1/*
2 * linux/arch/arm/mach-omap2/gpmc-onenand.c
3 *
4 * Copyright (C) 2006 - 2009 Nokia Corporation
5 * Contacts:	Juha Yrjola
6 *		Tony Lindgren
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <linux/string.h>
14#include <linux/kernel.h>
15#include <linux/platform_device.h>
16#include <linux/mtd/onenand_regs.h>
17#include <linux/io.h>
18#include <linux/omap-gpmc.h>
19#include <linux/platform_data/mtd-onenand-omap2.h>
20#include <linux/err.h>
21
22#include <asm/mach/flash.h>
23
24#include "soc.h"
25
26#define	ONENAND_IO_SIZE	SZ_128K
27
28#define	ONENAND_FLAG_SYNCREAD	(1 << 0)
29#define	ONENAND_FLAG_SYNCWRITE	(1 << 1)
30#define	ONENAND_FLAG_HF		(1 << 2)
31#define	ONENAND_FLAG_VHF	(1 << 3)
32
33static unsigned onenand_flags;
34static unsigned latency;
35
36static struct omap_onenand_platform_data *gpmc_onenand_data;
37
38static struct resource gpmc_onenand_resource = {
39	.flags		= IORESOURCE_MEM,
40};
41
42static struct platform_device gpmc_onenand_device = {
43	.name		= "omap2-onenand",
44	.id		= -1,
45	.num_resources	= 1,
46	.resource	= &gpmc_onenand_resource,
47};
48
49static struct gpmc_settings onenand_async = {
50	.device_width	= GPMC_DEVWIDTH_16BIT,
51	.mux_add_data	= GPMC_MUX_AD,
52};
53
54static struct gpmc_settings onenand_sync = {
55	.burst_read	= true,
56	.burst_wrap	= true,
57	.burst_len	= GPMC_BURST_16,
58	.device_width	= GPMC_DEVWIDTH_16BIT,
59	.mux_add_data	= GPMC_MUX_AD,
60	.wait_pin	= 0,
61};
62
63static void omap2_onenand_calc_async_timings(struct gpmc_timings *t)
64{
65	struct gpmc_device_timings dev_t;
66	const int t_cer = 15;
67	const int t_avdp = 12;
68	const int t_aavdh = 7;
69	const int t_ce = 76;
70	const int t_aa = 76;
71	const int t_oe = 20;
72	const int t_cez = 20; /* max of t_cez, t_oez */
73	const int t_wpl = 40;
74	const int t_wph = 30;
75
76	memset(&dev_t, 0, sizeof(dev_t));
77
78	dev_t.t_avdp_r = max_t(int, t_avdp, t_cer) * 1000;
79	dev_t.t_avdp_w = dev_t.t_avdp_r;
80	dev_t.t_aavdh = t_aavdh * 1000;
81	dev_t.t_aa = t_aa * 1000;
82	dev_t.t_ce = t_ce * 1000;
83	dev_t.t_oe = t_oe * 1000;
84	dev_t.t_cez_r = t_cez * 1000;
85	dev_t.t_cez_w = dev_t.t_cez_r;
86	dev_t.t_wpl = t_wpl * 1000;
87	dev_t.t_wph = t_wph * 1000;
88
89	gpmc_calc_timings(t, &onenand_async, &dev_t);
90}
91
92static void omap2_onenand_set_async_mode(void __iomem *onenand_base)
93{
94	u32 reg;
95
96	/* Ensure sync read and sync write are disabled */
97	reg = readw(onenand_base + ONENAND_REG_SYS_CFG1);
98	reg &= ~ONENAND_SYS_CFG1_SYNC_READ & ~ONENAND_SYS_CFG1_SYNC_WRITE;
99	writew(reg, onenand_base + ONENAND_REG_SYS_CFG1);
100}
101
102static void set_onenand_cfg(void __iomem *onenand_base)
103{
104	u32 reg;
105
106	reg = readw(onenand_base + ONENAND_REG_SYS_CFG1);
107	reg &= ~((0x7 << ONENAND_SYS_CFG1_BRL_SHIFT) | (0x7 << 9));
108	reg |=	(latency << ONENAND_SYS_CFG1_BRL_SHIFT) |
