xref: /linux/drivers/mmc/host/sdhci-brcmstb.c (revision 151ebcf0797b1a3ba53c8843dc21748c80e098c7)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * sdhci-brcmstb.c Support for SDHCI on Broadcom BRCMSTB SoC's
4  *
5  * Copyright (C) 2015 Broadcom Corporation
6  */
7 
8 #include <linux/io.h>
9 #include <linux/iopoll.h>
10 #include <linux/mmc/host.h>
11 #include <linux/module.h>
12 #include <linux/of.h>
13 #include <linux/bitops.h>
14 #include <linux/delay.h>
15 
16 #include "sdhci-cqhci.h"
17 #include "sdhci-pltfm.h"
18 #include "cqhci.h"
19 
20 #define SDHCI_VENDOR 0x78
21 #define  SDHCI_VENDOR_ENHANCED_STRB 0x1
22 #define  SDHCI_VENDOR_GATE_SDCLK_EN 0x2
23 
24 #define BRCMSTB_MATCH_FLAGS_NO_64BIT		BIT(0)
25 #define BRCMSTB_MATCH_FLAGS_BROKEN_TIMEOUT	BIT(1)
26 #define BRCMSTB_MATCH_FLAGS_HAS_CLOCK_GATE	BIT(2)
27 #define BRCMSTB_MATCH_FLAGS_USE_CARD_BUSY	BIT(4)
28 
29 #define BRCMSTB_PRIV_FLAGS_HAS_CQE		BIT(0)
30 #define BRCMSTB_PRIV_FLAGS_GATE_CLOCK		BIT(1)
31 
32 #define SDHCI_ARASAN_CQE_BASE_ADDR		0x200
33 
34 struct sdhci_brcmstb_priv {
35 	void __iomem *cfg_regs;
36 	unsigned int flags;
37 	struct clk *base_clk;
38 	u32 base_freq_hz;
39 };
40 
41 struct brcmstb_match_priv {
42 	void (*hs400es)(struct mmc_host *mmc, struct mmc_ios *ios);
43 	struct sdhci_ops *ops;
44 	const unsigned int flags;
45 };
46 
47 static inline void enable_clock_gating(struct sdhci_host *host)
48 {
49 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
50 	struct sdhci_brcmstb_priv *priv = sdhci_pltfm_priv(pltfm_host);
51 	u32 reg;
52 
53 	if (!(priv->flags & BRCMSTB_PRIV_FLAGS_GATE_CLOCK))
54 		return;
55 
56 	reg = sdhci_readl(host, SDHCI_VENDOR);
57 	reg |= SDHCI_VENDOR_GATE_SDCLK_EN;
58 	sdhci_writel(host, reg, SDHCI_VENDOR);
59 }
60 
61 static void brcmstb_reset(struct sdhci_host *host, u8 mask)
62 {
63 	sdhci_and_cqhci_reset(host, mask);
64 
65 	/* Reset will clear this, so re-enable it */
66 	enable_clock_gating(host);
67 }
68 
69 static void brcmstb_sdhci_reset_cmd_data(struct sdhci_host *host, u8 mask)
70 {
71 	u32 new_mask = (mask &  (SDHCI_RESET_CMD | SDHCI_RESET_DATA)) << 24;
72 	int ret;
73 	u32 reg;
74 
75 	/*
76 	 * SDHCI_CLOCK_CONTROL register CARD_EN and CLOCK_INT_EN bits shall
77 	 * be set along with SOFTWARE_RESET register RESET_CMD or RESET_DATA
78 	 * bits, hence access SDHCI_CLOCK_CONTROL register as 32-bit register
79 	 */
80 	new_mask |= SDHCI_CLOCK_CARD_EN | SDHCI_CLOCK_INT_EN;
81 	reg = sdhci_readl(host, SDHCI_CLOCK_CONTROL);
82 	sdhci_writel(host, reg | new_mask, SDHCI_CLOCK_CONTROL);
83 
84 	reg = sdhci_readb(host, SDHCI_SOFTWARE_RESET);
85 
86 	ret = read_poll_timeout_atomic(sdhci_readb, reg, !(reg & mask),
87 				       10, 10000, false,
88 				       host, SDHCI_SOFTWARE_RESET);
89 
90 	if (ret) {
91 		pr_err("%s: Reset 0x%x never completed.\n",
92 		       mmc_hostname(host->mmc), (int)mask);
93 		sdhci_err_stats_inc(host, CTRL_TIMEOUT);
94 		sdhci_dumpregs(host);
95 	}
96 }
97 
