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 	/* Workaround to reduce the clock frequency for p1010 esdhc */
203 	if (of_find_compatible_node(NULL, NULL, "fsl,p1010-esdhc")) {
204 		if (clock > 20000000)
205 			clock -= 5000000;
206 		if (clock > 40000000)
207 			clock -= 5000000;
208 	}
209 
210 	/* Set the clock */
211 	esdhc_set_clock(host, clock, host->max_clk);
212 }
213 
214 #ifdef CONFIG_PM
215 static u32 esdhc_proctl;
216 static void esdhc_of_suspend(struct sdhci_host *host)
217 {
218 	esdhc_proctl = sdhci_be32bs_readl(host, SDHCI_HOST_CONTROL);
219 }
220 
221 static void esdhc_of_resume(struct sdhci_host *host)
222 {
223 	esdhc_of_enable_dma(host);
224 	sdhci_be32bs_writel(host, esdhc_proctl, SDHCI_HOST_CONTROL);
225 }
226 #endif
227 
228 static void esdhc_of_platform_init(struct sdhci_host *host)
229 {
230 	u32 vvn;
231 
232 	vvn = in_be32(host->ioaddr + SDHCI_SLOT_INT_STATUS);
233 	vvn = (vvn & SDHCI_VENDOR_VER_MASK) >> SDHCI_VENDOR_VER_SHIFT;
234 	if (vvn == VENDOR_V_22)
235 		host->quirks2 |= SDHCI_QUIRK2_HOST_NO_CMD23;
236 
237 	if (vvn > VENDOR_V_22)
238 		host->quirks &= ~SDHCI_QUIRK_NO_BUSY_IRQ;
239 }
240 
241 static int esdhc_pltfm_bus_width(struct sdhci_host *host, int width)
242 {
243 	u32 ctrl;
244 
245 	switch (width) {
246 	case MMC_BUS_WIDTH_8:
247 		ctrl = ESDHC_CTRL_8BITBUS;
248 		break;
249 
250 	case MMC_BUS_WIDTH_4:
251 		ctrl = ESDHC_CTRL_4BITBUS;
252 		break;
253 
254 	default:
255 		ctrl = 0;
256 		break;
257 	}
258 
259 	clrsetbits_be32(host->ioaddr + SDHCI_HOST_CONTROL,
260 			ESDHC_CTRL_BUSWIDTH_MASK, ctrl);
261 
262 	return 0;
263 }
264 
265 static const struct sdhci_ops sdhci_esdhc_ops = {
266 	.read_l = esdhc_readl,
267 	.read_w = esdhc_readw,
268 	.read_b = esdhc_readb,
269 	.write_l = esdhc_writel,
270 	.write_w = esdhc_writew,
271 	.write_b = esdhc_writeb,
272 	.set_clock = esdhc_of_set_clock,
273 	.enable_dma = esdhc_of_enable_dma,
274 	.get_max_clock = esdhc_of_get_max_clock,
275 	.get_min_clock = esdhc_of_get_min_clock,
276 	.platform_init = esdhc_of_platform_init,
277 #ifdef CONFIG_PM
278 	.platform_suspend = esdhc_of_suspend,
279 	.platform_resume = esdhc_of_resume,
280 #endif
281 	.adma_workaround = esdhci_of_adma_workaround,
282 	.platform_bus_width = esdhc_pltfm_bus_width,
283 };
284 
285 static const struct sdhci_pltfm_data sdhci_esdhc_pdata = {
286 	/*
287 	 * card detection could be handled via GPIO
288 	 * eSDHC cannot support End Attribute in NOP ADMA descriptor
289 	 */
290 	.quirks = ESDHC_DEFAULT_QUIRKS | SDHCI_QUIRK_BROKEN_CARD_DETECTION
291 		| SDHCI_QUIRK_NO_CARD_NO_RESET
292 		| SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC,
293 	.ops = &sdhci_esdhc_ops,
294 };
295 
296 static int sdhci_esdhc_probe(struct platform_device *pdev)
297 {
298 	struct sdhci_host *host;
299 	struct device_node *np;
300 	int ret;
301 
302 	host = sdhci_pltfm_init(pdev, &sdhci_esdhc_pdata, 0);
303 	if (IS_ERR(host))
304 		return PTR_ERR(host);
305 
306 	sdhci_get_of_property(pdev);
307 
308 	np = pdev->dev.of_node;
309 	if (of_device_is_compatible(np, "fsl,p2020-esdhc")) {
310 		/*
311 		 * Freescale messed up with P2020 as it has a non-standard
312 		 * host control register
313 		 */
314 		host->quirks2 |= SDHCI_QUIRK2_BROKEN_HOST_CONTROL;
315 	}
316 
317 	/* call to generic mmc_of_parse to support additional capabilities */
318 	mmc_of_parse(host->mmc);
319 	mmc_of_parse_voltage(np, &host->ocr_mask);
320 
321 	ret = sdhci_add_host(host);
322 	if (ret)
323 		sdhci_pltfm_free(pdev);
324 
325 	return ret;
326 }
327 
328 static int sdhci_esdhc_remove(struct platform_device *pdev)
329 {
330 	return sdhci_pltfm_unregister(pdev);
331 }
332 
333 static const struct of_device_id sdhci_esdhc_of_match[] = {
334 	{ .compatible = "fsl,mpc8379-esdhc" },
335 	{ .compatible = "fsl,mpc8536-esdhc" },
336 	{ .compatible = "fsl,esdhc" },
337 	{ }
338 };
339 MODULE_DEVICE_TABLE(of, sdhci_esdhc_of_match);
340 
341 static struct platform_driver sdhci_esdhc_driver = {
342 	.driver = {
343 		.name = "sdhci-esdhc",
344 		.owner = THIS_MODULE,
345 		.of_match_table = sdhci_esdhc_of_match,
346 		.pm = SDHCI_PLTFM_PMOPS,
347 	},
348 	.probe = sdhci_esdhc_probe,
349 	.remove = sdhci_esdhc_remove,
350 };
351 
352 module_platform_driver(sdhci_esdhc_driver);
353 
354 MODULE_DESCRIPTION("SDHCI OF driver for Freescale MPC eSDHC");
355 MODULE_AUTHOR("Xiaobo Xie <X.Xie@freescale.com>, "
356 	      "Anton Vorontsov <avorontsov@ru.mvista.com>");
357 MODULE_LICENSE("GPL v2");
358