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Diffstat (limited to 'drivers/mtd/nand/qcom_nandc.c')
-rw-r--r--drivers/mtd/nand/qcom_nandc.c2223
1 files changed, 2223 insertions, 0 deletions
diff --git a/drivers/mtd/nand/qcom_nandc.c b/drivers/mtd/nand/qcom_nandc.c
new file mode 100644
index 000000000000..f550a57e6eea
--- /dev/null
+++ b/drivers/mtd/nand/qcom_nandc.c
@@ -0,0 +1,2223 @@
+/*
+ * Copyright (c) 2016, The Linux Foundation. All rights reserved.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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/clk.h>
+#include <linux/slab.h>
+#include <linux/bitops.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/module.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_mtd.h>
+#include <linux/delay.h>
+
+/* NANDc reg offsets */
+#define NAND_FLASH_CMD 0x00
+#define NAND_ADDR0 0x04
+#define NAND_ADDR1 0x08
+#define NAND_FLASH_CHIP_SELECT 0x0c
+#define NAND_EXEC_CMD 0x10
+#define NAND_FLASH_STATUS 0x14
+#define NAND_BUFFER_STATUS 0x18
+#define NAND_DEV0_CFG0 0x20
+#define NAND_DEV0_CFG1 0x24
+#define NAND_DEV0_ECC_CFG 0x28
+#define NAND_DEV1_ECC_CFG 0x2c
+#define NAND_DEV1_CFG0 0x30
+#define NAND_DEV1_CFG1 0x34
+#define NAND_READ_ID 0x40
+#define NAND_READ_STATUS 0x44
+#define NAND_DEV_CMD0 0xa0
+#define NAND_DEV_CMD1 0xa4
+#define NAND_DEV_CMD2 0xa8
+#define NAND_DEV_CMD_VLD 0xac
+#define SFLASHC_BURST_CFG 0xe0
+#define NAND_ERASED_CW_DETECT_CFG 0xe8
+#define NAND_ERASED_CW_DETECT_STATUS 0xec
+#define NAND_EBI2_ECC_BUF_CFG 0xf0
+#define FLASH_BUF_ACC 0x100
+
+#define NAND_CTRL 0xf00
+#define NAND_VERSION 0xf08
+#define NAND_READ_LOCATION_0 0xf20
+#define NAND_READ_LOCATION_1 0xf24
+
+/* dummy register offsets, used by write_reg_dma */
+#define NAND_DEV_CMD1_RESTORE 0xdead
+#define NAND_DEV_CMD_VLD_RESTORE 0xbeef
+
+/* NAND_FLASH_CMD bits */
+#define PAGE_ACC BIT(4)
+#define LAST_PAGE BIT(5)
+
+/* NAND_FLASH_CHIP_SELECT bits */
+#define NAND_DEV_SEL 0
+#define DM_EN BIT(2)
+
+/* NAND_FLASH_STATUS bits */
+#define FS_OP_ERR BIT(4)
+#define FS_READY_BSY_N BIT(5)
+#define FS_MPU_ERR BIT(8)
+#define FS_DEVICE_STS_ERR BIT(16)
+#define FS_DEVICE_WP BIT(23)
+
+/* NAND_BUFFER_STATUS bits */
+#define BS_UNCORRECTABLE_BIT BIT(8)
+#define BS_CORRECTABLE_ERR_MSK 0x1f
+
+/* NAND_DEVn_CFG0 bits */
+#define DISABLE_STATUS_AFTER_WRITE 4
+#define CW_PER_PAGE 6
+#define UD_SIZE_BYTES 9
+#define ECC_PARITY_SIZE_BYTES_RS 19
+#define SPARE_SIZE_BYTES 23
+#define NUM_ADDR_CYCLES 27
+#define STATUS_BFR_READ 30
+#define SET_RD_MODE_AFTER_STATUS 31
+
+/* NAND_DEVn_CFG0 bits */
+#define DEV0_CFG1_ECC_DISABLE 0
+#define WIDE_FLASH 1
+#define NAND_RECOVERY_CYCLES 2
+#define CS_ACTIVE_BSY 5
+#define BAD_BLOCK_BYTE_NUM 6
+#define BAD_BLOCK_IN_SPARE_AREA 16
+#define WR_RD_BSY_GAP 17
+#define ENABLE_BCH_ECC 27
+
+/* NAND_DEV0_ECC_CFG bits */
+#define ECC_CFG_ECC_DISABLE 0
+#define ECC_SW_RESET 1
+#define ECC_MODE 4
+#define ECC_PARITY_SIZE_BYTES_BCH 8
+#define ECC_NUM_DATA_BYTES 16
+#define ECC_FORCE_CLK_OPEN 30
+
+/* NAND_DEV_CMD1 bits */
+#define READ_ADDR 0
+
+/* NAND_DEV_CMD_VLD bits */
+#define READ_START_VLD 0
+
+/* NAND_EBI2_ECC_BUF_CFG bits */
+#define NUM_STEPS 0
+
+/* NAND_ERASED_CW_DETECT_CFG bits */
+#define ERASED_CW_ECC_MASK 1
+#define AUTO_DETECT_RES 0
+#define MASK_ECC (1 << ERASED_CW_ECC_MASK)
+#define RESET_ERASED_DET (1 << AUTO_DETECT_RES)
+#define ACTIVE_ERASED_DET (0 << AUTO_DETECT_RES)
+#define CLR_ERASED_PAGE_DET (RESET_ERASED_DET | MASK_ECC)
+#define SET_ERASED_PAGE_DET (ACTIVE_ERASED_DET | MASK_ECC)
+
+/* NAND_ERASED_CW_DETECT_STATUS bits */
+#define PAGE_ALL_ERASED BIT(7)
+#define CODEWORD_ALL_ERASED BIT(6)
+#define PAGE_ERASED BIT(5)
+#define CODEWORD_ERASED BIT(4)
+#define ERASED_PAGE (PAGE_ALL_ERASED | PAGE_ERASED)
+#define ERASED_CW (CODEWORD_ALL_ERASED | CODEWORD_ERASED)
+
+/* Version Mask */
+#define NAND_VERSION_MAJOR_MASK 0xf0000000
+#define NAND_VERSION_MAJOR_SHIFT 28
+#define NAND_VERSION_MINOR_MASK 0x0fff0000
+#define NAND_VERSION_MINOR_SHIFT 16
+
+/* NAND OP_CMDs */
+#define PAGE_READ 0x2
+#define PAGE_READ_WITH_ECC 0x3
+#define PAGE_READ_WITH_ECC_SPARE 0x4
+#define PROGRAM_PAGE 0x6
+#define PAGE_PROGRAM_WITH_ECC 0x7
+#define PROGRAM_PAGE_SPARE 0x9
+#define BLOCK_ERASE 0xa
+#define FETCH_ID 0xb
+#define RESET_DEVICE 0xd
+
+/*
+ * the NAND controller performs reads/writes with ECC in 516 byte chunks.