98 static void brcmstb_reset_74165b0(struct sdhci_host *host, u8 mask)
99 {
100 	/* take care of RESET_ALL as usual */
101 	if (mask & SDHCI_RESET_ALL)
102 		sdhci_and_cqhci_reset(host, SDHCI_RESET_ALL);
103 
104 	/* cmd and/or data treated differently on this core */
105 	if (mask & (SDHCI_RESET_CMD | SDHCI_RESET_DATA))
106 		brcmstb_sdhci_reset_cmd_data(host, mask);
107 
108 	/* Reset will clear this, so re-enable it */
109 	enable_clock_gating(host);
110 }
111 
112 static void sdhci_brcmstb_hs400es(struct mmc_host *mmc, struct mmc_ios *ios)
113 {
114 	struct sdhci_host *host = mmc_priv(mmc);
115 
116 	u32 reg;
117 
118 	dev_dbg(mmc_dev(mmc), "%s(): Setting HS400-Enhanced-Strobe mode\n",
119 		__func__);
120 	reg = readl(host->ioaddr + SDHCI_VENDOR);
121 	if (ios->enhanced_strobe)
122 		reg |= SDHCI_VENDOR_ENHANCED_STRB;
123 	else
124 		reg &= ~SDHCI_VENDOR_ENHANCED_STRB;
125 	writel(reg, host->ioaddr + SDHCI_VENDOR);
126 }
127 
128 static void sdhci_brcmstb_set_clock(struct sdhci_host *host, unsigned int clock)
129 {
130 	u16 clk;
131 
132 	host->mmc->actual_clock = 0;
133 
134 	clk = sdhci_calc_clk(host, clock, &host->mmc->actual_clock);
135 	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
136 
137 	if (clock == 0)
138 		return;
139 
140 	sdhci_enable_clk(host, clk);
141 }
142 
143 static void sdhci_brcmstb_set_uhs_signaling(struct sdhci_host *host,
144 					    unsigned int timing)
145 {
146 	u16 ctrl_2;
147 
148 	dev_dbg(mmc_dev(host->mmc), "%s: Setting UHS signaling for %d timing\n",
149 		__func__, timing);
150 	ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
151 	/* Select Bus Speed Mode for host */
152 	ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
153 	if ((timing == MMC_TIMING_MMC_HS200) ||
154 	    (timing == MMC_TIMING_UHS_SDR104))
155 		ctrl_2 |= SDHCI_CTRL_UHS_SDR104;
156 	else if (timing == MMC_TIMING_UHS_SDR12)
157 		ctrl_2 |= SDHCI_CTRL_UHS_SDR12;
158 	else if (timing == MMC_TIMING_SD_HS ||
159 		 timing == MMC_TIMING_MMC_HS ||
160 		 timing == MMC_TIMING_UHS_SDR25)
161 		ctrl_2 |= SDHCI_CTRL_UHS_SDR25;
162 	else if (timing == MMC_TIMING_UHS_SDR50)
163 		ctrl_2 |= SDHCI_CTRL_UHS_SDR50;
164 	else if ((timing == MMC_TIMING_UHS_DDR50) ||
165 		 (timing == MMC_TIMING_MMC_DDR52))
166 		ctrl_2 |= SDHCI_CTRL_UHS_DDR50;
167 	else if (timing == MMC_TIMING_MMC_HS400)
168 		ctrl_2 |= SDHCI_CTRL_HS400; /* Non-standard */
169 	sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
170 }
171 
172 static void sdhci_brcmstb_dumpregs(struct mmc_host *mmc)
173 {
174 	sdhci_dumpregs(mmc_priv(mmc));
175 }
176 
177 static void sdhci_brcmstb_cqe_enable(struct mmc_host *mmc)
178 {
179 	struct sdhci_host *host = mmc_priv(mmc);
180 	u32 reg;
181 
182 	reg = sdhci_readl(host, SDHCI_PRESENT_STATE);
183 	while (reg & SDHCI_DATA_AVAILABLE) {
184 		sdhci_readl(host, SDHCI_BUFFER);
185 		reg = sdhci_readl(host, SDHCI_PRESENT_STATE);
186 	}
187 
188 	sdhci_cqe_enable(mmc);
189 }
190 
191 static const struct cqhci_host_ops sdhci_brcmstb_cqhci_ops = {
