1 /*
2  * Freescale eSDHC controller driver.
3  *
4  * Copyright (c) 2007, 2010, 2012 Freescale Semiconductor, Inc.
5  * Copyright (c) 2009 MontaVista Software, Inc.
6  *
7  * Authors: Xiaobo Xie <X.Xie@freescale.com>
8  *	    Anton Vorontsov <avorontsov@ru.mvista.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or (at
13  * your option) any later version.
14  */
15 
16 #include <linux/err.h>
17 #include <linux/io.h>
18 #include <linux/of.h>
19 #include <linux/delay.h>
20 #include <linux/module.h>
21 #include <linux/mmc/host.h>
22 #include "sdhci-pltfm.h"
23 #include "sdhci-esdhc.h"
24 
25 #define VENDOR_V_22	0x12
26 #define VENDOR_V_23	0x13
27 static u32 esdhc_readl(struct sdhci_host *host, int reg)
28 {
29 	u32 ret;
30 
31 	ret = in_be32(host->ioaddr + reg);
32 	/*
33 	 * The bit of ADMA flag in eSDHC is not compatible with standard
34 	 * SDHC register, so set fake flag SDHCI_CAN_DO_ADMA2 when ADMA is
35 	 * supported by eSDHC.
36 	 * And for many FSL eSDHC controller, the reset value of field
37 	 * SDHCI_CAN_DO_ADMA1 is one, but some of them can't support ADMA,
38 	 * only these vendor version is greater than 2.2/0x12 support ADMA.
39 	 * For FSL eSDHC, must aligned 4-byte, so use 0xFC to read the
40 	 * the verdor version number, oxFE is SDHCI_HOST_VERSION.
41 	 */
42 	if ((reg == SDHCI_CAPABILITIES) && (ret & SDHCI_CAN_DO_ADMA1)) {
43 		u32 tmp = in_be32(host->ioaddr + SDHCI_SLOT_INT_STATUS);
44 		tmp = (tmp & SDHCI_VENDOR_VER_MASK) >> SDHCI_VENDOR_VER_SHIFT;
45 		if (tmp > VENDOR_V_22)
46 			ret |= SDHCI_CAN_DO_ADMA2;
47 	}
48 
49 	return ret;
50 }
51 
52 static u16 esdhc_readw(struct sdhci_host *host, int reg)
53 {
54 	u16 ret;
55 	int base = reg & ~0x3;
56 	int shift = (reg & 0x2) * 8;
57 
58 	if (unlikely(reg == SDHCI_HOST_VERSION))
59 		ret = in_be32(host->ioaddr + base) & 0xffff;
60 	else
61 		ret = (in_be32(host->ioaddr + base) >> shift) & 0xffff;
62 	return ret;
63 }
64 
65 static u8 esdhc_readb(struct sdhci_host *host, int reg)
66 {
67 	int base = reg & ~0x3;
68 	int shift = (reg & 0x3) * 8;
69 	u8 ret = (in_be32(host->ioaddr + base) >> shift) & 0xff;
70 
71 	/*
72 	 * "DMA select" locates at offset 0x28 in SD specification, but on
73 	 * P5020 or P3041, it locates at 0x29.
74 	 */
75 	if (reg == SDHCI_HOST_CONTROL) {
76 		u32 dma_bits;
77 
78 		dma_bits = in_be32(host->ioaddr + reg);
79 		/* DMA select is 22,23 bits in Protocol Control Register */
80 		dma_bits = (dma_bits >> 5) & SDHCI_CTRL_DMA_MASK;
81 
82 		/* fixup the result */
83 		ret &= ~SDHCI_CTRL_DMA_MASK;
84 		ret |= dma_bits;
85 	}
86 
87 	return ret;
88 }
89 
90 static void esdhc_writel(struct sdhci_host *host, u32 val, int reg)
91 {
92 	/*
93 	 * Enable IRQSTATEN[BGESEN] is just to set IRQSTAT[BGE]
94 	 * when SYSCTL[RSTD]) is set for some special operations.
95 	 * No any impact other operation.
