diff options
Diffstat (limited to 'drivers/mtd/devices/elm.c')
| -rw-r--r-- | drivers/mtd/devices/elm.c | 129 |
1 files changed, 120 insertions, 9 deletions
diff --git a/drivers/mtd/devices/elm.c b/drivers/mtd/devices/elm.c index dccef9fdc1f2..d1dd6a33a050 100644 --- a/drivers/mtd/devices/elm.c +++ b/drivers/mtd/devices/elm.c @@ -20,14 +20,21 @@ #include <linux/interrupt.h> #include <linux/io.h> #include <linux/of.h> +#include <linux/sched.h> #include <linux/pm_runtime.h> #include <linux/platform_data/elm.h> +#define ELM_SYSCONFIG 0x010 #define ELM_IRQSTATUS 0x018 #define ELM_IRQENABLE 0x01c #define ELM_LOCATION_CONFIG 0x020 #define ELM_PAGE_CTRL 0x080 #define ELM_SYNDROME_FRAGMENT_0 0x400 +#define ELM_SYNDROME_FRAGMENT_1 0x404 +#define ELM_SYNDROME_FRAGMENT_2 0x408 +#define ELM_SYNDROME_FRAGMENT_3 0x40c +#define ELM_SYNDROME_FRAGMENT_4 0x410 +#define ELM_SYNDROME_FRAGMENT_5 0x414 #define ELM_SYNDROME_FRAGMENT_6 0x418 #define ELM_LOCATION_STATUS 0x800 #define ELM_ERROR_LOCATION_0 0x880 @@ -56,12 +63,27 @@ #define SYNDROME_FRAGMENT_REG_SIZE 0x40 #define ERROR_LOCATION_SIZE 0x100 +struct elm_registers { + u32 elm_irqenable; + u32 elm_sysconfig; + u32 elm_location_config; + u32 elm_page_ctrl; + u32 elm_syndrome_fragment_6[ERROR_VECTOR_MAX]; + u32 elm_syndrome_fragment_5[ERROR_VECTOR_MAX]; + u32 elm_syndrome_fragment_4[ERROR_VECTOR_MAX]; + u32 elm_syndrome_fragment_3[ERROR_VECTOR_MAX]; + u32 elm_syndrome_fragment_2[ERROR_VECTOR_MAX]; + u32 elm_syndrome_fragment_1[ERROR_VECTOR_MAX]; + u32 elm_syndrome_fragment_0[ERROR_VECTOR_MAX]; +}; + struct elm_info { struct device *dev; void __iomem *elm_base; struct completion elm_completion; struct list_head list; enum bch_ecc bch_type; + struct elm_registers elm_regs; }; static LIST_HEAD(elm_devices); @@ -346,14 +368,9 @@ static int elm_probe(struct platform_device *pdev) } res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!res) { - dev_err(&pdev->dev, "no memory resource defined\n"); - return -ENODEV; - } - - info->elm_base = devm_request_and_ioremap(&pdev->dev, res); - if (!info->elm_base) - return -EADDRNOTAVAIL; + info->elm_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(info->elm_base)) + return PTR_ERR(info->elm_base); ret = devm_request_irq(&pdev->dev, irq->start, elm_isr, 0, pdev->name, info); @@ -381,10 +398,103 @@ static int elm_remove(struct platform_device *pdev) { pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev); - platform_set_drvdata(pdev, NULL); return 0; } +/** + * elm_context_save + * saves ELM configurations to preserve them across Hardware powered-down + */ +static int elm_context_save(struct elm_info *info) +{ + struct elm_registers *regs = &info->elm_regs; + enum bch_ecc bch_type = info->bch_type; + u32 offset = 0, i; + + regs->elm_irqenable = elm_read_reg(info, ELM_IRQENABLE); + regs->elm_sysconfig = elm_read_reg(info, ELM_SYSCONFIG); + regs->elm_location_config = elm_read_reg(info, ELM_LOCATION_CONFIG); + regs->elm_page_ctrl = elm_read_reg(info, ELM_PAGE_CTRL); + for (i = 0; i < ERROR_VECTOR_MAX; i++) { + offset = i * SYNDROME_FRAGMENT_REG_SIZE; + switch (bch_type) { + case BCH8_ECC: + regs->elm_syndrome_fragment_3[i] = elm_read_reg(info, + ELM_SYNDROME_FRAGMENT_3 + offset); + regs->elm_syndrome_fragment_2[i] = elm_read_reg(info, + ELM_SYNDROME_FRAGMENT_2 + offset); + case BCH4_ECC: + regs->elm_syndrome_fragment_1[i] = elm_read_reg(info, + ELM_SYNDROME_FRAGMENT_1 + offset); + regs->elm_syndrome_fragment_0[i] = elm_read_reg(info, + ELM_SYNDROME_FRAGMENT_0 + offset); + default: + return -EINVAL; + } + /* ELM SYNDROME_VALID bit in SYNDROME_FRAGMENT_6[] needs + * to be saved for all BCH schemes*/ + regs->elm_syndrome_fragment_6[i] = elm_read_reg(info, + ELM_SYNDROME_FRAGMENT_6 + offset); + } + return 0; +} + +/** + * elm_context_restore + * writes configurations saved duing power-down back into ELM registers + */ +static int elm_context_restore(struct elm_info *info) +{ + struct elm_registers *regs = &info->elm_regs; + enum bch_ecc bch_type = info->bch_type; + u32 offset = 0, i; + + elm_write_reg(info, ELM_IRQENABLE, regs->elm_irqenable); + elm_write_reg(info, ELM_SYSCONFIG, regs->elm_sysconfig); + elm_write_reg(info, ELM_LOCATION_CONFIG, regs->elm_location_config); + elm_write_reg(info, ELM_PAGE_CTRL, regs->elm_page_ctrl); + for (i = 0; i < ERROR_VECTOR_MAX; i++) { + offset = i * SYNDROME_FRAGMENT_REG_SIZE; + switch (bch_type) { + case BCH8_ECC: + elm_write_reg(info, ELM_SYNDROME_FRAGMENT_3 + offset, + regs->elm_syndrome_fragment_3[i]); + elm_write_reg(info, ELM_SYNDROME_FRAGMENT_2 + offset, + regs->elm_syndrome_fragment_2[i]); + case BCH4_ECC: + elm_write_reg(info, ELM_SYNDROME_FRAGMENT_1 + offset, + regs->elm_syndrome_fragment_1[i]); + elm_write_reg(info, ELM_SYNDROME_FRAGMENT_0 + offset, + regs->elm_syndrome_fragment_0[i]); + default: + return -EINVAL; + } + /* ELM_SYNDROME_VALID bit to be set in last to trigger FSM */ + elm_write_reg(info, ELM_SYNDROME_FRAGMENT_6 + offset, + regs->elm_syndrome_fragment_6[i] & + ELM_SYNDROME_VALID); + } + return 0; +} + +static int elm_suspend(struct device *dev) +{ + struct elm_info *info = dev_get_drvdata(dev); + elm_context_save(info); + pm_runtime_put_sync(dev); + return 0; +} + +static int elm_resume(struct device *dev) +{ + struct elm_info *info = dev_get_drvdata(dev); + pm_runtime_get_sync(dev); + elm_context_restore(info); + return 0; +} + +static SIMPLE_DEV_PM_OPS(elm_pm_ops, elm_suspend, elm_resume); + #ifdef CONFIG_OF static const struct of_device_id elm_of_match[] = { { .compatible = "ti,am3352-elm" }, @@ -398,6 +508,7 @@ static struct platform_driver elm_driver = { .name = "elm", .owner = THIS_MODULE, .of_match_table = of_match_ptr(elm_of_match), + .pm = &elm_pm_ops, }, .probe = elm_probe, .remove = elm_remove, |