192 	.enable         = sdhci_brcmstb_cqe_enable,
193 	.disable        = sdhci_cqe_disable,
194 	.dumpregs       = sdhci_brcmstb_dumpregs,
195 };
196 
197 static struct sdhci_ops sdhci_brcmstb_ops = {
198 	.set_clock = sdhci_set_clock,
199 	.set_bus_width = sdhci_set_bus_width,
200 	.reset = sdhci_reset,
201 	.set_uhs_signaling = sdhci_set_uhs_signaling,
202 };
203 
204 static struct sdhci_ops sdhci_brcmstb_ops_7216 = {
205 	.set_clock = sdhci_brcmstb_set_clock,
206 	.set_bus_width = sdhci_set_bus_width,
207 	.reset = brcmstb_reset,
208 	.set_uhs_signaling = sdhci_brcmstb_set_uhs_signaling,
209 };
210 
211 static struct sdhci_ops sdhci_brcmstb_ops_74165b0 = {
212 	.set_clock = sdhci_brcmstb_set_clock,
213 	.set_bus_width = sdhci_set_bus_width,
214 	.reset = brcmstb_reset_74165b0,
215 	.set_uhs_signaling = sdhci_brcmstb_set_uhs_signaling,
216 };
217 
218 static struct brcmstb_match_priv match_priv_7425 = {
219 	.flags = BRCMSTB_MATCH_FLAGS_NO_64BIT |
220 	BRCMSTB_MATCH_FLAGS_BROKEN_TIMEOUT,
221 	.ops = &sdhci_brcmstb_ops,
222 };
223 
224 static struct brcmstb_match_priv match_priv_7445 = {
225 	.flags = BRCMSTB_MATCH_FLAGS_BROKEN_TIMEOUT,
226 	.ops = &sdhci_brcmstb_ops,
227 };
228 
229 static const struct brcmstb_match_priv match_priv_7216 = {
230 	.flags = BRCMSTB_MATCH_FLAGS_HAS_CLOCK_GATE,
231 	.hs400es = sdhci_brcmstb_hs400es,
232 	.ops = &sdhci_brcmstb_ops_7216,
233 };
234 
235 static struct brcmstb_match_priv match_priv_74165b0 = {
236 	.flags = BRCMSTB_MATCH_FLAGS_HAS_CLOCK_GATE,
237 	.hs400es = sdhci_brcmstb_hs400es,
238 	.ops = &sdhci_brcmstb_ops_74165b0,
239 };
240 
241 static const struct of_device_id __maybe_unused sdhci_brcm_of_match[] = {
242 	{ .compatible = "brcm,bcm7425-sdhci", .data = &match_priv_7425 },
243 	{ .compatible = "brcm,bcm7445-sdhci", .data = &match_priv_7445 },
244 	{ .compatible = "brcm,bcm7216-sdhci", .data = &match_priv_7216 },
245 	{ .compatible = "brcm,bcm74165b0-sdhci", .data = &match_priv_74165b0 },
246 	{},
247 };
248 
249 static u32 sdhci_brcmstb_cqhci_irq(struct sdhci_host *host, u32 intmask)
250 {
251 	int cmd_error = 0;
252 	int data_error = 0;
253 
254 	if (!sdhci_cqe_irq(host, intmask, &cmd_error, &data_error))
255 		return intmask;
256 
257 	cqhci_irq(host->mmc, intmask, cmd_error, data_error);
258 
259 	return 0;
260 }
261 
262 static int sdhci_brcmstb_add_host(struct sdhci_host *host,
263 				  struct sdhci_brcmstb_priv *priv)
264 {
265 	struct cqhci_host *cq_host;
266 	bool dma64;
267 	int ret;
268 
269 	if ((priv->flags & BRCMSTB_PRIV_FLAGS_HAS_CQE) == 0)
270 		return sdhci_add_host(host);
271 
272 	dev_dbg(mmc_dev(host->mmc), "CQE is enabled\n");
273 	host->mmc->caps2 |= MMC_CAP2_CQE | MMC_CAP2_CQE_DCMD;
274 	ret = sdhci_setup_host(host);
275 	if (ret)
276 		return ret;
277 
278 	cq_host = devm_kzalloc(mmc_dev(host->mmc),
279 			       sizeof(*cq_host), GFP_KERNEL);
280 	if (!cq_host) {
281 		ret = -ENOMEM;
282 		goto cleanup;
283 	}
