drivers/mmc/host/dw_mmc-rockchip.c - linux - Git at Google

 /*
  * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
  *
  * 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; either version 2 of the License, or
  * (at your option) any later version.
  */

 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/clk.h>
 #include <linux/mmc/host.h>
 #include <linux/mmc/dw_mmc.h>
 #include <linux/of_address.h>
 #include <linux/slab.h>

 #include "dw_mmc.h"
 #include "dw_mmc-pltfm.h"

 #define RK3288_CLKGEN_DIV       2

 struct dw_mci_rockchip_priv_data {
 	struct clk		*drv_clk;
 	struct clk		*sample_clk;
 	int			default_sample_phase;
 };

 static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios)
 {
 	struct dw_mci_rockchip_priv_data *priv = host->priv;
 	int ret;
 	unsigned int cclkin;
 	u32 bus_hz;

 	if (ios->clock == 0)
 		return;

 	/*
 	 * cclkin: source clock of mmc controller
 	 * bus_hz: card interface clock generated by CLKGEN
 	 * bus_hz = cclkin / RK3288_CLKGEN_DIV
 	 * ios->clock = (div == 0) ? bus_hz : (bus_hz / (2 * div))
 	 *
 	 * Note: div can only be 0 or 1
 	 *       if DDR50 8bit mode(only emmc work in 8bit mode),
 	 *       div must be set 1
 	 */
 	if (ios->bus_width == MMC_BUS_WIDTH_8 &&
 	    ios->timing == MMC_TIMING_MMC_DDR52)
 		cclkin = 2 * ios->clock * RK3288_CLKGEN_DIV;
 	else
 		cclkin = ios->clock * RK3288_CLKGEN_DIV;

 	ret = clk_set_rate(host->ciu_clk, cclkin);
 	if (ret)
 		dev_warn(host->dev, "failed to set rate %uHz\n", ios->clock);

 	bus_hz = clk_get_rate(host->ciu_clk) / RK3288_CLKGEN_DIV;
 	if (bus_hz != host->bus_hz) {
 		host->bus_hz = bus_hz;
 		/* force dw_mci_setup_bus() */
 		host->current_speed = 0;
 	}

 	/* Make sure we use phases which we can enumerate with */
 	if (!IS_ERR(priv->sample_clk))
 		clk_set_phase(priv->sample_clk, priv->default_sample_phase);
 }

 #define NUM_PHASES			360
 #define TUNING_ITERATION_TO_PHASE(i)	(DIV_ROUND_UP((i) * 360, NUM_PHASES))

 static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode)
 {
 	struct dw_mci *host = slot->host;
 	struct dw_mci_rockchip_priv_data *priv = host->priv;
 	struct mmc_host *mmc = slot->mmc;
 	int ret = 0;
 	int i;
 	bool v, prev_v = 0, first_v;
 	struct range_t {
 		int start;
 		int end; /* inclusive */
 	};
 	struct range_t *ranges;
 	unsigned int range_count = 0;
 	int longest_range_len = -1;
 	int longest_range = -1;
 	int middle_phase;

 	if (IS_ERR(priv->sample_clk)) {
 		dev_err(host->dev, "Tuning clock (sample_clk) not defined.\n");
 		return -EIO;
 	}

 	ranges = kmalloc_array(NUM_PHASES / 2 + 1, sizeof(*ranges), GFP_KERNEL);
 	if (!ranges)
 		return -ENOMEM;

 	/* Try each phase and extract good ranges */
 	for (i = 0; i < NUM_PHASES; ) {
 		clk_set_phase(priv->sample_clk, TUNING_ITERATION_TO_PHASE(i));

 		v = !mmc_send_tuning(mmc, opcode, NULL);

 		if (i == 0)
 			first_v = v;

 		if ((!prev_v) && v) {
 			range_count++;
 			ranges[range_count-1].start = i;
 		}
 		if (v) {
 			ranges[range_count-1].end = i;
 			i++;
 		} else if (i == NUM_PHASES - 1) {
 			/* No extra skipping rules if we're at the end */
 			i++;
 		} else {
 			/*
 			 * No need to check too close to an invalid
 			 * one since testing bad phases is slow.  Skip
 			 * 20 degrees.
 			 */
 			i += DIV_ROUND_UP(20 * NUM_PHASES, 360);

