summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--drivers/mtd/nand/Kconfig10
-rw-r--r--drivers/mtd/nand/Makefile1
-rw-r--r--drivers/mtd/nand/omap_elm.c413
-rw-r--r--include/platform_data/elm.h53
4 files changed, 477 insertions, 0 deletions
diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index 2b4a478a03..fadfe1f99b 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -90,6 +90,16 @@ config NAND_OMAP_GPMC
Support for NAND flash using GPMC. GPMC is a common memory
interface found on Texas Instrument's OMAP platforms
+config MTD_NAND_OMAP_ELM
+ bool "Support for ELM (Error Location Module) on OMAP platforms"
+ depends on NAND_OMAP_GPMC
+ help
+ This config enables the ELM hardware engine, which can be used to
+ locate and correct errors when using BCH ECC scheme. This offloads
+ the cpu from doing ECC error searching and correction. However some
+ legacy OMAP families like OMAP2xxx, OMAP3xxx do not have ELM engine
+ so this is optional for them.
+
config NAND_ORION
bool
prompt "Marvell Orion NAND driver"
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index 6088512745..a4066ba778 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_MTD_NAND_NOMADIK) += nomadik_nand.o
obj-$(CONFIG_NAND_IMX) += nand_imx.o
obj-$(CONFIG_NAND_IMX_BBM) += nand_imx_bbm.o
obj-$(CONFIG_NAND_OMAP_GPMC) += nand_omap_gpmc.o nand_omap_bch_decoder.o
+obj-$(CONFIG_MTD_NAND_OMAP_ELM) += omap_elm.o
obj-$(CONFIG_NAND_ORION) += nand_orion.o
obj-$(CONFIG_NAND_MRVL_NFC) += nand_mrvl_nfc.o
obj-$(CONFIG_NAND_ATMEL) += atmel_nand.o
diff --git a/drivers/mtd/nand/omap_elm.c b/drivers/mtd/nand/omap_elm.c
new file mode 100644
index 0000000000..583235fc78
--- /dev/null
+++ b/drivers/mtd/nand/omap_elm.c
@@ -0,0 +1,413 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Error Location Module
+ *
+ * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
+ */
+
+#define DRIVER_NAME "omap-elm"
+
+#include <common.h>
+#include <driver.h>
+#include <init.h>
+#include <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
+
+/* ELM Interrupt Status Register */
+#define INTR_STATUS_PAGE_VALID BIT(8)
+
+/* ELM Interrupt Enable Register */
+#define INTR_EN_PAGE_MASK BIT(8)
+
+/* ELM Location Configuration Register */
+#define ECC_BCH_LEVEL_MASK 0x3
+
+/* ELM syndrome */
+#define ELM_SYNDROME_VALID BIT(16)
+
+/* ELM_LOCATION_STATUS Register */
+#define ECC_CORRECTABLE_MASK BIT(8)
+#define ECC_NB_ERRORS_MASK 0x1f
+
+/* ELM_ERROR_LOCATION_0-15 Registers */
+#define ECC_ERROR_LOCATION_MASK 0x1fff
+
+#define ELM_ECC_SIZE 0x7ff
+
+#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_d *dev;
+ void __iomem *elm_base;
+ struct list_head list;
+ enum bch_ecc bch_type;
+ struct elm_registers elm_regs;
+ int ecc_steps;
+ int ecc_syndrome_size;
+};
+
+static struct elm_info *ginfo;
+
+static void elm_write_reg(struct elm_info *info, int offset, u32 val)
+{
+ writel(val, info->elm_base + offset);
+}
+
+static u32 elm_read_reg(struct elm_info *info, int offset)
+{
+ return readl(info->elm_base + offset);
+}
+
+/**
+ * elm_config - Configure ELM module
+ * @dev: ELM device
+ * @bch_type: Type of BCH ecc
+ */
+int elm_config(enum bch_ecc bch_type, int ecc_steps, int ecc_step_size,
+ int ecc_syndrome_size)
+{
+ struct elm_info *info = ginfo;
+ u32 reg_val;
+
+ if (!info)
+ return -ENODEV;
+ /* ELM cannot detect ECC errors for chunks > 1KB */
+ if (ecc_step_size > ((ELM_ECC_SIZE + 1) / 2)) {
+ dev_err(info->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(info->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->ecc_steps = ecc_steps;
+ info->ecc_syndrome_size = ecc_syndrome_size;
+
+ return 0;
+}
+
+/**
+ * elm_configure_page_mode - Enable/Disable page mode
+ * @info: elm info
+ * @index: index number of syndrome fragment vector
+ * @enable: enable/disable flag for page mode
+ *
+ * Enable page mode for syndrome fragment index
+ */
+static void elm_configure_page_mode(struct elm_info *info, int index,
+ bool enable)
+{
+ u32 reg_val;
+
+ reg_val = elm_read_reg(info, ELM_PAGE_CTRL);
+ if (enable)
+ reg_val |= BIT(index); /* enable page mode */
+ else
+ reg_val &= ~BIT(index); /* disable page mode */
+
+ elm_write_reg(info, ELM_PAGE_CTRL, reg_val);
+}
+
+/**
+ * elm_load_syndrome - Load ELM syndrome reg
+ * @info: elm info
+ * @err_vec: elm error vectors
+ * @ecc: buffer with calculated ecc
+ *
+ * Load syndrome fragment registers with calculated ecc in reverse order.