284 
285 	cq_host->mmio = host->ioaddr + SDHCI_ARASAN_CQE_BASE_ADDR;
286 	cq_host->ops = &sdhci_brcmstb_cqhci_ops;
287 
288 	dma64 = host->flags & SDHCI_USE_64_BIT_DMA;
289 	if (dma64) {
290 		dev_dbg(mmc_dev(host->mmc), "Using 64 bit DMA\n");
291 		cq_host->caps |= CQHCI_TASK_DESC_SZ_128;
292 	}
293 
294 	ret = cqhci_init(cq_host, host->mmc, dma64);
295 	if (ret)
296 		goto cleanup;
297 
298 	ret = __sdhci_add_host(host);
299 	if (ret)
300 		goto cleanup;
301 
302 	return 0;
303 
304 cleanup:
305 	sdhci_cleanup_host(host);
306 	return ret;
307 }
308 
309 static int sdhci_brcmstb_probe(struct platform_device *pdev)
310 {
311 	const struct brcmstb_match_priv *match_priv;
312 	struct sdhci_pltfm_data brcmstb_pdata;
313 	struct sdhci_pltfm_host *pltfm_host;
314 	const struct of_device_id *match;
315 	struct sdhci_brcmstb_priv *priv;
316 	u32 actual_clock_mhz;
317 	struct sdhci_host *host;
318 	struct clk *clk;
319 	struct clk *base_clk = NULL;
320 	int res;
321 
322 	match = of_match_node(sdhci_brcm_of_match, pdev->dev.of_node);
323 	match_priv = match->data;
324 
325 	dev_dbg(&pdev->dev, "Probe found match for %s\n",  match->compatible);
326 
327 	clk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
328 	if (IS_ERR(clk))
329 		return dev_err_probe(&pdev->dev, PTR_ERR(clk),
330 				     "Failed to get and enable clock from Device Tree\n");
331 
332 	memset(&brcmstb_pdata, 0, sizeof(brcmstb_pdata));
333 	brcmstb_pdata.ops = match_priv->ops;
334 	host = sdhci_pltfm_init(pdev, &brcmstb_pdata,
335 				sizeof(struct sdhci_brcmstb_priv));
336 	if (IS_ERR(host))
337 		return PTR_ERR(host);
338 
339 	pltfm_host = sdhci_priv(host);
340 	priv = sdhci_pltfm_priv(pltfm_host);
341 	if (device_property_read_bool(&pdev->dev, "supports-cqe")) {
342 		priv->flags |= BRCMSTB_PRIV_FLAGS_HAS_CQE;
343 		match_priv->ops->irq = sdhci_brcmstb_cqhci_irq;
344 	}
345 
346 	/* Map in the non-standard CFG registers */
347 	priv->cfg_regs = devm_platform_get_and_ioremap_resource(pdev, 1, NULL);
348 	if (IS_ERR(priv->cfg_regs)) {
349 		res = PTR_ERR(priv->cfg_regs);
350 		goto err;
351 	}
352 
353 	sdhci_get_of_property(pdev);
354 	res = mmc_of_parse(host->mmc);
355 	if (res)
356 		goto err;
357 
358 	/*
359 	 * Automatic clock gating does not work for SD cards that may
360 	 * voltage switch so only enable it for non-removable devices.
361 	 */
362 	if ((match_priv->flags & BRCMSTB_MATCH_FLAGS_HAS_CLOCK_GATE) &&
363 	    (host->mmc->caps & MMC_CAP_NONREMOVABLE))
364 		priv->flags |= BRCMSTB_PRIV_FLAGS_GATE_CLOCK;
365 
366 	/*
367 	 * If the chip has enhanced strobe and it's enabled, add
368 	 * callback
369 	 */
370 	if (match_priv->hs400es &&
371 	    (host->mmc->caps2 & MMC_CAP2_HS400_ES))
372 		host->mmc_host_ops.hs400_enhanced_strobe = match_priv->hs400es;
373 
374 	/*
375 	 * Supply the existing CAPS, but clear the UHS modes. This
376 	 * will allow these modes to be specified by device tree
377 	 * properties through mmc_of_parse().
