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-rw-r--r--drivers/memory/ti-emif-pm.c324
1 files changed, 324 insertions, 0 deletions
diff --git a/drivers/memory/ti-emif-pm.c b/drivers/memory/ti-emif-pm.c
new file mode 100644
index 000000000000..62a86c4bcd0b
--- /dev/null
+++ b/drivers/memory/ti-emif-pm.c
@@ -0,0 +1,324 @@
+/*
+ * 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");