+ * the driver calls the chunks 'step' or 'codeword' interchangeably
+ */
+#define NANDC_STEP_SIZE 512
+
+/*
+ * the largest page size we support is 8K, this will have 16 steps/codewords
+ * of 512 bytes each
+ */
+#define MAX_NUM_STEPS (SZ_8K / NANDC_STEP_SIZE)
+
+/* we read at most 3 registers per codeword scan */
+#define MAX_REG_RD (3 * MAX_NUM_STEPS)
+
+/* ECC modes supported by the controller */
+#define ECC_NONE BIT(0)
+#define ECC_RS_4BIT BIT(1)
+#define ECC_BCH_4BIT BIT(2)
+#define ECC_BCH_8BIT BIT(3)
+
+struct desc_info {
+ struct list_head node;
+
+ enum dma_data_direction dir;
+ struct scatterlist sgl;
+ struct dma_async_tx_descriptor *dma_desc;
+};
+
+/*
+ * holds the current register values that we want to write. acts as a contiguous
+ * chunk of memory which we use to write the controller registers through DMA.
+ */
+struct nandc_regs {
+ __le32 cmd;
+ __le32 addr0;
+ __le32 addr1;
+ __le32 chip_sel;
+ __le32 exec;
+
+ __le32 cfg0;
+ __le32 cfg1;
+ __le32 ecc_bch_cfg;
+
+ __le32 clrflashstatus;
+ __le32 clrreadstatus;
+
+ __le32 cmd1;
+ __le32 vld;
+
+ __le32 orig_cmd1;
+ __le32 orig_vld;
+
+ __le32 ecc_buf_cfg;
+};
+
+/*
+ * NAND controller data struct
+ *
+ * @controller: base controller structure
+ * @host_list: list containing all the chips attached to the
+ * controller
+ * @dev: parent device
+ * @base: MMIO base
+ * @base_dma: physical base address of controller registers
+ * @core_clk: controller clock
+ * @aon_clk: another controller clock
+ *
+ * @chan: dma channel
+ * @cmd_crci: ADM DMA CRCI for command flow control
+ * @data_crci: ADM DMA CRCI for data flow control
+ * @desc_list: DMA descriptor list (list of desc_infos)
+ *
+ * @data_buffer: our local DMA buffer for page read/writes,
+ * used when we can't use the buffer provided
+ * by upper layers directly
+ * @buf_size/count/start: markers for chip->read_buf/write_buf functions
+ * @reg_read_buf: local buffer for reading back registers via DMA
+ * @reg_read_pos: marker for data read in reg_read_buf
+ *
+ * @regs: a contiguous chunk of memory for DMA register
+ * writes. contains the register values to be
+ * written to controller
+ * @cmd1/vld: some fixed controller register values
+ * @ecc_modes: supported ECC modes by the current controller,
+ * initialized via DT match data
+ */
+struct qcom_nand_controller {
+ struct nand_hw_control controller;
+ struct list_head host_list;
+
+ struct device *dev;
+
+ void __iomem *base;
+ dma_addr_t base_dma;
+
+ struct clk *core_clk;
+ struct clk *aon_clk;
+
+ struct dma_chan *chan;
+ unsigned int cmd_crci;
+ unsigned int data_crci;
+ struct list_head desc_list;
+
+ u8 *data_buffer;
+ int buf_size;
+ int buf_count;
+ int buf_start;
+
+ __le32 *reg_read_buf;
+ int reg_read_pos;
+
+ struct nandc_regs *regs;
+
+ u32 cmd1, vld;
+ u32 ecc_modes;
+};
+
+/*
+ * NAND chip structure
+ *
+ * @chip: base NAND chip structure
+ * @node: list node to add itself to host_list in
+ * qcom_nand_controller
+ *
+ * @cs: chip select value for this chip
+ * @cw_size: the number of bytes in a single step/codeword
+ * of a page, consisting of all data, ecc, spare
+ * and reserved bytes
+ * @cw_data: the number of bytes within a codeword protected
+ * by ECC
+ * @use_ecc: request the controller to use ECC for the
+ * upcoming read/write
+ * @bch_enabled: flag to tell whether BCH ECC mode is used
+ * @ecc_bytes_hw: ECC bytes used by controller hardware for this
+ * chip
+ * @status: value to be returned if NAND_CMD_STATUS command
+ * is executed
+ * @last_command: keeps track of last command on this chip. used
+ * for reading correct status
+ *
+ * @cfg0, cfg1, cfg0_raw..: NANDc register configurations needed for
+ * ecc/non-ecc mode for the current nand flash
+ * device
+ */
+struct qcom_nand_host {
+ struct nand_chip chip;
+ struct list_head node;
+
+ int cs;
+ int cw_size;
+ int cw_data;
+ bool use_ecc;
+ bool bch_enabled;
+ int ecc_bytes_hw;
+ int spare_bytes;
+ int bbm_size;
+ u8 status;
+ int last_command;
+
+ u32 cfg0, cfg1;
+ u32 cfg0_raw, cfg1_raw;
+ u32 ecc_buf_cfg;
+ u32 ecc_bch_cfg;
+ u32 clrflashstatus;
+ u32 clrreadstatus;
+};
+
+static inline struct qcom_nand_host *to_qcom_nand_host(struct nand_chip *chip)
+{
+ return container_of(chip, struct qcom_nand_host, chip);
+}
+
+static inline struct qcom_nand_controller *
+get_qcom_nand_controller(struct nand_chip *chip)
+{
+ return container_of(chip->controller, struct qcom_nand_controller,
+ controller);
+}
+
+static inline u32 nandc_read(struct qcom_nand_controller *nandc, int offset)
+{
+ return ioread32(nandc->base + offset);
+}
+
+static inline void nandc_write(struct qcom_nand_controller *nandc, int offset,
+ u32 val)
+{
+ iowrite32(val, nandc->base + offset);
+}
+
+static __le32 *offset_to_nandc_reg(struct nandc_regs *regs, int offset)
+{
+ switch (offset) {
+ case NAND_FLASH_CMD:
+ return &regs->cmd;
+ case NAND_ADDR0:
+ return &regs->addr0;
+ case NAND_ADDR1:
+ return &regs->addr1;
+ case NAND_FLASH_CHIP_SELECT:
+ return &regs->chip_sel;
+ case NAND_EXEC_CMD:
+ return &regs->exec;
+ case NAND_FLASH_STATUS:
+ return &regs->clrflashstatus;
+ case NAND_DEV0_CFG0:
+ return &regs->cfg0;
+ case NAND_DEV0_CFG1:
+ return &regs->cfg1;
+ case NAND_DEV0_ECC_CFG:
+ return &regs->ecc_bch_cfg;
+ case NAND_READ_STATUS:
+ return &regs->clrreadstatus;
+ case NAND_DEV_CMD1:
+ return &regs->cmd1;
+ case NAND_DEV_CMD1_RESTORE:
+ return &regs->orig_cmd1;
+ case NAND_DEV_CMD_VLD:
+ return &regs->vld;
+ case NAND_DEV_CMD_VLD_RESTORE:
+ return &regs->orig_vld;
+ case NAND_EBI2_ECC_BUF_CFG:
+ return &regs->ecc_buf_cfg;
+ default:
+ return NULL;
+ }
+}
+
+static void nandc_set_reg(struct qcom_nand_controller *nandc, int offset,
+ u32 val)
+{
+ struct nandc_regs *regs = nandc->regs;
+ __le32 *reg;
+
+ reg = offset_to_nandc_reg(regs, offset);
+
+ if (reg)
+ *reg = cpu_to_le32(val);
+}
+
+/* helper to configure address register values */
+static void set_address(struct qcom_nand_host *host, u16 column, int page)
+{
+ struct nand_chip *chip = &host->chip;
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+
+ if (chip->options & NAND_BUSWIDTH_16)
+ column >>= 1;
+
+ nandc_set_reg(nandc, NAND_ADDR0, page << 16 | column);
+ nandc_set_reg(nandc, NAND_ADDR1, page >> 16 & 0xff);
+}
+
+/*
+ * update_rw_regs: set up read/write register values, these will be
+ * written to the NAND controller registers via DMA
+ *
+ * @num_cw: number of steps for the read/write operation
+ * @read: read or write operation
+ */
+static void update_rw_regs(struct qcom_nand_host *host, int num_cw, bool read)
+{
+ struct nand_chip *chip = &host->chip;
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ u32 cmd, cfg0, cfg1, ecc_bch_cfg;
+
+ if (read) {
+ if (host->use_ecc)
+ cmd = PAGE_READ_WITH_ECC | PAGE_ACC | LAST_PAGE;
+ else
+ cmd = PAGE_READ | PAGE_ACC | LAST_PAGE;
+ } else {
+ cmd = PROGRAM_PAGE | PAGE_ACC | LAST_PAGE;
+ }
+
+ if (host->use_ecc) {
+ cfg0 = (host->cfg0 & ~(7U << CW_PER_PAGE)) |
+ (num_cw - 1) << CW_PER_PAGE;
+
+ cfg1 = host->cfg1;
+ ecc_bch_cfg = host->ecc_bch_cfg;
+ } else {
+ cfg0 = (host->cfg0_raw & ~(7U << CW_PER_PAGE)) |
+ (num_cw - 1) << CW_PER_PAGE;
+
+ cfg1 = host->cfg1_raw;
+ ecc_bch_cfg = 1 << ECC_CFG_ECC_DISABLE;
+ }
+
+ nandc_set_reg(nandc, NAND_FLASH_CMD, cmd);
+ nandc_set_reg(nandc, NAND_DEV0_CFG0, cfg0);
+ nandc_set_reg(nandc, NAND_DEV0_CFG1, cfg1);
+ nandc_set_reg(nandc, NAND_DEV0_ECC_CFG, ecc_bch_cfg);
+ nandc_set_reg(nandc, NAND_EBI2_ECC_BUF_CFG, host->ecc_buf_cfg);
+ nandc_set_reg(nandc, NAND_FLASH_STATUS, host->clrflashstatus);
+ nandc_set_reg(nandc, NAND_READ_STATUS, host->clrreadstatus);
+ nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
+}
+
+static int prep_dma_desc(struct qcom_nand_controller *nandc, bool read,
+ int reg_off, const void *vaddr, int size,
+ bool flow_control)
+{
+ struct desc_info *desc;
+ struct dma_async_tx_descriptor *dma_desc;
+ struct scatterlist *sgl;
+ struct dma_slave_config slave_conf;
+ enum dma_transfer_direction dir_eng;
+ int ret;
+
+ desc = kzalloc(sizeof(*desc), GFP_KERNEL);
+ if (!desc)
+ return -ENOMEM;
+
+ sgl = &desc->sgl;
+
+ sg_init_one(sgl, vaddr, size);
+
+ if (read) {
+ dir_eng = DMA_DEV_TO_MEM;
+ desc->dir = DMA_FROM_DEVICE;
+ } else {
+ dir_eng = DMA_MEM_TO_DEV;
+ desc->dir = DMA_TO_DEVICE;
+ }
+
+ ret = dma_map_sg(nandc->dev, sgl, 1, desc->dir);
+ if (ret == 0) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ memset(&slave_conf, 0x00, sizeof(slave_conf));
+
+ slave_conf.device_fc = flow_control;
+ if (read) {
+ slave_conf.src_maxburst = 16;
+ slave_conf.src_addr = nandc->base_dma + reg_off;
+ slave_conf.slave_id = nandc->data_crci;
+ } else {
+ slave_conf.dst_maxburst = 16;
+ slave_conf.dst_addr = nandc->base_dma + reg_off;
+ slave_conf.slave_id = nandc->cmd_crci;
+ }
+
+ ret = dmaengine_slave_config(nandc->chan, &slave_conf);
+ if (ret) {
+ dev_err(nandc->dev, "failed to configure dma channel\n");
+ goto err;
+ }
+
+ dma_desc = dmaengine_prep_slave_sg(nandc->chan, sgl, 1, dir_eng, 0);
+ if (!dma_desc) {
+ dev_err(nandc->dev, "failed to prepare desc\n");
+ ret = -EINVAL;
+ goto err;
+ }
+
+ desc->dma_desc = dma_desc;
+
+ list_add_tail(&desc->node, &nandc->desc_list);
+
+ return 0;
+err:
+ kfree(desc);
+
+ return ret;
+}
+
+/*
+ * read_reg_dma: prepares a descriptor to read a given number of
+ * contiguous registers to the reg_read_buf pointer
+ *
+ * @first: offset of the first register in the contiguous block
+ * @num_regs: number of registers to read
+ */
+static int read_reg_dma(struct qcom_nand_controller *nandc, int first,
+ int num_regs)
+{
+ bool flow_control = false;
+ void *vaddr;
+ int size;
+
+ if (first == NAND_READ_ID || first == NAND_FLASH_STATUS)
+ flow_control = true;
+
+ size = num_regs * sizeof(u32);
+ vaddr = nandc->reg_read_buf + nandc->reg_read_pos;
+ nandc->reg_read_pos += num_regs;
+
+ return prep_dma_desc(nandc, true, first, vaddr, size, flow_control);
+}
+
+/*
+ * write_reg_dma: prepares a descriptor to write a given number of
+ * contiguous registers
+ *
+ * @first: offset of the first register in the contiguous block
+ * @num_regs: number of registers to write
+ */
+static int write_reg_dma(struct qcom_nand_controller *nandc, int first,
+ int num_regs)
+{
+ bool flow_control = false;
+ struct nandc_regs *regs = nandc->regs;
+ void *vaddr;
+ int size;
+
+ vaddr = offset_to_nandc_reg(regs, first);
+
+ if (first == NAND_FLASH_CMD)
+ flow_control = true;
+
+ if (first == NAND_DEV_CMD1_RESTORE)
+ first = NAND_DEV_CMD1;
