[deliverable/linux.git] / drivers / memory / samsung / exynos-srom.c

/*
 * Copyright (c) 2015 Samsung Electronics Co., Ltd.
 *	      http://www.samsung.com/
 *
 * EXYNOS - SROM Controller support
 * Author: Pankaj Dubey <pankaj.dubey@samsung.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

#include "exynos-srom.h"

static const unsigned long exynos_srom_offsets[] = {
	/* SROM side */
	EXYNOS_SROM_BW,
	EXYNOS_SROM_BC0,
	EXYNOS_SROM_BC1,
	EXYNOS_SROM_BC2,
	EXYNOS_SROM_BC3,
};

/**
 * struct exynos_srom_reg_dump: register dump of SROM Controller registers.
 * @offset: srom register offset from the controller base address.
 * @value: the value of register under the offset.
 */
struct exynos_srom_reg_dump {
	u32     offset;
	u32     value;
};

/**
 * struct exynos_srom: platform data for exynos srom controller driver.
 * @dev: platform device pointer
 * @reg_base: srom base address
 * @reg_offset: exynos_srom_reg_dump pointer to hold offset and its value.
 */
struct exynos_srom {
	struct device *dev;
	void __iomem *reg_base;
	struct exynos_srom_reg_dump *reg_offset;
};

static struct exynos_srom_reg_dump *exynos_srom_alloc_reg_dump(
		const unsigned long *rdump,
		unsigned long nr_rdump)
{
	struct exynos_srom_reg_dump *rd;
	unsigned int i;

	rd = kcalloc(nr_rdump, sizeof(*rd), GFP_KERNEL);
	if (!rd)
		return NULL;

	for (i = 0; i < nr_rdump; ++i)
		rd[i].offset = rdump[i];

	return rd;
}

static int exynos_srom_configure_bank(struct exynos_srom *srom,
				      struct device_node *np)
{
	u32 bank, width, pmc = 0;
	u32 timing[6];
	u32 cs, bw;

	if (of_property_read_u32(np, "reg", &bank))
		return -EINVAL;
	if (of_property_read_u32(np, "reg-io-width", &width))
		width = 1;
	if (of_property_read_bool(np, "samsung,srom-page-mode"))
		pmc = 1 << EXYNOS_SROM_BCX__PMC__SHIFT;
	if (of_property_read_u32_array(np, "samsung,srom-timing", timing,
				       ARRAY_SIZE(timing)))
		return -EINVAL;

	bank *= 4; /* Convert bank into shift/offset */

	cs = 1 << EXYNOS_SROM_BW__BYTEENABLE__SHIFT;
	if (width == 2)
		cs |= 1 << EXYNOS_SROM_BW__DATAWIDTH__SHIFT;

	bw = __raw_readl(srom->reg_base + EXYNOS_SROM_BW);
	bw = (bw & ~(EXYNOS_SROM_BW__CS_MASK << bank)) | (cs << bank);
	__raw_writel(bw, srom->reg_base + EXYNOS_SROM_BW);

	__raw_writel(pmc | (timing[0] << EXYNOS_SROM_BCX__TACP__SHIFT) |
		    (timing[1] << EXYNOS_SROM_BCX__TCAH__SHIFT) |
		    (timing[2] << EXYNOS_SROM_BCX__TCOH__SHIFT) |
		    (timing[3] << EXYNOS_SROM_BCX__TACC__SHIFT) |
		    (timing[4] << EXYNOS_SROM_BCX__TCOS__SHIFT) |
		    (timing[5] << EXYNOS_SROM_BCX__TACS__SHIFT),
		    srom->reg_base + EXYNOS_SROM_BC0 + bank);

	return 0;
}

static int exynos_srom_probe(struct platform_device *pdev)
{
	struct device_node *np, *child;
	struct exynos_srom *srom;
	struct device *dev = &pdev->dev;
	bool bad_bank_config = false;

	np = dev->of_node;
	if (!np) {
		dev_err(&pdev->dev, "could not find device info\n");
		return -EINVAL;
	}

	srom = devm_kzalloc(&pdev->dev,
			sizeof(struct exynos_srom), GFP_KERNEL);
	if (!srom)
		return -ENOMEM;

