drivers/memory/ti-emif-pm.c - linux - Git at Google

 /*
  * TI AM33XX SRAM EMIF Driver
  *
  * Copyright (C) 2016-2017 Texas Instruments Inc.
  *	Dave Gerlach
  *
  * 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.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  */

 #include <linux/err.h>
 #include <linux/genalloc.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/sram.h>
 #include <linux/ti-emif-sram.h>

 #include "emif.h"

 #define TI_EMIF_SRAM_SYMBOL_OFFSET(sym) ((unsigned long)(sym) - \
 					 (unsigned long)&ti_emif_sram)

 #define EMIF_POWER_MGMT_WAIT_SELF_REFRESH_8192_CYCLES		0x00a0

 struct ti_emif_data {
 	phys_addr_t ti_emif_sram_phys;
 	phys_addr_t ti_emif_sram_data_phys;
 	unsigned long ti_emif_sram_virt;
 	unsigned long ti_emif_sram_data_virt;
 	struct gen_pool *sram_pool_code;
 	struct gen_pool	*sram_pool_data;
 	struct ti_emif_pm_data pm_data;
 	struct ti_emif_pm_functions pm_functions;
 };

 static struct ti_emif_data *emif_instance;

 static u32 sram_suspend_address(struct ti_emif_data *emif_data,
 				unsigned long addr)
 {
 	return (emif_data->ti_emif_sram_virt +
 		TI_EMIF_SRAM_SYMBOL_OFFSET(addr));
 }

 static phys_addr_t sram_resume_address(struct ti_emif_data *emif_data,
 				       unsigned long addr)
 {
 	return ((unsigned long)emif_data->ti_emif_sram_phys +
 		TI_EMIF_SRAM_SYMBOL_OFFSET(addr));
 }

 static void ti_emif_free_sram(struct ti_emif_data *emif_data)
 {
 	gen_pool_free(emif_data->sram_pool_code, emif_data->ti_emif_sram_virt,
 		      ti_emif_sram_sz);
 	gen_pool_free(emif_data->sram_pool_data,
 		      emif_data->ti_emif_sram_data_virt,
 		      sizeof(struct emif_regs_amx3));
 }

 static int ti_emif_alloc_sram(struct device *dev,
 			      struct ti_emif_data *emif_data)
 {
 	struct device_node *np = dev->of_node;
 	int ret;

 	emif_data->sram_pool_code = of_gen_pool_get(np, "sram", 0);
 	if (!emif_data->sram_pool_code) {
 		dev_err(dev, "Unable to get sram pool for ocmcram code\n");
 		return -ENODEV;
 	}

 	emif_data->ti_emif_sram_virt =
 			gen_pool_alloc(emif_data->sram_pool_code,
 				       ti_emif_sram_sz);
 	if (!emif_data->ti_emif_sram_virt) {
 		dev_err(dev, "Unable to allocate code memory from ocmcram\n");
 		return -ENOMEM;
 	}

 	/* Save physical address to calculate resume offset during pm init */
 	emif_data->ti_emif_sram_phys =
 			gen_pool_virt_to_phys(emif_data->sram_pool_code,
 					      emif_data->ti_emif_sram_virt);

 	/* Get sram pool for data section and allocate space */
 	emif_data->sram_pool_data = of_gen_pool_get(np, "sram", 1);
 	if (!emif_data->sram_pool_data) {
 		dev_err(dev, "Unable to get sram pool for ocmcram data\n");
 		ret = -ENODEV;
 		goto err_free_sram_code;
 	}

 	emif_data->ti_emif_sram_data_virt =
 				gen_pool_alloc(emif_data->sram_pool_data,
 					       sizeof(struct emif_regs_amx3));
 	if (!emif_data->ti_emif_sram_data_virt) {
 		dev_err(dev, "Unable to allocate data memory from ocmcram\n");
 		ret = -ENOMEM;
 		goto err_free_sram_code;
 	}

 	/* Save physical address to calculate resume offset during pm init */
 	emif_data->ti_emif_sram_data_phys =
 		gen_pool_virt_to_phys(emif_data->sram_pool_data,
 				      emif_data->ti_emif_sram_data_virt);
 	/*
 	 * These functions are called during suspend path while MMU is
 	 * still on so add virtual base to offset for absolute address
 	 */
 	emif_data->pm_functions.save_context =
 		sram_suspend_address(emif_data,
 				     (unsigned long)ti_emif_save_context);
 	emif_data->pm_functions.enter_sr =
 		sram_suspend_address(emif_data,
 				     (unsigned long)ti_emif_enter_sr);
 	emif_data->pm_functions.abort_sr =
 		sram_suspend_address(emif_data,
 				     (unsigned long)ti_emif_abort_sr);

