xref: /openbmc/linux/drivers/mmc/host/sdhci-iproc.c (revision da1d9caf)
1 /*
2  * Copyright (C) 2014 Broadcom Corporation
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation version 2.
7  *
8  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
9  * kind, whether express or implied; without even the implied warranty
10  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  */
13 
14 /*
15  * iProc SDHCI platform driver
16  */
17 
18 #include <linux/acpi.h>
19 #include <linux/delay.h>
20 #include <linux/module.h>
21 #include <linux/mmc/host.h>
22 #include <linux/of.h>
23 #include <linux/of_device.h>
24 #include "sdhci-pltfm.h"
25 
26 struct sdhci_iproc_data {
27 	const struct sdhci_pltfm_data *pdata;
28 	u32 caps;
29 	u32 caps1;
30 	u32 mmc_caps;
31 };
32 
33 struct sdhci_iproc_host {
34 	const struct sdhci_iproc_data *data;
35 	u32 shadow_cmd;
36 	u32 shadow_blk;
37 	bool is_cmd_shadowed;
38 	bool is_blk_shadowed;
39 };
40 
41 #define REG_OFFSET_IN_BITS(reg) ((reg) << 3 & 0x18)
42 
43 static inline u32 sdhci_iproc_readl(struct sdhci_host *host, int reg)
44 {
45 	u32 val = readl(host->ioaddr + reg);
46 
47 	pr_debug("%s: readl [0x%02x] 0x%08x\n",
48 		 mmc_hostname(host->mmc), reg, val);
49 	return val;
50 }
51 
52 static u16 sdhci_iproc_readw(struct sdhci_host *host, int reg)
53 {
54 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
55 	struct sdhci_iproc_host *iproc_host = sdhci_pltfm_priv(pltfm_host);
56 	u32 val;
57 	u16 word;
58 
59 	if ((reg == SDHCI_TRANSFER_MODE) && iproc_host->is_cmd_shadowed) {
60 		/* Get the saved transfer mode */
61 		val = iproc_host->shadow_cmd;
62 	} else if ((reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) &&
63 		   iproc_host->is_blk_shadowed) {
64 		/* Get the saved block info */
65 		val = iproc_host->shadow_blk;
66 	} else {
67 		val = sdhci_iproc_readl(host, (reg & ~3));
68 	}
69 	word = val >> REG_OFFSET_IN_BITS(reg) & 0xffff;
70 	return word;
71 }
72 
73 static u8 sdhci_iproc_readb(struct sdhci_host *host, int reg)
74 {
75 	u32 val = sdhci_iproc_readl(host, (reg & ~3));
76 	u8 byte = val >> REG_OFFSET_IN_BITS(reg) & 0xff;
77 	return byte;
78 }
79 
80 static inline void sdhci_iproc_writel(struct sdhci_host *host, u32 val, int reg)
81 {
82 	pr_debug("%s: writel [0x%02x] 0x%08x\n",
83 		 mmc_hostname(host->mmc), reg, val);
84 
85 	writel(val, host->ioaddr + reg);
86 
87 	if (host->clock <= 400000) {
88 		/* Round up to micro-second four SD clock delay */
89 		if (host->clock)
90 			udelay((4 * 1000000 + host->clock - 1) / host->clock);
91 		else
92 			udelay(10);
93 	}
94 }
95 
96 /*
97  * The Arasan has a bugette whereby it may lose the content of successive
98  * writes to the same register that are within two SD-card clock cycles of
99  * each other (a clock domain crossing problem). The data
100  * register does not have this problem, which is just as well - otherwise we'd
101  * have to nobble the DMA engine too.
102  *
103  * This wouldn't be a problem with the code except that we can only write the
104  * controller with 32-bit writes.  So two different 16-bit registers are
105  * written back to back creates the problem.
106  *
107  * In reality, this only happens when SDHCI_BLOCK_SIZE and SDHCI_BLOCK_COUNT
108  * are written followed by SDHCI_TRANSFER_MODE and SDHCI_COMMAND.
