xref: /linux/drivers/mmc/host/sdhci-iproc.c (revision d6a5c562214f26e442c8ec3ff1e28e16675d1bcf)
1 // SPDX-License-Identifier: GPL-2.0-only
2 // Copyright (C) 2014 Broadcom Corporation
3 
4 /*
5  * iProc SDHCI platform driver
6  */
7 
8 #include <linux/acpi.h>
9 #include <linux/delay.h>
10 #include <linux/module.h>
11 #include <linux/mmc/host.h>
12 #include <linux/of.h>
13 #include <linux/of_device.h>
14 #include "sdhci-pltfm.h"
15 
16 struct sdhci_iproc_data {
17 	const struct sdhci_pltfm_data *pdata;
18 	u32 caps;
19 	u32 caps1;
20 	u32 mmc_caps;
21 };
22 
23 struct sdhci_iproc_host {
24 	const struct sdhci_iproc_data *data;
25 	u32 shadow_cmd;
26 	u32 shadow_blk;
27 	bool is_cmd_shadowed;
28 	bool is_blk_shadowed;
29 };
30 
31 #define REG_OFFSET_IN_BITS(reg) ((reg) << 3 & 0x18)
32 
33 static inline u32 sdhci_iproc_readl(struct sdhci_host *host, int reg)
34 {
35 	u32 val = readl(host->ioaddr + reg);
36 
37 	pr_debug("%s: readl [0x%02x] 0x%08x\n",
38 		 mmc_hostname(host->mmc), reg, val);
39 	return val;
40 }
41 
42 static u16 sdhci_iproc_readw(struct sdhci_host *host, int reg)
43 {
44 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
45 	struct sdhci_iproc_host *iproc_host = sdhci_pltfm_priv(pltfm_host);
46 	u32 val;
47 	u16 word;
48 
49 	if ((reg == SDHCI_TRANSFER_MODE) && iproc_host->is_cmd_shadowed) {
50 		/* Get the saved transfer mode */
51 		val = iproc_host->shadow_cmd;
52 	} else if ((reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) &&
53 		   iproc_host->is_blk_shadowed) {
54 		/* Get the saved block info */
55 		val = iproc_host->shadow_blk;
56 	} else {
57 		val = sdhci_iproc_readl(host, (reg & ~3));
58 	}
59 	word = val >> REG_OFFSET_IN_BITS(reg) & 0xffff;
60 	return word;
61 }
62 
63 static u8 sdhci_iproc_readb(struct sdhci_host *host, int reg)
64 {
65 	u32 val = sdhci_iproc_readl(host, (reg & ~3));
66 	u8 byte = val >> REG_OFFSET_IN_BITS(reg) & 0xff;
67 	return byte;
68 }
69 
70 static inline void sdhci_iproc_writel(struct sdhci_host *host, u32 val, int reg)
71 {
72 	pr_debug("%s: writel [0x%02x] 0x%08x\n",
73 		 mmc_hostname(host->mmc), reg, val);
74 
75 	writel(val, host->ioaddr + reg);
76 
77 	if (host->clock <= 400000) {
78 		/* Round up to micro-second four SD clock delay */
79 		if (host->clock)
80 			udelay((4 * 1000000 + host->clock - 1) / host->clock);
81 		else
82 			udelay(10);
83 	}
84 }
85 
86 /*
87  * The Arasan has a bugette whereby it may lose the content of successive
88  * writes to the same register that are within two SD-card clock cycles of
89  * each other (a clock domain crossing problem). The data
90  * register does not have this problem, which is just as well - otherwise we'd
91  * have to nobble the DMA engine too.
92  *
93  * This wouldn't be a problem with the code except that we can only write the
94  * controller with 32-bit writes.  So two different 16-bit registers are
95  * written back to back creates the problem.
96  *
97  * In reality, this only happens when SDHCI_BLOCK_SIZE and SDHCI_BLOCK_COUNT
98  * are written followed by SDHCI_TRANSFER_MODE and SDHCI_COMMAND.