 			/* Always test the last one */
 			if (i >= NUM_PHASES)
 				i = NUM_PHASES - 1;
 		}

 		prev_v = v;
 	}

 	if (range_count == 0) {
 		dev_warn(host->dev, "All phases bad!");
 		ret = -EIO;
 		goto free;
 	}

 	/* wrap around case, merge the end points */
 	if ((range_count > 1) && first_v && v) {
 		ranges[0].start = ranges[range_count-1].start;
 		range_count--;
 	}

 	if (ranges[0].start == 0 && ranges[0].end == NUM_PHASES - 1) {
 		clk_set_phase(priv->sample_clk, priv->default_sample_phase);
 		dev_info(host->dev, "All phases work, using default phase %d.",
 			 priv->default_sample_phase);
 		goto free;
 	}

 	/* Find the longest range */
 	for (i = 0; i < range_count; i++) {
 		int len = (ranges[i].end - ranges[i].start + 1);

 		if (len < 0)
 			len += NUM_PHASES;

 		if (longest_range_len < len) {
 			longest_range_len = len;
 			longest_range = i;
 		}

 		dev_dbg(host->dev, "Good phase range %d-%d (%d len)\n",
 			TUNING_ITERATION_TO_PHASE(ranges[i].start),
 			TUNING_ITERATION_TO_PHASE(ranges[i].end),
 			len
 		);
 	}

 	dev_dbg(host->dev, "Best phase range %d-%d (%d len)\n",
 		TUNING_ITERATION_TO_PHASE(ranges[longest_range].start),
 		TUNING_ITERATION_TO_PHASE(ranges[longest_range].end),
 		longest_range_len
 	);

 	middle_phase = ranges[longest_range].start + longest_range_len / 2;
 	middle_phase %= NUM_PHASES;
 	dev_info(host->dev, "Successfully tuned phase to %d\n",
 		 TUNING_ITERATION_TO_PHASE(middle_phase));

 	clk_set_phase(priv->sample_clk,
 		      TUNING_ITERATION_TO_PHASE(middle_phase));

 free:
 	kfree(ranges);
 	return ret;
 }

 static int dw_mci_rk3288_parse_dt(struct dw_mci *host)
 {
 	struct device_node *np = host->dev->of_node;
 	struct dw_mci_rockchip_priv_data *priv;

 	priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;

 	if (of_property_read_u32(np, "rockchip,default-sample-phase",
 					&priv->default_sample_phase))
 		priv->default_sample_phase = 0;

 	priv->drv_clk = devm_clk_get(host->dev, "ciu-drive");
 	if (IS_ERR(priv->drv_clk))
 		dev_dbg(host->dev, "ciu_drv not available\n");

 	priv->sample_clk = devm_clk_get(host->dev, "ciu-sample");
 	if (IS_ERR(priv->sample_clk))
 		dev_dbg(host->dev, "ciu_sample not available\n");

 	host->priv = priv;

 	return 0;
 }

 static int dw_mci_rockchip_init(struct dw_mci *host)
 {
 	/* It is slot 8 on Rockchip SoCs */
 	host->sdio_id0 = 8;

 	/* It needs this quirk on all Rockchip SoCs */
 	host->pdata->quirks |= DW_MCI_QUIRK_BROKEN_DTO;

 	if (of_device_is_compatible(host->dev->of_node,
 				    "rockchip,rk3288-dw-mshc"))
 		host->bus_hz /= RK3288_CLKGEN_DIV;

 	return 0;
 }

 /* Common capabilities of RK3288 SoC */
 static unsigned long dw_mci_rk3288_dwmmc_caps[4] = {
 	MMC_CAP_ERASE,
 	MMC_CAP_ERASE,
 	MMC_CAP_ERASE,
 	MMC_CAP_ERASE,
 };