+
+ if (first == NAND_DEV_CMD_VLD_RESTORE)
+ first = NAND_DEV_CMD_VLD;
+
+ size = num_regs * sizeof(u32);
+
+ return prep_dma_desc(nandc, false, first, vaddr, size, flow_control);
+}
+
+/*
+ * read_data_dma: prepares a DMA descriptor to transfer data from the
+ * controller's internal buffer to the buffer 'vaddr'
+ *
+ * @reg_off: offset within the controller's data buffer
+ * @vaddr: virtual address of the buffer we want to write to
+ * @size: DMA transaction size in bytes
+ */
+static int read_data_dma(struct qcom_nand_controller *nandc, int reg_off,
+ const u8 *vaddr, int size)
+{
+ return prep_dma_desc(nandc, true, reg_off, vaddr, size, false);
+}
+
+/*
+ * write_data_dma: prepares a DMA descriptor to transfer data from
+ * 'vaddr' to the controller's internal buffer
+ *
+ * @reg_off: offset within the controller's data buffer
+ * @vaddr: virtual address of the buffer we want to read from
+ * @size: DMA transaction size in bytes
+ */
+static int write_data_dma(struct qcom_nand_controller *nandc, int reg_off,
+ const u8 *vaddr, int size)
+{
+ return prep_dma_desc(nandc, false, reg_off, vaddr, size, false);
+}
+
+/*
+ * helper to prepare dma descriptors to configure registers needed for reading a
+ * codeword/step in a page
+ */
+static void config_cw_read(struct qcom_nand_controller *nandc)
+{
+ write_reg_dma(nandc, NAND_FLASH_CMD, 3);
+ write_reg_dma(nandc, NAND_DEV0_CFG0, 3);
+ write_reg_dma(nandc, NAND_EBI2_ECC_BUF_CFG, 1);
+
+ write_reg_dma(nandc, NAND_EXEC_CMD, 1);
+
+ read_reg_dma(nandc, NAND_FLASH_STATUS, 2);
+ read_reg_dma(nandc, NAND_ERASED_CW_DETECT_STATUS, 1);
+}
+
+/*
+ * helpers to prepare dma descriptors used to configure registers needed for
+ * writing a codeword/step in a page
+ */
+static void config_cw_write_pre(struct qcom_nand_controller *nandc)
+{
+ write_reg_dma(nandc, NAND_FLASH_CMD, 3);
+ write_reg_dma(nandc, NAND_DEV0_CFG0, 3);
+ write_reg_dma(nandc, NAND_EBI2_ECC_BUF_CFG, 1);
+}
+
+static void config_cw_write_post(struct qcom_nand_controller *nandc)
+{
+ write_reg_dma(nandc, NAND_EXEC_CMD, 1);
+
+ read_reg_dma(nandc, NAND_FLASH_STATUS, 1);
+
+ write_reg_dma(nandc, NAND_FLASH_STATUS, 1);
+ write_reg_dma(nandc, NAND_READ_STATUS, 1);
+}
+
+/*
+ * the following functions are used within chip->cmdfunc() to perform different
+ * NAND_CMD_* commands
+ */
+
+/* sets up descriptors for NAND_CMD_PARAM */
+static int nandc_param(struct qcom_nand_host *host)
+{
+ struct nand_chip *chip = &host->chip;
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+
+ /*
+ * NAND_CMD_PARAM is called before we know much about the FLASH chip
+ * in use. we configure the controller to perform a raw read of 512
+ * bytes to read onfi params
+ */
+ nandc_set_reg(nandc, NAND_FLASH_CMD, PAGE_READ | PAGE_ACC | LAST_PAGE);
+ nandc_set_reg(nandc, NAND_ADDR0, 0);
+ nandc_set_reg(nandc, NAND_ADDR1, 0);
+ nandc_set_reg(nandc, NAND_DEV0_CFG0, 0 << CW_PER_PAGE
+ | 512 << UD_SIZE_BYTES
+ | 5 << NUM_ADDR_CYCLES
+ | 0 << SPARE_SIZE_BYTES);
+ nandc_set_reg(nandc, NAND_DEV0_CFG1, 7 << NAND_RECOVERY_CYCLES
+ | 0 << CS_ACTIVE_BSY
+ | 17 << BAD_BLOCK_BYTE_NUM
+ | 1 << BAD_BLOCK_IN_SPARE_AREA
+ | 2 << WR_RD_BSY_GAP
+ | 0 << WIDE_FLASH
+ | 1 << DEV0_CFG1_ECC_DISABLE);
+ nandc_set_reg(nandc, NAND_EBI2_ECC_BUF_CFG, 1 << ECC_CFG_ECC_DISABLE);
+
+ /* configure CMD1 and VLD for ONFI param probing */
+ nandc_set_reg(nandc, NAND_DEV_CMD_VLD,
+ (nandc->vld & ~(1 << READ_START_VLD))
+ | 0 << READ_START_VLD);
+ nandc_set_reg(nandc, NAND_DEV_CMD1,
+ (nandc->cmd1 & ~(0xFF << READ_ADDR))
+ | NAND_CMD_PARAM << READ_ADDR);
+
+ nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
+
+ nandc_set_reg(nandc, NAND_DEV_CMD1_RESTORE, nandc->cmd1);
+ nandc_set_reg(nandc, NAND_DEV_CMD_VLD_RESTORE, nandc->vld);
+
+ write_reg_dma(nandc, NAND_DEV_CMD_VLD, 1);
+ write_reg_dma(nandc, NAND_DEV_CMD1, 1);
+
+ nandc->buf_count = 512;
+ memset(nandc->data_buffer, 0xff, nandc->buf_count);
+
+ config_cw_read(nandc);
+
+ read_data_dma(nandc, FLASH_BUF_ACC, nandc->data_buffer,
+ nandc->buf_count);
+
+ /* restore CMD1 and VLD regs */
+ write_reg_dma(nandc, NAND_DEV_CMD1_RESTORE, 1);
+ write_reg_dma(nandc, NAND_DEV_CMD_VLD_RESTORE, 1);
+
+ return 0;
+}
+
+/* sets up descriptors for NAND_CMD_ERASE1 */
+static int erase_block(struct qcom_nand_host *host, int page_addr)
+{
+ struct nand_chip *chip = &host->chip;
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+
+ nandc_set_reg(nandc, NAND_FLASH_CMD,
+ BLOCK_ERASE | PAGE_ACC | LAST_PAGE);
+ nandc_set_reg(nandc, NAND_ADDR0, page_addr);
+ nandc_set_reg(nandc, NAND_ADDR1, 0);
+ nandc_set_reg(nandc, NAND_DEV0_CFG0,
+ host->cfg0_raw & ~(7 << CW_PER_PAGE));
+ nandc_set_reg(nandc, NAND_DEV0_CFG1, host->cfg1_raw);
+ nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
+ nandc_set_reg(nandc, NAND_FLASH_STATUS, host->clrflashstatus);
+ nandc_set_reg(nandc, NAND_READ_STATUS, host->clrreadstatus);
+
+ write_reg_dma(nandc, NAND_FLASH_CMD, 3);
+ write_reg_dma(nandc, NAND_DEV0_CFG0, 2);
+ write_reg_dma(nandc, NAND_EXEC_CMD, 1);
+
+ read_reg_dma(nandc, NAND_FLASH_STATUS, 1);
+
+ write_reg_dma(nandc, NAND_FLASH_STATUS, 1);
+ write_reg_dma(nandc, NAND_READ_STATUS, 1);
+
+ return 0;
+}
+
+/* sets up descriptors for NAND_CMD_READID */