	srom->dev = dev;
	srom->reg_base = of_iomap(np, 0);
	if (!srom->reg_base) {
		dev_err(&pdev->dev, "iomap of exynos srom controller failed\n");
		return -ENOMEM;
	}

	platform_set_drvdata(pdev, srom);

	srom->reg_offset = exynos_srom_alloc_reg_dump(exynos_srom_offsets,
			sizeof(exynos_srom_offsets));
	if (!srom->reg_offset) {
		iounmap(srom->reg_base);
		return -ENOMEM;
	}

	for_each_child_of_node(np, child) {
		if (exynos_srom_configure_bank(srom, child)) {
			dev_err(dev,
				"Could not decode bank configuration for %s\n",
				child->name);
			bad_bank_config = true;
		}
	}

	/*
	 * If any bank failed to configure, we still provide suspend/resume,
	 * but do not probe child devices
	 */
	if (bad_bank_config)
		return 0;

	return of_platform_populate(np, NULL, NULL, dev);
}

static int exynos_srom_remove(struct platform_device *pdev)
{
	struct exynos_srom *srom = platform_get_drvdata(pdev);

	kfree(srom->reg_offset);
	iounmap(srom->reg_base);

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static void exynos_srom_save(void __iomem *base,
				    struct exynos_srom_reg_dump *rd,
				    unsigned int num_regs)
{
	for (; num_regs > 0; --num_regs, ++rd)
		rd->value = readl(base + rd->offset);
}

static void exynos_srom_restore(void __iomem *base,
				      const struct exynos_srom_reg_dump *rd,
				      unsigned int num_regs)
{
	for (; num_regs > 0; --num_regs, ++rd)
		writel(rd->value, base + rd->offset);
}

static int exynos_srom_suspend(struct device *dev)
{
	struct exynos_srom *srom = dev_get_drvdata(dev);

	exynos_srom_save(srom->reg_base, srom->reg_offset,
				ARRAY_SIZE(exynos_srom_offsets));
	return 0;
}

static int exynos_srom_resume(struct device *dev)
{
	struct exynos_srom *srom = dev_get_drvdata(dev);

	exynos_srom_restore(srom->reg_base, srom->reg_offset,
				ARRAY_SIZE(exynos_srom_offsets));
	return 0;
}
#endif

static const struct of_device_id of_exynos_srom_ids[] = {
	{
		.compatible	= "samsung,exynos4210-srom",
	},
	{},
};
MODULE_DEVICE_TABLE(of, of_exynos_srom_ids);

static SIMPLE_DEV_PM_OPS(exynos_srom_pm_ops, exynos_srom_suspend, exynos_srom_resume);

static struct platform_driver exynos_srom_driver = {
	.probe = exynos_srom_probe,
	.remove = exynos_srom_remove,
	.driver = {
		.name = "exynos-srom",
		.of_match_table = of_exynos_srom_ids,
		.pm = &exynos_srom_pm_ops,
	},
};
module_platform_driver(exynos_srom_driver);