+ */
+static void elm_load_syndrome(struct elm_info *info,
+ struct elm_errorvec *err_vec, u8 *ecc)
+{
+ int i, offset;
+ u32 val;
+
+ 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;
+ 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);
+
+ /* syndrome fragment 1 = ecc[5-8B] */
+ offset += 4;
+ val = cpu_to_be32(*(u32 *) &ecc[5]);
+ elm_write_reg(info, offset, val);
+
+ /* syndrome fragment 2 = ecc[1-4B] */
+ offset += 4;
+ val = cpu_to_be32(*(u32 *) &ecc[1]);
+ elm_write_reg(info, offset, val);
+
+ /* syndrome fragment 3 = ecc[0B] */
+ offset += 4;
+ val = ecc[0];
+ elm_write_reg(info, offset, val);
+ break;
+ case BCH4_ECC:
+ /* syndrome fragment 0 = ecc[20-52b] bits */
+ val = (cpu_to_be32(*(u32 *) &ecc[3]) >> 4) |
+ ((ecc[2] & 0xf) << 28);
+ elm_write_reg(info, offset, val);
+
+ /* syndrome fragment 1 = ecc[0-20b] bits */
+ 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->ecc_syndrome_size;
+ }
+}
+
+/**
+ * elm_start_processing - start elm syndrome processing
+ * @info: elm info
+ * @err_vec: elm error vectors
+ *
+ * Set syndrome valid bit for syndrome fragment registers for which
+ * elm syndrome fragment registers are loaded. This enables elm module
+ * to start processing syndrome vectors.
+ */
+static void elm_start_processing(struct elm_info *info,
+ struct elm_errorvec *err_vec)
+{
+ int i, offset;
+ u32 reg_val;
+
+ /*
+ * Set syndrome vector valid, so that ELM module
+ * will process it for vectors error is reported
+ */
+ for (i = 0; i < info->ecc_steps; i++) {
+ if (err_vec[i].error_reported) {
+ offset = ELM_SYNDROME_FRAGMENT_6 +
+ SYNDROME_FRAGMENT_REG_SIZE * i;
+ reg_val = elm_read_reg(info, offset);
+ reg_val |= ELM_SYNDROME_VALID;
+ elm_write_reg(info, offset, reg_val);
+ }
+ }
+}
+
+/**
+ * elm_error_correction - locate correctable error position
+ * @info: elm info
+ * @err_vec: elm error vectors
+ *
+ * On completion of processing by elm module, error location status
+ * register updated with correctable/uncorrectable error information.
+ * In case of correctable errors, number of errors located from
+ * elm location status register & read the positions from
+ * elm error location register.
+ */
+static void elm_error_correction(struct elm_info *info,
+ struct elm_errorvec *err_vec)
+{
+ int i, j, errors = 0;
+ int offset;
+ u32 reg_val;
+
+ for (i = 0; i < info->ecc_steps; i++) {
+
+ /* Check error reported */
+ if (err_vec[i].error_reported) {
+ offset = ELM_LOCATION_STATUS + ERROR_LOCATION_SIZE * i;
+ reg_val = elm_read_reg(info, offset);
+
+ /* Check correctable error or not */
+ if (reg_val & ECC_CORRECTABLE_MASK) {
+ offset = ELM_ERROR_LOCATION_0 +
+ ERROR_LOCATION_SIZE * i;
+
+ /* Read count of correctable errors */
+ err_vec[i].error_count = reg_val &
+ ECC_NB_ERRORS_MASK;
+
+ /* Update the error locations in error vector */
+ for (j = 0; j < err_vec[i].error_count; j++) {
+
+ reg_val = elm_read_reg(info, offset);
+ err_vec[i].error_loc[j] = reg_val &
+ ECC_ERROR_LOCATION_MASK;
+
+ /* Update error location register */
+ offset += 4;
+ }
+
+ errors += err_vec[i].error_count;
+ } else {
+ err_vec[i].error_uncorrectable = true;
+ }
+
+ /* Clearing interrupts for processed error vectors */
+ elm_write_reg(info, ELM_IRQSTATUS, BIT(i));
+
+ /* Disable page mode */
+ elm_configure_page_mode(info, i, false);
+ }
+ }
+}
+
+static int elm_poll(struct elm_info *info)
+{
+ u32 reg_val;
+
+ reg_val = elm_read_reg(info, ELM_IRQSTATUS);
+
+ /* All error vectors processed */
+ if (reg_val & INTR_STATUS_PAGE_VALID) {
+ elm_write_reg(info, ELM_IRQSTATUS,
