1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright (C) 2018 Oleksij Rempel <linux@rempel-privat.de>
4 *
5 * Driver for Alcor Micro AU6601 and AU6621 controllers
6 */
7
8/* Note: this driver was created without any documentation. Based
9 * on sniffing, testing and in some cases mimic of original driver.
10 * As soon as some one with documentation or more experience in SD/MMC, or
11 * reverse engineering then me, please review this driver and question every
12 * thing what I did. 2018 Oleksij Rempel <linux@rempel-privat.de>
13 */
14
15#include <linux/delay.h>
16#include <linux/pci.h>
17#include <linux/module.h>
18#include <linux/io.h>
19#include <linux/pm.h>
20#include <linux/irq.h>
21#include <linux/interrupt.h>
22#include <linux/platform_device.h>
23
24#include <linux/mmc/host.h>
25#include <linux/mmc/mmc.h>
26
27#include <linux/alcor_pci.h>
28
29enum alcor_cookie {
30	COOKIE_UNMAPPED,
31	COOKIE_PRE_MAPPED,
32	COOKIE_MAPPED,
33};
34
35struct alcor_pll_conf {
36	unsigned int clk_src_freq;
37	unsigned int clk_src_reg;
38	unsigned int min_div;
39	unsigned int max_div;
40};
41
42struct alcor_sdmmc_host {
43	struct  device *dev;
44	struct alcor_pci_priv *alcor_pci;
45
46	struct mmc_request *mrq;
47	struct mmc_command *cmd;
48	struct mmc_data *data;
49	unsigned int dma_on:1;
50
51	struct mutex cmd_mutex;
52
53	struct delayed_work timeout_work;
54
55	struct sg_mapping_iter sg_miter;	/* SG state for PIO */
56	struct scatterlist *sg;
57	unsigned int blocks;		/* remaining PIO blocks */
58	int sg_count;
59
60	u32			irq_status_sd;
61	unsigned char		cur_power_mode;
62};
63
64static const struct alcor_pll_conf alcor_pll_cfg[] = {
65	/* MHZ,		CLK src,		max div, min div */
66	{ 31250000,	AU6601_CLK_31_25_MHZ,	1,	511},
67	{ 48000000,	AU6601_CLK_48_MHZ,	1,	511},
68	{125000000,	AU6601_CLK_125_MHZ,	1,	511},
69	{384000000,	AU6601_CLK_384_MHZ,	1,	511},
70};
71
72static inline void alcor_rmw8(struct alcor_sdmmc_host *host, unsigned int addr,
73			       u8 clear, u8 set)
74{
75	struct alcor_pci_priv *priv = host->alcor_pci;
76	u32 var;
77
78	var = alcor_read8(priv, addr);
79	var &= ~clear;
80	var |= set;
81	alcor_write8(priv, var, addr);
82}
83
84/* As soon as irqs are masked, some status updates may be missed.
85 * Use this with care.
86 */
87static inline void alcor_mask_sd_irqs(struct alcor_sdmmc_host *host)
88{
89	struct alcor_pci_priv *priv = host->alcor_pci;
90
91	alcor_write32(priv, 0, AU6601_REG_INT_ENABLE);
92}
93
94static inline void alcor_unmask_sd_irqs(struct alcor_sdmmc_host *host)
95{
96	struct alcor_pci_priv *priv = host->alcor_pci;
97
98	alcor_write32(priv, AU6601_INT_CMD_MASK | AU6601_INT_DATA_MASK |
99		  AU6601_INT_CARD_INSERT | AU6601_INT_CARD_REMOVE |
100		  AU6601_INT_OVER_CURRENT_ERR,
101		  AU6601_REG_INT_ENABLE);
102}
103
104static void alcor_reset(struct alcor_sdmmc_host *host, u8 val)
105{
106	struct alcor_pci_priv *priv = host->alcor_pci;
107	int i;
108
109	alcor_write8(priv, val | AU6601_BUF_CTRL_RESET,
110		      AU6601_REG_SW_RESET);
111	for (i = 0; i < 100; i++) {
112		if (!(alcor_read8(priv, AU6601_REG_SW_RESET) & val))
113			return;
114		udelay(50);
115	}
116	dev_err(host->dev, "%s: timeout\n", __func__);
117}
118
119/*
120 * Perform DMA I/O of a single page.
121 */
122static void alcor_data_set_dma(struct alcor_sdmmc_host *host)
123{
124	struct alcor_pci_priv *priv = host->alcor_pci;
125	u32 addr;
126
127	if (!host->sg_count)
128		return;
129
130	if (!host->sg) {
131		dev_err(host->dev, "have blocks, but no SG\n");
132		return;
133	}
134
135	if (!sg_dma_len(host->sg)) {
136		dev_err(host->dev, "DMA SG len == 0\n");
137		return;
138	}
139
140
141	addr = (u32)sg_dma_address(host->sg);
142
143	alcor_write32(priv, addr, AU6601_REG_SDMA_ADDR);
144	host->sg = sg_next(host->sg);
145	host->sg_count--;
146}
147
148static void alcor_trigger_data_transfer(struct alcor_sdmmc_host *host)
149{
150	struct alcor_pci_priv *priv = host->alcor_pci;
151	struct mmc_data *data = host->data;
152	u8 ctrl = 0;
153
154	if (data->flags & MMC_DATA_WRITE)
155		ctrl |= AU6601_DATA_WRITE;
156
157	if (data->host_cookie == COOKIE_MAPPED) {
158		/*
159		 * For DMA transfers, this function is called just once,
160		 * at the start of the operation. The hardware can only
161		 * perform DMA I/O on a single page at a time, so here
162		 * we kick off the transfer with the first page, and expect
163		 * subsequent pages to be transferred upon IRQ events
164		 * indicating that the single-page DMA was completed.
