[deliverable/linux.git] / drivers / mmc / host / sdhci-iproc.c

/*
 * Copyright (C) 2014 Broadcom Corporation
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

/*
 * iProc SDHCI platform driver
 */

#include <linux/delay.h>
#include <linux/module.h>
#include <linux/mmc/host.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include "sdhci-pltfm.h"

struct sdhci_iproc_data {
	const struct sdhci_pltfm_data *pdata;
	u32 caps;
	u32 caps1;
	u32 mmc_caps;
};

struct sdhci_iproc_host {
	const struct sdhci_iproc_data *data;
	u32 shadow_cmd;
	u32 shadow_blk;
};

#define REG_OFFSET_IN_BITS(reg) ((reg) << 3 & 0x18)

static inline u32 sdhci_iproc_readl(struct sdhci_host *host, int reg)
{
	u32 val = readl(host->ioaddr + reg);

	pr_debug("%s: readl [0x%02x] 0x%08x\n",
		 mmc_hostname(host->mmc), reg, val);
	return val;
}

static u16 sdhci_iproc_readw(struct sdhci_host *host, int reg)
{
	u32 val = sdhci_iproc_readl(host, (reg & ~3));
	u16 word = val >> REG_OFFSET_IN_BITS(reg) & 0xffff;
	return word;
}

static u8 sdhci_iproc_readb(struct sdhci_host *host, int reg)
{
	u32 val = sdhci_iproc_readl(host, (reg & ~3));
	u8 byte = val >> REG_OFFSET_IN_BITS(reg) & 0xff;
	return byte;
}

static inline void sdhci_iproc_writel(struct sdhci_host *host, u32 val, int reg)
{
	pr_debug("%s: writel [0x%02x] 0x%08x\n",
		 mmc_hostname(host->mmc), reg, val);

	writel(val, host->ioaddr + reg);

	if (host->clock <= 400000) {
		/* Round up to micro-second four SD clock delay */
		if (host->clock)
			udelay((4 * 1000000 + host->clock - 1) / host->clock);
		else
			udelay(10);
	}
}

/*
 * The Arasan has a bugette whereby it may lose the content of successive
 * writes to the same register that are within two SD-card clock cycles of
 * each other (a clock domain crossing problem). The data
 * register does not have this problem, which is just as well - otherwise we'd
 * have to nobble the DMA engine too.
 *
 * This wouldn't be a problem with the code except that we can only write the
 * controller with 32-bit writes.  So two different 16-bit registers are
 * written back to back creates the problem.
 *
 * In reality, this only happens when SDHCI_BLOCK_SIZE and SDHCI_BLOCK_COUNT
 * are written followed by SDHCI_TRANSFER_MODE and SDHCI_COMMAND.
 * The BLOCK_SIZE and BLOCK_COUNT are meaningless until a command issued so
 * the work around can be further optimized. We can keep shadow values of
 * BLOCK_SIZE, BLOCK_COUNT, and TRANSFER_MODE until a COMMAND is issued.
 * Then, write the BLOCK_SIZE+BLOCK_COUNT in a single 32-bit write followed
 * by the TRANSFER+COMMAND in another 32-bit write.
 */
static void sdhci_iproc_writew(struct sdhci_host *host, u16 val, int reg)
{
	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
	struct sdhci_iproc_host *iproc_host = sdhci_pltfm_priv(pltfm_host);
	u32 word_shift = REG_OFFSET_IN_BITS(reg);
	u32 mask = 0xffff << word_shift;
	u32 oldval, newval;

	if (reg == SDHCI_COMMAND) {
		/* Write the block now as we are issuing a command */
		if (iproc_host->shadow_blk != 0) {
			sdhci_iproc_writel(host, iproc_host->shadow_blk,
				SDHCI_BLOCK_SIZE);
			iproc_host->shadow_blk = 0;
		}
		oldval = iproc_host->shadow_cmd;
	} else if (reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) {
		/* Block size and count are stored in shadow reg */
		oldval = iproc_host->shadow_blk;
	} else {
		/* Read reg, all other registers are not shadowed */
		oldval = sdhci_iproc_readl(host, (reg & ~3));
	}
	newval = (oldval & ~mask) | (val << word_shift);

