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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Atmel SDMMC controller driver.4 *5 * Copyright (C) 2015 Atmel,6 *		 2015 Ludovic Desroches <ludovic.desroches@atmel.com>7 */8 9#include <linux/bitfield.h>10#include <linux/clk.h>11#include <linux/delay.h>12#include <linux/err.h>13#include <linux/io.h>14#include <linux/iopoll.h>15#include <linux/kernel.h>16#include <linux/mmc/host.h>17#include <linux/mmc/slot-gpio.h>18#include <linux/module.h>19#include <linux/of.h>20#include <linux/platform_device.h>21#include <linux/pm.h>22#include <linux/pm_runtime.h>23 24#include "sdhci-pltfm.h"25 26#define SDMMC_MC1R	0x20427#define		SDMMC_MC1R_DDR		BIT(3)28#define		SDMMC_MC1R_FCD		BIT(7)29#define SDMMC_CACR	0x23030#define		SDMMC_CACR_CAPWREN	BIT(0)31#define		SDMMC_CACR_KEY		(0x46 << 8)32#define SDMMC_CALCR	0x24033#define		SDMMC_CALCR_EN		BIT(0)34#define		SDMMC_CALCR_ALWYSON	BIT(4)35 36#define SDHCI_AT91_PRESET_COMMON_CONF	0x400 /* drv type B, programmable clock mode */37 38struct sdhci_at91_soc_data {39	const struct sdhci_pltfm_data *pdata;40	bool baseclk_is_generated_internally;41	unsigned int divider_for_baseclk;42};43 44struct sdhci_at91_priv {45	const struct sdhci_at91_soc_data *soc_data;46	struct clk *hclock;47	struct clk *gck;48	struct clk *mainck;49	bool restore_needed;50	bool cal_always_on;51};52 53static void sdhci_at91_set_force_card_detect(struct sdhci_host *host)54{55	u8 mc1r;56 57	mc1r = readb(host->ioaddr + SDMMC_MC1R);58	mc1r |= SDMMC_MC1R_FCD;59	writeb(mc1r, host->ioaddr + SDMMC_MC1R);60}61 62static void sdhci_at91_set_clock(struct sdhci_host *host, unsigned int clock)63{64	u16 clk;65 66	host->mmc->actual_clock = 0;67 68	/*69	 * There is no requirement to disable the internal clock before70	 * changing the SD clock configuration. Moreover, disabling the71	 * internal clock, changing the configuration and re-enabling the72	 * internal clock causes some bugs. It can prevent to get the internal73	 * clock stable flag ready and an unexpected switch to the base clock74	 * when using presets.75	 */76	clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);77	clk &= SDHCI_CLOCK_INT_EN;78	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);79 80	if (clock == 0)81		return;82 83	clk = sdhci_calc_clk(host, clock, &host->mmc->actual_clock);84 85	clk |= SDHCI_CLOCK_INT_EN;86	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);87 88	/* Wait max 20 ms */89	if (read_poll_timeout(sdhci_readw, clk, (clk & SDHCI_CLOCK_INT_STABLE),90			      1000, 20000, false, host, SDHCI_CLOCK_CONTROL)) {91		pr_err("%s: Internal clock never stabilised.\n",92		       mmc_hostname(host->mmc));93		return;94	}95 96	clk |= SDHCI_CLOCK_CARD_EN;97	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);98}99 100static void sdhci_at91_set_uhs_signaling(struct sdhci_host *host,101					 unsigned int timing)102{103	u8 mc1r;104 105	if (timing == MMC_TIMING_MMC_DDR52) {106		mc1r = sdhci_readb(host, SDMMC_MC1R);107		mc1r |= SDMMC_MC1R_DDR;108		sdhci_writeb(host, mc1r, SDMMC_MC1R);109	}110	sdhci_set_uhs_signaling(host, timing);111}112 113static void sdhci_at91_reset(struct sdhci_host *host, u8 mask)114{115	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);116	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);117	unsigned int tmp;118 119	sdhci_reset(host, mask);120 121	if ((host->mmc->caps & MMC_CAP_NONREMOVABLE)122	    || mmc_gpio_get_cd(host->mmc) >= 0)123		sdhci_at91_set_force_card_detect(host);124 125	if (priv->cal_always_on && (mask & SDHCI_RESET_ALL)) {126		u32 calcr = sdhci_readl(host, SDMMC_CALCR);127 128		sdhci_writel(host, calcr | SDMMC_CALCR_ALWYSON | SDMMC_CALCR_EN,129			     SDMMC_CALCR);130 131		if (read_poll_timeout(sdhci_readl, tmp, !