99  * The BLOCK_SIZE and BLOCK_COUNT are meaningless until a command issued so
100  * the work around can be further optimized. We can keep shadow values of
101  * BLOCK_SIZE, BLOCK_COUNT, and TRANSFER_MODE until a COMMAND is issued.
102  * Then, write the BLOCK_SIZE+BLOCK_COUNT in a single 32-bit write followed
103  * by the TRANSFER+COMMAND in another 32-bit write.
104  */
105 static void sdhci_iproc_writew(struct sdhci_host *host, u16 val, int reg)
106 {
107 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
108 	struct sdhci_iproc_host *iproc_host = sdhci_pltfm_priv(pltfm_host);
109 	u32 word_shift = REG_OFFSET_IN_BITS(reg);
110 	u32 mask = 0xffff << word_shift;
111 	u32 oldval, newval;
112 
113 	if (reg == SDHCI_COMMAND) {
114 		/* Write the block now as we are issuing a command */
115 		if (iproc_host->is_blk_shadowed) {
116 			sdhci_iproc_writel(host, iproc_host->shadow_blk,
117 				SDHCI_BLOCK_SIZE);
118 			iproc_host->is_blk_shadowed = false;
119 		}
120 		oldval = iproc_host->shadow_cmd;
121 		iproc_host->is_cmd_shadowed = false;
122 	} else if ((reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) &&
123 		   iproc_host->is_blk_shadowed) {
124 		/* Block size and count are stored in shadow reg */
125 		oldval = iproc_host->shadow_blk;
126 	} else {
127 		/* Read reg, all other registers are not shadowed */
128 		oldval = sdhci_iproc_readl(host, (reg & ~3));
129 	}
130 	newval = (oldval & ~mask) | (val << word_shift);
131 
132 	if (reg == SDHCI_TRANSFER_MODE) {
133 		/* Save the transfer mode until the command is issued */
134 		iproc_host->shadow_cmd = newval;
135 		iproc_host->is_cmd_shadowed = true;
136 	} else if (reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) {
137 		/* Save the block info until the command is issued */
138 		iproc_host->shadow_blk = newval;
139 		iproc_host->is_blk_shadowed = true;
140 	} else {
141 		/* Command or other regular 32-bit write */
142 		sdhci_iproc_writel(host, newval, reg & ~3);
143 	}
144 }
145 
146 static void sdhci_iproc_writeb(struct sdhci_host *host, u8 val, int reg)
147 {
148 	u32 oldval = sdhci_iproc_readl(host, (reg & ~3));
149 	u32 byte_shift = REG_OFFSET_IN_BITS(reg);
150 	u32 mask = 0xff << byte_shift;
151 	u32 newval = (oldval & ~mask) | (val << byte_shift);
152 
153 	sdhci_iproc_writel(host, newval, reg & ~3);
154 }
155 
156 static unsigned int sdhci_iproc_get_max_clock(struct sdhci_host *host)
157 {
158 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
159 
160 	if (pltfm_host->clk)
161 		return sdhci_pltfm_clk_get_max_clock(host);
162 	else
163 		return pltfm_host->clock;
164 }
165 
166 /*
167  * There is a known bug on BCM2711's SDHCI core integration where the
168  * controller will hang when the difference between the core clock and the bus
169  * clock is too great. Specifically this can be reproduced under the following
170  * conditions:
171  *
172  *  - No SD card plugged in, polling thread is running, probing cards at
173  *    100 kHz.
174  *  - BCM2711's core clock configured at 500MHz or more
175  *
176  * So we set 200kHz as the minimum clock frequency available for that SoC.