	if (reg == SDHCI_TRANSFER_MODE) {
		/* Save the transfer mode until the command is issued */
		iproc_host->shadow_cmd = newval;
	} else if (reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) {
		/* Save the block info until the command is issued */
		iproc_host->shadow_blk = newval;
	} else {
		/* Command or other regular 32-bit write */
		sdhci_iproc_writel(host, newval, reg & ~3);
	}
}

static void sdhci_iproc_writeb(struct sdhci_host *host, u8 val, int reg)
{
	u32 oldval = sdhci_iproc_readl(host, (reg & ~3));
	u32 byte_shift = REG_OFFSET_IN_BITS(reg);
	u32 mask = 0xff << byte_shift;
	u32 newval = (oldval & ~mask) | (val << byte_shift);

	sdhci_iproc_writel(host, newval, reg & ~3);
}

static const struct sdhci_ops sdhci_iproc_ops = {
	.read_l = sdhci_iproc_readl,
	.read_w = sdhci_iproc_readw,
	.read_b = sdhci_iproc_readb,
	.write_l = sdhci_iproc_writel,
	.write_w = sdhci_iproc_writew,
	.write_b = sdhci_iproc_writeb,
	.set_clock = sdhci_set_clock,
	.get_max_clock = sdhci_pltfm_clk_get_max_clock,
	.set_bus_width = sdhci_set_bus_width,
	.reset = sdhci_reset,
	.set_uhs_signaling = sdhci_set_uhs_signaling,
};

static const struct sdhci_pltfm_data sdhci_iproc_pltfm_data = {
	.quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK,
	.quirks2 = SDHCI_QUIRK2_ACMD23_BROKEN,
	.ops = &sdhci_iproc_ops,
};

static const struct sdhci_iproc_data iproc_data = {
	.pdata = &sdhci_iproc_pltfm_data,
	.caps = 0x05E90000,
	.caps1 = 0x00000064,
	.mmc_caps = MMC_CAP_1_8V_DDR,
};

static const struct sdhci_pltfm_data sdhci_bcm2835_pltfm_data = {
	.quirks = SDHCI_QUIRK_BROKEN_CARD_DETECTION |
		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
		  SDHCI_QUIRK_MISSING_CAPS,
	.ops = &sdhci_iproc_ops,
};

static const struct sdhci_iproc_data bcm2835_data = {
	.pdata = &sdhci_bcm2835_pltfm_data,
	.caps = SDHCI_CAN_VDD_330,
	.caps1 = 0x00000000,
	.mmc_caps = 0x00000000,
};

static const struct of_device_id sdhci_iproc_of_match[] = {
	{ .compatible = "brcm,bcm2835-sdhci", .data = &bcm2835_data },
	{ .compatible = "brcm,sdhci-iproc-cygnus", .data = &iproc_data },
	{ }
};
MODULE_DEVICE_TABLE(of, sdhci_iproc_of_match);

static int sdhci_iproc_probe(struct platform_device *pdev)
{
	const struct of_device_id *match;
	const struct sdhci_iproc_data *iproc_data;
	struct sdhci_host *host;
	struct sdhci_iproc_host *iproc_host;
	struct sdhci_pltfm_host *pltfm_host;
	int ret;

	match = of_match_device(sdhci_iproc_of_match, &pdev->dev);
	if (!match)
		return -EINVAL;
	iproc_data = match->data;

	host = sdhci_pltfm_init(pdev, iproc_data->pdata, sizeof(*iproc_host));
	if (IS_ERR(host))
		return PTR_ERR(host);

	pltfm_host = sdhci_priv(host);
	iproc_host = sdhci_pltfm_priv(pltfm_host);

	iproc_host->data = iproc_data;

	mmc_of_parse(host->mmc);
	sdhci_get_of_property(pdev);

	host->mmc->caps |= iproc_host->data->mmc_caps;

	pltfm_host->clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(pltfm_host->clk)) {
		ret = PTR_ERR(pltfm_host->clk);
		goto err;
	}
	ret = clk_prepare_enable(pltfm_host->clk);
	if (ret) {
		dev_err(&pdev->dev, "failed to enable host clk\n");
		goto err;
	}

	if (iproc_host->data->pdata->quirks & SDHCI_QUIRK_MISSING_CAPS) {
		host->caps = iproc_host->data->caps;
		host->caps1 = iproc_host->data->caps1;
	}

