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
32struct sdhci_brcmstb_priv {
33	void __iomem *cfg_regs;
34	unsigned int flags;
35	struct clk *base_clk;
36	u32 base_freq_hz;
37};
38
39struct 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
45static 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
54static 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
66static 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
82static 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
97static 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
126static void sdhci_brcmstb_dumpregs(struct mmc_host *mmc)
127{
128	sdhci_dumpregs(mmc_priv(mmc));
129}
130
131static 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
145static 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
151static 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
158static 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
165static 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
171static struct brcmstb_match_priv match_priv_7445 = {
172	.flags = BRCMSTB_MATCH_FLAGS_BROKEN_TIMEOUT,
173	.ops = &sdhci_brcmstb_ops,
174};
175
176static 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
182static 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
189static 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
202static 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
244cleanup:
245	sdhci_cleanup_host(host);
246	return ret;
247}
248
249static 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 clk *clk;
259	struct clk *base_clk = NULL;
260	int res;
261
262	match = of_match_node(sdhci_brcm_of_match, pdev->dev.of_node);
263	match_priv = match->data;
264
265	dev_dbg(&pdev->dev, "Probe found match for %s\n",  match->compatible);
266
267	clk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
268	if (IS_ERR(clk))
269		return dev_err_probe(&pdev->dev, PTR_ERR(clk),
270				     "Failed to get and enable clock from Device Tree\n");
271
272	memset(&brcmstb_pdata, 0, sizeof(brcmstb_pdata));
273	brcmstb_pdata.ops = match_priv->ops;
274	host = sdhci_pltfm_init(pdev, &brcmstb_pdata,
275				sizeof(struct sdhci_brcmstb_priv));
276	if (IS_ERR(host))
277		return PTR_ERR(host);
278
279	pltfm_host = sdhci_priv(host);
280	priv = sdhci_pltfm_priv(pltfm_host);
281	if (device_property_read_bool(&pdev->dev, "supports-cqe")) {
282		priv->flags |= BRCMSTB_PRIV_FLAGS_HAS_CQE;
283		match_priv->ops->irq = sdhci_brcmstb_cqhci_irq;
284	}
285
286	/* Map in the non-standard CFG registers */
287	priv->cfg_regs = devm_platform_get_and_ioremap_resource(pdev, 1, NULL);
288	if (IS_ERR(priv->cfg_regs)) {
289		res = PTR_ERR(priv->cfg_regs);
290		goto err;
291	}
292
293	sdhci_get_of_property(pdev);
294	res = mmc_of_parse(host->mmc);
295	if (res)
296		goto err;
297
298	/*
299	 * Automatic clock gating does not work for SD cards that may
300	 * voltage switch so only enable it for non-removable devices.
301	 */
302	if ((match_priv->flags & BRCMSTB_MATCH_FLAGS_HAS_CLOCK_GATE) &&
303	    (host->mmc->caps & MMC_CAP_NONREMOVABLE))
304		priv->flags |= BRCMSTB_PRIV_FLAGS_GATE_CLOCK;
305
306	/*
307	 * If the chip has enhanced strobe and it's enabled, add
308	 * callback
309	 */
310	if (match_priv->hs400es &&
311	    (host->mmc->caps2 & MMC_CAP2_HS400_ES))
312		host->mmc_host_ops.hs400_enhanced_strobe = match_priv->hs400es;
313
314	/*
315	 * Supply the existing CAPS, but clear the UHS modes. This
316	 * will allow these modes to be specified by device tree
317	 * properties through mmc_of_parse().