109  * The BLOCK_SIZE and BLOCK_COUNT are meaningless until a command issued so
110  * the work around can be further optimized. We can keep shadow values of
111  * BLOCK_SIZE, BLOCK_COUNT, and TRANSFER_MODE until a COMMAND is issued.
112  * Then, write the BLOCK_SIZE+BLOCK_COUNT in a single 32-bit write followed
113  * by the TRANSFER+COMMAND in another 32-bit write.
114  */
115 static void sdhci_iproc_writew(struct sdhci_host *host, u16 val, int reg)
116 {
117 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
118 	struct sdhci_iproc_host *iproc_host = sdhci_pltfm_priv(pltfm_host);
119 	u32 word_shift = REG_OFFSET_IN_BITS(reg);
120 	u32 mask = 0xffff << word_shift;
121 	u32 oldval, newval;
122 
123 	if (reg == SDHCI_COMMAND) {
124 		/* Write the block now as we are issuing a command */
125 		if (iproc_host->is_blk_shadowed) {
126 			sdhci_iproc_writel(host, iproc_host->shadow_blk,
127 				SDHCI_BLOCK_SIZE);
128 			iproc_host->is_blk_shadowed = false;
129 		}
130 		oldval = iproc_host->shadow_cmd;
131 		iproc_host->is_cmd_shadowed = false;
132 	} else if ((reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) &&
133 		   iproc_host->is_blk_shadowed) {
134 		/* Block size and count are stored in shadow reg */
135 		oldval = iproc_host->shadow_blk;
136 	} else {
137 		/* Read reg, all other registers are not shadowed */
138 		oldval = sdhci_iproc_readl(host, (reg & ~3));
139 	}
140 	newval = (oldval & ~mask) | (val << word_shift);
141 
142 	if (reg == SDHCI_TRANSFER_MODE) {
143 		/* Save the transfer mode until the command is issued */
144 		iproc_host->shadow_cmd = newval;
145 		iproc_host->is_cmd_shadowed = true;
146 	} else if (reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) {
147 		/* Save the block info until the command is issued */
148 		iproc_host->shadow_blk = newval;
149 		iproc_host->is_blk_shadowed = true;
150 	} else {
151 		/* Command or other regular 32-bit write */
152 		sdhci_iproc_writel(host, newval, reg & ~3);
153 	}
154 }
155 
156 static void sdhci_iproc_writeb(struct sdhci_host *host, u8 val, int reg)
157 {
158 	u32 oldval = sdhci_iproc_readl(host, (reg & ~3));
159 	u32 byte_shift = REG_OFFSET_IN_BITS(reg);
160 	u32 mask = 0xff << byte_shift;
161 	u32 newval = (oldval & ~mask) | (val << byte_shift);
162 
163 	sdhci_iproc_writel(host, newval, reg & ~3);
164 }
165 
166 static unsigned int sdhci_iproc_get_max_clock(struct sdhci_host *host)
167 {
168 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
169 
170 	if (pltfm_host->clk)
171 		return sdhci_pltfm_clk_get_max_clock(host);
172 	else
173 		return pltfm_host->clock;
174 }
175 
176 /*
177  * There is a known bug on BCM2711's SDHCI core integration where the
178  * controller will hang when the difference between the core clock and the bus
179  * clock is too great. Specifically this can be reproduced under the following
180  * conditions:
181  *
182  *  - No SD card plugged in, polling thread is running, probing cards at
183  *    100 kHz.
184  *  - BCM2711's core clock configured at 500MHz or more
185  *
186  * So we set 200kHz as the minimum clock frequency available for that SoC.