96 	 */
97 	if (reg == SDHCI_INT_ENABLE)
98 		val |= SDHCI_INT_BLK_GAP;
99 	sdhci_be32bs_writel(host, val, reg);
100 }
101 
102 static void esdhc_writew(struct sdhci_host *host, u16 val, int reg)
103 {
104 	if (reg == SDHCI_BLOCK_SIZE) {
105 		/*
106 		 * Two last DMA bits are reserved, and first one is used for
107 		 * non-standard blksz of 4096 bytes that we don't support
108 		 * yet. So clear the DMA boundary bits.
109 		 */
110 		val &= ~SDHCI_MAKE_BLKSZ(0x7, 0);
111 	}
112 	sdhci_be32bs_writew(host, val, reg);
113 }
114 
115 static void esdhc_writeb(struct sdhci_host *host, u8 val, int reg)
116 {
117 	/*
118 	 * "DMA select" location is offset 0x28 in SD specification, but on
119 	 * P5020 or P3041, it's located at 0x29.
120 	 */
121 	if (reg == SDHCI_HOST_CONTROL) {
122 		u32 dma_bits;
123 
124 		/*
125 		 * If host control register is not standard, exit
126 		 * this function
127 		 */
128 		if (host->quirks2 & SDHCI_QUIRK2_BROKEN_HOST_CONTROL)
129 			return;
130 
131 		/* DMA select is 22,23 bits in Protocol Control Register */
132 		dma_bits = (val & SDHCI_CTRL_DMA_MASK) << 5;
133 		clrsetbits_be32(host->ioaddr + reg , SDHCI_CTRL_DMA_MASK << 5,
134 			dma_bits);
135 		val &= ~SDHCI_CTRL_DMA_MASK;
136 		val |= in_be32(host->ioaddr + reg) & SDHCI_CTRL_DMA_MASK;
137 	}
138 
139 	/* Prevent SDHCI core from writing reserved bits (e.g. HISPD). */
140 	if (reg == SDHCI_HOST_CONTROL)
141 		val &= ~ESDHC_HOST_CONTROL_RES;
142 	sdhci_be32bs_writeb(host, val, reg);
143 }
144 
145 /*
146  * For Abort or Suspend after Stop at Block Gap, ignore the ADMA
147  * error(IRQSTAT[ADMAE]) if both Transfer Complete(IRQSTAT[TC])
148  * and Block Gap Event(IRQSTAT[BGE]) are also set.
149  * For Continue, apply soft reset for data(SYSCTL[RSTD]);
150  * and re-issue the entire read transaction from beginning.
151  */
152 static void esdhci_of_adma_workaround(struct sdhci_host *host, u32 intmask)
153 {
154 	u32 tmp;
155 	bool applicable;
156 	dma_addr_t dmastart;
157 	dma_addr_t dmanow;
158 
159 	tmp = in_be32(host->ioaddr + SDHCI_SLOT_INT_STATUS);
160 	tmp = (tmp & SDHCI_VENDOR_VER_MASK) >> SDHCI_VENDOR_VER_SHIFT;
161 
162 	applicable = (intmask & SDHCI_INT_DATA_END) &&
163 		(intmask & SDHCI_INT_BLK_GAP) &&
164 		(tmp == VENDOR_V_23);
165 	if (!applicable)
166 		return;
167 
168 	host->data->error = 0;
169 	dmastart = sg_dma_address(host->data->sg);
170 	dmanow = dmastart + host->data->bytes_xfered;
171 	/*
172 	 * Force update to the next DMA block boundary.