+static int read_id(struct qcom_nand_host *host, int column)
+{
+ struct nand_chip *chip = &host->chip;
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+
+ if (column == -1)
+ return 0;
+
+ nandc_set_reg(nandc, NAND_FLASH_CMD, FETCH_ID);
+ nandc_set_reg(nandc, NAND_ADDR0, column);
+ nandc_set_reg(nandc, NAND_ADDR1, 0);
+ nandc_set_reg(nandc, NAND_FLASH_CHIP_SELECT, DM_EN);
+ nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
+
+ write_reg_dma(nandc, NAND_FLASH_CMD, 4);
+ write_reg_dma(nandc, NAND_EXEC_CMD, 1);
+
+ read_reg_dma(nandc, NAND_READ_ID, 1);
+
+ return 0;
+}
+
+/* sets up descriptors for NAND_CMD_RESET */
+static int reset(struct qcom_nand_host *host)
+{
+ struct nand_chip *chip = &host->chip;
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+
+ nandc_set_reg(nandc, NAND_FLASH_CMD, RESET_DEVICE);
+ nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
+
+ write_reg_dma(nandc, NAND_FLASH_CMD, 1);
+ write_reg_dma(nandc, NAND_EXEC_CMD, 1);
+
+ read_reg_dma(nandc, NAND_FLASH_STATUS, 1);
+
+ return 0;
+}
+
+/* helpers to submit/free our list of dma descriptors */
+static int submit_descs(struct qcom_nand_controller *nandc)
+{
+ struct desc_info *desc;
+ dma_cookie_t cookie = 0;
+
+ list_for_each_entry(desc, &nandc->desc_list, node)
+ cookie = dmaengine_submit(desc->dma_desc);
+
+ if (dma_sync_wait(nandc->chan, cookie) != DMA_COMPLETE)
+ return -ETIMEDOUT;
+
+ return 0;
+}
+
+static void free_descs(struct qcom_nand_controller *nandc)
+{
+ struct desc_info *desc, *n;
+
+ list_for_each_entry_safe(desc, n, &nandc->desc_list, node) {
+ list_del(&desc->node);
+ dma_unmap_sg(nandc->dev, &desc->sgl, 1, desc->dir);
+ kfree(desc);
+ }
+}
+
+/* reset the register read buffer for next NAND operation */
+static void clear_read_regs(struct qcom_nand_controller *nandc)
+{
+ nandc->reg_read_pos = 0;
+ memset(nandc->reg_read_buf, 0,
+ MAX_REG_RD * sizeof(*nandc->reg_read_buf));
+}
+
+static void pre_command(struct qcom_nand_host *host, int command)
+{
+ struct nand_chip *chip = &host->chip;
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+
+ nandc->buf_count = 0;
+ nandc->buf_start = 0;
+ host->use_ecc = false;
+ host->last_command = command;
+
+ clear_read_regs(nandc);
+}
+
+/*
+ * this is called after NAND_CMD_PAGEPROG and NAND_CMD_ERASE1 to set our
+ * privately maintained status byte, this status byte can be read after
+ * NAND_CMD_STATUS is called
+ */
+static void parse_erase_write_errors(struct qcom_nand_host *host, int command)
+{
+ struct nand_chip *chip = &host->chip;
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ int num_cw;
+ int i;
+
+ num_cw = command == NAND_CMD_PAGEPROG ? ecc->steps : 1;
+
+ for (i = 0; i < num_cw; i++) {
+ u32 flash_status = le32_to_cpu(nandc->reg_read_buf[i]);
+
+ if (flash_status & FS_MPU_ERR)
+ host->status &= ~NAND_STATUS_WP;
+
+ if (flash_status & FS_OP_ERR || (i == (num_cw - 1) &&
+ (flash_status &
+ FS_DEVICE_STS_ERR)))
+ host->status |= NAND_STATUS_FAIL;
+ }
+}
+
+static void post_command(struct qcom_nand_host *host, int command)
+{
+ struct nand_chip *chip = &host->chip;
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+
+ switch (command) {
+ case NAND_CMD_READID:
+ memcpy(nandc->data_buffer, nandc->reg_read_buf,
+ nandc->buf_count);
+ break;
+ case NAND_CMD_PAGEPROG:
+ case NAND_CMD_ERASE1:
+ parse_erase_write_errors(host, command);
+ break;
+ default:
+ break;
+ }
+}
+
+/*
+ * Implements chip->cmdfunc. It's only used for a limited set of commands.
+ * The rest of the commands wouldn't be called by upper layers. For example,
+ * NAND_CMD_READOOB would never be called because we have our own versions
+ * of read_oob ops for nand_ecc_ctrl.
+ */
+static void qcom_nandc_command(struct mtd_info *mtd, unsigned int command,
+ int column, int page_addr)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct qcom_nand_host *host = to_qcom_nand_host(chip);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ bool wait = false;
+ int ret = 0;
+
+ pre_command(host, command);
+
+ switch (command) {
+ case NAND_CMD_RESET:
+ ret = reset(host);
+ wait = true;
+ break;
+
+ case NAND_CMD_READID:
+ nandc->buf_count = 4;
+ ret = read_id(host, column);
+ wait = true;
+ break;
+
+ case NAND_CMD_PARAM:
+ ret = nandc_param(host);
+ wait = true;
+ break;
+
+ case NAND_CMD_ERASE1:
+ ret = erase_block(host, page_addr);
+ wait = true;
+ break;
+
+ case NAND_CMD_READ0:
+ /* we read the entire page for now */
+ WARN_ON(column != 0);
+
+ host->use_ecc = true;
+ set_address(host, 0, page_addr);
+ update_rw_regs(host, ecc->steps, true);
+ break;
+
+ case NAND_CMD_SEQIN:
+ WARN_ON(column != 0);
+ set_address(host, 0, page_addr);
+ break;
+
+ case NAND_CMD_PAGEPROG:
+ case NAND_CMD_STATUS:
+ case NAND_CMD_NONE:
+ default:
+ break;
+ }
+
+ if (ret) {
+ dev_err(nandc->dev, "failure executing command %d\n",
+ command);
+ free_descs(nandc);
+ return;
+ }
+
+ if (wait) {
+ ret = submit_descs(nandc);
+ if (ret)
+ dev_err(nandc->dev,
+ "failure submitting descs for command %d\n",
+ command);
+ }
+
+ free_descs(nandc);
+
+ post_command(host, command);
+}
+
+/*
+ * when using BCH ECC, the HW flags an error in NAND_FLASH_STATUS if it read
+ * an erased CW, and reports an erased CW in NAND_ERASED_CW_DETECT_STATUS.