165		 */
166		alcor_data_set_dma(host);
167		ctrl |= AU6601_DATA_DMA_MODE;
168		host->dma_on = 1;
169		alcor_write32(priv, data->sg_count * 0x1000,
170			       AU6601_REG_BLOCK_SIZE);
171	} else {
172		/*
173		 * For PIO transfers, we break down each operation
174		 * into several sector-sized transfers. When one sector has
175		 * complete, the IRQ handler will call this function again
176		 * to kick off the transfer of the next sector.
177		 */
178		alcor_write32(priv, data->blksz, AU6601_REG_BLOCK_SIZE);
179	}
180
181	alcor_write8(priv, ctrl | AU6601_DATA_START_XFER,
182		      AU6601_DATA_XFER_CTRL);
183}
184
185static void alcor_trf_block_pio(struct alcor_sdmmc_host *host, bool read)
186{
187	struct alcor_pci_priv *priv = host->alcor_pci;
188	size_t blksize, len;
189	u8 *buf;
190
191	if (!host->blocks)
192		return;
193
194	if (host->dma_on) {
195		dev_err(host->dev, "configured DMA but got PIO request.\n");
196		return;
197	}
198
199	if (!!(host->data->flags & MMC_DATA_READ) != read) {
200		dev_err(host->dev, "got unexpected direction %i != %i\n",
201			!!(host->data->flags & MMC_DATA_READ), read);
202	}
203
204	if (!sg_miter_next(&host->sg_miter))
205		return;
206
207	blksize = host->data->blksz;
208	len = min(host->sg_miter.length, blksize);
209
210	dev_dbg(host->dev, "PIO, %s block size: 0x%zx\n",
211		read ? "read" : "write", blksize);
212
213	host->sg_miter.consumed = len;
214	host->blocks--;
215
216	buf = host->sg_miter.addr;
217
218	if (read)
219		ioread32_rep(priv->iobase + AU6601_REG_BUFFER, buf, len >> 2);
220	else
221		iowrite32_rep(priv->iobase + AU6601_REG_BUFFER, buf, len >> 2);
222
223	sg_miter_stop(&host->sg_miter);
224}
225
226static void alcor_prepare_sg_miter(struct alcor_sdmmc_host *host)
227{
228	unsigned int flags = SG_MITER_ATOMIC;
229	struct mmc_data *data = host->data;
230
231	if (data->flags & MMC_DATA_READ)
232		flags |= SG_MITER_TO_SG;
233	else
234		flags |= SG_MITER_FROM_SG;
235	sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags);
236}
237
238static void alcor_prepare_data(struct alcor_sdmmc_host *host,
239			       struct mmc_command *cmd)
240{
241	struct alcor_pci_priv *priv = host->alcor_pci;
242	struct mmc_data *data = cmd->data;
243
244	if (!data)
245		return;
246
247
248	host->data = data;
249	host->data->bytes_xfered = 0;
250	host->blocks = data->blocks;
251	host->sg = data->sg;
252	host->sg_count = data->sg_count;
253	dev_dbg(host->dev, "prepare DATA: sg %i, blocks: %i\n",
254			host->sg_count, host->blocks);
255
256	if (data->host_cookie != COOKIE_MAPPED)
257		alcor_prepare_sg_miter(host);
258
259	alcor_write8(priv, 0, AU6601_DATA_XFER_CTRL);
260}
261
262static void alcor_send_cmd(struct alcor_sdmmc_host *host,
263			   struct mmc_command *cmd, bool set_timeout)
264{
265	struct alcor_pci_priv *priv = host->alcor_pci;
266	unsigned long timeout = 0;
267	u8 ctrl = 0;
268
269	host->cmd = cmd;
270	alcor_prepare_data(host, cmd);
271
272	dev_dbg(host->dev, "send CMD. opcode: 0x%02x, arg; 0x%08x\n",
273		cmd->opcode, cmd->arg);
274	alcor_write8(priv, cmd->opcode | 0x40, AU6601_REG_CMD_OPCODE);
275	alcor_write32be(priv, cmd->arg, AU6601_REG_CMD_ARG);
276
277	switch (mmc_resp_type(cmd)) {
278	case MMC_RSP_NONE:
279		ctrl = AU6601_CMD_NO_RESP;
280		break;
281	case MMC_RSP_R1:
282		ctrl = AU6601_CMD_6_BYTE_CRC;
283		break;
284	case MMC_RSP_R1B:
285		ctrl = AU6601_CMD_6_BYTE_CRC | AU6601_CMD_STOP_WAIT_RDY;
286		break;
287	case MMC_RSP_R2:
288		ctrl = AU6601_CMD_17_BYTE_CRC;
289		break;
290	case MMC_RSP_R3:
291		ctrl = AU6601_CMD_6_BYTE_WO_CRC;
292		break;
293	default:
294		dev_err(host->dev, "%s: cmd->flag (0x%02x) is not valid\n",
295			mmc_hostname(mmc_from_priv(host)), mmc_resp_type(cmd));
296		break;
297	}
298
299	if (set_timeout) {
300		if (!cmd->data && cmd->busy_timeout)
301			timeout = cmd->busy_timeout;
302		else
303			timeout = 10000;
304
305		schedule_delayed_work(&host->timeout_work,
306				      msecs_to_jiffies(timeout));
307	}
308
309	dev_dbg(host->dev, "xfer ctrl: 0x%02x; timeout: %lu\n", ctrl, timeout);
310	alcor_write8(priv, ctrl | AU6601_CMD_START_XFER,
311				 AU6601_CMD_XFER_CTRL);
312}
313
314static void alcor_request_complete(struct alcor_sdmmc_host *host,
315				   bool cancel_timeout)
316{
317	struct mmc_request *mrq;
318
319	/*
320	 * If this work gets rescheduled while running, it will
321	 * be run again afterwards but without any active request.