318	 */
319	sdhci_read_caps(host);
320	if (match_priv->flags & BRCMSTB_MATCH_FLAGS_NO_64BIT)
321		host->caps &= ~SDHCI_CAN_64BIT;
322	host->caps1 &= ~(SDHCI_SUPPORT_SDR50 | SDHCI_SUPPORT_SDR104 |
323			 SDHCI_SUPPORT_DDR50);
324
325	if (match_priv->flags & BRCMSTB_MATCH_FLAGS_BROKEN_TIMEOUT)
326		host->quirks |= SDHCI_QUIRK_BROKEN_TIMEOUT_VAL;
327
328	/* Change the base clock frequency if the DT property exists */
329	if (device_property_read_u32(&pdev->dev, "clock-frequency",
330				     &priv->base_freq_hz) != 0)
331		goto add_host;
332
333	base_clk = devm_clk_get_optional(&pdev->dev, "sdio_freq");
334	if (IS_ERR(base_clk)) {
335		dev_warn(&pdev->dev, "Clock for \"sdio_freq\" not found\n");
336		goto add_host;
337	}
338
339	res = clk_prepare_enable(base_clk);
340	if (res)
341		goto err;
342
343	/* set improved clock rate */
344	clk_set_rate(base_clk, priv->base_freq_hz);
345	actual_clock_mhz = clk_get_rate(base_clk) / 1000000;
346
347	host->caps &= ~SDHCI_CLOCK_V3_BASE_MASK;
348	host->caps |= (actual_clock_mhz << SDHCI_CLOCK_BASE_SHIFT);
349	/* Disable presets because they are now incorrect */
350	host->quirks2 |= SDHCI_QUIRK2_PRESET_VALUE_BROKEN;
351
352	dev_dbg(&pdev->dev, "Base Clock Frequency changed to %dMHz\n",
353		actual_clock_mhz);
354	priv->base_clk = base_clk;
355
356add_host:
357	res = sdhci_brcmstb_add_host(host, priv);
358	if (res)
359		goto err;
360
361	pltfm_host->clk = clk;
362	return res;
363
364err:
365	sdhci_pltfm_free(pdev);
366	clk_disable_unprepare(base_clk);
367	return res;
368}
369
370static void sdhci_brcmstb_shutdown(struct platform_device *pdev)
371{
372	sdhci_pltfm_suspend(&pdev->dev);
373}
374
375MODULE_DEVICE_TABLE(of, sdhci_brcm_of_match);
376
377#ifdef CONFIG_PM_SLEEP
378static int sdhci_brcmstb_suspend(struct device *dev)
379{
380	struct sdhci_host *host = dev_get_drvdata(dev);
381	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
382	struct sdhci_brcmstb_priv *priv = sdhci_pltfm_priv(pltfm_host);
383
384	clk_disable_unprepare(priv->base_clk);
385	return sdhci_pltfm_suspend(dev);
386}
387
388static int sdhci_brcmstb_resume(struct device *dev)
389{
390	struct sdhci_host *host = dev_get_drvdata(dev);
391	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
392	struct sdhci_brcmstb_priv *priv = sdhci_pltfm_priv(pltfm_host);
393	int ret;
394
395	ret = sdhci_pltfm_resume(dev);
396	if (!ret && priv->base_freq_hz) {
397		ret = clk_prepare_enable(priv->base_clk);
398		/*
399		 * Note: using clk_get_rate() below as clk_get_rate()
400		 * honors CLK_GET_RATE_NOCACHE attribute, but clk_set_rate()
401		 * may do implicit get_rate() calls that do not honor
402		 * CLK_GET_RATE_NOCACHE.
403		 */
404		if (!ret &&
405		    (clk_get_rate(priv->base_clk) != priv->base_freq_hz))
406			ret = clk_set_rate(priv->base_clk, priv->base_freq_hz);
407	}
408
409	return ret;
410}
411#endif
412
413static const struct dev_pm_ops sdhci_brcmstb_pmops = {
414	SET_SYSTEM_SLEEP_PM_OPS(sdhci_brcmstb_suspend, sdhci_brcmstb_resume)
415};
416
417static struct platform_driver sdhci_brcmstb_driver = {
418	.driver		= {
419		.name	= "sdhci-brcmstb",
420		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
421		.pm	= &sdhci_brcmstb_pmops,
422		.of_match_table = of_match_ptr(sdhci_brcm_of_match),
423	},
424	.probe		= sdhci_brcmstb_probe,
425	.remove_new	= sdhci_pltfm_remove,
426	.shutdown	= sdhci_brcmstb_shutdown,
427};
428
429module_platform_driver(sdhci_brcmstb_driver);
430
431MODULE_DESCRIPTION("SDHCI driver for Broadcom BRCMSTB SoCs");
432MODULE_AUTHOR("Broadcom");
433MODULE_LICENSE("GPL v2");
434