xref: /openbmc/linux/drivers/mmc/host/sdhci-brcmstb.c (revision 27e45f2e)
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/mmc/host.h>
10 #include <linux/module.h>
11 #include <linux/of.h>
12 #include <linux/bitops.h>
13 #include <linux/delay.h>
14 
15 #include "sdhci-cqhci.h"
16 #include "sdhci-pltfm.h"
17 #include "cqhci.h"
18 
19 #define SDHCI_VENDOR 0x78
20 #define  SDHCI_VENDOR_ENHANCED_STRB 0x1
21 #define  SDHCI_VENDOR_GATE_SDCLK_EN 0x2
22 
23 #define BRCMSTB_MATCH_FLAGS_NO_64BIT		BIT(0)
24 #define BRCMSTB_MATCH_FLAGS_BROKEN_TIMEOUT	BIT(1)
25 #define BRCMSTB_MATCH_FLAGS_HAS_CLOCK_GATE	BIT(2)
26 
27 #define BRCMSTB_PRIV_FLAGS_HAS_CQE		BIT(0)
28 #define BRCMSTB_PRIV_FLAGS_GATE_CLOCK		BIT(1)
29 
30 #define SDHCI_ARASAN_CQE_BASE_ADDR		0x200
31 
32 struct sdhci_brcmstb_priv {
33 	void __iomem *cfg_regs;
34 	unsigned int flags;
35 	struct clk *base_clk;
36 	u32 base_freq_hz;
37 };
38 
39 struct brcmstb_match_priv {
40 	void (*hs400es)(struct mmc_host *mmc, struct mmc_ios *ios);
41 	struct sdhci_ops *ops;
42 	const unsigned int flags;
43 };
44 
45 static inline void enable_clock_gating(struct sdhci_host *host)
46 {
47 	u32 reg;
48 
49 	reg = sdhci_readl(host, SDHCI_VENDOR);
50 	reg |= SDHCI_VENDOR_GATE_SDCLK_EN;
51 	sdhci_writel(host, reg, SDHCI_VENDOR);
52 }
53 
54 static void brcmstb_reset(struct sdhci_host *host, u8 mask)
55 {
56 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
57 	struct sdhci_brcmstb_priv *priv = sdhci_pltfm_priv(pltfm_host);
58 
59 	sdhci_and_cqhci_reset(host, mask);
60 
61 	/* Reset will clear this, so re-enable it */
62 	if (priv->flags & BRCMSTB_PRIV_FLAGS_GATE_CLOCK)
63 		enable_clock_gating(host);
64 }
65 
66 static void sdhci_brcmstb_hs400es(struct mmc_host *mmc, struct mmc_ios *ios)
67 {
68 	struct sdhci_host *host = mmc_priv(mmc);
69 
70 	u32 reg;
71 
72 	dev_dbg(mmc_dev(mmc), "%s(): Setting HS400-Enhanced-Strobe mode\n",
73 		__func__);
74 	reg = readl(host->ioaddr + SDHCI_VENDOR);
75 	if (ios->enhanced_strobe)
76 		reg |= SDHCI_VENDOR_ENHANCED_STRB;
77 	else
78 		reg &= ~SDHCI_VENDOR_ENHANCED_STRB;
79 	writel(reg, host->ioaddr + SDHCI_VENDOR);
80 }
81 
82 static void sdhci_brcmstb_set_clock(struct sdhci_host *host, unsigned int clock)
83 {
84 	u16 clk;
85 
86 	host->mmc->actual_clock = 0;
87 
88 	clk = sdhci_calc_clk(host, clock, &host->mmc->actual_clock);
89 	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
90 
91 	if (clock == 0)
92 		return;
93 
94 	sdhci_enable_clk(host, clk);
95 }
96 
97 static void sdhci_brcmstb_set_uhs_signaling(struct sdhci_host *host,
98 					    unsigned int timing)
99 {
100 	u16 ctrl_2;
101 
102 	dev_dbg(mmc_dev(host->mmc), "%s: Setting UHS signaling for %d timing\n",
103 		__func__, timing);