(tmp & SDMMC_CALCR_EN),132				      10, 20000, false, host, SDMMC_CALCR))133			dev_err(mmc_dev(host->mmc), "Failed to calibrate\n");134	}135}136 137static const struct sdhci_ops sdhci_at91_sama5d2_ops = {138	.set_clock		= sdhci_at91_set_clock,139	.set_bus_width		= sdhci_set_bus_width,140	.reset			= sdhci_at91_reset,141	.set_uhs_signaling	= sdhci_at91_set_uhs_signaling,142	.set_power		= sdhci_set_power_and_bus_voltage,143};144 145static const struct sdhci_pltfm_data sdhci_sama5d2_pdata = {146	.ops = &sdhci_at91_sama5d2_ops,147};148 149static const struct sdhci_at91_soc_data soc_data_sama5d2 = {150	.pdata = &sdhci_sama5d2_pdata,151	.baseclk_is_generated_internally = false,152};153 154static const struct sdhci_at91_soc_data soc_data_sam9x60 = {155	.pdata = &sdhci_sama5d2_pdata,156	.baseclk_is_generated_internally = true,157	.divider_for_baseclk = 2,158};159 160static const struct of_device_id sdhci_at91_dt_match[] = {161	{ .compatible = "atmel,sama5d2-sdhci", .data = &soc_data_sama5d2 },162	{ .compatible = "microchip,sam9x60-sdhci", .data = &soc_data_sam9x60 },163	{}164};165MODULE_DEVICE_TABLE(of, sdhci_at91_dt_match);166 167static int sdhci_at91_set_clks_presets(struct device *dev)168{169	struct sdhci_host *host = dev_get_drvdata(dev);170	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);171	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);172	unsigned int			caps0, caps1;173	unsigned int			clk_base, clk_mul;174	unsigned int			gck_rate, clk_base_rate;175	unsigned int			preset_div;176 177	clk_prepare_enable(priv->hclock);178	caps0 = readl(host->ioaddr + SDHCI_CAPABILITIES);179	caps1 = readl(host->ioaddr + SDHCI_CAPABILITIES_1);180 181	gck_rate = clk_get_rate(priv->gck);182	if (priv->soc_data->baseclk_is_generated_internally)183		clk_base_rate = gck_rate / priv->soc_data->divider_for_baseclk;184	else185		clk_base_rate = clk_get_rate(priv->mainck);186 187	clk_base = clk_base_rate / 1000000;188	clk_mul = gck_rate / clk_base_rate - 1;189 190	caps0 &= ~SDHCI_CLOCK_V3_BASE_MASK;191	caps0 |= FIELD_PREP(SDHCI_CLOCK_V3_BASE_MASK, clk_base);192	caps1 &= ~SDHCI_CLOCK_MUL_MASK;193	caps1 |= FIELD_PREP(SDHCI_CLOCK_MUL_MASK, clk_mul);194	/* Set capabilities in r/w mode. */195	writel(SDMMC_CACR_KEY | SDMMC_CACR_CAPWREN, host->ioaddr + SDMMC_CACR);196	writel(caps0, host->ioaddr + SDHCI_CAPABILITIES);197	writel(caps1, host->ioaddr + SDHCI_CAPABILITIES_1);198	/* Set capabilities in ro mode. */199	writel(0, host->ioaddr + SDMMC_CACR);200 201	dev_dbg(dev, "update clk mul to %u as gck rate is %u Hz and clk base is %u Hz\n",202		clk_mul, gck_rate, clk_base_rate);203 204	/*205	 * We have to set preset values because it depends on the clk_mul206	 * value. Moreover, SDR104 is supported in a degraded mode since the207	 * maximum sd clock value is 120 MHz instead of 208 MHz. For that208	 * reason, we need to use presets to support SDR104.209	 */210	preset_div = DIV_ROUND_UP(gck_rate, 24000000) - 1;211	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,212	       host->ioaddr + SDHCI_PRESET_FOR_SDR12);213	preset_div = DIV_ROUND_UP(gck_rate, 50000000) - 1;214	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,215	       host->ioaddr + SDHCI_PRESET_FOR_SDR25);216	preset_div = DIV_ROUND_UP(gck_rate, 100000000) - 1;217	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,218	       host->ioaddr + SDHCI_PRESET_FOR_SDR50);219	preset_div = DIV_ROUND_UP(gck_rate, 120000000) - 1;220	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,221	       host->ioaddr + SDHCI_PRESET_FOR_SDR104);222	preset_div = DIV_ROUND_UP(gck_rate, 50000000) - 1;223	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,224	       host->ioaddr + SDHCI_PRESET_FOR_DDR50);225 226	clk_prepare_enable(priv->mainck);227	clk_prepare_enable(priv->gck);228 229	return 0;230}231 232#ifdef