| /* |
| * 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 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"); |