 	/*
 	 * These are called during resume path when MMU is not enabled
 	 * so physical address is used instead
 	 */
 	emif_data->pm_functions.restore_context =
 		sram_resume_address(emif_data,
 				    (unsigned long)ti_emif_restore_context);
 	emif_data->pm_functions.exit_sr =
 		sram_resume_address(emif_data,
 				    (unsigned long)ti_emif_exit_sr);

 	emif_data->pm_data.regs_virt =
 		(struct emif_regs_amx3 *)emif_data->ti_emif_sram_data_virt;
 	emif_data->pm_data.regs_phys = emif_data->ti_emif_sram_data_phys;

 	return 0;

 err_free_sram_code:
 	gen_pool_free(emif_data->sram_pool_code, emif_data->ti_emif_sram_virt,
 		      ti_emif_sram_sz);
 	return ret;
 }

 static int ti_emif_push_sram(struct device *dev, struct ti_emif_data *emif_data)
 {
 	void *copy_addr;
 	u32 data_addr;

 	copy_addr = sram_exec_copy(emif_data->sram_pool_code,
 				   (void *)emif_data->ti_emif_sram_virt,
 				   &ti_emif_sram, ti_emif_sram_sz);
 	if (!copy_addr) {
 		dev_err(dev, "Cannot copy emif code to sram\n");
 		return -ENODEV;
 	}

 	data_addr = sram_suspend_address(emif_data,
 					 (unsigned long)&ti_emif_pm_sram_data);
 	copy_addr = sram_exec_copy(emif_data->sram_pool_code,
 				   (void *)data_addr,
 				   &emif_data->pm_data,
 				   sizeof(emif_data->pm_data));
 	if (!copy_addr) {
 		dev_err(dev, "Cannot copy emif data to code sram\n");
 		return -ENODEV;
 	}

 	return 0;
 }

 /*
  * Due to Usage Note 3.1.2 "DDR3: JEDEC Compliance for Maximum
  * Self-Refresh Command Limit" found in AM335x Silicon Errata
  * (Document SPRZ360F Revised November 2013) we must configure
  * the self refresh delay timer to 0xA (8192 cycles) to avoid
  * generating too many refresh command from the EMIF.
  */
 static void ti_emif_configure_sr_delay(struct ti_emif_data *emif_data)
 {
 	writel(EMIF_POWER_MGMT_WAIT_SELF_REFRESH_8192_CYCLES,
 	       (emif_data->pm_data.ti_emif_base_addr_virt +
 		EMIF_POWER_MANAGEMENT_CONTROL));

 	writel(EMIF_POWER_MGMT_WAIT_SELF_REFRESH_8192_CYCLES,
 	       (emif_data->pm_data.ti_emif_base_addr_virt +
 		EMIF_POWER_MANAGEMENT_CTRL_SHDW));
 }

 /**
  * ti_emif_copy_pm_function_table - copy mapping of pm funcs in sram
  * @sram_pool: pointer to struct gen_pool where dst resides
  * @dst: void * to address that table should be copied
  *
  * Returns 0 if success other error code if table is not available
  */
 int ti_emif_copy_pm_function_table(struct gen_pool *sram_pool, void *dst)
 {
 	void *copy_addr;

 	if (!emif_instance)
 		return -ENODEV;

 	copy_addr = sram_exec_copy(sram_pool, dst,
 				   &emif_instance->pm_functions,
 				   sizeof(emif_instance->pm_functions));
 	if (!copy_addr)
 		return -ENODEV;

 	return 0;
 }
 EXPORT_SYMBOL_GPL(ti_emif_copy_pm_function_table);

 /**
  * ti_emif_get_mem_type - return type for memory type in use
  *
  * Returns memory type value read from EMIF or error code if fails
  */
 int ti_emif_get_mem_type(void)
 {
 	unsigned long temp;

 	if (!emif_instance)
 		return -ENODEV;

 	temp = readl(emif_instance->pm_data.ti_emif_base_addr_virt +
 		     EMIF_SDRAM_CONFIG);

 	temp = (temp & SDRAM_TYPE_MASK) >> SDRAM_TYPE_SHIFT;
 	return temp;
 }
 EXPORT_SYMBOL_GPL(ti_emif_get_mem_type);