104 	ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
105 	/* Select Bus Speed Mode for host */
106 	ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
107 	if ((timing == MMC_TIMING_MMC_HS200) ||
108 	    (timing == MMC_TIMING_UHS_SDR104))
109 		ctrl_2 |= SDHCI_CTRL_UHS_SDR104;
110 	else if (timing == MMC_TIMING_UHS_SDR12)
111 		ctrl_2 |= SDHCI_CTRL_UHS_SDR12;
112 	else if (timing == MMC_TIMING_SD_HS ||
113 		 timing == MMC_TIMING_MMC_HS ||
114 		 timing == MMC_TIMING_UHS_SDR25)
115 		ctrl_2 |= SDHCI_CTRL_UHS_SDR25;
116 	else if (timing == MMC_TIMING_UHS_SDR50)
117 		ctrl_2 |= SDHCI_CTRL_UHS_SDR50;
118 	else if ((timing == MMC_TIMING_UHS_DDR50) ||
119 		 (timing == MMC_TIMING_MMC_DDR52))
120 		ctrl_2 |= SDHCI_CTRL_UHS_DDR50;
121 	else if (timing == MMC_TIMING_MMC_HS400)
122 		ctrl_2 |= SDHCI_CTRL_HS400; /* Non-standard */
123 	sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
124 }
125 
126 static void sdhci_brcmstb_dumpregs(struct mmc_host *mmc)
127 {
128 	sdhci_dumpregs(mmc_priv(mmc));
129 }
130 
131 static void sdhci_brcmstb_cqe_enable(struct mmc_host *mmc)
132 {
133 	struct sdhci_host *host = mmc_priv(mmc);
134 	u32 reg;
135 
136 	reg = sdhci_readl(host, SDHCI_PRESENT_STATE);
137 	while (reg & SDHCI_DATA_AVAILABLE) {
138 		sdhci_readl(host, SDHCI_BUFFER);
139 		reg = sdhci_readl(host, SDHCI_PRESENT_STATE);
140 	}
141 
142 	sdhci_cqe_enable(mmc);
143 }
144 
145 static const struct cqhci_host_ops sdhci_brcmstb_cqhci_ops = {
146 	.enable         = sdhci_brcmstb_cqe_enable,
147 	.disable        = sdhci_cqe_disable,
148 	.dumpregs       = sdhci_brcmstb_dumpregs,
149 };
150 
151 static struct sdhci_ops sdhci_brcmstb_ops = {
152 	.set_clock = sdhci_set_clock,
153 	.set_bus_width = sdhci_set_bus_width,
154 	.reset = sdhci_reset,
155 	.set_uhs_signaling = sdhci_set_uhs_signaling,
156 };
157 
158 static struct sdhci_ops sdhci_brcmstb_ops_7216 = {
159 	.set_clock = sdhci_brcmstb_set_clock,
160 	.set_bus_width = sdhci_set_bus_width,
161 	.reset = brcmstb_reset,
162 	.set_uhs_signaling = sdhci_brcmstb_set_uhs_signaling,
163 };
164 
165 static struct brcmstb_match_priv match_priv_7425 = {
166 	.flags = BRCMSTB_MATCH_FLAGS_NO_64BIT |
167 	BRCMSTB_MATCH_FLAGS_BROKEN_TIMEOUT,
168 	.ops = &sdhci_brcmstb_ops,
169 };
170 
171 static struct brcmstb_match_priv match_priv_7445 = {
172 	.flags = BRCMSTB_MATCH_FLAGS_BROKEN_TIMEOUT,
173 	.ops = &sdhci_brcmstb_ops,
174 };
175 
176 static const struct brcmstb_match_priv match_priv_7216 = {
177 	.flags = BRCMSTB_MATCH_FLAGS_HAS_CLOCK_GATE,
178 	.hs400es = sdhci_brcmstb_hs400es,
179 	.ops = &sdhci_brcmstb_ops_7216,
180 };
181 
182 static const struct of_device_id __maybe_unused sdhci_brcm_of_match[] = {