	ret = sdhci_add_host(host);
	if (ret)
		goto err_clk;

	return 0;

err_clk:
	clk_disable_unprepare(pltfm_host->clk);
err:
	sdhci_pltfm_free(pdev);
	return ret;
}

static struct platform_driver sdhci_iproc_driver = {
	.driver = {
		.name = "sdhci-iproc",
		.of_match_table = sdhci_iproc_of_match,
		.pm = SDHCI_PLTFM_PMOPS,
	},
	.probe = sdhci_iproc_probe,
	.remove = sdhci_pltfm_unregister,
};
module_platform_driver(sdhci_iproc_driver);

MODULE_AUTHOR("Broadcom");
MODULE_DESCRIPTION("IPROC SDHCI driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
b580c52d SB	1	/*
	2	* Copyright (C) 2014 Broadcom Corporation
	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of the GNU General Public License as
	6	* published by the Free Software Foundation version 2.
	7	*
	8	* This program is distributed "as is" WITHOUT ANY WARRANTY of any
	9	* kind, whether express or implied; without even the implied warranty
	10	* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*/
	13
	14	/*
	15	* iProc SDHCI platform driver
	16	*/
	17
	18	#include <linux/delay.h>
	19	#include <linux/module.h>
	20	#include <linux/mmc/host.h>
	21	#include <linux/of.h>
	22	#include <linux/of_device.h>
	23	#include "sdhci-pltfm.h"
	24
	25	struct sdhci_iproc_data {
	26	const struct sdhci_pltfm_data *pdata;
	27	u32 caps;
	28	u32 caps1;
b17b4ab8	29	u32 mmc_caps;
b580c52d SB	30	};
	31
	32	struct sdhci_iproc_host {
	33	const struct sdhci_iproc_data *data;
	34	u32 shadow_cmd;
	35	u32 shadow_blk;
	36	};
	37
	38	#define REG_OFFSET_IN_BITS(reg) ((reg) << 3 & 0x18)
	39
	40	static inline u32 sdhci_iproc_readl(struct sdhci_host *host, int reg)
	41	{
	42	u32 val = readl(host->ioaddr + reg);
	43
	44	pr_debug("%s: readl [0x%02x] 0x%08x\n",
	45	mmc_hostname(host->mmc), reg, val);
	46	return val;
	47	}
	48
	49	static u16 sdhci_iproc_readw(struct sdhci_host *host, int reg)
	50	{
	51	u32 val = sdhci_iproc_readl(host, (reg & ~3));
	52	u16 word = val >> REG_OFFSET_IN_BITS(reg) & 0xffff;
	53	return word;
	54	}
	55
	56	static u8 sdhci_iproc_readb(struct sdhci_host *host, int reg)
	57	{
	58	u32 val = sdhci_iproc_readl(host, (reg & ~3));
	59	u8 byte = val >> REG_OFFSET_IN_BITS(reg) & 0xff;
	60	return byte;
	61	}
	62
	63	static inline void sdhci_iproc_writel(struct sdhci_host *host, u32 val, int reg)
	64	{
	65	pr_debug("%s: writel [0x%02x] 0x%08x\n",
	66	mmc_hostname(host->mmc), reg, val);
	67
	68	writel(val, host->ioaddr + reg);
	69
	70	if (host->clock <= 400000) {
	71	/* Round up to micro-second four SD clock delay */
	72	if (host->clock)
	73	udelay((4 * 1000000 + host->clock - 1) / host->clock);
	74	else
	75	udelay(10);
	76	}
	77	}
	78
	79	/*
	80	* The Arasan has a bugette whereby it may lose the content of successive
	81	* writes to the same register that are within two SD-card clock cycles of
	82	* each other (a clock domain crossing problem). The data
	83	* register does not have this problem, which is just as well - otherwise we'd
	84	* have to nobble the DMA engine too.
	85	*
	86	* This wouldn't be a problem with the code except that we can only write the
	87	* controller with 32-bit writes. So two different 16-bit registers are