 static const struct of_device_id ti_emif_of_match[] = {
 	{ .compatible = "ti,emif-am3352", .data =
 					(void *)EMIF_SRAM_AM33_REG_LAYOUT, },
 	{ .compatible = "ti,emif-am4372", .data =
 					(void *)EMIF_SRAM_AM43_REG_LAYOUT, },
 	{},
 };
 MODULE_DEVICE_TABLE(of, ti_emif_of_match);

 static int ti_emif_probe(struct platform_device *pdev)
 {
 	int ret;
 	struct resource *res;
 	struct device *dev = &pdev->dev;
 	const struct of_device_id *match;
 	struct ti_emif_data *emif_data;

 	emif_data = devm_kzalloc(dev, sizeof(*emif_data), GFP_KERNEL);
 	if (!emif_data)
 		return -ENOMEM;

 	match = of_match_device(ti_emif_of_match, &pdev->dev);
 	if (!match)
 		return -ENODEV;

 	emif_data->pm_data.ti_emif_sram_config = (unsigned long)match->data;

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	emif_data->pm_data.ti_emif_base_addr_virt = devm_ioremap_resource(dev,
 									  res);
 	if (IS_ERR(emif_data->pm_data.ti_emif_base_addr_virt)) {
 		dev_err(dev, "could not ioremap emif mem\n");
 		ret = PTR_ERR(emif_data->pm_data.ti_emif_base_addr_virt);
 		return ret;
 	}

 	emif_data->pm_data.ti_emif_base_addr_phys = res->start;

 	ti_emif_configure_sr_delay(emif_data);

 	ret = ti_emif_alloc_sram(dev, emif_data);
 	if (ret)
 		return ret;

 	ret = ti_emif_push_sram(dev, emif_data);
 	if (ret)
 		goto fail_free_sram;

 	emif_instance = emif_data;

 	return 0;

 fail_free_sram:
 	ti_emif_free_sram(emif_data);

 	return ret;
 }

 static int ti_emif_remove(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct ti_emif_data *emif_data = emif_instance;

 	emif_instance = NULL;

 	ti_emif_free_sram(emif_data);

 	return 0;
 }

 static struct platform_driver ti_emif_driver = {
 	.probe = ti_emif_probe,
 	.remove = ti_emif_remove,
 	.driver = {
 		.name = KBUILD_MODNAME,
 		.of_match_table = of_match_ptr(ti_emif_of_match),
 	},
 };
 module_platform_driver(ti_emif_driver);

 MODULE_AUTHOR("Dave Gerlach <d-gerlach@ti.com>");
 MODULE_DESCRIPTION("Texas Instruments SRAM EMIF driver");
 MODULE_LICENSE("GPL v2");
	/*
	* TI AM33XX SRAM EMIF Driver
	*
	* Copyright (C) 2016-2017 Texas Instruments Inc.
	* Dave Gerlach
	*
	* 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.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*/

	#include <linux/err.h>
	#include <linux/genalloc.h>
	#include <linux/io.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/of_platform.h>
	#include <linux/platform_device.h>
	#include <linux/sram.h>
	#include <linux/ti-emif-sram.h>

	#include "emif.h"

	#define TI_EMIF_SRAM_SYMBOL_OFFSET(sym) ((unsigned long)(sym) - \
	(unsigned long)&ti_emif_sram)

	#define EMIF_POWER_MGMT_WAIT_SELF_REFRESH_8192_CYCLES 0x00a0

	struct ti_emif_data {
	phys_addr_t ti_emif_sram_phys;
	phys_addr_t ti_emif_sram_data_phys;
	unsigned long ti_emif_sram_virt;
	unsigned long ti_emif_sram_data_virt;
	struct gen_pool *sram_pool_code;
	struct gen_pool *sram_pool_data;
	struct ti_emif_pm_data pm_data;
	struct ti_emif_pm_functions pm_functions;
	};

	static struct ti_emif_data *emif_instance;

	static u32 sram_suspend_address(struct ti_emif_data *emif_data,
	unsigned long addr)
	{
	return (emif_data->ti_emif_sram_virt +
	TI_EMIF_SRAM_SYMBOL_OFFSET(addr));
	}

	static phys_addr_t sram_resume_address(struct ti_emif_data *emif_data,
	unsigned long addr)
	{
	return ((unsigned long)emif_data->ti_emif_sram_phys +
	TI_EMIF_SRAM_SYMBOL_OFFSET(addr));
	}

	static void ti_emif_free_sram(struct ti_emif_data *emif_data)
	{
	gen_pool_free(emif_data->sram_pool_code, emif_data->ti_emif_sram_virt,
	ti_emif_sram_sz);
	gen_pool_free(emif_data->sram_pool_data,
	emif_data->ti_emif_sram_data_virt,
	sizeof(struct emif_regs_amx3));
	}