187  */
188 static unsigned int sdhci_iproc_bcm2711_get_min_clock(struct sdhci_host *host)
189 {
190 	return 200000;
191 }
192 
193 static const struct sdhci_ops sdhci_iproc_ops = {
194 	.set_clock = sdhci_set_clock,
195 	.get_max_clock = sdhci_iproc_get_max_clock,
196 	.set_bus_width = sdhci_set_bus_width,
197 	.reset = sdhci_reset,
198 	.set_uhs_signaling = sdhci_set_uhs_signaling,
199 };
200 
201 static const struct sdhci_ops sdhci_iproc_32only_ops = {
202 	.read_l = sdhci_iproc_readl,
203 	.read_w = sdhci_iproc_readw,
204 	.read_b = sdhci_iproc_readb,
205 	.write_l = sdhci_iproc_writel,
206 	.write_w = sdhci_iproc_writew,
207 	.write_b = sdhci_iproc_writeb,
208 	.set_clock = sdhci_set_clock,
209 	.get_max_clock = sdhci_iproc_get_max_clock,
210 	.set_bus_width = sdhci_set_bus_width,
211 	.reset = sdhci_reset,
212 	.set_uhs_signaling = sdhci_set_uhs_signaling,
213 };
214 
215 static const struct sdhci_pltfm_data sdhci_iproc_cygnus_pltfm_data = {
216 	.quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
217 		  SDHCI_QUIRK_NO_HISPD_BIT,
218 	.quirks2 = SDHCI_QUIRK2_ACMD23_BROKEN | SDHCI_QUIRK2_HOST_OFF_CARD_ON,
219 	.ops = &sdhci_iproc_32only_ops,
220 };
221 
222 static const struct sdhci_iproc_data iproc_cygnus_data = {
223 	.pdata = &sdhci_iproc_cygnus_pltfm_data,
224 	.caps = ((0x1 << SDHCI_MAX_BLOCK_SHIFT)
225 			& SDHCI_MAX_BLOCK_MASK) |
226 		SDHCI_CAN_VDD_330 |
227 		SDHCI_CAN_VDD_180 |
228 		SDHCI_CAN_DO_SUSPEND |
229 		SDHCI_CAN_DO_HISPD |
230 		SDHCI_CAN_DO_ADMA2 |
231 		SDHCI_CAN_DO_SDMA,
232 	.caps1 = SDHCI_DRIVER_TYPE_C |
233 		 SDHCI_DRIVER_TYPE_D |
234 		 SDHCI_SUPPORT_DDR50,
235 	.mmc_caps = MMC_CAP_1_8V_DDR,
236 };
237 
238 static const struct sdhci_pltfm_data sdhci_iproc_pltfm_data = {
239 	.quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
240 		  SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12 |
241 		  SDHCI_QUIRK_NO_HISPD_BIT,
242 	.quirks2 = SDHCI_QUIRK2_ACMD23_BROKEN,
243 	.ops = &sdhci_iproc_ops,
244 };
245 
246 static const struct sdhci_iproc_data iproc_data = {
247 	.pdata = &sdhci_iproc_pltfm_data,
248 	.caps = ((0x1 << SDHCI_MAX_BLOCK_SHIFT)
249 			& SDHCI_MAX_BLOCK_MASK) |
250 		SDHCI_CAN_VDD_330 |
251 		SDHCI_CAN_VDD_180 |
252 		SDHCI_CAN_DO_SUSPEND |
253 		SDHCI_CAN_DO_HISPD |
254 		SDHCI_CAN_DO_ADMA2 |
255 		SDHCI_CAN_DO_SDMA,
256 	.caps1 = SDHCI_DRIVER_TYPE_C |
257 		 SDHCI_DRIVER_TYPE_D |
258 		 SDHCI_SUPPORT_DDR50,
259 };
260 
261 static const struct sdhci_pltfm_data sdhci_bcm2835_pltfm_data = {
262 	.quirks = SDHCI_QUIRK_BROKEN_CARD_DETECTION |
263 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
264 		  SDHCI_QUIRK_MISSING_CAPS |
265 		  SDHCI_QUIRK_NO_HISPD_BIT,
266 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