	88	* written back to back creates the problem.
	89	*
	90	* In reality, this only happens when SDHCI_BLOCK_SIZE and SDHCI_BLOCK_COUNT
	91	* are written followed by SDHCI_TRANSFER_MODE and SDHCI_COMMAND.
	92	* The BLOCK_SIZE and BLOCK_COUNT are meaningless until a command issued so
	93	* the work around can be further optimized. We can keep shadow values of
94	* BLOCK_SIZE, BLOCK_COUNT, and TRANSFER_MODE until a COMMAND is issued.
95	* Then, write the BLOCK_SIZE+BLOCK_COUNT in a single 32-bit write followed
96	* by the TRANSFER+COMMAND in another 32-bit write.
97	*/
98	static void sdhci_iproc_writew(struct sdhci_host *host, u16 val, int reg)
99	{
100	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
b1ddaa3d	101	struct sdhci_iproc_host *iproc_host = sdhci_pltfm_priv(pltfm_host);
b580c52d SB	102	u32 word_shift = REG_OFFSET_IN_BITS(reg);
	103	u32 mask = 0xffff << word_shift;
	104	u32 oldval, newval;
	105
	106	if (reg == SDHCI_COMMAND) {
	107	/* Write the block now as we are issuing a command */
	108	if (iproc_host->shadow_blk != 0) {
	109	sdhci_iproc_writel(host, iproc_host->shadow_blk,
	110	SDHCI_BLOCK_SIZE);
	111	iproc_host->shadow_blk = 0;
	112	}
	113	oldval = iproc_host->shadow_cmd;
	114	} else if (reg == SDHCI_BLOCK_SIZE \|\| reg == SDHCI_BLOCK_COUNT) {
	115	/* Block size and count are stored in shadow reg */
	116	oldval = iproc_host->shadow_blk;
	117	} else {
	118	/* Read reg, all other registers are not shadowed */
	119	oldval = sdhci_iproc_readl(host, (reg & ~3));
	120	}
	121	newval = (oldval & ~mask) \| (val << word_shift);
	122
	123	if (reg == SDHCI_TRANSFER_MODE) {
	124	/* Save the transfer mode until the command is issued */
	125	iproc_host->shadow_cmd = newval;
	126	} else if (reg == SDHCI_BLOCK_SIZE \|\| reg == SDHCI_BLOCK_COUNT) {
	127	/* Save the block info until the command is issued */
	128	iproc_host->shadow_blk = newval;
	129	} else {
	130	/* Command or other regular 32-bit write */
	131	sdhci_iproc_writel(host, newval, reg & ~3);
	132	}
	133	}
	134
	135	static void sdhci_iproc_writeb(struct sdhci_host *host, u8 val, int reg)
	136	{
	137	u32 oldval = sdhci_iproc_readl(host, (reg & ~3));
	138	u32 byte_shift = REG_OFFSET_IN_BITS(reg);
	139	u32 mask = 0xff << byte_shift;
	140	u32 newval = (oldval & ~mask) \| (val << byte_shift);
	141
	142	sdhci_iproc_writel(host, newval, reg & ~3);
	143	}
	144
	145	static const struct sdhci_ops sdhci_iproc_ops = {
	146	.read_l = sdhci_iproc_readl,
	147	.read_w = sdhci_iproc_readw,
	148	.read_b = sdhci_iproc_readb,
	149	.write_l = sdhci_iproc_writel,
	150	.write_w = sdhci_iproc_writew,
	151	.write_b = sdhci_iproc_writeb,
	152	.set_clock = sdhci_set_clock,
	153	.get_max_clock = sdhci_pltfm_clk_get_max_clock,
	154	.set_bus_width = sdhci_set_bus_width,
	155	.reset = sdhci_reset,
	156	.set_uhs_signaling = sdhci_set_uhs_signaling,
	157	};
	158
	159	static const struct sdhci_pltfm_data sdhci_iproc_pltfm_data = {
	160	.quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK,
	161	.quirks2 = SDHCI_QUIRK2_ACMD23_BROKEN,
	162	.ops = &sdhci_iproc_ops,
	163	};
	164