183 	{ .compatible = "brcm,bcm7425-sdhci", .data = &match_priv_7425 },
184 	{ .compatible = "brcm,bcm7445-sdhci", .data = &match_priv_7445 },
185 	{ .compatible = "brcm,bcm7216-sdhci", .data = &match_priv_7216 },
186 	{},
187 };
188 
189 static u32 sdhci_brcmstb_cqhci_irq(struct sdhci_host *host, u32 intmask)
190 {
191 	int cmd_error = 0;
192 	int data_error = 0;
193 
194 	if (!sdhci_cqe_irq(host, intmask, &cmd_error, &data_error))
195 		return intmask;
196 
197 	cqhci_irq(host->mmc, intmask, cmd_error, data_error);
198 
199 	return 0;
200 }
201 
202 static int sdhci_brcmstb_add_host(struct sdhci_host *host,
203 				  struct sdhci_brcmstb_priv *priv)
204 {
205 	struct cqhci_host *cq_host;
206 	bool dma64;
207 	int ret;
208 
209 	if ((priv->flags & BRCMSTB_PRIV_FLAGS_HAS_CQE) == 0)
210 		return sdhci_add_host(host);
211 
212 	dev_dbg(mmc_dev(host->mmc), "CQE is enabled\n");
213 	host->mmc->caps2 |= MMC_CAP2_CQE | MMC_CAP2_CQE_DCMD;
214 	ret = sdhci_setup_host(host);
215 	if (ret)
216 		return ret;
217 
218 	cq_host = devm_kzalloc(mmc_dev(host->mmc),
219 			       sizeof(*cq_host), GFP_KERNEL);
220 	if (!cq_host) {
221 		ret = -ENOMEM;
222 		goto cleanup;
223 	}
224 
225 	cq_host->mmio = host->ioaddr + SDHCI_ARASAN_CQE_BASE_ADDR;
226 	cq_host->ops = &sdhci_brcmstb_cqhci_ops;
227 
228 	dma64 = host->flags & SDHCI_USE_64_BIT_DMA;
229 	if (dma64) {
230 		dev_dbg(mmc_dev(host->mmc), "Using 64 bit DMA\n");
231 		cq_host->caps |= CQHCI_TASK_DESC_SZ_128;
232 	}
233 
234 	ret = cqhci_init(cq_host, host->mmc, dma64);
235 	if (ret)
236 		goto cleanup;
237 
238 	ret = __sdhci_add_host(host);
239 	if (ret)
240 		goto cleanup;
241 
242 	return 0;
243 
244 cleanup:
245 	sdhci_cleanup_host(host);
246 	return ret;
247 }
248 
249 static int sdhci_brcmstb_probe(struct platform_device *pdev)
250 {
251 	const struct brcmstb_match_priv *match_priv;
252 	struct sdhci_pltfm_data brcmstb_pdata;
253 	struct sdhci_pltfm_host *pltfm_host;
254 	const struct of_device_id *match;
255 	struct sdhci_brcmstb_priv *priv;
256 	u32 actual_clock_mhz;
257 	struct sdhci_host *host;
258 	struct resource *iomem;
259 	struct clk *clk;
260 	struct clk *base_clk = NULL;
261 	int res;
262 
263 	match = of_match_node(sdhci_brcm_of_match, pdev->dev.of_node);
264 	match_priv = match->data;
265 
266 	dev_dbg(&pdev->dev, "Probe found match for %s\n",  match->compatible);
267 
268 	clk = devm_clk_get_optional(&pdev->dev, NULL);
269 	if (IS_ERR(clk))
270 		return dev_err_probe(&pdev->dev, PTR_ERR(clk),
271 				     "Failed to get clock from Device Tree\n");
272 
273 	res = clk_prepare_enable(clk);
274 	if (res)
275 		return res;
276 
277 	memset(&brcmstb_pdata, 0, sizeof(brcmstb_pdata));
278 	brcmstb_pdata.ops = match_priv->ops;