177  */
178 static unsigned int sdhci_iproc_bcm2711_get_min_clock(struct sdhci_host *host)
179 {
180 	return 200000;
181 }
182 
183 static const struct sdhci_ops sdhci_iproc_ops = {
184 	.set_clock = sdhci_set_clock,
185 	.get_max_clock = sdhci_iproc_get_max_clock,
186 	.set_bus_width = sdhci_set_bus_width,
187 	.reset = sdhci_reset,
188 	.set_uhs_signaling = sdhci_set_uhs_signaling,
189 };
190 
191 static const struct sdhci_ops sdhci_iproc_32only_ops = {
192 	.read_l = sdhci_iproc_readl,
193 	.read_w = sdhci_iproc_readw,
194 	.read_b = sdhci_iproc_readb,
195 	.write_l = sdhci_iproc_writel,
196 	.write_w = sdhci_iproc_writew,
197 	.write_b = sdhci_iproc_writeb,
198 	.set_clock = sdhci_set_clock,
199 	.get_max_clock = sdhci_iproc_get_max_clock,
200 	.set_bus_width = sdhci_set_bus_width,
201 	.reset = sdhci_reset,
202 	.set_uhs_signaling = sdhci_set_uhs_signaling,
203 };
204 
205 static const struct sdhci_pltfm_data sdhci_iproc_cygnus_pltfm_data = {
206 	.quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
207 		  SDHCI_QUIRK_NO_HISPD_BIT,
208 	.quirks2 = SDHCI_QUIRK2_ACMD23_BROKEN | SDHCI_QUIRK2_HOST_OFF_CARD_ON,
209 	.ops = &sdhci_iproc_32only_ops,
210 };
211 
212 static const struct sdhci_iproc_data iproc_cygnus_data = {
213 	.pdata = &sdhci_iproc_cygnus_pltfm_data,
214 	.caps = ((0x1 << SDHCI_MAX_BLOCK_SHIFT)
215 			& SDHCI_MAX_BLOCK_MASK) |
216 		SDHCI_CAN_VDD_330 |
217 		SDHCI_CAN_VDD_180 |
218 		SDHCI_CAN_DO_SUSPEND |
219 		SDHCI_CAN_DO_HISPD |
220 		SDHCI_CAN_DO_ADMA2 |
221 		SDHCI_CAN_DO_SDMA,
222 	.caps1 = SDHCI_DRIVER_TYPE_C |
223 		 SDHCI_DRIVER_TYPE_D |
224 		 SDHCI_SUPPORT_DDR50,
225 	.mmc_caps = MMC_CAP_1_8V_DDR,
226 };
227 
228 static const struct sdhci_pltfm_data sdhci_iproc_pltfm_data = {
229 	.quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
230 		  SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12 |
231 		  SDHCI_QUIRK_NO_HISPD_BIT,
232 	.quirks2 = SDHCI_QUIRK2_ACMD23_BROKEN,
233 	.ops = &sdhci_iproc_ops,
234 };
235 
236 static const struct sdhci_iproc_data iproc_data = {
237 	.pdata = &sdhci_iproc_pltfm_data,
238 	.caps = ((0x1 << SDHCI_MAX_BLOCK_SHIFT)
239 			& SDHCI_MAX_BLOCK_MASK) |
240 		SDHCI_CAN_VDD_330 |
241 		SDHCI_CAN_VDD_180 |
242 		SDHCI_CAN_DO_SUSPEND |
243 		SDHCI_CAN_DO_HISPD |
244 		SDHCI_CAN_DO_ADMA2 |
245 		SDHCI_CAN_DO_SDMA,
246 	.caps1 = SDHCI_DRIVER_TYPE_C |
247 		 SDHCI_DRIVER_TYPE_D |
248 		 SDHCI_SUPPORT_DDR50,
249 };
250 
251 static const struct sdhci_pltfm_data sdhci_bcm2835_pltfm_data = {
252 	.quirks = SDHCI_QUIRK_BROKEN_CARD_DETECTION |
253 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
254 		  SDHCI_QUIRK_MISSING_CAPS |
255 		  SDHCI_QUIRK_NO_HISPD_BIT,
256 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