322	 */
323	if (!host->mrq)
324		return;
325
326	if (cancel_timeout)
327		cancel_delayed_work(&host->timeout_work);
328
329	mrq = host->mrq;
330
331	host->mrq = NULL;
332	host->cmd = NULL;
333	host->data = NULL;
334	host->dma_on = 0;
335
336	mmc_request_done(mmc_from_priv(host), mrq);
337}
338
339static void alcor_finish_data(struct alcor_sdmmc_host *host)
340{
341	struct mmc_data *data;
342
343	data = host->data;
344	host->data = NULL;
345	host->dma_on = 0;
346
347	/*
348	 * The specification states that the block count register must
349	 * be updated, but it does not specify at what point in the
350	 * data flow. That makes the register entirely useless to read
351	 * back so we have to assume that nothing made it to the card
352	 * in the event of an error.
353	 */
354	if (data->error)
355		data->bytes_xfered = 0;
356	else
357		data->bytes_xfered = data->blksz * data->blocks;
358
359	/*
360	 * Need to send CMD12 if -
361	 * a) open-ended multiblock transfer (no CMD23)
362	 * b) error in multiblock transfer
363	 */
364	if (data->stop &&
365	    (data->error ||
366	     !host->mrq->sbc)) {
367
368		/*
369		 * The controller needs a reset of internal state machines
370		 * upon error conditions.
371		 */
372		if (data->error)
373			alcor_reset(host, AU6601_RESET_CMD | AU6601_RESET_DATA);
374
375		alcor_unmask_sd_irqs(host);
376		alcor_send_cmd(host, data->stop, false);
377		return;
378	}
379
380	alcor_request_complete(host, 1);
381}
382
383static void alcor_err_irq(struct alcor_sdmmc_host *host, u32 intmask)
384{
385	dev_dbg(host->dev, "ERR IRQ %x\n", intmask);
386
387	if (host->cmd) {
388		if (intmask & AU6601_INT_CMD_TIMEOUT_ERR)
389			host->cmd->error = -ETIMEDOUT;
390		else
391			host->cmd->error = -EILSEQ;
392	}
393
394	if (host->data) {
395		if (intmask & AU6601_INT_DATA_TIMEOUT_ERR)
396			host->data->error = -ETIMEDOUT;
397		else
398			host->data->error = -EILSEQ;
399
400		host->data->bytes_xfered = 0;
401	}
402
403	alcor_reset(host, AU6601_RESET_CMD | AU6601_RESET_DATA);
404	alcor_request_complete(host, 1);
405}
406
407static int alcor_cmd_irq_done(struct alcor_sdmmc_host *host, u32 intmask)
408{
409	struct alcor_pci_priv *priv = host->alcor_pci;
410
411	intmask &= AU6601_INT_CMD_END;
412
413	if (!intmask)
414		return true;
415
416	/* got CMD_END but no CMD is in progress, wake thread an process the
417	 * error
418	 */
419	if (!host->cmd)
420		return false;
421
422	if (host->cmd->flags & MMC_RSP_PRESENT) {
423		struct mmc_command *cmd = host->cmd;
424
425		cmd->resp[0] = alcor_read32be(priv, AU6601_REG_CMD_RSP0);
426		dev_dbg(host->dev, "RSP0: 0x%04x\n", cmd->resp[0]);
427		if (host->cmd->flags & MMC_RSP_136) {
428			cmd->resp[1] =
429				alcor_read32be(priv, AU6601_REG_CMD_RSP1);
430			cmd->resp[2] =
431				alcor_read32be(priv, AU6601_REG_CMD_RSP2);
432			cmd->resp[3] =
433				alcor_read32be(priv, AU6601_REG_CMD_RSP3);
434			dev_dbg(host->dev, "RSP1,2,3: 0x%04x 0x%04x 0x%04x\n",
435				cmd->resp[1], cmd->resp[2], cmd->resp[3]);
436		}
437
438	}
439
440	host->cmd->error = 0;
441
442	/* Processed actual command. */
443	if (!host->data)
444		return false;
445
446	alcor_trigger_data_transfer(host);
447	host->cmd = NULL;
448	return true;
449}
450
451static void alcor_cmd_irq_thread(struct alcor_sdmmc_host *host, u32 intmask)
452{
453	intmask &= AU6601_INT_CMD_END;
454
455	if (!intmask)
456		return;
457
458	if (!host->cmd && intmask & AU6601_INT_CMD_END) {
459		dev_dbg(host->dev, "Got command interrupt 0x%08x even though no command operation was in progress.\n",
460			intmask);
461	}
462
463	/* Processed actual command. */
464	if (!host->data)
465		alcor_request_complete(host, 1);
466	else
467		alcor_trigger_data_transfer(host);
468	host->cmd = NULL;
469}
470
471static int alcor_data_irq_done(struct alcor_sdmmc_host *host, u32 intmask)
472{
473	u32 tmp;
474
475	intmask &= AU6601_INT_DATA_MASK;
476
477	/* nothing here to do */
478	if (!intmask)
479		return 1;
480
481	/* we was too fast and got DATA_END after it was processed?
482	 * lets ignore it for now.