+ reg_val & INTR_STATUS_PAGE_VALID);
+ return 0;
+ }
+
+ return -EINPROGRESS;
+}
+
+/**
+ * elm_decode_bch_error_page - Locate error position
+ * @dev: device pointer
+ * @ecc_calc: calculated ECC bytes from GPMC
+ * @err_vec: elm error vectors
+ *
+ * Called with one or more error reported vectors & vectors with
+ * error reported is updated in err_vec[].error_reported
+ */
+int elm_decode_bch_error_page(u8 *ecc_calc, struct elm_errorvec *err_vec)
+{
+ struct elm_info *info = ginfo;
+ u32 reg_val;
+ uint64_t start;
+
+ if (!info)
+ return -ENODEV;
+
+ /* Enable page mode interrupt */
+ reg_val = elm_read_reg(info, ELM_IRQSTATUS);
+ elm_write_reg(info, ELM_IRQSTATUS, reg_val & INTR_STATUS_PAGE_VALID);
+ elm_write_reg(info, ELM_IRQENABLE, INTR_EN_PAGE_MASK);
+
+ /* Load valid ecc byte to syndrome fragment register */
+ elm_load_syndrome(info, err_vec, ecc_calc);
+
+ /* Enable syndrome processing for which syndrome fragment is updated */
+ elm_start_processing(info, err_vec);
+
+ /* Wait for ELM module to finish locating error correction */
+ start = get_time_ns();
+ while (elm_poll(info) < 0) {
+ if (is_timeout(start, SECOND))
+ return -ETIMEDOUT;
+ }
+
+ /* Disable page mode interrupt */
+ reg_val = elm_read_reg(info, ELM_IRQENABLE);
+ elm_write_reg(info, ELM_IRQENABLE, reg_val & ~INTR_EN_PAGE_MASK);
+ elm_error_correction(info, err_vec);
+
+ return 0;
+}
+
+static int elm_probe(struct device_d *dev)
+{
+ struct resource *res;
+ struct elm_info *info;
+
+ info = xzalloc(sizeof(*info));
+
+ info->dev = dev;
+
+ res = dev_request_mem_resource(dev, 0);
+ if (IS_ERR(res))
+ return PTR_ERR(res);
+ info->elm_base = IOMEM(res->start);
+
+ dev->priv = info;
+
+ ginfo = info;
+
+ return 0;
+}
+
+static struct of_device_id elm_compatible[] = {
+ {
+ .compatible = "ti,am3352-elm",
+ }, {
+ /* sentinel */
+ }
+};
+
+static struct driver_d omap_elm_driver = {
+ .name = "omap-elm",
+ .probe = elm_probe,
+ .of_compatible = DRV_OF_COMPAT(elm_compatible)
+};
+coredevice_platform_driver(omap_elm_driver);
diff --git a/include/platform_data/elm.h b/include/platform_data/elm.h
new file mode 100644
index 0000000000..bc5d2edb1d
--- /dev/null
+++ b/include/platform_data/elm.h
@@ -0,0 +1,53 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * BCH Error Location Module
+ *
+ * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
+ */
+
+#ifndef __ELM_H
+#define __ELM_H
+
+enum bch_ecc {
+ BCH4_ECC = 0,
+ BCH8_ECC,
+ BCH16_ECC,
+};
+
+/* ELM support 8 error syndrome process */
+#define ERROR_VECTOR_MAX 8
+
+/**
+ * struct elm_errorvec - error vector for elm
+ * @error_reported: set true for vectors error is reported
+ * @error_uncorrectable: number of uncorrectable errors
+ * @error_count: number of correctable errors in the sector
+ * @error_loc: buffer for error location
+ *
+ */
+struct elm_errorvec {
+ bool error_reported;
+ bool error_uncorrectable;
+ int error_count;
+ int error_loc[16];
+};
+
+#if IS_ENABLED(CONFIG_MTD_NAND_OMAP_ELM)
+int elm_decode_bch_error_page(u8 *ecc_calc, struct elm_errorvec *err_vec);
+int elm_config(enum bch_ecc bch_type, int ecc_steps, int ecc_step_size,
+ int ecc_syndrome_size);
+#else
+static inline int
+elm_decode_bch_error_page(u8 *ecc_calc, struct elm_errorvec *err_vec)
+{
+ return -ENODEV;
+}
+
+static inline int elm_config(enum bch_ecc bch_type, int ecc_steps,
+ int ecc_step_size, int ecc_syndrome_size)
+{
+ return -ENOSYS;
+}
+#endif /* CONFIG_MTD_NAND_OMAP_ELM */
+
+#endif /* __ELM_H */
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-19 16:40:32 +0000