257 	.ops = &sdhci_iproc_32only_ops,
258 };
259 
260 static const struct sdhci_iproc_data bcm2835_data = {
261 	.pdata = &sdhci_bcm2835_pltfm_data,
262 	.caps = ((0x1 << SDHCI_MAX_BLOCK_SHIFT)
263 			& SDHCI_MAX_BLOCK_MASK) |
264 		SDHCI_CAN_VDD_330 |
265 		SDHCI_CAN_DO_HISPD,
266 	.caps1 = SDHCI_DRIVER_TYPE_A |
267 		 SDHCI_DRIVER_TYPE_C,
268 	.mmc_caps = 0x00000000,
269 };
270 
271 static const struct sdhci_ops sdhci_iproc_bcm2711_ops = {
272 	.read_l = sdhci_iproc_readl,
273 	.read_w = sdhci_iproc_readw,
274 	.read_b = sdhci_iproc_readb,
275 	.write_l = sdhci_iproc_writel,
276 	.write_w = sdhci_iproc_writew,
277 	.write_b = sdhci_iproc_writeb,
278 	.set_clock = sdhci_set_clock,
279 	.set_power = sdhci_set_power_and_bus_voltage,
280 	.get_max_clock = sdhci_iproc_get_max_clock,
281 	.get_min_clock = sdhci_iproc_bcm2711_get_min_clock,
282 	.set_bus_width = sdhci_set_bus_width,
283 	.reset = sdhci_reset,
284 	.set_uhs_signaling = sdhci_set_uhs_signaling,
285 };
286 
287 static const struct sdhci_pltfm_data sdhci_bcm2711_pltfm_data = {
288 	.quirks = SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12,
289 	.ops = &sdhci_iproc_bcm2711_ops,
290 };
291 
292 static const struct sdhci_iproc_data bcm2711_data = {
293 	.pdata = &sdhci_bcm2711_pltfm_data,
294 	.mmc_caps = MMC_CAP_3_3V_DDR,
295 };
296 
297 static const struct sdhci_pltfm_data sdhci_bcm7211a0_pltfm_data = {
298 	.quirks = SDHCI_QUIRK_MISSING_CAPS |
299 		SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
300 		SDHCI_QUIRK_BROKEN_DMA |
301 		SDHCI_QUIRK_BROKEN_ADMA,
302 	.ops = &sdhci_iproc_ops,
303 };
304 
305 #define BCM7211A0_BASE_CLK_MHZ 100
306 static const struct sdhci_iproc_data bcm7211a0_data = {
307 	.pdata = &sdhci_bcm7211a0_pltfm_data,
308 	.caps = ((BCM7211A0_BASE_CLK_MHZ / 2) << SDHCI_TIMEOUT_CLK_SHIFT) |
309 		(BCM7211A0_BASE_CLK_MHZ << SDHCI_CLOCK_BASE_SHIFT) |
310 		((0x2 << SDHCI_MAX_BLOCK_SHIFT)
311 			& SDHCI_MAX_BLOCK_MASK) |
312 		SDHCI_CAN_VDD_330 |
313 		SDHCI_CAN_VDD_180 |
314 		SDHCI_CAN_DO_SUSPEND |
315 		SDHCI_CAN_DO_HISPD,
316 	.caps1 = SDHCI_DRIVER_TYPE_C |
317 		 SDHCI_DRIVER_TYPE_D,
318 };
319 
320 static const struct of_device_id sdhci_iproc_of_match[] = {
321 	{ .compatible = "brcm,bcm2835-sdhci", .data = &bcm2835_data },
322 	{ .compatible = "brcm,bcm2711-emmc2", .data = &bcm2711_data },
323 	{ .compatible = "brcm,sdhci-iproc-cygnus", .data = &iproc_cygnus_data},
324 	{ .compatible = "brcm,sdhci-iproc", .data = &iproc_data },
325 	{ .compatible = "brcm,bcm7211a0-sdhci", .data = &bcm7211a0_data },
326 	{ }
327 };
328 MODULE_DEVICE_TABLE(of, sdhci_iproc_of_match);
329 
330 #ifdef CONFIG_ACPI
331 /*
332  * This is a duplicate of bcm2835_(pltfrm_)data without caps quirks
333  * which are provided by the ACPI table.