	static int ti_emif_alloc_sram(struct device *dev,
	struct ti_emif_data *emif_data)
	{
	struct device_node *np = dev->of_node;
	int ret;

	emif_data->sram_pool_code = of_gen_pool_get(np, "sram", 0);
	if (!emif_data->sram_pool_code) {
	dev_err(dev, "Unable to get sram pool for ocmcram code\n");
	return -ENODEV;
	}

	emif_data->ti_emif_sram_virt =
	gen_pool_alloc(emif_data->sram_pool_code,
	ti_emif_sram_sz);
	if (!emif_data->ti_emif_sram_virt) {
	dev_err(dev, "Unable to allocate code memory from ocmcram\n");
	return -ENOMEM;
	}

	/* Save physical address to calculate resume offset during pm init */
	emif_data->ti_emif_sram_phys =
	gen_pool_virt_to_phys(emif_data->sram_pool_code,
	emif_data->ti_emif_sram_virt);

	/* Get sram pool for data section and allocate space */
	emif_data->sram_pool_data = of_gen_pool_get(np, "sram", 1);
	if (!emif_data->sram_pool_data) {
	dev_err(dev, "Unable to get sram pool for ocmcram data\n");
	ret = -ENODEV;
	goto err_free_sram_code;
	}

	emif_data->ti_emif_sram_data_virt =
	gen_pool_alloc(emif_data->sram_pool_data,
	sizeof(struct emif_regs_amx3));
	if (!emif_data->ti_emif_sram_data_virt) {
	dev_err(dev, "Unable to allocate data memory from ocmcram\n");
	ret = -ENOMEM;
	goto err_free_sram_code;
	}

	/* Save physical address to calculate resume offset during pm init */
	emif_data->ti_emif_sram_data_phys =
	gen_pool_virt_to_phys(emif_data->sram_pool_data,
	emif_data->ti_emif_sram_data_virt);
	/*
	* These functions are called during suspend path while MMU is
	* still on so add virtual base to offset for absolute address
	*/
	emif_data->pm_functions.save_context =
	sram_suspend_address(emif_data,
	(unsigned long)ti_emif_save_context);
	emif_data->pm_functions.enter_sr =
	sram_suspend_address(emif_data,
	(unsigned long)ti_emif_enter_sr);
	emif_data->pm_functions.abort_sr =
	sram_suspend_address(emif_data,
	(unsigned long)ti_emif_abort_sr);

	/*
	* These are called during resume path when MMU is not enabled
	* so physical address is used instead
	*/
	emif_data->pm_functions.restore_context =
	sram_resume_address(emif_data,
	(unsigned long)ti_emif_restore_context);
	emif_data->pm_functions.exit_sr =
	sram_resume_address(emif_data,
	(unsigned long)ti_emif_exit_sr);

	emif_data->pm_data.regs_virt =
	(struct emif_regs_amx3 *)emif_data->ti_emif_sram_data_virt;
	emif_data->pm_data.regs_phys = emif_data->ti_emif_sram_data_phys;

	return 0;

	err_free_sram_code:
	gen_pool_free(emif_data->sram_pool_code, emif_data->ti_emif_sram_virt,
	ti_emif_sram_sz);
	return ret;
	}

	static int ti_emif_push_sram(struct device dev, struct ti_emif_data emif_data)
	{
	void *copy_addr;
	u32 data_addr;

	copy_addr = sram_exec_copy(emif_data->sram_pool_code,
	(void *)emif_data->ti_emif_sram_virt,
	&ti_emif_sram, ti_emif_sram_sz);
	if (!copy_addr) {
	dev_err(dev, "Cannot copy emif code to sram\n");
	return -ENODEV;
	}

	data_addr = sram_suspend_address(emif_data,
	(unsigned long)&ti_emif_pm_sram_data);
	copy_addr = sram_exec_copy(emif_data->sram_pool_code,
	(void *)data_addr,
	&emif_data->pm_data,
	sizeof(emif_data->pm_data));
	if (!copy_addr) {
	dev_err(dev, "Cannot copy emif data to code sram\n");
	return -ENODEV;
	}

	return 0;
	}

	/*
	* Due to Usage Note 3.1.2 "DDR3: JEDEC Compliance for Maximum
	* Self-Refresh Command Limit" found in AM335x Silicon Errata
	* (Document SPRZ360F Revised November 2013) we must configure
	* the self refresh delay timer to 0xA (8192 cycles) to avoid
	* generating too many refresh command from the EMIF.
	*/
	static void ti_emif_configure_sr_delay(struct ti_emif_data *emif_data)
	{
	writel(EMIF_POWER_MGMT_WAIT_SELF_REFRESH_8192_CYCLES,
	(emif_data->pm_data.ti_emif_base_addr_virt +
	EMIF_POWER_MANAGEMENT_CONTROL));

	writel(EMIF_POWER_MGMT_WAIT_SELF_REFRESH_8192_CYCLES,
	(emif_data->pm_data.ti_emif_base_addr_virt +
	EMIF_POWER_MANAGEMENT_CTRL_SHDW));
	}

