SZ_64M);
417
418		/*
419		 * Enable the IO window to be way up high, at 0xfffffc00
420		 */
421		local_write_config(PCI_BASE_ADDRESS_5, 4, 0xfffffc01);
422	} else {
423		printk("PCI: IXP4xx is target - No bus scan performed\n");
424	}
425
426	printk("PCI: IXP4xx Using %s access for memory space\n",
427#ifndef CONFIG_IXP4XX_INDIRECT_PCI
428			"direct"
429#else
430			"indirect"
431#endif
432		);
433
434	pr_debug("clear error bits in ISR\n");
435	*PCI_ISR = PCI_ISR_PSE | PCI_ISR_PFE | PCI_ISR_PPE | PCI_ISR_AHBE;
436
437	/*
438	 * Set Initialize Complete in PCI Control Register: allow IXP4XX to
439	 * respond to PCI configuration cycles. Specify that the AHB bus is
440	 * operating in big endian mode. Set up byte lane swapping between
441	 * little-endian PCI and the big-endian AHB bus
442	 */
443#ifdef __ARMEB__
444	*PCI_CSR = PCI_CSR_IC | PCI_CSR_ABE | PCI_CSR_PDS | PCI_CSR_ADS;
445#else
446	*PCI_CSR = PCI_CSR_IC | PCI_CSR_ABE;
447#endif
448
449	pr_debug("DONE\n");
450}
451
452int ixp4xx_setup(int nr, struct pci_sys_data *sys)
453{
454	struct resource *res;
455
456	if (nr >= 1)
457		return 0;
458
459	res = kzalloc(sizeof(*res) * 2, GFP_KERNEL);
460	if (res == NULL) {
461		/*
462		 * If we're out of memory this early, something is wrong,
463		 * so we might as well catch it here.
464		 */
465		panic("PCI: unable to allocate resources?\n");
466	}
467
468	local_write_config(PCI_COMMAND, 2, PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY);
469
470	res[0].name = "PCI I/O Space";
471	res[0].start = 0x00000000;
472	res[0].end = 0x0000ffff;
473	res[0].flags = IORESOURCE_IO;
474
475	res[1].name = "PCI Memory Space";
476	res[1].start = PCIBIOS_MIN_MEM;
477	res[1].end = PCIBIOS_MAX_MEM;
478	res[1].flags = IORESOURCE_MEM;
479
480	request_resource(&ioport_resource, &res[0]);
481	request_resource(&iomem_resource, &res[1]);
482
483	sys->resource[0] = &res[0];
484	sys->resource[1] = &res[1];
485	sys->resource[2] = NULL;
486
487	platform_notify = ixp4xx_pci_platform_notify;
488	platform_notify_remove = ixp4xx_pci_platform_notify_remove;
489
490	return 1;
491}
492
493struct pci_bus * __devinit ixp4xx_scan_bus(int nr, struct pci_sys_data *sys)
494{
495	return pci_scan_bus(sys->busnr, &ixp4xx_ops, sys);
496}
497
498int dma_set_coherent_mask(struct device *dev, u64 mask)
499{
500	if (mask >= SZ_64M - 1)
501		return 0;
502
503	return -EIO;
504}
505
506EXPORT_SYMBOL(ixp4xx_pci_read);
507EXPORT_SYMBOL(ixp4xx_pci_write);
508