483	 */
484	if (!host->data && intmask == AU6601_INT_DATA_END)
485		return 1;
486
487	/* looks like an error, so lets handle it. */
488	if (!host->data)
489		return 0;
490
491	tmp = intmask & (AU6601_INT_READ_BUF_RDY | AU6601_INT_WRITE_BUF_RDY
492			 | AU6601_INT_DMA_END);
493	switch (tmp) {
494	case 0:
495		break;
496	case AU6601_INT_READ_BUF_RDY:
497		alcor_trf_block_pio(host, true);
498		return 1;
499	case AU6601_INT_WRITE_BUF_RDY:
500		alcor_trf_block_pio(host, false);
501		return 1;
502	case AU6601_INT_DMA_END:
503		if (!host->sg_count)
504			break;
505
506		alcor_data_set_dma(host);
507		break;
508	default:
509		dev_err(host->dev, "Got READ_BUF_RDY and WRITE_BUF_RDY at same time\n");
510		break;
511	}
512
513	if (intmask & AU6601_INT_DATA_END) {
514		if (!host->dma_on && host->blocks) {
515			alcor_trigger_data_transfer(host);
516			return 1;
517		} else {
518			return 0;
519		}
520	}
521
522	return 1;
523}
524
525static void alcor_data_irq_thread(struct alcor_sdmmc_host *host, u32 intmask)
526{
527	intmask &= AU6601_INT_DATA_MASK;
528
529	if (!intmask)
530		return;
531
532	if (!host->data) {
533		dev_dbg(host->dev, "Got data interrupt 0x%08x even though no data operation was in progress.\n",
534			intmask);
535		alcor_reset(host, AU6601_RESET_DATA);
536		return;
537	}
538
539	if (alcor_data_irq_done(host, intmask))
540		return;
541
542	if ((intmask & AU6601_INT_DATA_END) || !host->blocks ||
543	    (host->dma_on && !host->sg_count))
544		alcor_finish_data(host);
545}
546
547static void alcor_cd_irq(struct alcor_sdmmc_host *host, u32 intmask)
548{
549	dev_dbg(host->dev, "card %s\n",
550		intmask & AU6601_INT_CARD_REMOVE ? "removed" : "inserted");
551
552	if (host->mrq) {
553		dev_dbg(host->dev, "cancel all pending tasks.\n");
554
555		if (host->data)
556			host->data->error = -ENOMEDIUM;
557
558		if (host->cmd)
559			host->cmd->error = -ENOMEDIUM;
560		else
561			host->mrq->cmd->error = -ENOMEDIUM;
562
563		alcor_request_complete(host, 1);
564	}
565
566	mmc_detect_change(mmc_from_priv(host), msecs_to_jiffies(1));
567}
568
569static irqreturn_t alcor_irq_thread(int irq, void *d)
570{
571	struct alcor_sdmmc_host *host = d;
572	irqreturn_t ret = IRQ_HANDLED;
573	u32 intmask, tmp;
574
575	mutex_lock(&host->cmd_mutex);
576
577	intmask = host->irq_status_sd;
578
579	/* some thing bad */
580	if (unlikely(!intmask || AU6601_INT_ALL_MASK == intmask)) {
581		dev_dbg(host->dev, "unexpected IRQ: 0x%04x\n", intmask);
582		ret = IRQ_NONE;
583		goto exit;
584	}
585
586	tmp = intmask & (AU6601_INT_CMD_MASK | AU6601_INT_DATA_MASK);
587	if (tmp) {
588		if (tmp & AU6601_INT_ERROR_MASK)
589			alcor_err_irq(host, tmp);
590		else {
591			alcor_cmd_irq_thread(host, tmp);
592			alcor_data_irq_thread(host, tmp);
593		}
594		intmask &= ~(AU6601_INT_CMD_MASK | AU6601_INT_DATA_MASK);
595	}
596
597	if (intmask & (AU6601_INT_CARD_INSERT | AU6601_INT_CARD_REMOVE)) {
598		alcor_cd_irq(host, intmask);
599		intmask &= ~(AU6601_INT_CARD_INSERT | AU6601_INT_CARD_REMOVE);
600	}
601
602	if (intmask & AU6601_INT_OVER_CURRENT_ERR) {
603		dev_warn(host->dev,
604			 "warning: over current detected!\n");
605		intmask &= ~AU6601_INT_OVER_CURRENT_ERR;
606	}
607
608	if (intmask)
609		dev_dbg(host->dev, "got not handled IRQ: 0x%04x\n", intmask);
610
611exit:
612	mutex_unlock(&host->cmd_mutex);
613	alcor_unmask_sd_irqs(host);
614	return ret;
615}
616
617
618static irqreturn_t alcor_irq(int irq, void *d)
619{
620	struct alcor_sdmmc_host *host = d;
621	struct alcor_pci_priv *priv = host->alcor_pci;
622	u32 status, tmp;
623	irqreturn_t ret;
624	int cmd_done, data_done;
625
626	status = alcor_read32(priv, AU6601_REG_INT_STATUS);
627	if (!status)
628		return IRQ_NONE;
629
630	alcor_write32(priv, status, AU6601_REG_INT_STATUS);
631
632	tmp = status & (AU6601_INT_READ_BUF_RDY | AU6601_INT_WRITE_BUF_RDY
633			| AU6601_INT_DATA_END | AU6601_INT_DMA_END
634			| AU6601_INT_CMD_END);
635	if (tmp == status) {
636		cmd_done = alcor_cmd_irq_done(host, tmp);
637		data_done = alcor_data_irq_done(host, tmp);
638		/* use fast path for simple tasks */
639		if (cmd_done && data_done) {
640			ret = IRQ_HANDLED;
641			goto alcor_irq_done;
642		}
643	}
644
645	host->irq_status_sd = status;
646	ret = IRQ_WAKE_THREAD;
647	alcor_mask_sd_irqs(host);
648alcor_irq_done:
649	return ret;
650}
651
652static void alcor_set_clock(struct alcor_sdmmc_host *host, unsigned int clock)
653{
654	struct alcor_pci_priv *priv = host->alcor_pci;
655	int i, diff = 0x7fffffff, tmp_clock = 0;
656	u16 clk_src = 0;
657	u8 clk_div = 0;
658
659	if (clock == 0) {
660		alcor_write16(priv, 0, AU6601_CLK_SELECT);
661		return;
662	}
663
664	for (i = 0; i < ARRAY_SIZE(alcor_pll_cfg); i++) {
665		unsigned int tmp_div, tmp_diff;
666		const struct alcor_pll_conf *cfg = &alcor_pll_cfg[i];
667
668		tmp_div = DIV_ROUND_UP(cfg->clk_src_freq, clock);
669		if (cfg->min_div > tmp_div || tmp_div > cfg->max_div)
670			continue;
671
672		tmp_clock = DIV_ROUND_UP(cfg->clk_src_freq, tmp_div);
673		tmp_diff = abs(clock - tmp_clock);
674
675		if (tmp_diff < diff) {
676			diff = tmp_diff;
677			clk_src = cfg->clk_src_reg;
678			clk_div = tmp_div;
679		}
680	}
681
682	clk_src |= ((clk_div - 1) << 8);
683	clk_src |= AU6601_CLK_ENABLE;
684
685	dev_dbg(host->dev, "set freq %d cal freq %d, use div %d, mod %x\n",
686			clock, tmp_clock, clk_div, clk_src);
687
688	alcor_write16(priv, clk_src, AU6601_CLK_SELECT);
689
690}
691
692static void alcor_set_timing(struct mmc_host *mmc, struct mmc_ios *ios)
693{
694	struct alcor_sdmmc_host *host = mmc_priv(mmc);
695
696	if (ios->timing == MMC_TIMING_LEGACY) {
697		alcor_rmw8(host, AU6601_CLK_DELAY,
698			    AU6601_CLK_POSITIVE_EDGE_ALL, 0);
699	} else {
700		alcor_rmw8(host, AU6601_CLK_DELAY,
701			    0, AU6601_CLK_POSITIVE_EDGE_ALL);
702	}
703}
704
705static void alcor_set_bus_width(struct mmc_host *mmc, struct mmc_ios *ios)
706{
707	struct alcor_sdmmc_host *host = mmc_priv(mmc);
708	struct alcor_pci_priv *priv = host->alcor_pci;
709
710	if (ios->bus_width == MMC_BUS_WIDTH_1) {
711		alcor_write8(priv, 0, AU6601_REG_BUS_CTRL);
712	} else if (ios->bus_width == MMC_BUS_WIDTH_4) {
713		alcor_write8(priv, AU6601_BUS_WIDTH_4BIT,
714			      AU6601_REG_BUS_CTRL);
715	} else
716		dev_err(host->dev, "Unknown BUS mode\n");
717
718}
719
720static int alcor_card_busy(struct mmc_host *mmc)
721{
722	struct alcor_sdmmc_host *host = mmc_priv(mmc);
723	struct alcor_pci_priv *priv = host->alcor_pci;
724	u8 status;
725
726	/* Check whether dat[0:3] low */
727	status = alcor_read8(priv, AU6601_DATA_PIN_STATE);
728
729	return !(status & AU6601_BUS_STAT_DAT_MASK);
730}
731
732static int alcor_get_cd(struct mmc_host *mmc)
733{
734	struct alcor_sdmmc_host *host = mmc_priv(mmc);
735	struct alcor_pci_priv *priv = host->alcor_pci;
736	u8 detect;
737
738	detect = alcor_read8(priv, AU6601_DETECT_STATUS)
739		& AU6601_DETECT_STATUS_M;
740	/* check if card is present then send command and data */
741	return (detect == AU6601_SD_DETECTED);
742}
743
744static int alcor_get_ro(struct mmc_host *mmc)
745{
746	struct alcor_sdmmc_host *host = mmc_priv(mmc);
747	struct alcor_pci_priv *priv = host->alcor_pci;
748	u8 status;
749
750	/* get write protect pin status */
751	status = alcor_read8(priv, AU6601_INTERFACE_MODE_CTRL);
752
753	return !!(status & AU6601_SD_CARD_WP);
754}
755
756static void alcor_request(struct mmc_host *mmc, struct mmc_request *mrq)
757{
758	struct alcor_sdmmc_host *host = mmc_priv(mmc);
759
760	mutex_lock(&host->cmd_mutex);
761
762	host->mrq = mrq;
763
764	/* check if card is present then send command and data */
765	if (alcor_get_cd(mmc))
766		alcor_send_cmd(host, mrq->cmd, true);
767	else {
768		mrq->cmd->error = -ENOMEDIUM;
769		alcor_request_complete(host, 1);
770	}
771
772	mutex_unlock(&host->cmd_mutex);
773}
774
775static void alcor_pre_req(struct mmc_host *mmc,
776			   struct mmc_request *mrq)
777{
778	struct alcor_sdmmc_host *host = mmc_priv(mmc);
779	struct mmc_data *data = mrq->data;
780	struct mmc_command *cmd = mrq->cmd;
781	struct scatterlist *sg;
782	unsigned int i, sg_len;
783
784	if (!data || !cmd)
785		return;
786
787	data->host_cookie = COOKIE_UNMAPPED;
788
789	/* FIXME: looks like the DMA engine works only with CMD18 */
790	if (cmd->opcode != MMC_READ_MULTIPLE_BLOCK
791			&& cmd->opcode != MMC_WRITE_MULTIPLE_BLOCK)
792		return;
793	/*
794	 * We don't do DMA on "complex" transfers, i.e. with
795	 * non-word-aligned buffers or lengths. A future improvement
796	 * could be made to use temporary DMA bounce-buffers when these
797	 * requirements are not met.