	/**
	* ti_emif_copy_pm_function_table - copy mapping of pm funcs in sram
	* @sram_pool: pointer to struct gen_pool where dst resides
	* @dst: void * to address that table should be copied
	*
	* Returns 0 if success other error code if table is not available
	*/
	int ti_emif_copy_pm_function_table(struct gen_pool sram_pool, void dst)
	{
	void *copy_addr;

	if (!emif_instance)
	return -ENODEV;

	copy_addr = sram_exec_copy(sram_pool, dst,
	&emif_instance->pm_functions,
	sizeof(emif_instance->pm_functions));
	if (!copy_addr)
	return -ENODEV;

	return 0;
	}
	EXPORT_SYMBOL_GPL(ti_emif_copy_pm_function_table);

	/**
	* ti_emif_get_mem_type - return type for memory type in use
	*
	* Returns memory type value read from EMIF or error code if fails
	*/
	int ti_emif_get_mem_type(void)
	{
	unsigned long temp;

	if (!emif_instance)
	return -ENODEV;

	temp = readl(emif_instance->pm_data.ti_emif_base_addr_virt +
	EMIF_SDRAM_CONFIG);

	temp = (temp & SDRAM_TYPE_MASK) >> SDRAM_TYPE_SHIFT;
	return temp;
	}
	EXPORT_SYMBOL_GPL(ti_emif_get_mem_type);

	static const struct of_device_id ti_emif_of_match[] = {
	{ .compatible = "ti,emif-am3352", .data =
	(void *)EMIF_SRAM_AM33_REG_LAYOUT, },
	{ .compatible = "ti,emif-am4372", .data =
	(void *)EMIF_SRAM_AM43_REG_LAYOUT, },
	{},
	};
	MODULE_DEVICE_TABLE(of, ti_emif_of_match);

	static int ti_emif_probe(struct platform_device *pdev)
	{
	int ret;
	struct resource *res;
	struct device *dev = &pdev->dev;
	const struct of_device_id *match;
	struct ti_emif_data *emif_data;

	emif_data = devm_kzalloc(dev, sizeof(*emif_data), GFP_KERNEL);
	if (!emif_data)
	return -ENOMEM;

	match = of_match_device(ti_emif_of_match, &pdev->dev);
	if (!match)
	return -ENODEV;

	emif_data->pm_data.ti_emif_sram_config = (unsigned long)match->data;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	emif_data->pm_data.ti_emif_base_addr_virt = devm_ioremap_resource(dev,
	res);
	if (IS_ERR(emif_data->pm_data.ti_emif_base_addr_virt)) {
	dev_err(dev, "could not ioremap emif mem\n");
	ret = PTR_ERR(emif_data->pm_data.ti_emif_base_addr_virt);
	return ret;
	}

	emif_data->pm_data.ti_emif_base_addr_phys = res->start;

	ti_emif_configure_sr_delay(emif_data);

	ret = ti_emif_alloc_sram(dev, emif_data);
	if (ret)
	return ret;

	ret = ti_emif_push_sram(dev, emif_data);
	if (ret)
	goto fail_free_sram;

	emif_instance = emif_data;

	return 0;

	fail_free_sram:
	ti_emif_free_sram(emif_data);

	return ret;
	}

	static int ti_emif_remove(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	struct ti_emif_data *emif_data = emif_instance;

	emif_instance = NULL;

	ti_emif_free_sram(emif_data);

	return 0;
	}

	static struct platform_driver ti_emif_driver = {
	.probe = ti_emif_probe,
	.remove = ti_emif_remove,
	.driver = {
	.name = KBUILD_MODNAME,
	.of_match_table = of_match_ptr(ti_emif_of_match),
	},
	};
	module_platform_driver(ti_emif_driver);

	MODULE_AUTHOR("Dave Gerlach <d-gerlach@ti.com>");
	MODULE_DESCRIPTION("Texas Instruments SRAM EMIF driver");
	MODULE_LICENSE("GPL v2");