+ *
+ * when using RS ECC, the HW reports the same erros when reading an erased CW,
+ * but it notifies that it is an erased CW by placing special characters at
+ * certain offsets in the buffer.
+ *
+ * verify if the page is erased or not, and fix up the page for RS ECC by
+ * replacing the special characters with 0xff.
+ */
+static bool erased_chunk_check_and_fixup(u8 *data_buf, int data_len)
+{
+ u8 empty1, empty2;
+
+ /*
+ * an erased page flags an error in NAND_FLASH_STATUS, check if the page
+ * is erased by looking for 0x54s at offsets 3 and 175 from the
+ * beginning of each codeword
+ */
+
+ empty1 = data_buf[3];
+ empty2 = data_buf[175];
+
+ /*
+ * if the erased codework markers, if they exist override them with
+ * 0xffs
+ */
+ if ((empty1 == 0x54 && empty2 == 0xff) ||
+ (empty1 == 0xff && empty2 == 0x54)) {
+ data_buf[3] = 0xff;
+ data_buf[175] = 0xff;
+ }
+
+ /*
+ * check if the entire chunk contains 0xffs or not. if it doesn't, then
+ * restore the original values at the special offsets
+ */
+ if (memchr_inv(data_buf, 0xff, data_len)) {
+ data_buf[3] = empty1;
+ data_buf[175] = empty2;
+
+ return false;
+ }
+
+ return true;
+}
+
+struct read_stats {
+ __le32 flash;
+ __le32 buffer;
+ __le32 erased_cw;
+};
+
+/*
+ * reads back status registers set by the controller to notify page read
+ * errors. this is equivalent to what 'ecc->correct()' would do.
+ */
+static int parse_read_errors(struct qcom_nand_host *host, u8 *data_buf,
+ u8 *oob_buf)
+{
+ struct nand_chip *chip = &host->chip;
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ struct mtd_info *mtd = nand_to_mtd(chip);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ unsigned int max_bitflips = 0;
+ struct read_stats *buf;
+ int i;
+
+ buf = (struct read_stats *)nandc->reg_read_buf;
+
+ for (i = 0; i < ecc->steps; i++, buf++) {
+ u32 flash, buffer, erased_cw;
+ int data_len, oob_len;
+
+ if (i == (ecc->steps - 1)) {
+ data_len = ecc->size - ((ecc->steps - 1) << 2);
+ oob_len = ecc->steps << 2;
+ } else {
+ data_len = host->cw_data;
+ oob_len = 0;
+ }
+
+ flash = le32_to_cpu(buf->flash);
+ buffer = le32_to_cpu(buf->buffer);
+ erased_cw = le32_to_cpu(buf->erased_cw);
+
+ if (flash & (FS_OP_ERR | FS_MPU_ERR)) {
+ bool erased;
+
+ /* ignore erased codeword errors */
+ if (host->bch_enabled) {
+ erased = (erased_cw & ERASED_CW) == ERASED_CW ?
+ true : false;
+ } else {
+ erased = erased_chunk_check_and_fixup(data_buf,
+ data_len);
+ }
+
+ if (erased) {
+ data_buf += data_len;
+ if (oob_buf)
+ oob_buf += oob_len + ecc->bytes;
+ continue;
+ }
+
+ if (buffer & BS_UNCORRECTABLE_BIT) {
+ int ret, ecclen, extraooblen;
+ void *eccbuf;
+
+ eccbuf = oob_buf ? oob_buf + oob_len : NULL;
+ ecclen = oob_buf ? host->ecc_bytes_hw : 0;
+ extraooblen = oob_buf ? oob_len : 0;
+
+ /*
+ * make sure it isn't an erased page reported
+ * as not-erased by HW because of a few bitflips
+ */
+ ret = nand_check_erased_ecc_chunk(data_buf,
+ data_len, eccbuf, ecclen, oob_buf,
+ extraooblen, ecc->strength);
+ if (ret < 0) {
+ mtd->ecc_stats.failed++;
+ } else {
+ mtd->ecc_stats.corrected += ret;
+ max_bitflips =
+ max_t(unsigned int, max_bitflips, ret);
+ }
+ }
+ } else {
+ unsigned int stat;
+
+ stat = buffer & BS_CORRECTABLE_ERR_MSK;
+ mtd->ecc_stats.corrected += stat;
+ max_bitflips = max(max_bitflips, stat);
+ }
+
+ data_buf += data_len;
+ if (oob_buf)
+ oob_buf += oob_len + ecc->bytes;
+ }
+
+ return max_bitflips;
+}
+
+/*
+ * helper to perform the actual page read operation, used by ecc->read_page(),
+ * ecc->read_oob()
+ */
+static int read_page_ecc(struct qcom_nand_host *host, u8 *data_buf,
+ u8 *oob_buf)
+{
+ struct nand_chip *chip = &host->chip;
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ int i, ret;
+
+ /* queue cmd descs for each codeword */
+ for (i = 0; i < ecc->steps; i++) {
+ int data_size, oob_size;
+
+ if (i == (ecc->steps - 1)) {
+ data_size = ecc->size - ((ecc->steps - 1) << 2);
+ oob_size = (ecc->steps << 2) + host->ecc_bytes_hw +
+ host->spare_bytes;
+ } else {
+ data_size = host->cw_data;
+ oob_size = host->ecc_bytes_hw + host->spare_bytes;
+ }
+
+ config_cw_read(nandc);
+
+ if (data_buf)
+ read_data_dma(nandc, FLASH_BUF_ACC, data_buf,
+ data_size);
+
+ /*
+ * when ecc is enabled, the controller doesn't read the real
+ * or dummy bad block markers in each chunk. To maintain a
+ * consistent layout across RAW and ECC reads, we just
+ * leave the real/dummy BBM offsets empty (i.e, filled with
+ * 0xffs)
+ */
+ if (oob_buf) {
+ int j;
+
+ for (j = 0; j < host->bbm_size; j++)
+ *oob_buf++ = 0xff;
+
+ read_data_dma(nandc, FLASH_BUF_ACC + data_size,
+ oob_buf, oob_size);
+ }
+
+ if (data_buf)
+ data_buf += data_size;
+ if (oob_buf)
+ oob_buf += oob_size;
+ }
+
+ ret = submit_descs(nandc);
+ if (ret)
+ dev_err(nandc->dev, "failure to read page/oob\n");
+
+ free_descs(nandc);
+
+ return ret;
+}
+
+/*
+ * a helper that copies the last step/codeword of a page (containing free oob)
+ * into our local buffer
+ */
+static int copy_last_cw(struct qcom_nand_host *host, int page)
+{
+ struct nand_chip *chip = &host->chip;
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ int size;
+ int ret;
+
+ clear_read_regs(nandc);
+
+ size = host->use_ecc ? host->cw_data : host->cw_size;
+
+ /* prepare a clean read buffer */
+ memset(nandc->data_buffer, 0xff, size);
+
+ set_address(host, host->cw_size * (ecc->steps - 1), page);
+ update_rw_regs(host, 1, true);
+
+ config_cw_read(nandc);
+
+ read_data_dma(nandc, FLASH_BUF_ACC, nandc->data_buffer, size);
+
+ ret = submit_descs(nandc);
+ if (ret)
+ dev_err(nandc->dev, "failed to copy last codeword\n");
+
+ free_descs(nandc);
+
+ return ret;
+}
+
+/* implements ecc->read_page() */
+static int qcom_nandc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
+ uint8_t *buf, int oob_required, int page)
+{
+ struct qcom_nand_host *host = to_qcom_nand_host(chip);