378 	 */
379 	sdhci_read_caps(host);
380 	if (match_priv->flags & BRCMSTB_MATCH_FLAGS_NO_64BIT)
381 		host->caps &= ~SDHCI_CAN_64BIT;
382 	host->caps1 &= ~(SDHCI_SUPPORT_SDR50 | SDHCI_SUPPORT_SDR104 |
383 			 SDHCI_SUPPORT_DDR50);
384 
385 	if (match_priv->flags & BRCMSTB_MATCH_FLAGS_BROKEN_TIMEOUT)
386 		host->quirks |= SDHCI_QUIRK_BROKEN_TIMEOUT_VAL;
387 
388 	if (!(match_priv->flags & BRCMSTB_MATCH_FLAGS_USE_CARD_BUSY))
389 		host->mmc_host_ops.card_busy = NULL;
390 
391 	/* Change the base clock frequency if the DT property exists */
392 	if (device_property_read_u32(&pdev->dev, "clock-frequency",
393 				     &priv->base_freq_hz) != 0)
394 		goto add_host;
395 
396 	base_clk = devm_clk_get_optional(&pdev->dev, "sdio_freq");
397 	if (IS_ERR(base_clk)) {
398 		dev_warn(&pdev->dev, "Clock for \"sdio_freq\" not found\n");
399 		goto add_host;
400 	}
401 
402 	res = clk_prepare_enable(base_clk);
403 	if (res)
404 		goto err;
405 
406 	/* set improved clock rate */
407 	clk_set_rate(base_clk, priv->base_freq_hz);
408 	actual_clock_mhz = clk_get_rate(base_clk) / 1000000;
409 
410 	host->caps &= ~SDHCI_CLOCK_V3_BASE_MASK;
411 	host->caps |= (actual_clock_mhz << SDHCI_CLOCK_BASE_SHIFT);
412 	/* Disable presets because they are now incorrect */
413 	host->quirks2 |= SDHCI_QUIRK2_PRESET_VALUE_BROKEN;
414 
415 	dev_dbg(&pdev->dev, "Base Clock Frequency changed to %dMHz\n",
416 		actual_clock_mhz);
417 	priv->base_clk = base_clk;
418 
419 add_host:
420 	res = sdhci_brcmstb_add_host(host, priv);
421 	if (res)
422 		goto err;
423 
424 	pltfm_host->clk = clk;
425 	return res;
426 
427 err:
428 	sdhci_pltfm_free(pdev);
429 	clk_disable_unprepare(base_clk);
430 	return res;
431 }
432 
433 static void sdhci_brcmstb_shutdown(struct platform_device *pdev)
434 {
435 	sdhci_pltfm_suspend(&pdev->dev);
436 }
437 
438 MODULE_DEVICE_TABLE(of, sdhci_brcm_of_match);
439 
440 #ifdef CONFIG_PM_SLEEP
441 static int sdhci_brcmstb_suspend(struct device *dev)
442 {
443 	struct sdhci_host *host = dev_get_drvdata(dev);
444 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
445 	struct sdhci_brcmstb_priv *priv = sdhci_pltfm_priv(pltfm_host);
446 
447 	clk_disable_unprepare(priv->base_clk);
448 	return sdhci_pltfm_suspend(dev);
449 }
450 
451 static int sdhci_brcmstb_resume(struct device *dev)
452 {
453 	struct sdhci_host *host = dev_get_drvdata(dev);
454 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
455 	struct sdhci_brcmstb_priv *priv = sdhci_pltfm_priv(pltfm_host);
456 	int ret;
457 
458 	ret = sdhci_pltfm_resume(dev);
459 	if (!ret && priv->base_freq_hz) {
460 		ret = clk_prepare_enable(priv->base_clk);
461 		/*
462 		 * Note: using clk_get_rate() below as clk_get_rate()
463 		 * honors CLK_GET_RATE_NOCACHE attribute, but clk_set_rate()
464 		 * may do implicit get_rate() calls that do not honor
465 		 * CLK_GET_RATE_NOCACHE.
466 		 */
467 		if (!ret &&
468 		    (clk_get_rate(priv->base_clk) != priv->base_freq_hz))
469 			ret = clk_set_rate(priv->base_clk, priv->base_freq_hz);
470 	}
471 
472 	return ret;
473 }
474 #endif
475 
476 static const struct dev_pm_ops sdhci_brcmstb_pmops = {
477 	SET_SYSTEM_SLEEP_PM_OPS(sdhci_brcmstb_suspend, sdhci_brcmstb_resume)
478 };
479 
480 static struct platform_driver sdhci_brcmstb_driver = {
481 	.driver		= {
482 		.name	= "sdhci-brcmstb",
483 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
484 		.pm	= &sdhci_brcmstb_pmops,
485 		.of_match_table = of_match_ptr(sdhci_brcm_of_match),
486 	},
487 	.probe		= sdhci_brcmstb_probe,
488 	.remove_new	= sdhci_pltfm_remove,
489 	.shutdown	= sdhci_brcmstb_shutdown,
490 };
491 
492 module_platform_driver(sdhci_brcmstb_driver);
493 
494 MODULE_DESCRIPTION("SDHCI driver for Broadcom BRCMSTB SoCs");
495 MODULE_AUTHOR("Broadcom");
496 MODULE_LICENSE("GPL v2");
497