798	 *
799	 * Also, we don't bother with all the DMA setup overhead for
800	 * short transfers.
801	 */
802	if (data->blocks * data->blksz < AU6601_MAX_DMA_BLOCK_SIZE)
803		return;
804
805	if (data->blksz & 3)
806		return;
807
808	for_each_sg(data->sg, sg, data->sg_len, i) {
809		if (sg->length != AU6601_MAX_DMA_BLOCK_SIZE)
810			return;
811		if (sg->offset != 0)
812			return;
813	}
814
815	/* This data might be unmapped at this time */
816
817	sg_len = dma_map_sg(host->dev, data->sg, data->sg_len,
818			    mmc_get_dma_dir(data));
819	if (sg_len)
820		data->host_cookie = COOKIE_MAPPED;
821
822	data->sg_count = sg_len;
823}
824
825static void alcor_post_req(struct mmc_host *mmc,
826			    struct mmc_request *mrq,
827			    int err)
828{
829	struct alcor_sdmmc_host *host = mmc_priv(mmc);
830	struct mmc_data *data = mrq->data;
831
832	if (!data)
833		return;
834
835	if (data->host_cookie == COOKIE_MAPPED) {
836		dma_unmap_sg(host->dev,
837			     data->sg,
838			     data->sg_len,
839			     mmc_get_dma_dir(data));
840	}
841
842	data->host_cookie = COOKIE_UNMAPPED;
843}
844
845static void alcor_set_power_mode(struct mmc_host *mmc, struct mmc_ios *ios)
846{
847	struct alcor_sdmmc_host *host = mmc_priv(mmc);
848	struct alcor_pci_priv *priv = host->alcor_pci;
849
850	switch (ios->power_mode) {
851	case MMC_POWER_OFF:
852		alcor_set_clock(host, ios->clock);
853		/* set all pins to input */
854		alcor_write8(priv, 0, AU6601_OUTPUT_ENABLE);
855		/* turn of VDD */
856		alcor_write8(priv, 0, AU6601_POWER_CONTROL);
857		break;
858	case MMC_POWER_UP:
859		break;
860	case MMC_POWER_ON:
861		/* This is most trickiest part. The order and timings of
862		 * instructions seems to play important role. Any changes may
863		 * confuse internal state engine if this HW.
864		 * FIXME: If we will ever get access to documentation, then this
865		 * part should be reviewed again.
866		 */
867
868		/* enable SD card mode */
869		alcor_write8(priv, AU6601_SD_CARD,
870			      AU6601_ACTIVE_CTRL);
871		/* set signal voltage to 3.3V */
872		alcor_write8(priv, 0, AU6601_OPT);
873		/* no documentation about clk delay, for now just try to mimic
874		 * original driver.
875		 */
876		alcor_write8(priv, 0x20, AU6601_CLK_DELAY);
877		/* set BUS width to 1 bit */
878		alcor_write8(priv, 0, AU6601_REG_BUS_CTRL);
879		/* set CLK first time */
880		alcor_set_clock(host, ios->clock);
881		/* power on VDD */
882		alcor_write8(priv, AU6601_SD_CARD,
883			      AU6601_POWER_CONTROL);
884		/* wait until the CLK will get stable */
885		mdelay(20);
886		/* set CLK again, mimic original driver. */
887		alcor_set_clock(host, ios->clock);
888
889		/* enable output */
890		alcor_write8(priv, AU6601_SD_CARD,
891			      AU6601_OUTPUT_ENABLE);
892		/* The clk will not work on au6621. We need to trigger data
893		 * transfer.