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ u8 *data_buf, *oob_buf = NULL;
+ int ret;
+
+ data_buf = buf;
+ oob_buf = oob_required ? chip->oob_poi : NULL;
+
+ ret = read_page_ecc(host, data_buf, oob_buf);
+ if (ret) {
+ dev_err(nandc->dev, "failure to read page\n");
+ return ret;
+ }
+
+ return parse_read_errors(host, data_buf, oob_buf);
+}
+
+/* implements ecc->read_page_raw() */
+static int qcom_nandc_read_page_raw(struct mtd_info *mtd,
+ struct nand_chip *chip, uint8_t *buf,
+ int oob_required, int page)
+{
+ struct qcom_nand_host *host = to_qcom_nand_host(chip);
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ u8 *data_buf, *oob_buf;
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ int i, ret;
+
+ data_buf = buf;
+ oob_buf = chip->oob_poi;
+
+ host->use_ecc = false;
+ update_rw_regs(host, ecc->steps, true);
+
+ for (i = 0; i < ecc->steps; i++) {
+ int data_size1, data_size2, oob_size1, oob_size2;
+ int reg_off = FLASH_BUF_ACC;
+
+ data_size1 = mtd->writesize - host->cw_size * (ecc->steps - 1);
+ oob_size1 = host->bbm_size;
+
+ if (i == (ecc->steps - 1)) {
+ data_size2 = ecc->size - data_size1 -
+ ((ecc->steps - 1) << 2);
+ oob_size2 = (ecc->steps << 2) + host->ecc_bytes_hw +
+ host->spare_bytes;
+ } else {
+ data_size2 = host->cw_data - data_size1;
+ oob_size2 = host->ecc_bytes_hw + host->spare_bytes;
+ }
+
+ config_cw_read(nandc);
+
+ read_data_dma(nandc, reg_off, data_buf, data_size1);
+ reg_off += data_size1;
+ data_buf += data_size1;
+
+ read_data_dma(nandc, reg_off, oob_buf, oob_size1);
+ reg_off += oob_size1;
+ oob_buf += oob_size1;
+
+ read_data_dma(nandc, reg_off, data_buf, data_size2);
+ reg_off += data_size2;
+ data_buf += data_size2;
+
+ read_data_dma(nandc, reg_off, oob_buf, oob_size2);
+ oob_buf += oob_size2;
+ }
+
+ ret = submit_descs(nandc);
+ if (ret)
+ dev_err(nandc->dev, "failure to read raw page\n");
+
+ free_descs(nandc);
+
+ return 0;
+}
+
+/* implements ecc->read_oob() */
+static int qcom_nandc_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
+ int page)
+{
+ struct qcom_nand_host *host = to_qcom_nand_host(chip);
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ int ret;
+
+ clear_read_regs(nandc);
+
+ host->use_ecc = true;
+ set_address(host, 0, page);
+ update_rw_regs(host, ecc->steps, true);
+
+ ret = read_page_ecc(host, NULL, chip->oob_poi);
+ if (ret)
+ dev_err(nandc->dev, "failure to read oob\n");
+
+ return ret;
+}
+
+/* implements ecc->write_page() */
+static int qcom_nandc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
+ const uint8_t *buf, int oob_required, int page)
+{
+ struct qcom_nand_host *host = to_qcom_nand_host(chip);
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ u8 *data_buf, *oob_buf;
+ int i, ret;
+
+ clear_read_regs(nandc);
+
+ data_buf = (u8 *)buf;
+ oob_buf = chip->oob_poi;
+
+ host->use_ecc = true;
+ update_rw_regs(host, ecc->steps, false);
+
+ for (i = 0; i < ecc->steps; i++) {
+ int data_size, oob_size;
+
+ if (i == (ecc->steps - 1)) {
+ data_size = ecc->size - ((ecc->steps - 1) << 2);
+ oob_size = (ecc->steps << 2) + host->ecc_bytes_hw +
+ host->spare_bytes;
+ } else {
+ data_size = host->cw_data;
+ oob_size = ecc->bytes;
+ }
+
+ config_cw_write_pre(nandc);
+
+ write_data_dma(nandc, FLASH_BUF_ACC, data_buf, data_size);
+
+ /*
+ * when ECC is enabled, we don't really need to write anything
+ * to oob for the first n - 1 codewords since these oob regions
+ * just contain ECC bytes that's written by the controller
+ * itself. For the last codeword, we skip the bbm positions and
+ * write to the free oob area.
+ */
+ if (i == (ecc->steps - 1)) {
+ oob_buf += host->bbm_size;
+
+ write_data_dma(nandc, FLASH_BUF_ACC + data_size,
+ oob_buf, oob_size);
+ }
+
+ config_cw_write_post(nandc);
+
+ data_buf += data_size;
+ oob_buf += oob_size;
+ }
+
+ ret = submit_descs(nandc);
+ if (ret)
+ dev_err(nandc->dev, "failure to write page\n");
+
+ free_descs(nandc);
+
+ return ret;
+}
+
+/* implements ecc->write_page_raw() */
+static int qcom_nandc_write_page_raw(struct mtd_info *mtd,
+ struct nand_chip *chip, const uint8_t *buf,
+ int oob_required, int page)
+{
+ struct qcom_nand_host *host = to_qcom_nand_host(chip);
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ u8 *data_buf, *oob_buf;
+ int i, ret;
+
+ clear_read_regs(nandc);
+
+ data_buf = (u8 *)buf;
+ oob_buf = chip->oob_poi;
+
+ host->use_ecc = false;
+ update_rw_regs(host, ecc->steps, false);
+
+ for (i = 0; i < ecc->steps; i++) {
+ int data_size1, data_size2, oob_size1, oob_size2;
+ int reg_off = FLASH_BUF_ACC;
+
+ data_size1 = mtd->writesize - host->cw_size * (ecc->steps - 1);
+ oob_size1 = host->bbm_size;
+
+ if (i == (ecc->steps - 1)) {
+ data_size2 = ecc->size - data_size1 -
+ ((ecc->steps - 1) << 2);
+ oob_size2 = (ecc->steps << 2) + host->ecc_bytes_hw +
+ host->spare_bytes;
+ } else {
+ data_size2 = host->cw_data - data_size1;
+ oob_size2 = host->ecc_bytes_hw + host->spare_bytes;
+ }
+
+ config_cw_write_pre(nandc);
+
+ write_data_dma(nandc, reg_off, data_buf, data_size1);
+ reg_off += data_size1;
+ data_buf += data_size1;
+
+ write_data_dma(nandc, reg_off, oob_buf, oob_size1);
+ reg_off += oob_size1;
+ oob_buf += oob_size1;
+
+ write_data_dma(nandc, reg_off, data_buf, data_size2);
+ reg_off += data_size2;
+ data_buf += data_size2;
+
+ write_data_dma(nandc, reg_off, oob_buf, oob_size2);
+ oob_buf += oob_size2;
+
+ config_cw_write_post(nandc);
+ }
+
+ ret = submit_descs(nandc);
+ if (ret)
+ dev_err(nandc->dev, "failure to write raw page\n");
+
+ free_descs(nandc);
+
+ return ret;
+}
+
+/*
+ * implements ecc->write_oob()
+ *
+ * the NAND controller cannot write only data or only oob within a codeword,
+ * since ecc is calculated for the combined codeword. we first copy the
+ * entire contents for the last codeword(data + oob), replace the old oob
+ * with the new one in chip->oob_poi, and then write the entire codeword.