 static const struct dw_mci_drv_data rk2928_drv_data = {
 	.init			= dw_mci_rockchip_init,
 };

 static const struct dw_mci_drv_data rk3288_drv_data = {
 	.caps			= dw_mci_rk3288_dwmmc_caps,
 	.set_ios		= dw_mci_rk3288_set_ios,
 	.execute_tuning		= dw_mci_rk3288_execute_tuning,
 	.parse_dt		= dw_mci_rk3288_parse_dt,
 	.init			= dw_mci_rockchip_init,
 };

 static const struct of_device_id dw_mci_rockchip_match[] = {
 	{ .compatible = "rockchip,rk2928-dw-mshc",
 		.data = &rk2928_drv_data },
 	{ .compatible = "rockchip,rk3288-dw-mshc",
 		.data = &rk3288_drv_data },
 	{},
 };
 MODULE_DEVICE_TABLE(of, dw_mci_rockchip_match);

 static int dw_mci_rockchip_probe(struct platform_device *pdev)
 {
 	const struct dw_mci_drv_data *drv_data;
 	const struct of_device_id *match;

 	if (!pdev->dev.of_node)
 		return -ENODEV;

 	match = of_match_node(dw_mci_rockchip_match, pdev->dev.of_node);
 	drv_data = match->data;

 	return dw_mci_pltfm_register(pdev, drv_data);
 }

 static struct platform_driver dw_mci_rockchip_pltfm_driver = {
 	.probe		= dw_mci_rockchip_probe,
 	.remove		= dw_mci_pltfm_remove,
 	.driver		= {
 		.name		= "dwmmc_rockchip",
 		.of_match_table	= dw_mci_rockchip_match,
 		.pm		= &dw_mci_pltfm_pmops,
 	},
 };

 module_platform_driver(dw_mci_rockchip_pltfm_driver);

 MODULE_AUTHOR("Addy Ke <addy.ke@rock-chips.com>");
 MODULE_DESCRIPTION("Rockchip Specific DW-MSHC Driver Extension");
 MODULE_ALIAS("platform:dwmmc_rockchip");
 MODULE_LICENSE("GPL v2");
	/*
	* Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
	*
	* 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; either version 2 of the License, or
	* (at your option) any later version.
	*/

	#include <linux/module.h>
	#include <linux/platform_device.h>
	#include <linux/clk.h>
	#include <linux/mmc/host.h>
	#include <linux/mmc/dw_mmc.h>
	#include <linux/of_address.h>
	#include <linux/slab.h>

	#include "dw_mmc.h"
	#include "dw_mmc-pltfm.h"

	#define RK3288_CLKGEN_DIV 2

	struct dw_mci_rockchip_priv_data {
	struct clk *drv_clk;
	struct clk *sample_clk;
	int default_sample_phase;
	};

	static void dw_mci_rk3288_set_ios(struct dw_mci host, struct mmc_ios ios)
	{
	struct dw_mci_rockchip_priv_data *priv = host->priv;
	int ret;
	unsigned int cclkin;
	u32 bus_hz;

	if (ios->clock == 0)
	return;

	/*
	* cclkin: source clock of mmc controller
	* bus_hz: card interface clock generated by CLKGEN
	* bus_hz = cclkin / RK3288_CLKGEN_DIV
	* ios->clock = (div == 0) ? bus_hz : (bus_hz / (2 * div))
	*
	* Note: div can only be 0 or 1
	* if DDR50 8bit mode(only emmc work in 8bit mode),
	* div must be set 1
	*/
	if (ios->bus_width == MMC_BUS_WIDTH_8 &&
	ios->timing == MMC_TIMING_MMC_DDR52)
	cclkin = 2 * ios->clock * RK3288_CLKGEN_DIV;
	else
	cclkin = ios->clock * RK3288_CLKGEN_DIV;

	ret = clk_set_rate(host->ciu_clk, cclkin);
	if (ret)
	dev_warn(host->dev, "failed to set rate %uHz\n", ios->clock);

	bus_hz = clk_get_rate(host->ciu_clk) / RK3288_CLKGEN_DIV;
	if (bus_hz != host->bus_hz) {
	host->bus_hz = bus_hz;
	/* force dw_mci_setup_bus() */
	host->current_speed = 0;
	}