109		ONENAND_SYS_CFG1_BL_16;
110	if (onenand_flags & ONENAND_FLAG_SYNCREAD)
111		reg |= ONENAND_SYS_CFG1_SYNC_READ;
112	else
113		reg &= ~ONENAND_SYS_CFG1_SYNC_READ;
114	if (onenand_flags & ONENAND_FLAG_SYNCWRITE)
115		reg |= ONENAND_SYS_CFG1_SYNC_WRITE;
116	else
117		reg &= ~ONENAND_SYS_CFG1_SYNC_WRITE;
118	if (onenand_flags & ONENAND_FLAG_HF)
119		reg |= ONENAND_SYS_CFG1_HF;
120	else
121		reg &= ~ONENAND_SYS_CFG1_HF;
122	if (onenand_flags & ONENAND_FLAG_VHF)
123		reg |= ONENAND_SYS_CFG1_VHF;
124	else
125		reg &= ~ONENAND_SYS_CFG1_VHF;
126	writew(reg, onenand_base + ONENAND_REG_SYS_CFG1);
127}
128
129static int omap2_onenand_get_freq(struct omap_onenand_platform_data *cfg,
130				  void __iomem *onenand_base)
131{
132	u16 ver = readw(onenand_base + ONENAND_REG_VERSION_ID);
133	int freq;
134
135	switch ((ver >> 4) & 0xf) {
136	case 0:
137		freq = 40;
138		break;
139	case 1:
140		freq = 54;
141		break;
142	case 2:
143		freq = 66;
144		break;
145	case 3:
146		freq = 83;
147		break;
148	case 4:
149		freq = 104;
150		break;
151	default:
152		freq = 54;
153		break;
154	}
155
156	return freq;
157}
158
159static void omap2_onenand_calc_sync_timings(struct gpmc_timings *t,
160					    unsigned int flags,
161					    int freq)
162{
163	struct gpmc_device_timings dev_t;
164	const int t_cer  = 15;
165	const int t_avdp = 12;
166	const int t_cez  = 20; /* max of t_cez, t_oez */
167	const int t_wpl  = 40;
168	const int t_wph  = 30;
169	int min_gpmc_clk_period, t_ces, t_avds, t_avdh, t_ach, t_aavdh, t_rdyo;
170	int div, gpmc_clk_ns;
171
172	if (flags & ONENAND_SYNC_READ)
173		onenand_flags = ONENAND_FLAG_SYNCREAD;
174	else if (flags & ONENAND_SYNC_READWRITE)
175		onenand_flags = ONENAND_FLAG_SYNCREAD | ONENAND_FLAG_SYNCWRITE;
176
177	switch (freq) {
178	case 104:
179		min_gpmc_clk_period = 9600; /* 104 MHz */
180		t_ces   = 3;
181		t_avds  = 4;
182		t_avdh  = 2;
183		t_ach   = 3;
184		t_aavdh = 6;
185		t_rdyo  = 6;
186		break;
187	case 83:
188		min_gpmc_clk_period = 12000; /* 83 MHz */
189		t_ces   = 5;
190		t_avds  = 4;
191		t_avdh  = 2;
192		t_ach   = 6;
193		t_aavdh = 6;
194		t_rdyo  = 9;
195		break;
196	case 66:
197		min_gpmc_clk_period = 15000; /* 66 MHz */
198		t_ces   = 6;
199		t_avds  = 5;
200		t_avdh  = 2;
201		t_ach   = 6;
202		t_aavdh = 6;
203		t_rdyo  = 11;
204		break;
205	default:
206		min_gpmc_clk_period = 18500; /* 54 MHz */
207		t_ces   = 7;
208		t_avds  = 7;
209		t_avdh  = 7;
210		t_ach   = 9;
211		t_aavdh = 7;
212		t_rdyo  = 15;
213		onenand_flags &= ~ONENAND_FLAG_SYNCWRITE;
214		break;
215	}
216
217	div = gpmc_calc_divider(min_gpmc_clk_period);
218	gpmc_clk_ns = gpmc_ticks_to_ns(div);
219	if (gpmc_clk_ns < 15) /* >66Mhz */
220		onenand_flags |= ONENAND_FLAG_HF;
221	else
222		onenand_flags &= ~ONENAND_FLAG_HF;
223	if (gpmc_clk_ns < 12) /* >83Mhz */