CONFIG_PM_SLEEP233static int sdhci_at91_suspend(struct device *dev)234{235	struct sdhci_host *host = dev_get_drvdata(dev);236	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);237	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);238	int ret;239 240	ret = pm_runtime_force_suspend(dev);241 242	priv->restore_needed = true;243 244	return ret;245}246#endif /* CONFIG_PM_SLEEP */247 248#ifdef CONFIG_PM249static int sdhci_at91_runtime_suspend(struct device *dev)250{251	struct sdhci_host *host = dev_get_drvdata(dev);252	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);253	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);254	int ret;255 256	ret = sdhci_runtime_suspend_host(host);257 258	if (host->tuning_mode != SDHCI_TUNING_MODE_3)259		mmc_retune_needed(host->mmc);260 261	clk_disable_unprepare(priv->gck);262	clk_disable_unprepare(priv->hclock);263	clk_disable_unprepare(priv->mainck);264 265	return ret;266}267 268static int sdhci_at91_runtime_resume(struct device *dev)269{270	struct sdhci_host *host = dev_get_drvdata(dev);271	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);272	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);273	int ret;274 275	if (priv->restore_needed) {276		ret = sdhci_at91_set_clks_presets(dev);277		if (ret)278			return ret;279 280		priv->restore_needed = false;281		goto out;282	}283 284	ret = clk_prepare_enable(priv->mainck);285	if (ret) {286		dev_err(dev, "can't enable mainck\n");287		return ret;288	}289 290	ret = clk_prepare_enable(priv->hclock);291	if (ret) {292		dev_err(dev, "can't enable hclock\n");293		return ret;294	}295 296	ret = clk_prepare_enable(priv->gck);297	if (ret) {298		dev_err(dev, "can't enable gck\n");299		return ret;300	}301 302out:303	return sdhci_runtime_resume_host(host, 0);304}305#endif /* CONFIG_PM */306 307static const struct dev_pm_ops sdhci_at91_dev_pm_ops = {308	SET_SYSTEM_SLEEP_PM_OPS(sdhci_at91_suspend, pm_runtime_force_resume)309	SET_RUNTIME_PM_OPS(sdhci_at91_runtime_suspend,310			   sdhci_at91_runtime_resume,311			   NULL)312};313 314static int sdhci_at91_probe(struct platform_device *pdev)315{316	const struct sdhci_at91_soc_data	*soc_data;317	struct sdhci_host		*host;318	struct sdhci_pltfm_host		*pltfm_host;319	struct sdhci_at91_priv		*priv;320	int				ret;321 322	soc_data = of_device_get_match_data(&pdev->dev);323	if (!soc_data)324		return -EINVAL;325 326	host = sdhci_pltfm_init(pdev, soc_data->pdata, sizeof(*priv));327	if (IS_ERR(host))328		return PTR_ERR(host);329 330	pltfm_host = sdhci_priv(host);331	priv = sdhci_pltfm_priv(pltfm_host);332	priv->soc_data = soc_data;333 334	priv->mainck = devm_clk_get(&pdev->dev, "baseclk");335	if (IS_ERR(priv->mainck)) {336		if (soc_data->baseclk_is_generated_internally) {337			priv->mainck = NULL;338		} else {339			dev_err(&pdev->dev, "failed to get baseclk\n");340			ret = PTR_ERR(priv->mainck);341			goto sdhci_pltfm_free;342		}343	}344 345	priv->hclock = devm_clk_get(&pdev->dev, "hclock");346	if (IS_ERR(priv->hclock)) {347		dev_err(&pdev->dev, "failed to get hclock\n");348		ret = PTR_ERR(priv->hclock);349		goto sdhci_pltfm_free;350	}351 352	priv->gck = devm_clk_get(&pdev->dev, "multclk");353	if (IS_ERR(priv->gck)) {354		dev_err(&pdev->dev, "failed to get multclk\n");355		ret = PTR_ERR(priv->gck);356		goto sdhci_pltfm_free;357	}358 359	ret = sdhci_at91_set_clks_presets(&pdev->dev);360	if (ret)361		goto sdhci_pltfm_free;362 363	priv->restore_needed = false;364 365	/*366	 * if SDCAL pin is wrongly connected, we must enable367	 * the analog calibration cell permanently.368	 */369	priv->cal_always_on =370		device_property_read_bool(&pdev->dev,371					  "microchip,sdcal-inverted");372 373	ret = mmc_of_parse(host->mmc);374	if (ret)375		goto clocks_disable_unprepare;376 377	sdhci_get_of_property(pdev);378 