	/* Make sure we use phases which we can enumerate with */
	if (!IS_ERR(priv->sample_clk))
	clk_set_phase(priv->sample_clk, priv->default_sample_phase);
	}

	#define NUM_PHASES 360
	#define TUNING_ITERATION_TO_PHASE(i) (DIV_ROUND_UP((i) * 360, NUM_PHASES))

	static int dw_mci_rk3288_execute_tuning(struct dw_mci_slot *slot, u32 opcode)
	{
	struct dw_mci *host = slot->host;
	struct dw_mci_rockchip_priv_data *priv = host->priv;
	struct mmc_host *mmc = slot->mmc;
	int ret = 0;
	int i;
	bool v, prev_v = 0, first_v;
	struct range_t {
	int start;
	int end; /* inclusive */
	};
	struct range_t *ranges;
	unsigned int range_count = 0;
	int longest_range_len = -1;
	int longest_range = -1;
	int middle_phase;

	if (IS_ERR(priv->sample_clk)) {
	dev_err(host->dev, "Tuning clock (sample_clk) not defined.\n");
	return -EIO;
	}

	ranges = kmalloc_array(NUM_PHASES / 2 + 1, sizeof(*ranges), GFP_KERNEL);
	if (!ranges)
	return -ENOMEM;

	/* Try each phase and extract good ranges */
	for (i = 0; i < NUM_PHASES; ) {
	clk_set_phase(priv->sample_clk, TUNING_ITERATION_TO_PHASE(i));

	v = !mmc_send_tuning(mmc, opcode, NULL);

	if (i == 0)
	first_v = v;

	if ((!prev_v) && v) {
	range_count++;
	ranges[range_count-1].start = i;
	}
	if (v) {
	ranges[range_count-1].end = i;
	i++;
	} else if (i == NUM_PHASES - 1) {
	/* No extra skipping rules if we're at the end */
	i++;
	} else {
	/*
	* No need to check too close to an invalid
	* one since testing bad phases is slow. Skip
	* 20 degrees.
	*/
	i += DIV_ROUND_UP(20 * NUM_PHASES, 360);

	/* Always test the last one */
	if (i >= NUM_PHASES)
	i = NUM_PHASES - 1;
	}

	prev_v = v;
	}

	if (range_count == 0) {
	dev_warn(host->dev, "All phases bad!");
	ret = -EIO;
	goto free;
	}

	/* wrap around case, merge the end points */
	if ((range_count > 1) && first_v && v) {
	ranges[0].start = ranges[range_count-1].start;
	range_count--;
	}

	if (ranges[0].start == 0 && ranges[0].end == NUM_PHASES - 1) {
	clk_set_phase(priv->sample_clk, priv->default_sample_phase);
	dev_info(host->dev, "All phases work, using default phase %d.",
	priv->default_sample_phase);
	goto free;
	}

	/* Find the longest range */
	for (i = 0; i < range_count; i++) {
	int len = (ranges[i].end - ranges[i].start + 1);

	if (len < 0)
	len += NUM_PHASES;

	if (longest_range_len < len) {
	longest_range_len = len;
	longest_range = i;
	}

	dev_dbg(host->dev, "Good phase range %d-%d (%d len)\n",
	TUNING_ITERATION_TO_PHASE(ranges[i].start),
	TUNING_ITERATION_TO_PHASE(ranges[i].end),
	len
	);
	}

	dev_dbg(host->dev, "Best phase range %d-%d (%d len)\n",
	TUNING_ITERATION_TO_PHASE(ranges[longest_range].start),
	TUNING_ITERATION_TO_PHASE(ranges[longest_range].end),
	longest_range_len
	);