224		onenand_flags |= ONENAND_FLAG_VHF;
225	else
226		onenand_flags &= ~ONENAND_FLAG_VHF;
227	if (onenand_flags & ONENAND_FLAG_VHF)
228		latency = 8;
229	else if (onenand_flags & ONENAND_FLAG_HF)
230		latency = 6;
231	else if (gpmc_clk_ns >= 25) /* 40 MHz*/
232		latency = 3;
233	else
234		latency = 4;
235
236	/* Set synchronous read timings */
237	memset(&dev_t, 0, sizeof(dev_t));
238
239	if (onenand_flags & ONENAND_FLAG_SYNCREAD)
240		onenand_sync.sync_read = true;
241	if (onenand_flags & ONENAND_FLAG_SYNCWRITE) {
242		onenand_sync.sync_write = true;
243		onenand_sync.burst_write = true;
244	} else {
245		dev_t.t_avdp_w = max(t_avdp, t_cer) * 1000;
246		dev_t.t_wpl = t_wpl * 1000;
247		dev_t.t_wph = t_wph * 1000;
248		dev_t.t_aavdh = t_aavdh * 1000;
249	}
250	dev_t.ce_xdelay = true;
251	dev_t.avd_xdelay = true;
252	dev_t.oe_xdelay = true;
253	dev_t.we_xdelay = true;
254	dev_t.clk = min_gpmc_clk_period;
255	dev_t.t_bacc = dev_t.clk;
256	dev_t.t_ces = t_ces * 1000;
257	dev_t.t_avds = t_avds * 1000;
258	dev_t.t_avdh = t_avdh * 1000;
259	dev_t.t_ach = t_ach * 1000;
260	dev_t.cyc_iaa = (latency + 1);
261	dev_t.t_cez_r = t_cez * 1000;
262	dev_t.t_cez_w = dev_t.t_cez_r;
263	dev_t.cyc_aavdh_oe = 1;
264	dev_t.t_rdyo = t_rdyo * 1000 + min_gpmc_clk_period;
265
266	gpmc_calc_timings(t, &onenand_sync, &dev_t);
267}
268
269static int omap2_onenand_setup_async(void __iomem *onenand_base)
270{
271	struct gpmc_timings t;
272	int ret;
273
274	if (gpmc_onenand_data->of_node) {
275		gpmc_read_settings_dt(gpmc_onenand_data->of_node,
276				      &onenand_async);
277		if (onenand_async.sync_read || onenand_async.sync_write) {
278			if (onenand_async.sync_write)
279				gpmc_onenand_data->flags |=
280					ONENAND_SYNC_READWRITE;
281			else
282				gpmc_onenand_data->flags |= ONENAND_SYNC_READ;
283			onenand_async.sync_read = false;
284			onenand_async.sync_write = false;
285		}
286	}
287
288	omap2_onenand_set_async_mode(onenand_base);
289
290	omap2_onenand_calc_async_timings(&t);
291
292	ret = gpmc_cs_program_settings(gpmc_onenand_data->cs, &onenand_async);
293	if (ret < 0)
294		return ret;
295
296	ret = gpmc_cs_set_timings(gpmc_onenand_data->cs, &t, &onenand_async);
297	if (ret < 0)
298		return ret;
299
300	omap2_onenand_set_async_mode(onenand_base);
301
302	return 0;
303}
304
305static int omap2_onenand_setup_sync(void __iomem *onenand_base, int *freq_ptr)
306{
307	int ret, freq = *freq_ptr;
308	struct gpmc_timings t;
309
310	if (!freq) {
311		/* Very first call freq is not known */
312		freq = omap2_onenand_get_freq(gpmc_onenand_data, onenand_base);
313		set_onenand_cfg(onenand_base);
314	}
315
316	if (gpmc_onenand_data->of_node) {
317		gpmc_read_settings_dt(gpmc_onenand_data->of_node,
318				      &onenand_sync);
319	} else {
320		/*
321		 * FIXME: Appears to be legacy code from initial ONENAND commit.