334  */
335 static const struct sdhci_pltfm_data sdhci_bcm_arasan_data = {
336 	.quirks = SDHCI_QUIRK_BROKEN_CARD_DETECTION |
337 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
338 		  SDHCI_QUIRK_NO_HISPD_BIT,
339 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
340 	.ops = &sdhci_iproc_32only_ops,
341 };
342 
343 static const struct sdhci_iproc_data bcm_arasan_data = {
344 	.pdata = &sdhci_bcm_arasan_data,
345 };
346 
347 static const struct acpi_device_id sdhci_iproc_acpi_ids[] = {
348 	{ .id = "BRCM5871", .driver_data = (kernel_ulong_t)&iproc_cygnus_data },
349 	{ .id = "BRCM5872", .driver_data = (kernel_ulong_t)&iproc_data },
350 	{ .id = "BCM2847",  .driver_data = (kernel_ulong_t)&bcm_arasan_data },
351 	{ .id = "BRCME88C", .driver_data = (kernel_ulong_t)&bcm2711_data },
352 	{ /* sentinel */ }
353 };
354 MODULE_DEVICE_TABLE(acpi, sdhci_iproc_acpi_ids);
355 #endif
356 
357 static int sdhci_iproc_probe(struct platform_device *pdev)
358 {
359 	struct device *dev = &pdev->dev;
360 	const struct sdhci_iproc_data *iproc_data = NULL;
361 	struct sdhci_host *host;
362 	struct sdhci_iproc_host *iproc_host;
363 	struct sdhci_pltfm_host *pltfm_host;
364 	int ret;
365 
366 	iproc_data = device_get_match_data(dev);
367 	if (!iproc_data)
368 		return -ENODEV;
369 
370 	host = sdhci_pltfm_init(pdev, iproc_data->pdata, sizeof(*iproc_host));
371 	if (IS_ERR(host))
372 		return PTR_ERR(host);
373 
374 	pltfm_host = sdhci_priv(host);
375 	iproc_host = sdhci_pltfm_priv(pltfm_host);
376 
377 	iproc_host->data = iproc_data;
378 
379 	ret = mmc_of_parse(host->mmc);
380 	if (ret)
381 		goto err;
382 
383 	sdhci_get_property(pdev);
384 
385 	host->mmc->caps |= iproc_host->data->mmc_caps;
386 
387 	if (dev->of_node) {
388 		pltfm_host->clk = devm_clk_get(dev, NULL);
389 		if (IS_ERR(pltfm_host->clk)) {
390 			ret = PTR_ERR(pltfm_host->clk);
391 			goto err;
392 		}
393 		ret = clk_prepare_enable(pltfm_host->clk);
394 		if (ret) {
395 			dev_err(dev, "failed to enable host clk\n");
396 			goto err;
397 		}
398 	}
399 
400 	if (iproc_host->data->pdata->quirks & SDHCI_QUIRK_MISSING_CAPS) {
401 		host->caps = iproc_host->data->caps;
402 		host->caps1 = iproc_host->data->caps1;
403 	}
404 
405 	ret = sdhci_add_host(host);
406 	if (ret)
407 		goto err_clk;
408 
409 	return 0;
410 
411 err_clk:
412 	if (dev->of_node)
413 		clk_disable_unprepare(pltfm_host->clk);
414 err:
415 	sdhci_pltfm_free(pdev);
416 	return ret;
417 }
418 
419 static void sdhci_iproc_shutdown(struct platform_device *pdev)
420 {
421 	sdhci_pltfm_suspend(&pdev->dev);
422 }
423 
424 static struct platform_driver sdhci_iproc_driver = {
425 	.driver = {
426 		.name = "sdhci-iproc",
427 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
428 		.of_match_table = sdhci_iproc_of_match,
429 		.acpi_match_table = ACPI_PTR(sdhci_iproc_acpi_ids),
430 		.pm = &sdhci_pltfm_pmops,
431 	},
432 	.probe = sdhci_iproc_probe,
433 	.remove = sdhci_pltfm_unregister,
434 	.shutdown = sdhci_iproc_shutdown,
435 };
436 module_platform_driver(sdhci_iproc_driver);
437 
438 MODULE_AUTHOR("Broadcom");
439 MODULE_DESCRIPTION("IPROC SDHCI driver");
440 MODULE_LICENSE("GPL v2");
441