	middle_phase = ranges[longest_range].start + longest_range_len / 2;
	middle_phase %= NUM_PHASES;
	dev_info(host->dev, "Successfully tuned phase to %d\n",
	TUNING_ITERATION_TO_PHASE(middle_phase));

	clk_set_phase(priv->sample_clk,
	TUNING_ITERATION_TO_PHASE(middle_phase));

	free:
	kfree(ranges);
	return ret;
	}

	static int dw_mci_rk3288_parse_dt(struct dw_mci *host)
	{
	struct device_node *np = host->dev->of_node;
	struct dw_mci_rockchip_priv_data *priv;

	priv = devm_kzalloc(host->dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
	return -ENOMEM;

	if (of_property_read_u32(np, "rockchip,default-sample-phase",
	&priv->default_sample_phase))
	priv->default_sample_phase = 0;

	priv->drv_clk = devm_clk_get(host->dev, "ciu-drive");
	if (IS_ERR(priv->drv_clk))
	dev_dbg(host->dev, "ciu_drv not available\n");

	priv->sample_clk = devm_clk_get(host->dev, "ciu-sample");
	if (IS_ERR(priv->sample_clk))
	dev_dbg(host->dev, "ciu_sample not available\n");

	host->priv = priv;

	return 0;
	}

	static int dw_mci_rockchip_init(struct dw_mci *host)
	{
	/* It is slot 8 on Rockchip SoCs */
	host->sdio_id0 = 8;

	/* It needs this quirk on all Rockchip SoCs */
	host->pdata->quirks \|= DW_MCI_QUIRK_BROKEN_DTO;

	if (of_device_is_compatible(host->dev->of_node,
	"rockchip,rk3288-dw-mshc"))
	host->bus_hz /= RK3288_CLKGEN_DIV;

	return 0;
	}

	/* Common capabilities of RK3288 SoC */
	static unsigned long dw_mci_rk3288_dwmmc_caps[4] = {
	MMC_CAP_ERASE,
	MMC_CAP_ERASE,
	MMC_CAP_ERASE,
	MMC_CAP_ERASE,
	};

	static const struct dw_mci_drv_data rk2928_drv_data = {
	.init = dw_mci_rockchip_init,
	};

	static const struct dw_mci_drv_data rk3288_drv_data = {
	.caps = dw_mci_rk3288_dwmmc_caps,
	.set_ios = dw_mci_rk3288_set_ios,
	.execute_tuning = dw_mci_rk3288_execute_tuning,
	.parse_dt = dw_mci_rk3288_parse_dt,
	.init = dw_mci_rockchip_init,
	};

	static const struct of_device_id dw_mci_rockchip_match[] = {
	{ .compatible = "rockchip,rk2928-dw-mshc",
	.data = &rk2928_drv_data },
	{ .compatible = "rockchip,rk3288-dw-mshc",
	.data = &rk3288_drv_data },
	{},
	};
	MODULE_DEVICE_TABLE(of, dw_mci_rockchip_match);

	static int dw_mci_rockchip_probe(struct platform_device *pdev)
	{
	const struct dw_mci_drv_data *drv_data;
	const struct of_device_id *match;

	if (!pdev->dev.of_node)
	return -ENODEV;

	match = of_match_node(dw_mci_rockchip_match, pdev->dev.of_node);
	drv_data = match->data;

	return dw_mci_pltfm_register(pdev, drv_data);
	}

	static struct platform_driver dw_mci_rockchip_pltfm_driver = {
	.probe = dw_mci_rockchip_probe,
	.remove = dw_mci_pltfm_remove,
	.driver = {
	.name = "dwmmc_rockchip",
	.of_match_table = dw_mci_rockchip_match,
	.pm = &dw_mci_pltfm_pmops,
	},
	};

	module_platform_driver(dw_mci_rockchip_pltfm_driver);

	MODULE_AUTHOR("Addy Ke <addy.ke@rock-chips.com>");
	MODULE_DESCRIPTION("Rockchip Specific DW-MSHC Driver Extension");
	MODULE_ALIAS("platform:dwmmc_rockchip");
	MODULE_LICENSE("GPL v2");