322		 * Unclear what boards this is for and if this can be removed.
323		 */
324		if (!cpu_is_omap34xx())
325			onenand_sync.wait_on_read = true;
326	}
327
328	omap2_onenand_calc_sync_timings(&t, gpmc_onenand_data->flags, freq);
329
330	ret = gpmc_cs_program_settings(gpmc_onenand_data->cs, &onenand_sync);
331	if (ret < 0)
332		return ret;
333
334	ret = gpmc_cs_set_timings(gpmc_onenand_data->cs, &t, &onenand_sync);
335	if (ret < 0)
336		return ret;
337
338	set_onenand_cfg(onenand_base);
339
340	*freq_ptr = freq;
341
342	return 0;
343}
344
345static int gpmc_onenand_setup(void __iomem *onenand_base, int *freq_ptr)
346{
347	struct device *dev = &gpmc_onenand_device.dev;
348	unsigned l = ONENAND_SYNC_READ | ONENAND_SYNC_READWRITE;
349	int ret;
350
351	ret = omap2_onenand_setup_async(onenand_base);
352	if (ret) {
353		dev_err(dev, "unable to set to async mode\n");
354		return ret;
355	}
356
357	if (!(gpmc_onenand_data->flags & l))
358		return 0;
359
360	ret = omap2_onenand_setup_sync(onenand_base, freq_ptr);
361	if (ret)
362		dev_err(dev, "unable to set to sync mode\n");
363	return ret;
364}
365
366void gpmc_onenand_init(struct omap_onenand_platform_data *_onenand_data)
367{
368	int err;
369	struct device *dev = &gpmc_onenand_device.dev;
370
371	gpmc_onenand_data = _onenand_data;
372	gpmc_onenand_data->onenand_setup = gpmc_onenand_setup;
373	gpmc_onenand_device.dev.platform_data = gpmc_onenand_data;
374
375	if (cpu_is_omap24xx() &&
376			(gpmc_onenand_data->flags & ONENAND_SYNC_READWRITE)) {
377		dev_warn(dev, "OneNAND using only SYNC_READ on 24xx\n");
378		gpmc_onenand_data->flags &= ~ONENAND_SYNC_READWRITE;
379		gpmc_onenand_data->flags |= ONENAND_SYNC_READ;
380	}
381
382	if (cpu_is_omap34xx())
383		gpmc_onenand_data->flags |= ONENAND_IN_OMAP34XX;
384	else
385		gpmc_onenand_data->flags &= ~ONENAND_IN_OMAP34XX;
386
387	err = gpmc_cs_request(gpmc_onenand_data->cs, ONENAND_IO_SIZE,
388				(unsigned long *)&gpmc_onenand_resource.start);
389	if (err < 0) {
390		dev_err(dev, "Cannot request GPMC CS %d, error %d\n",
391			gpmc_onenand_data->cs, err);
392		return;
393	}
394
395	gpmc_onenand_resource.end = gpmc_onenand_resource.start +
396							ONENAND_IO_SIZE - 1;
397
398	if (platform_device_register(&gpmc_onenand_device) < 0) {
399		dev_err(dev, "Unable to register OneNAND device\n");
400		gpmc_cs_free(gpmc_onenand_data->cs);
401		return;
402	}
403}
404