	165	static const struct sdhci_iproc_data iproc_data = {
166	.pdata = &sdhci_iproc_pltfm_data,
167	.caps = 0x05E90000,
168	.caps1 = 0x00000064,
b17b4ab8	169	.mmc_caps = MMC_CAP_1_8V_DDR,
b580c52d SB	170	};
b580c52d SB	171
77cb7d3a SW	172	static const struct sdhci_pltfm_data sdhci_bcm2835_pltfm_data = {
	173	.quirks = SDHCI_QUIRK_BROKEN_CARD_DETECTION \|
	174	SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK \|
	175	SDHCI_QUIRK_MISSING_CAPS,
	176	.ops = &sdhci_iproc_ops,
	177	};
	178
	179	static const struct sdhci_iproc_data bcm2835_data = {
	180	.pdata = &sdhci_bcm2835_pltfm_data,
	181	.caps = SDHCI_CAN_VDD_330,
	182	.caps1 = 0x00000000,
	183	.mmc_caps = 0x00000000,
	184	};
	185
b580c52d	186	static const struct of_device_id sdhci_iproc_of_match[] = {
77cb7d3a	187	{ .compatible = "brcm,bcm2835-sdhci", .data = &bcm2835_data },
b580c52d SB	188	{ .compatible = "brcm,sdhci-iproc-cygnus", .data = &iproc_data },
	189	{ }
	190	};
	191	MODULE_DEVICE_TABLE(of, sdhci_iproc_of_match);
	192
	193	static int sdhci_iproc_probe(struct platform_device *pdev)
	194	{
	195	const struct of_device_id *match;
	196	const struct sdhci_iproc_data *iproc_data;
	197	struct sdhci_host *host;
	198	struct sdhci_iproc_host *iproc_host;
	199	struct sdhci_pltfm_host *pltfm_host;
	200	int ret;
	201
	202	match = of_match_device(sdhci_iproc_of_match, &pdev->dev);
	203	if (!match)
	204	return -EINVAL;
	205	iproc_data = match->data;
	206
	207	host = sdhci_pltfm_init(pdev, iproc_data->pdata, sizeof(*iproc_host));
	208	if (IS_ERR(host))
	209	return PTR_ERR(host);
	210
	211	pltfm_host = sdhci_priv(host);
	212	iproc_host = sdhci_pltfm_priv(pltfm_host);
	213
	214	iproc_host->data = iproc_data;
	215
	216	mmc_of_parse(host->mmc);
	217	sdhci_get_of_property(pdev);
	218
b17b4ab8	219	host->mmc->caps \|= iproc_host->data->mmc_caps;
b580c52d SB	220
	221	pltfm_host->clk = devm_clk_get(&pdev->dev, NULL);
	222	if (IS_ERR(pltfm_host->clk)) {
	223	ret = PTR_ERR(pltfm_host->clk);
	224	goto err;
	225	}
9f24b0f2 SW	226	ret = clk_prepare_enable(pltfm_host->clk);
	227	if (ret) {
	228	dev_err(&pdev->dev, "failed to enable host clk\n");
	229	goto err;
	230	}
b580c52d SB	231
	232	if (iproc_host->data->pdata->quirks & SDHCI_QUIRK_MISSING_CAPS) {
	233	host->caps = iproc_host->data->caps;
	234	host->caps1 = iproc_host->data->caps1;
	235	}
	236
1d6ad057 SW	237	ret = sdhci_add_host(host);
1d6ad057 SW	238	if (ret)
9f24b0f2	239	goto err_clk;
1d6ad057 SW	240
1d6ad057 SW	241	return 0;
b580c52d	242
9f24b0f2 SW	243	err_clk:
9f24b0f2 SW	244	clk_disable_unprepare(pltfm_host->clk);
b580c52d SB	245	err:
	246	sdhci_pltfm_free(pdev);
	247	return ret;
	248	}
	249
b580c52d SB	250	static struct platform_driver sdhci_iproc_driver = {
	251	.driver = {
	252	.name = "sdhci-iproc",
	253	.of_match_table = sdhci_iproc_of_match,
	254	.pm = SDHCI_PLTFM_PMOPS,
	255	},
	256	.probe = sdhci_iproc_probe,
d1a13c5e	257	.remove = sdhci_pltfm_unregister,
b580c52d SB	258	};
	259	module_platform_driver(sdhci_iproc_driver);
	260
	261	MODULE_AUTHOR("Broadcom");
	262	MODULE_DESCRIPTION("IPROC SDHCI driver");
	263	MODULE_LICENSE("GPL v2");