MODULE_AUTHOR("Pankaj Dubey <pankaj.dubey@samsung.com>");
MODULE_DESCRIPTION("Exynos SROM Controller Driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
a8aabb91 PD	1	/*
	2	* Copyright (c) 2015 Samsung Electronics Co., Ltd.
	3	* http://www.samsung.com/
	4	*
	5	* EXYNOS - SROM Controller support
	6	* Author: Pankaj Dubey <pankaj.dubey@samsung.com>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11	*/
	12
	13	#include <linux/io.h>
	14	#include <linux/module.h>
	15	#include <linux/of.h>
	16	#include <linux/of_address.h>
8ac2266d	17	#include <linux/of_platform.h>
a8aabb91 PD	18	#include <linux/platform_device.h>
	19	#include <linux/slab.h>
	20
	21	#include "exynos-srom.h"
	22
	23	static const unsigned long exynos_srom_offsets[] = {
	24	/* SROM side */
	25	EXYNOS_SROM_BW,
	26	EXYNOS_SROM_BC0,
	27	EXYNOS_SROM_BC1,
	28	EXYNOS_SROM_BC2,
	29	EXYNOS_SROM_BC3,
	30	};
	31
	32	/**
	33	* struct exynos_srom_reg_dump: register dump of SROM Controller registers.
	34	* @offset: srom register offset from the controller base address.
	35	* @value: the value of register under the offset.
	36	*/
	37	struct exynos_srom_reg_dump {
	38	u32 offset;
	39	u32 value;
	40	};
	41
	42	/**
	43	* struct exynos_srom: platform data for exynos srom controller driver.
	44	* @dev: platform device pointer
	45	* @reg_base: srom base address
	46	* @reg_offset: exynos_srom_reg_dump pointer to hold offset and its value.
	47	*/
	48	struct exynos_srom {
	49	struct device *dev;
	50	void __iomem *reg_base;
	51	struct exynos_srom_reg_dump *reg_offset;
	52	};
	53
	54	static struct exynos_srom_reg_dump *exynos_srom_alloc_reg_dump(
	55	const unsigned long *rdump,
	56	unsigned long nr_rdump)
	57	{
	58	struct exynos_srom_reg_dump *rd;
	59	unsigned int i;
	60
	61	rd = kcalloc(nr_rdump, sizeof(*rd), GFP_KERNEL);
	62	if (!rd)
	63	return NULL;
	64
	65	for (i = 0; i < nr_rdump; ++i)
	66	rd[i].offset = rdump[i];
	67
	68	return rd;
	69	}
	70
8ac2266d PF	71	static int exynos_srom_configure_bank(struct exynos_srom *srom,
	72	struct device_node *np)
	73	{
	74	u32 bank, width, pmc = 0;
	75	u32 timing[6];
	76	u32 cs, bw;
	77
	78	if (of_property_read_u32(np, "reg", &bank))
	79	return -EINVAL;
	80	if (of_property_read_u32(np, "reg-io-width", &width))
	81	width = 1;
	82	if (of_property_read_bool(np, "samsung,srom-page-mode"))
	83	pmc = 1 << EXYNOS_SROM_BCX__PMC__SHIFT;
	84	if (of_property_read_u32_array(np, "samsung,srom-timing", timing,
	85	ARRAY_SIZE(timing)))
	86	return -EINVAL;
	87
	88	bank = 4; / Convert bank into shift/offset */
	89
	90	cs = 1 << EXYNOS_SROM_BW__BYTEENABLE__SHIFT;
	91	if (width == 2)
	92	cs \|= 1 << EXYNOS_SROM_BW__DATAWIDTH__SHIFT;
	93
	94	bw = __raw_readl(srom->reg_base + EXYNOS_SROM_BW);
	95	bw = (bw & ~(EXYNOS_SROM_BW__CS_MASK << bank)) \| (cs << bank);
	96	__raw_writel(bw, srom->reg_base + EXYNOS_SROM_BW);
	97
	98	__raw_writel(pmc \| (timing[0] << EXYNOS_SROM_BCX__TACP__SHIFT) \|
	99	(timing[1] << EXYNOS_SROM_BCX__TCAH__SHIFT) \|
	100	(timing[2] << EXYNOS_SROM_BCX__TCOH__SHIFT) \|
	101	(timing[3] << EXYNOS_SROM_BCX__TACC__SHIFT) \|
	102	(timing[4] << EXYNOS_SROM_BCX__TCOS__SHIFT) \|
	103	(timing[5] << EXYNOS_SROM_BCX__TACS__SHIFT),
	104	srom->reg_base + EXYNOS_SROM_BC0 + bank);
	105
	106	return 0;
	107	}
	108
a8aabb91 PD	109	static int exynos_srom_probe(struct platform_device *pdev)
a8aabb91 PD	110	{