279 	host = sdhci_pltfm_init(pdev, &brcmstb_pdata,
280 				sizeof(struct sdhci_brcmstb_priv));
281 	if (IS_ERR(host)) {
282 		res = PTR_ERR(host);
283 		goto err_clk;
284 	}
285 
286 	pltfm_host = sdhci_priv(host);
287 	priv = sdhci_pltfm_priv(pltfm_host);
288 	if (device_property_read_bool(&pdev->dev, "supports-cqe")) {
289 		priv->flags |= BRCMSTB_PRIV_FLAGS_HAS_CQE;
290 		match_priv->ops->irq = sdhci_brcmstb_cqhci_irq;
291 	}
292 
293 	/* Map in the non-standard CFG registers */
294 	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
295 	priv->cfg_regs = devm_ioremap_resource(&pdev->dev, iomem);
296 	if (IS_ERR(priv->cfg_regs)) {
297 		res = PTR_ERR(priv->cfg_regs);
298 		goto err;
299 	}
300 
301 	sdhci_get_of_property(pdev);
302 	res = mmc_of_parse(host->mmc);
303 	if (res)
304 		goto err;
305 
306 	/*
307 	 * Automatic clock gating does not work for SD cards that may
308 	 * voltage switch so only enable it for non-removable devices.
309 	 */
310 	if ((match_priv->flags & BRCMSTB_MATCH_FLAGS_HAS_CLOCK_GATE) &&
311 	    (host->mmc->caps & MMC_CAP_NONREMOVABLE))
312 		priv->flags |= BRCMSTB_PRIV_FLAGS_GATE_CLOCK;
313 
314 	/*
315 	 * If the chip has enhanced strobe and it's enabled, add
316 	 * callback
317 	 */
318 	if (match_priv->hs400es &&
319 	    (host->mmc->caps2 & MMC_CAP2_HS400_ES))
320 		host->mmc_host_ops.hs400_enhanced_strobe = match_priv->hs400es;
321 
322 	/*
323 	 * Supply the existing CAPS, but clear the UHS modes. This
324 	 * will allow these modes to be specified by device tree
325 	 * properties through mmc_of_parse().
326 	 */
327 	host->caps = sdhci_readl(host, SDHCI_CAPABILITIES);
328 	if (match_priv->flags & BRCMSTB_MATCH_FLAGS_NO_64BIT)
329 		host->caps &= ~SDHCI_CAN_64BIT;
330 	host->caps1 = sdhci_readl(host, SDHCI_CAPABILITIES_1);
331 	host->caps1 &= ~(SDHCI_SUPPORT_SDR50 | SDHCI_SUPPORT_SDR104 |
332 			 SDHCI_SUPPORT_DDR50);
333 	host->quirks |= SDHCI_QUIRK_MISSING_CAPS;
334 
335 	if (match_priv->flags & BRCMSTB_MATCH_FLAGS_BROKEN_TIMEOUT)
336 		host->quirks |= SDHCI_QUIRK_BROKEN_TIMEOUT_VAL;
337 
338 	/* Change the base clock frequency if the DT property exists */
339 	if (device_property_read_u32(&pdev->dev, "clock-frequency",
340 				     &priv->base_freq_hz) != 0)
341 		goto add_host;
342 
343 	base_clk = devm_clk_get_optional(&pdev->dev, "sdio_freq");
344 	if (IS_ERR(base_clk)) {
345 		dev_warn(&pdev->dev, "Clock for \"sdio_freq\" not found\n");
346 		goto add_host;
347 	}
348 
349 	res = clk_prepare_enable(base_clk);
350 	if (res)
351 		goto err;
352 
353 	/* set improved clock rate */
354 	clk_set_rate(base_clk, priv->base_freq_hz);
355 	actual_clock_mhz = clk_get_rate(base_clk) / 1000000;
356 
357 	host->caps &= ~SDHCI_CLOCK_V3_BASE_MASK;