173 	 */
174 	dmanow = (dmanow & ~(SDHCI_DEFAULT_BOUNDARY_SIZE - 1)) +
175 		SDHCI_DEFAULT_BOUNDARY_SIZE;
176 	host->data->bytes_xfered = dmanow - dmastart;
177 	sdhci_writel(host, dmanow, SDHCI_DMA_ADDRESS);
178 }
179 
180 static int esdhc_of_enable_dma(struct sdhci_host *host)
181 {
182 	setbits32(host->ioaddr + ESDHC_DMA_SYSCTL, ESDHC_DMA_SNOOP);
183 	return 0;
184 }
185 
186 static unsigned int esdhc_of_get_max_clock(struct sdhci_host *host)
187 {
188 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
189 
190 	return pltfm_host->clock;
191 }
192 
193 static unsigned int esdhc_of_get_min_clock(struct sdhci_host *host)
194 {
195 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
196 
197 	return pltfm_host->clock / 256 / 16;
198 }
199 
200 static void esdhc_of_set_clock(struct sdhci_host *host, unsigned int clock)
201 {
202 
203 	int pre_div = 2;
204 	int div = 1;
205 	u32 temp;
206 
207 	if (clock == 0)
208 		goto out;
209 
210 	/* Workaround to reduce the clock frequency for p1010 esdhc */
211 	if (of_find_compatible_node(NULL, NULL, "fsl,p1010-esdhc")) {
212 		if (clock > 20000000)
213 			clock -= 5000000;
214 		if (clock > 40000000)
215 			clock -= 5000000;
216 	}
217 
218 	temp = sdhci_readl(host, ESDHC_SYSTEM_CONTROL);
219 	temp &= ~(ESDHC_CLOCK_IPGEN | ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN
220 		| ESDHC_CLOCK_MASK);
221 	sdhci_writel(host, temp, ESDHC_SYSTEM_CONTROL);
222 
223 	while (host->max_clk / pre_div / 16 > clock && pre_div < 256)
224 		pre_div *= 2;
225 
226 	while (host->max_clk / pre_div / div > clock && div < 16)
227 		div++;
228 
229 	dev_dbg(mmc_dev(host->mmc), "desired SD clock: %d, actual: %d\n",
230 		clock, host->max_clk / pre_div / div);
231 
232 	pre_div >>= 1;
233 	div--;
234 
235 	temp = sdhci_readl(host, ESDHC_SYSTEM_CONTROL);
236 	temp |= (ESDHC_CLOCK_IPGEN | ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN
237 		| (div << ESDHC_DIVIDER_SHIFT)
238 		| (pre_div << ESDHC_PREDIV_SHIFT));
239 	sdhci_writel(host, temp, ESDHC_SYSTEM_CONTROL);
240 	mdelay(1);
241 out:
242 	host->clock = clock;
243 }
244 
245 #ifdef CONFIG_PM
246 static u32 esdhc_proctl;
247 static void esdhc_of_suspend(struct sdhci_host *host)
248 {
249 	esdhc_proctl = sdhci_be32bs_readl(host, SDHCI_HOST_CONTROL);
250 }
251 
252 static void esdhc_of_resume(struct sdhci_host *host)
253 {
254 	esdhc_of_enable_dma(host);
255 	sdhci_be32bs_writel(host, esdhc_proctl, SDHCI_HOST_CONTROL);
256 }
257 #endif
258 
259 static void esdhc_of_platform_init(struct sdhci_host *host)
260 {
261 	u32 vvn;
262 
263 	vvn = in_be32(host->ioaddr + SDHCI_SLOT_INT_STATUS);
264 	vvn = (vvn & SDHCI_VENDOR_VER_MASK) >> SDHCI_VENDOR_VER_SHIFT;
265 	if (vvn == VENDOR_V_22)
266 		host->quirks2 |= SDHCI_QUIRK2_HOST_NO_CMD23;
267 
268 	if (vvn > VENDOR_V_22)
269 		host->quirks &= ~SDHCI_QUIRK_NO_BUSY_IRQ;
270 }
271 
272 static int esdhc_pltfm_bus_width(struct sdhci_host *host, int width)
273 {
274 	u32 ctrl;
275 
276 	switch (width) {
277 	case MMC_BUS_WIDTH_8:
278 		ctrl = ESDHC_CTRL_8BITBUS;
279 		break;
280 
281 	case MMC_BUS_WIDTH_4:
282 		ctrl = ESDHC_CTRL_4BITBUS;
283 		break;
284 
285 	default:
286 		ctrl = 0;
287 		break;
288 	}
289 
290 	clrsetbits_be32(host->ioaddr + SDHCI_HOST_CONTROL,
291 			ESDHC_CTRL_BUSWIDTH_MASK, ctrl);
292 
293 	return 0;
294 }
295 
296 static const struct sdhci_ops sdhci_esdhc_ops = {
297 	.read_l = esdhc_readl,
298 	.read_w = esdhc_readw,
299 	.read_b = esdhc_readb,
300 	.write_l = esdhc_writel,
301 	.write_w = esdhc_writew,
302 	.write_b = esdhc_writeb,
303 	.set_clock = esdhc_of_set_clock,
304 	.enable_dma = esdhc_of_enable_dma,
305 	.get_max_clock = esdhc_of_get_max_clock,
306 	.get_min_clock = esdhc_of_get_min_clock,
307 	.platform_init = esdhc_of_platform_init,
308 #ifdef CONFIG_PM
309 	.platform_suspend = esdhc_of_suspend,
310 	.platform_resume = esdhc_of_resume,
311 #endif
312 	.adma_workaround = esdhci_of_adma_workaround,
313 	.platform_bus_width = esdhc_pltfm_bus_width,
314 };
315 
316 static const struct sdhci_pltfm_data sdhci_esdhc_pdata = {
317 	/*
318 	 * card detection could be handled via GPIO
319 	 * eSDHC cannot support End Attribute in NOP ADMA descriptor
320 	 */
321 	.quirks = ESDHC_DEFAULT_QUIRKS | SDHCI_QUIRK_BROKEN_CARD_DETECTION
322 		| SDHCI_QUIRK_NO_CARD_NO_RESET
323 		| SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC,
324 	.ops = &sdhci_esdhc_ops,
325 };
326 
327 static int sdhci_esdhc_probe(struct platform_device *pdev)
328 {
329 	struct sdhci_host *host;
330 	struct device_node *np;
331 	int ret;
332 
333 	host = sdhci_pltfm_init(pdev, &sdhci_esdhc_pdata, 0);
334 	if (IS_ERR(host))
335 		return PTR_ERR(host);
336 
337 	sdhci_get_of_property(pdev);
338 
339 	np = pdev->dev.of_node;
340 	if (of_device_is_compatible(np, "fsl,p2020-esdhc")) {
341 		/*
342 		 * Freescale messed up with P2020 as it has a non-standard
343 		 * host control register
344 		 */
345 		host->quirks2 |= SDHCI_QUIRK2_BROKEN_HOST_CONTROL;
346 	}
347 
348 	/* call to generic mmc_of_parse to support additional capabilities */
349 	mmc_of_parse(host->mmc);
350 	mmc_of_parse_voltage(np, &host->ocr_mask);
351 
352 	ret = sdhci_add_host(host);
353 	if (ret)
354 		sdhci_pltfm_free(pdev);
355 
356 	return ret;
357 }
358 
359 static int sdhci_esdhc_remove(struct platform_device *pdev)
360 {
361 	return sdhci_pltfm_unregister(pdev);
362 }
363 
364 static const struct of_device_id sdhci_esdhc_of_match[] = {
365 	{ .compatible = "fsl,mpc8379-esdhc" },
366 	{ .compatible = "fsl,mpc8536-esdhc" },
367 	{ .compatible = "fsl,esdhc" },
368 	{ }
369 };
370 MODULE_DEVICE_TABLE(of, sdhci_esdhc_of_match);
371 
372 static struct platform_driver sdhci_esdhc_driver = {
373 	.driver = {
374 		.name = "sdhci-esdhc",
375 		.owner = THIS_MODULE,
376 		.of_match_table = sdhci_esdhc_of_match,
377 		.pm = SDHCI_PLTFM_PMOPS,
378 	},
379 	.probe = sdhci_esdhc_probe,
380 	.remove = sdhci_esdhc_remove,
381 };
382 
383 module_platform_driver(sdhci_esdhc_driver);
384 
385 MODULE_DESCRIPTION("SDHCI OF driver for Freescale MPC eSDHC");
386 MODULE_AUTHOR("Xiaobo Xie <X.Xie@freescale.com>, "
387 	      "Anton Vorontsov <avorontsov@ru.mvista.com>");
388 MODULE_LICENSE("GPL v2");
389