267 	.ops = &sdhci_iproc_32only_ops,
268 };
269 
270 static const struct sdhci_iproc_data bcm2835_data = {
271 	.pdata = &sdhci_bcm2835_pltfm_data,
272 	.caps = ((0x1 << SDHCI_MAX_BLOCK_SHIFT)
273 			& SDHCI_MAX_BLOCK_MASK) |
274 		SDHCI_CAN_VDD_330 |
275 		SDHCI_CAN_DO_HISPD,
276 	.caps1 = SDHCI_DRIVER_TYPE_A |
277 		 SDHCI_DRIVER_TYPE_C,
278 	.mmc_caps = 0x00000000,
279 };
280 
281 static const struct sdhci_ops sdhci_iproc_bcm2711_ops = {
282 	.read_l = sdhci_iproc_readl,
283 	.read_w = sdhci_iproc_readw,
284 	.read_b = sdhci_iproc_readb,
285 	.write_l = sdhci_iproc_writel,
286 	.write_w = sdhci_iproc_writew,
287 	.write_b = sdhci_iproc_writeb,
288 	.set_clock = sdhci_set_clock,
289 	.set_power = sdhci_set_power_and_bus_voltage,
290 	.get_max_clock = sdhci_iproc_get_max_clock,
291 	.get_min_clock = sdhci_iproc_bcm2711_get_min_clock,
292 	.set_bus_width = sdhci_set_bus_width,
293 	.reset = sdhci_reset,
294 	.set_uhs_signaling = sdhci_set_uhs_signaling,
295 };
296 
297 static const struct sdhci_pltfm_data sdhci_bcm2711_pltfm_data = {
298 	.quirks = SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12,
299 	.ops = &sdhci_iproc_bcm2711_ops,
300 };
301 
302 static const struct sdhci_iproc_data bcm2711_data = {
303 	.pdata = &sdhci_bcm2711_pltfm_data,
304 	.mmc_caps = MMC_CAP_3_3V_DDR,
305 };
306 
307 static const struct sdhci_pltfm_data sdhci_bcm7211a0_pltfm_data = {
308 	.quirks = SDHCI_QUIRK_MISSING_CAPS |
309 		SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
310 		SDHCI_QUIRK_BROKEN_DMA |
311 		SDHCI_QUIRK_BROKEN_ADMA,
312 	.ops = &sdhci_iproc_ops,
313 };
314 
315 #define BCM7211A0_BASE_CLK_MHZ 100
316 static const struct sdhci_iproc_data bcm7211a0_data = {
317 	.pdata = &sdhci_bcm7211a0_pltfm_data,
318 	.caps = ((BCM7211A0_BASE_CLK_MHZ / 2) << SDHCI_TIMEOUT_CLK_SHIFT) |
319 		(BCM7211A0_BASE_CLK_MHZ << SDHCI_CLOCK_BASE_SHIFT) |
320 		((0x2 << SDHCI_MAX_BLOCK_SHIFT)
321 			& SDHCI_MAX_BLOCK_MASK) |
322 		SDHCI_CAN_VDD_330 |
323 		SDHCI_CAN_VDD_180 |
324 		SDHCI_CAN_DO_SUSPEND |
325 		SDHCI_CAN_DO_HISPD,
326 	.caps1 = SDHCI_DRIVER_TYPE_C |
327 		 SDHCI_DRIVER_TYPE_D,
328 };
329 
330 static const struct of_device_id sdhci_iproc_of_match[] = {
331 	{ .compatible = "brcm,bcm2835-sdhci", .data = &bcm2835_data },
332 	{ .compatible = "brcm,bcm2711-emmc2", .data = &bcm2711_data },
333 	{ .compatible = "brcm,sdhci-iproc-cygnus", .data = &iproc_cygnus_data},
334 	{ .compatible = "brcm,sdhci-iproc", .data = &iproc_data },
335 	{ .compatible = "brcm,bcm7211a0-sdhci", .data = &bcm7211a0_data },
336 	{ }
337 };
338 MODULE_DEVICE_TABLE(of, sdhci_iproc_of_match);
339 
340 #ifdef CONFIG_ACPI
341 /*
342  * This is a duplicate of bcm2835_(pltfrm_)data without caps quirks
343  * which are provided by the ACPI table.