379	pm_runtime_get_noresume(&pdev->dev);380	pm_runtime_set_active(&pdev->dev);381	pm_runtime_enable(&pdev->dev);382	pm_runtime_set_autosuspend_delay(&pdev->dev, 50);383	pm_runtime_use_autosuspend(&pdev->dev);384 385	/* HS200 is broken at this moment */386	host->quirks2 |= SDHCI_QUIRK2_BROKEN_HS200;387 388	ret = sdhci_add_host(host);389	if (ret)390		goto pm_runtime_disable;391 392	/*393	 * When calling sdhci_runtime_suspend_host(), the sdhci layer makes394	 * the assumption that all the clocks of the controller are disabled.395	 * It means we can't get irq from it when it is runtime suspended.396	 * For that reason, it is not planned to wake-up on a card detect irq397	 * from the controller.398	 * If we want to use runtime PM and to be able to wake-up on card399	 * insertion, we have to use a GPIO for the card detection or we can400	 * use polling. Be aware that using polling will resume/suspend the401	 * controller between each attempt.402	 * Disable SDHCI_QUIRK_BROKEN_CARD_DETECTION to be sure nobody tries403	 * to enable polling via device tree with broken-cd property.404	 */405	if (mmc_card_is_removable(host->mmc) &&406	    mmc_gpio_get_cd(host->mmc) < 0) {407		host->mmc->caps |= MMC_CAP_NEEDS_POLL;408		host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION;409	}410 411	/*412	 * If the device attached to the MMC bus is not removable, it is safer413	 * to set the Force Card Detect bit. People often don't connect the414	 * card detect signal and use this pin for another purpose. If the card415	 * detect pin is not muxed to SDHCI controller, a default value is416	 * used. This value can be different from a SoC revision to another417	 * one. Problems come when this default value is not card present. To418	 * avoid this case, if the device is non removable then the card419	 * detection procedure using the SDMCC_CD signal is bypassed.420	 * This bit is reset when a software reset for all command is performed421	 * so we need to implement our own reset function to set back this bit.422	 *423	 * WA: SAMA5D2 doesn't drive CMD if using CD GPIO line.424	 */425	if ((host->mmc->caps & MMC_CAP_NONREMOVABLE)426	    || mmc_gpio_get_cd(host->mmc) >= 0)427		sdhci_at91_set_force_card_detect(host);428 429	pm_runtime_put_autosuspend(&pdev->dev);430 431	return 0;432 433pm_runtime_disable:434	pm_runtime_disable(&pdev->dev);435	pm_runtime_set_suspended(&pdev->dev);436	pm_runtime_put_noidle(&pdev->dev);437clocks_disable_unprepare:438	clk_disable_unprepare(priv->gck);439	clk_disable_unprepare(priv->mainck);440	clk_disable_unprepare(priv->hclock);441sdhci_pltfm_free:442	sdhci_pltfm_free(pdev);443	return ret;444}445 446static void sdhci_at91_remove(struct platform_device *pdev)447{448	struct sdhci_host	*host = platform_get_drvdata(pdev);449	struct sdhci_pltfm_host	*pltfm_host = sdhci_priv(host);450	struct sdhci_at91_priv	*priv = sdhci_pltfm_priv(pltfm_host);451	struct clk *gck = priv->gck;452	struct clk *hclock = priv->hclock;453	struct clk *mainck = priv->mainck;454 455	pm_runtime_get_sync(&pdev->dev);456	pm_runtime_disable(&pdev->dev);457	pm_runtime_put_noidle(&pdev->dev);458 459	sdhci_pltfm_remove(pdev);460 461	clk_disable_unprepare(gck);462	clk_disable_unprepare(hclock);463	clk_disable_unprepare(mainck);464}465 466static struct platform_driver sdhci_at91_driver = {467	.driver		= {468		.name	= "sdhci-at91",469		.probe_type = PROBE_PREFER_ASYNCHRONOUS,470		.of_match_table = sdhci_at91_dt_match,471		.pm	= &sdhci_at91_dev_pm_ops,472	},473	.probe		= sdhci_at91_probe,474	.remove_new	= sdhci_at91_remove,475};476 477module_platform_driver(sdhci_at91_driver);478 479MODULE_DESCRIPTION("SDHCI driver for at91");480MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@atmel.com>");481MODULE_LICENSE("GPL v2");482