358 	host->caps |= (actual_clock_mhz << SDHCI_CLOCK_BASE_SHIFT);
359 	/* Disable presets because they are now incorrect */
360 	host->quirks2 |= SDHCI_QUIRK2_PRESET_VALUE_BROKEN;
361 
362 	dev_dbg(&pdev->dev, "Base Clock Frequency changed to %dMHz\n",
363 		actual_clock_mhz);
364 	priv->base_clk = base_clk;
365 
366 add_host:
367 	res = sdhci_brcmstb_add_host(host, priv);
368 	if (res)
369 		goto err;
370 
371 	pltfm_host->clk = clk;
372 	return res;
373 
374 err:
375 	sdhci_pltfm_free(pdev);
376 err_clk:
377 	clk_disable_unprepare(base_clk);
378 	clk_disable_unprepare(clk);
379 	return res;
380 }
381 
382 static void sdhci_brcmstb_shutdown(struct platform_device *pdev)
383 {
384 	sdhci_pltfm_suspend(&pdev->dev);
385 }
386 
387 MODULE_DEVICE_TABLE(of, sdhci_brcm_of_match);
388 
389 #ifdef CONFIG_PM_SLEEP
390 static int sdhci_brcmstb_suspend(struct device *dev)
391 {
392 	struct sdhci_host *host = dev_get_drvdata(dev);
393 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
394 	struct sdhci_brcmstb_priv *priv = sdhci_pltfm_priv(pltfm_host);
395 
396 	clk_disable_unprepare(priv->base_clk);
397 	return sdhci_pltfm_suspend(dev);
398 }
399 
400 static int sdhci_brcmstb_resume(struct device *dev)
401 {
402 	struct sdhci_host *host = dev_get_drvdata(dev);
403 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
404 	struct sdhci_brcmstb_priv *priv = sdhci_pltfm_priv(pltfm_host);
405 	int ret;
406 
407 	ret = sdhci_pltfm_resume(dev);
408 	if (!ret && priv->base_freq_hz) {
409 		ret = clk_prepare_enable(priv->base_clk);
410 		/*
411 		 * Note: using clk_get_rate() below as clk_get_rate()
412 		 * honors CLK_GET_RATE_NOCACHE attribute, but clk_set_rate()
413 		 * may do implicit get_rate() calls that do not honor
414 		 * CLK_GET_RATE_NOCACHE.
415 		 */
416 		if (!ret &&
417 		    (clk_get_rate(priv->base_clk) != priv->base_freq_hz))
418 			ret = clk_set_rate(priv->base_clk, priv->base_freq_hz);
419 	}
420 
421 	return ret;
422 }
423 #endif
424 
425 static const struct dev_pm_ops sdhci_brcmstb_pmops = {
426 	SET_SYSTEM_SLEEP_PM_OPS(sdhci_brcmstb_suspend, sdhci_brcmstb_resume)
427 };
428 
429 static struct platform_driver sdhci_brcmstb_driver = {
430 	.driver		= {
431 		.name	= "sdhci-brcmstb",
432 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
433 		.pm	= &sdhci_brcmstb_pmops,
434 		.of_match_table = of_match_ptr(sdhci_brcm_of_match),
435 	},
436 	.probe		= sdhci_brcmstb_probe,
437 	.remove		= sdhci_pltfm_unregister,
438 	.shutdown	= sdhci_brcmstb_shutdown,
439 };
440 
441 module_platform_driver(sdhci_brcmstb_driver);
442 
443 MODULE_DESCRIPTION("SDHCI driver for Broadcom BRCMSTB SoCs");
444 MODULE_AUTHOR("Broadcom");
445 MODULE_LICENSE("GPL v2");
446