8ac2266d	111	struct device_node np, child;
a8aabb91 PD	112	struct exynos_srom *srom;
a8aabb91 PD	113	struct device *dev = &pdev->dev;
8ac2266d	114	bool bad_bank_config = false;
a8aabb91 PD	115
	116	np = dev->of_node;
	117	if (!np) {
	118	dev_err(&pdev->dev, "could not find device info\n");
	119	return -EINVAL;
	120	}
	121
	122	srom = devm_kzalloc(&pdev->dev,
	123	sizeof(struct exynos_srom), GFP_KERNEL);
	124	if (!srom)
	125	return -ENOMEM;
	126
	127	srom->dev = dev;
	128	srom->reg_base = of_iomap(np, 0);
	129	if (!srom->reg_base) {
	130	dev_err(&pdev->dev, "iomap of exynos srom controller failed\n");
	131	return -ENOMEM;
	132	}
	133
	134	platform_set_drvdata(pdev, srom);
	135
	136	srom->reg_offset = exynos_srom_alloc_reg_dump(exynos_srom_offsets,
	137	sizeof(exynos_srom_offsets));
	138	if (!srom->reg_offset) {
	139	iounmap(srom->reg_base);
	140	return -ENOMEM;
	141	}
	142
8ac2266d PF	143	for_each_child_of_node(np, child) {
	144	if (exynos_srom_configure_bank(srom, child)) {
	145	dev_err(dev,
	146	"Could not decode bank configuration for %s\n",
	147	child->name);
	148	bad_bank_config = true;
	149	}
	150	}
	151
	152	/*
	153	* If any bank failed to configure, we still provide suspend/resume,
	154	* but do not probe child devices
	155	*/
	156	if (bad_bank_config)
	157	return 0;
	158
	159	return of_platform_populate(np, NULL, NULL, dev);
a8aabb91 PD	160	}
	161
	162	static int exynos_srom_remove(struct platform_device *pdev)
	163	{
	164	struct exynos_srom *srom = platform_get_drvdata(pdev);
	165
	166	kfree(srom->reg_offset);
	167	iounmap(srom->reg_base);
	168
	169	return 0;
	170	}
	171
	172	#ifdef CONFIG_PM_SLEEP
	173	static void exynos_srom_save(void __iomem *base,
	174	struct exynos_srom_reg_dump *rd,
	175	unsigned int num_regs)
	176	{
	177	for (; num_regs > 0; --num_regs, ++rd)
	178	rd->value = readl(base + rd->offset);
	179	}
	180
	181	static void exynos_srom_restore(void __iomem *base,
	182	const struct exynos_srom_reg_dump *rd,
	183	unsigned int num_regs)
	184	{
	185	for (; num_regs > 0; --num_regs, ++rd)
	186	writel(rd->value, base + rd->offset);
	187	}
	188
	189	static int exynos_srom_suspend(struct device *dev)
	190	{
	191	struct exynos_srom *srom = dev_get_drvdata(dev);
	192
	193	exynos_srom_save(srom->reg_base, srom->reg_offset,
	194	ARRAY_SIZE(exynos_srom_offsets));
	195	return 0;
	196	}
	197
	198	static int exynos_srom_resume(struct device *dev)
	199	{
	200	struct exynos_srom *srom = dev_get_drvdata(dev);
	201
	202	exynos_srom_restore(srom->reg_base, srom->reg_offset,
	203	ARRAY_SIZE(exynos_srom_offsets));
	204	return 0;
	205	}
	206	#endif
	207
	208	static const struct of_device_id of_exynos_srom_ids[] = {
	209	{
	210	.compatible = "samsung,exynos4210-srom",
	211	},
	212	{},
	213	};
	214	MODULE_DEVICE_TABLE(of, of_exynos_srom_ids);
	215
	216	static SIMPLE_DEV_PM_OPS(exynos_srom_pm_ops, exynos_srom_suspend, exynos_srom_resume);
	217
	218	static struct platform_driver exynos_srom_driver = {
	219	.probe = exynos_srom_probe,
	220	.remove = exynos_srom_remove,
	221	.driver = {
	222	.name = "exynos-srom",
	223	.of_match_table = of_exynos_srom_ids,
224	.pm = &exynos_srom_pm_ops,
225	},
226	};
227	module_platform_driver(exynos_srom_driver);
228
229	MODULE_AUTHOR("Pankaj Dubey <pankaj.dubey@samsung.com>");
230	MODULE_DESCRIPTION("Exynos SROM Controller Driver");
231	MODULE_LICENSE("GPL");