diff options
Diffstat (limited to 'drivers/mtd/devices/elm.c')
| -rw-r--r-- | drivers/mtd/devices/elm.c | 218 |
1 files changed, 193 insertions, 25 deletions
diff --git a/drivers/mtd/devices/elm.c b/drivers/mtd/devices/elm.c index dccef9fdc1f..b4f61c7fc16 100644 --- a/drivers/mtd/devices/elm.c +++ b/drivers/mtd/devices/elm.c @@ -15,19 +15,28 @@ * */ +#define DRIVER_NAME "omap-elm" + #include <linux/platform_device.h> #include <linux/module.h> #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 +65,29 @@ #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; + int ecc_steps; + int ecc_syndrome_size; }; static LIST_HEAD(elm_devices); @@ -81,7 +107,8 @@ static u32 elm_read_reg(struct elm_info *info, int offset) * @dev: ELM device * @bch_type: Type of BCH ecc */ -int elm_config(struct device *dev, enum bch_ecc bch_type) +int elm_config(struct device *dev, enum bch_ecc bch_type, + int ecc_steps, int ecc_step_size, int ecc_syndrome_size) { u32 reg_val; struct elm_info *info = dev_get_drvdata(dev); @@ -90,10 +117,22 @@ int elm_config(struct device *dev, enum bch_ecc bch_type) dev_err(dev, "Unable to configure elm - device not probed?\n"); return -ENODEV; } + /* ELM cannot detect ECC errors for chunks > 1KB */ + if (ecc_step_size > ((ELM_ECC_SIZE + 1) / 2)) { + dev_err(dev, "unsupported config ecc-size=%d\n", ecc_step_size); + return -EINVAL; + } + /* ELM support 8 error syndrome process */ + if (ecc_steps > ERROR_VECTOR_MAX) { + dev_err(dev, "unsupported config ecc-step=%d\n", ecc_steps); + return -EINVAL; + } reg_val = (bch_type & ECC_BCH_LEVEL_MASK) | (ELM_ECC_SIZE << 16); elm_write_reg(info, ELM_LOCATION_CONFIG, reg_val); - info->bch_type = bch_type; + info->bch_type = bch_type; + info->ecc_steps = ecc_steps; + info->ecc_syndrome_size = ecc_syndrome_size; return 0; } @@ -135,17 +174,15 @@ static void elm_load_syndrome(struct elm_info *info, int i, offset; u32 val; - for (i = 0; i < ERROR_VECTOR_MAX; i++) { + for (i = 0; i < info->ecc_steps; i++) { /* Check error reported */ if (err_vec[i].error_reported) { elm_configure_page_mode(info, i, true); offset = ELM_SYNDROME_FRAGMENT_0 + SYNDROME_FRAGMENT_REG_SIZE * i; - - /* BCH8 */ - if (info->bch_type) { - + switch (info->bch_type) { + case BCH8_ECC: /* syndrome fragment 0 = ecc[9-12B] */ val = cpu_to_be32(*(u32 *) &ecc[9]); elm_write_reg(info, offset, val); @@ -164,7 +201,8 @@ static void elm_load_syndrome(struct elm_info *info, offset += 4; val = ecc[0]; elm_write_reg(info, offset, val); - } else { + break; + case BCH4_ECC: /* syndrome fragment 0 = ecc[20-52b] bits */ val = (cpu_to_be32(*(u32 *) &ecc[3]) >> 4) | ((ecc[2] & 0xf) << 28); @@ -174,11 +212,36 @@ static void elm_load_syndrome(struct elm_info *info, offset += 4; val = cpu_to_be32(*(u32 *) &ecc[0]) >> 12; elm_write_reg(info, offset, val); + break; + case BCH16_ECC: + val = cpu_to_be32(*(u32 *) &ecc[22]); + elm_write_reg(info, offset, val); + offset += 4; + val = cpu_to_be32(*(u32 *) &ecc[18]); + elm_write_reg(info, offset, val); + offset += 4; + val = cpu_to_be32(*(u32 *) &ecc[14]); + elm_write_reg(info, offset, val); + offset += 4; + val = cpu_to_be32(*(u32 *) &ecc[10]); + elm_write_reg(info, offset, val); + offset += 4; + val = cpu_to_be32(*(u32 *) &ecc[6]); + elm_write_reg(info, offset, val); + offset += 4; + val = cpu_to_be32(*(u32 *) &ecc[2]); + elm_write_reg(info, offset, val); + offset += 4; + val = cpu_to_be32(*(u32 *) &ecc[0]) >> 16; + elm_write_reg(info, offset, val); + break; + default: + pr_err("invalid config bch_type\n"); } } /* Update ecc pointer with ecc byte size */ - ecc += info->bch_type ? BCH8_SIZE : BCH4_SIZE; + ecc += info->ecc_syndrome_size; } } @@ -201,7 +264,7 @@ static void elm_start_processing(struct elm_info *info, * Set syndrome vector valid, so that ELM module * will process it for vectors error is reported */ - for (i = 0; i < ERROR_VECTOR_MAX; i++) { + for (i = 0; i < info->ecc_steps; i++) { if (err_vec[i].error_reported) { offset = ELM_SYNDROME_FRAGMENT_6 + SYNDROME_FRAGMENT_REG_SIZE * i; @@ -230,7 +293,7 @@ static void elm_error_correction(struct elm_info *info, int offset; u32 reg_val; - for (i = 0; i < ERROR_VECTOR_MAX; i++) { + for (i = 0; i < info->ecc_steps; i++) { /* Check error reported */ if (err_vec[i].error_reported) { @@ -332,10 +395,8 @@ static int elm_probe(struct platform_device *pdev) struct elm_info *info; info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL); - if (!info) { - dev_err(&pdev->dev, "failed to allocate memory\n"); + if (!info) return -ENOMEM; - } info->dev = &pdev->dev; @@ -346,14 +407,9 @@ 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); @@ -363,7 +419,7 @@ static int elm_probe(struct platform_device *pdev) } pm_runtime_enable(&pdev->dev); - if (pm_runtime_get_sync(&pdev->dev)) { + if (pm_runtime_get_sync(&pdev->dev) < 0) { ret = -EINVAL; pm_runtime_disable(&pdev->dev); dev_err(&pdev->dev, "can't enable clock\n"); @@ -381,10 +437,121 @@ 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; } +#ifdef CONFIG_PM_SLEEP +/** + * 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 BCH16_ECC: + regs->elm_syndrome_fragment_6[i] = elm_read_reg(info, + ELM_SYNDROME_FRAGMENT_6 + offset); + regs->elm_syndrome_fragment_5[i] = elm_read_reg(info, + ELM_SYNDROME_FRAGMENT_5 + offset); + regs->elm_syndrome_fragment_4[i] = elm_read_reg(info, + ELM_SYNDROME_FRAGMENT_4 + offset); + 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); + break; + 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 BCH16_ECC: + elm_write_reg(info, ELM_SYNDROME_FRAGMENT_6 + offset, + regs->elm_syndrome_fragment_6[i]); + elm_write_reg(info, ELM_SYNDROME_FRAGMENT_5 + offset, + regs->elm_syndrome_fragment_5[i]); + elm_write_reg(info, ELM_SYNDROME_FRAGMENT_4 + offset, + regs->elm_syndrome_fragment_4[i]); + 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]); + break; + 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; +} +#endif + +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" }, @@ -395,9 +562,10 @@ MODULE_DEVICE_TABLE(of, elm_of_match); static struct platform_driver elm_driver = { .driver = { - .name = "elm", + .name = DRIVER_NAME, .owner = THIS_MODULE, .of_match_table = of_match_ptr(elm_of_match), + .pm = &elm_pm_ops, }, .probe = elm_probe, .remove = elm_remove, |