894		 */
895		alcor_write8(priv, AU6601_DATA_WRITE,
896			      AU6601_DATA_XFER_CTRL);
897		/* configure timeout. Not clear what exactly it means. */
898		alcor_write8(priv, 0x7d, AU6601_TIME_OUT_CTRL);
899		mdelay(100);
900		break;
901	default:
902		dev_err(host->dev, "Unknown power parameter\n");
903	}
904}
905
906static void alcor_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
907{
908	struct alcor_sdmmc_host *host = mmc_priv(mmc);
909
910	mutex_lock(&host->cmd_mutex);
911
912	dev_dbg(host->dev, "set ios. bus width: %x, power mode: %x\n",
913		ios->bus_width, ios->power_mode);
914
915	if (ios->power_mode != host->cur_power_mode) {
916		alcor_set_power_mode(mmc, ios);
917		host->cur_power_mode = ios->power_mode;
918	} else {
919		alcor_set_timing(mmc, ios);
920		alcor_set_bus_width(mmc, ios);
921		alcor_set_clock(host, ios->clock);
922	}
923
924	mutex_unlock(&host->cmd_mutex);
925}
926
927static int alcor_signal_voltage_switch(struct mmc_host *mmc,
928				       struct mmc_ios *ios)
929{
930	struct alcor_sdmmc_host *host = mmc_priv(mmc);
931
932	mutex_lock(&host->cmd_mutex);
933
934	switch (ios->signal_voltage) {
935	case MMC_SIGNAL_VOLTAGE_330:
936		alcor_rmw8(host, AU6601_OPT, AU6601_OPT_SD_18V, 0);
937		break;
938	case MMC_SIGNAL_VOLTAGE_180:
939		alcor_rmw8(host, AU6601_OPT, 0, AU6601_OPT_SD_18V);
940		break;
941	default:
942		/* No signal voltage switch required */
943		break;
944	}
945
946	mutex_unlock(&host->cmd_mutex);
947	return 0;
948}
949
950static const struct mmc_host_ops alcor_sdc_ops = {
951	.card_busy	= alcor_card_busy,
952	.get_cd		= alcor_get_cd,
953	.get_ro		= alcor_get_ro,
954	.post_req	= alcor_post_req,
955	.pre_req	= alcor_pre_req,
956	.request	= alcor_request,
957	.set_ios	= alcor_set_ios,
958	.start_signal_voltage_switch = alcor_signal_voltage_switch,
959};
960
961static void alcor_timeout_timer(struct work_struct *work)
962{
963	struct delayed_work *d = to_delayed_work(work);
964	struct alcor_sdmmc_host *host = container_of(d, struct alcor_sdmmc_host,
965						timeout_work);
966	mutex_lock(&host->cmd_mutex);
967
968	dev_dbg(host->dev, "triggered timeout\n");
969	if (host->mrq) {
970		dev_err(host->dev, "Timeout waiting for hardware interrupt.\n");
971
972		if (host->data) {
973			host->data->error = -ETIMEDOUT;
974		} else {
975			if (host->cmd)
976				host->cmd->error = -ETIMEDOUT;
977			else
978				host->mrq->cmd->error = -ETIMEDOUT;
979		}
980
981		alcor_reset(host, AU6601_RESET_CMD | AU6601_RESET_DATA);
982		alcor_request_complete(host, 0);
983	}
984
985	mutex_unlock(&host->cmd_mutex);
986}
987
988static void alcor_hw_init(struct alcor_sdmmc_host *host)
989{
990	struct alcor_pci_priv *priv = host->alcor_pci;
991	struct alcor_dev_cfg *cfg = priv->cfg;
992
993	/* FIXME: This part is a mimics HW init of original driver.
994	 * If we will ever get access to documentation, then this part
995	 * should be reviewed again.
996	 */
997
998	/* reset command state engine */
999	alcor_reset(host, AU6601_RESET_CMD);
1000
1001	alcor_write8(priv, 0, AU6601_DMA_BOUNDARY);
1002	/* enable sd card mode */
1003	alcor_write8(priv, AU6601_SD_CARD, AU6601_ACTIVE_CTRL);
1004
1005	/* set BUS width to 1 bit */
1006	alcor_write8(priv, 0, AU6601_REG_BUS_CTRL);
1007
1008	/* reset data state engine */
1009	alcor_reset(host, AU6601_RESET_DATA);
1010	/* Not sure if a voodoo with AU6601_DMA_BOUNDARY is really needed */
1011	alcor_write8(priv, 0, AU6601_DMA_BOUNDARY);
1012
1013	alcor_write8(priv, 0, AU6601_INTERFACE_MODE_CTRL);
1014	/* not clear what we are doing here. */
1015	alcor_write8(priv, 0x44, AU6601_PAD_DRIVE0);
1016	alcor_write8(priv, 0x44, AU6601_PAD_DRIVE1);
1017	alcor_write8(priv, 0x00, AU6601_PAD_DRIVE2);
1018
1019	/* for 6601 - dma_boundary; for 6621 - dma_page_cnt
1020	 * exact meaning of this register is not clear.
1021	 */
1022	alcor_write8(priv, cfg->dma, AU6601_DMA_BOUNDARY);
1023
1024	/* make sure all pins are set to input and VDD is off */
1025	alcor_write8(priv, 0, AU6601_OUTPUT_ENABLE);
1026	alcor_write8(priv, 0, AU6601_POWER_CONTROL);
1027
1028	alcor_write8(priv, AU6601_DETECT_EN, AU6601_DETECT_STATUS);
1029	/* now we should be safe to enable IRQs */
1030	alcor_unmask_sd_irqs(host);
1031}
1032
1033static void alcor_hw_uninit(struct alcor_sdmmc_host *host)
1034{
1035	struct alcor_pci_priv *priv = host->alcor_pci;
1036
1037	alcor_mask_sd_irqs(host);
1038	alcor_reset(host, AU6601_RESET_CMD | AU6601_RESET_DATA);
1039
1040	alcor_write8(priv, 0, AU6601_DETECT_STATUS);
1041
1042	alcor_write8(priv, 0, AU6601_OUTPUT_ENABLE);
1043	alcor_write8(priv, 0, AU6601_POWER_CONTROL);
1044
1045	alcor_write8(priv, 0, AU6601_OPT);
1046}
1047
1048static void alcor_init_mmc(struct alcor_sdmmc_host *host)
1049{
1050	struct mmc_host *mmc = mmc_from_priv(host);
1051
1052	mmc->f_min = AU6601_MIN_CLOCK;
1053	mmc->f_max = AU6601_MAX_CLOCK;
1054	mmc->ocr_avail = MMC_VDD_33_34;
1055	mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SD_HIGHSPEED
1056		| MMC_CAP_UHS_SDR12 | MMC_CAP_UHS_SDR25 | MMC_CAP_UHS_SDR50
1057		| MMC_CAP_UHS_SDR104 | MMC_CAP_UHS_DDR50;
1058	mmc->caps2 = MMC_CAP2_NO_SDIO;
1059	mmc->ops = &alcor_sdc_ops;
1060
1061	/* The hardware does DMA data transfer of 4096 bytes to/from a single
1062	 * buffer address. Scatterlists are not supported at the hardware
1063	 * level, however we can work with them at the driver level,
1064	 * provided that each segment is exactly 4096 bytes in size.