344  */
345 static const struct sdhci_pltfm_data sdhci_bcm_arasan_data = {
346 	.quirks = SDHCI_QUIRK_BROKEN_CARD_DETECTION |
347 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
348 		  SDHCI_QUIRK_NO_HISPD_BIT,
349 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
350 	.ops = &sdhci_iproc_32only_ops,
351 };
352 
353 static const struct sdhci_iproc_data bcm_arasan_data = {
354 	.pdata = &sdhci_bcm_arasan_data,
355 };
356 
357 static const struct acpi_device_id sdhci_iproc_acpi_ids[] = {
358 	{ .id = "BRCM5871", .driver_data = (kernel_ulong_t)&iproc_cygnus_data },
359 	{ .id = "BRCM5872", .driver_data = (kernel_ulong_t)&iproc_data },
360 	{ .id = "BCM2847",  .driver_data = (kernel_ulong_t)&bcm_arasan_data },
361 	{ .id = "BRCME88C", .driver_data = (kernel_ulong_t)&bcm2711_data },
362 	{ /* sentinel */ }
363 };
364 MODULE_DEVICE_TABLE(acpi, sdhci_iproc_acpi_ids);
365 #endif
366 
367 static int sdhci_iproc_probe(struct platform_device *pdev)
368 {
369 	struct device *dev = &pdev->dev;
370 	const struct sdhci_iproc_data *iproc_data = NULL;
371 	struct sdhci_host *host;
372 	struct sdhci_iproc_host *iproc_host;
373 	struct sdhci_pltfm_host *pltfm_host;
374 	int ret;
375 
376 	iproc_data = device_get_match_data(dev);
377 	if (!iproc_data)
378 		return -ENODEV;
379 
380 	host = sdhci_pltfm_init(pdev, iproc_data->pdata, sizeof(*iproc_host));
381 	if (IS_ERR(host))
382 		return PTR_ERR(host);
383 
384 	pltfm_host = sdhci_priv(host);
385 	iproc_host = sdhci_pltfm_priv(pltfm_host);
386 
387 	iproc_host->data = iproc_data;
388 
389 	ret = mmc_of_parse(host->mmc);
390 	if (ret)
391 		goto err;
392 
393 	sdhci_get_property(pdev);
394 
395 	host->mmc->caps |= iproc_host->data->mmc_caps;
396 
397 	if (dev->of_node) {
398 		pltfm_host->clk = devm_clk_get(dev, NULL);
399 		if (IS_ERR(pltfm_host->clk)) {
400 			ret = PTR_ERR(pltfm_host->clk);
401 			goto err;
402 		}
403 		ret = clk_prepare_enable(pltfm_host->clk);
404 		if (ret) {
405 			dev_err(dev, "failed to enable host clk\n");
406 			goto err;
407 		}
408 	}
409 
410 	if (iproc_host->data->pdata->quirks & SDHCI_QUIRK_MISSING_CAPS) {
411 		host->caps = iproc_host->data->caps;
412 		host->caps1 = iproc_host->data->caps1;
413 	}
414 
415 	ret = sdhci_add_host(host);
416 	if (ret)
417 		goto err_clk;
418 
419 	return 0;
420 
421 err_clk:
422 	if (dev->of_node)
423 		clk_disable_unprepare(pltfm_host->clk);
424 err:
425 	sdhci_pltfm_free(pdev);
426 	return ret;
427 }
428 
429 static void sdhci_iproc_shutdown(struct platform_device *pdev)
430 {
431 	sdhci_pltfm_suspend(&pdev->dev);
432 }
433 
434 static struct platform_driver sdhci_iproc_driver = {
435 	.driver = {
436 		.name = "sdhci-iproc",
437 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
438 		.of_match_table = sdhci_iproc_of_match,
439 		.acpi_match_table = ACPI_PTR(sdhci_iproc_acpi_ids),
440 		.pm = &sdhci_pltfm_pmops,
441 	},
442 	.probe = sdhci_iproc_probe,
443 	.remove = sdhci_pltfm_unregister,
444 	.shutdown = sdhci_iproc_shutdown,
445 };
446 module_platform_driver(sdhci_iproc_driver);
447 
448 MODULE_AUTHOR("Broadcom");
449 MODULE_DESCRIPTION("IPROC SDHCI driver");
450 MODULE_LICENSE("GPL v2");
451