1065	 * Upon DMA completion of a single segment (signalled via IRQ), we
1066	 * immediately proceed to transfer the next segment from the
1067	 * scatterlist.
1068	 *
1069	 * The overall request is limited to 240 sectors, matching the
1070	 * original vendor driver.
1071	 */
1072	mmc->max_segs = AU6601_MAX_DMA_SEGMENTS;
1073	mmc->max_seg_size = AU6601_MAX_DMA_BLOCK_SIZE;
1074	mmc->max_blk_count = 240;
1075	mmc->max_req_size = mmc->max_blk_count * mmc->max_blk_size;
1076	dma_set_max_seg_size(host->dev, mmc->max_seg_size);
1077}
1078
1079static int alcor_pci_sdmmc_drv_probe(struct platform_device *pdev)
1080{
1081	struct alcor_pci_priv *priv = pdev->dev.platform_data;
1082	struct mmc_host *mmc;
1083	struct alcor_sdmmc_host *host;
1084	int ret;
1085
1086	mmc = mmc_alloc_host(sizeof(*host), &pdev->dev);
1087	if (!mmc) {
1088		dev_err(&pdev->dev, "Can't allocate MMC\n");
1089		return -ENOMEM;
1090	}
1091
1092	host = mmc_priv(mmc);
1093	host->dev = &pdev->dev;
1094	host->cur_power_mode = MMC_POWER_UNDEFINED;
1095	host->alcor_pci = priv;
1096
1097	/* make sure irqs are disabled */
1098	alcor_write32(priv, 0, AU6601_REG_INT_ENABLE);
1099	alcor_write32(priv, 0, AU6601_MS_INT_ENABLE);
1100
1101	ret = devm_request_threaded_irq(&pdev->dev, priv->irq,
1102			alcor_irq, alcor_irq_thread, IRQF_SHARED,
1103			DRV_NAME_ALCOR_PCI_SDMMC, host);
1104
1105	if (ret) {
1106		dev_err(&pdev->dev, "Failed to get irq for data line\n");
1107		goto free_host;
1108	}
1109
1110	mutex_init(&host->cmd_mutex);
1111	INIT_DELAYED_WORK(&host->timeout_work, alcor_timeout_timer);
1112
1113	alcor_init_mmc(host);
1114	alcor_hw_init(host);
1115
1116	dev_set_drvdata(&pdev->dev, host);
1117	ret = mmc_add_host(mmc);
1118	if (ret)
1119		goto free_host;
1120
1121	return 0;
1122
1123free_host:
1124	mmc_free_host(mmc);
1125	return ret;
1126}
1127
1128static void alcor_pci_sdmmc_drv_remove(struct platform_device *pdev)
1129{
1130	struct alcor_sdmmc_host *host = dev_get_drvdata(&pdev->dev);
1131	struct mmc_host *mmc = mmc_from_priv(host);
1132
1133	if (cancel_delayed_work_sync(&host->timeout_work))
1134		alcor_request_complete(host, 0);
1135
1136	alcor_hw_uninit(host);
1137	mmc_remove_host(mmc);
1138	mmc_free_host(mmc);
1139}
1140
1141#ifdef CONFIG_PM_SLEEP
1142static int alcor_pci_sdmmc_suspend(struct device *dev)
1143{
1144	struct alcor_sdmmc_host *host = dev_get_drvdata(dev);
1145
1146	if (cancel_delayed_work_sync(&host->timeout_work))
1147		alcor_request_complete(host, 0);
1148
1149	alcor_hw_uninit(host);
1150
1151	return 0;
1152}
1153
1154static int alcor_pci_sdmmc_resume(struct device *dev)
1155{
1156	struct alcor_sdmmc_host *host = dev_get_drvdata(dev);
1157
1158	alcor_hw_init(host);
1159
1160	return 0;
1161}
1162#endif /* CONFIG_PM_SLEEP */
1163
1164static SIMPLE_DEV_PM_OPS(alcor_mmc_pm_ops, alcor_pci_sdmmc_suspend,
1165			 alcor_pci_sdmmc_resume);
1166
1167static const struct platform_device_id alcor_pci_sdmmc_ids[] = {
1168	{
1169		.name = DRV_NAME_ALCOR_PCI_SDMMC,
1170	}, {
1171		/* sentinel */
1172	}
1173};
1174MODULE_DEVICE_TABLE(platform, alcor_pci_sdmmc_ids);
1175
1176static struct platform_driver alcor_pci_sdmmc_driver = {
1177	.probe		= alcor_pci_sdmmc_drv_probe,
1178	.remove_new	= alcor_pci_sdmmc_drv_remove,
1179	.id_table	= alcor_pci_sdmmc_ids,
1180	.driver		= {
1181		.name	= DRV_NAME_ALCOR_PCI_SDMMC,
1182		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1183		.pm	= &alcor_mmc_pm_ops
1184	},
1185};
1186module_platform_driver(alcor_pci_sdmmc_driver);
1187
1188MODULE_AUTHOR("Oleksij Rempel <linux@rempel-privat.de>");
1189MODULE_DESCRIPTION("PCI driver for Alcor Micro AU6601 Secure Digital Host Controller Interface");
1190MODULE_LICENSE("GPL");
1191