+ * this read-copy-write operation results in a slight performance loss.
+ */
+static int qcom_nandc_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
+ int page)
+{
+ struct qcom_nand_host *host = to_qcom_nand_host(chip);
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ u8 *oob = chip->oob_poi;
+ int free_boff;
+ int data_size, oob_size;
+ int ret, status = 0;
+
+ host->use_ecc = true;
+
+ ret = copy_last_cw(host, page);
+ if (ret)
+ return ret;
+
+ clear_read_regs(nandc);
+
+ /* calculate the data and oob size for the last codeword/step */
+ data_size = ecc->size - ((ecc->steps - 1) << 2);
+ oob_size = ecc->steps << 2;
+
+ free_boff = ecc->layout->oobfree[0].offset;
+
+ /* override new oob content to last codeword */
+ memcpy(nandc->data_buffer + data_size, oob + free_boff, oob_size);
+
+ set_address(host, host->cw_size * (ecc->steps - 1), page);
+ update_rw_regs(host, 1, false);
+
+ config_cw_write_pre(nandc);
+ write_data_dma(nandc, FLASH_BUF_ACC, nandc->data_buffer,
+ data_size + oob_size);
+ config_cw_write_post(nandc);
+
+ ret = submit_descs(nandc);
+
+ free_descs(nandc);
+
+ if (ret) {
+ dev_err(nandc->dev, "failure to write oob\n");
+ return -EIO;
+ }
+
+ chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
+
+ status = chip->waitfunc(mtd, chip);
+
+ return status & NAND_STATUS_FAIL ? -EIO : 0;
+}
+
+static int qcom_nandc_block_bad(struct mtd_info *mtd, loff_t ofs)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct qcom_nand_host *host = to_qcom_nand_host(chip);
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ int page, ret, bbpos, bad = 0;
+ u32 flash_status;
+
+ page = (int)(ofs >> chip->page_shift) & chip->pagemask;
+
+ /*
+ * configure registers for a raw sub page read, the address is set to
+ * the beginning of the last codeword, we don't care about reading ecc
+ * portion of oob. we just want the first few bytes from this codeword
+ * that contains the BBM
+ */
+ host->use_ecc = false;
+
+ ret = copy_last_cw(host, page);
+ if (ret)
+ goto err;
+
+ flash_status = le32_to_cpu(nandc->reg_read_buf[0]);
+
+ if (flash_status & (FS_OP_ERR | FS_MPU_ERR)) {
+ dev_warn(nandc->dev, "error when trying to read BBM\n");
+ goto err;
+ }
+
+ bbpos = mtd->writesize - host->cw_size * (ecc->steps - 1);
+
+ bad = nandc->data_buffer[bbpos] != 0xff;
+
+ if (chip->options & NAND_BUSWIDTH_16)
+ bad = bad || (nandc->data_buffer[bbpos + 1] != 0xff);
+err:
+ return bad;
+}
+
+static int qcom_nandc_block_markbad(struct mtd_info *mtd, loff_t ofs)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct qcom_nand_host *host = to_qcom_nand_host(chip);
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ int page, ret, status = 0;
+
+ clear_read_regs(nandc);
+
+ /*
+ * to mark the BBM as bad, we flash the entire last codeword with 0s.
+ * we don't care about the rest of the content in the codeword since
+ * we aren't going to use this block again
+ */
+ memset(nandc->data_buffer, 0x00, host->cw_size);
+
+ page = (int)(ofs >> chip->page_shift) & chip->pagemask;
+
+ /* prepare write */
+ host->use_ecc = false;
+ set_address(host, host->cw_size * (ecc->steps - 1), page);
+ update_rw_regs(host, 1, false);
+
+ config_cw_write_pre(nandc);
+ write_data_dma(nandc, FLASH_BUF_ACC, nandc->data_buffer, host->cw_size);
+ config_cw_write_post(nandc);
+
+ ret = submit_descs(nandc);
+
+ free_descs(nandc);
+
+ if (ret) {
+ dev_err(nandc->dev, "failure to update BBM\n");
+ return -EIO;
+ }
+
+ chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
+
+ status = chip->waitfunc(mtd, chip);
+
+ return status & NAND_STATUS_FAIL ? -EIO : 0;
+}
+
+/*
+ * the three functions below implement chip->read_byte(), chip->read_buf()
+ * and chip->write_buf() respectively. these aren't used for
+ * reading/writing page data, they are used for smaller data like reading
+ * id, status etc
+ */
+static uint8_t qcom_nandc_read_byte(struct mtd_info *mtd)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct qcom_nand_host *host = to_qcom_nand_host(chip);
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ u8 *buf = nandc->data_buffer;
+ u8 ret = 0x0;
+
+ if (host->last_command == NAND_CMD_STATUS) {
+ ret = host->status;
+
+ host->status = NAND_STATUS_READY | NAND_STATUS_WP;
+
+ return ret;
+ }
+
+ if (nandc->buf_start < nandc->buf_count)
+ ret = buf[nandc->buf_start++];
+
+ return ret;
+}
+
+static void qcom_nandc_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ int real_len = min_t(size_t, len, nandc->buf_count - nandc->buf_start);
+
+ memcpy(buf, nandc->data_buffer + nandc->buf_start, real_len);
+ nandc->buf_start += real_len;
+}
+
+static void qcom_nandc_write_buf(struct mtd_info *mtd, const uint8_t *buf,
+ int len)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ int real_len = min_t(size_t, len, nandc->buf_count - nandc->buf_start);
+
+ memcpy(nandc->data_buffer + nandc->buf_start, buf, real_len);
+
+ nandc->buf_start += real_len;
+}
+
+/* we support only one external chip for now */
+static void qcom_nandc_select_chip(struct mtd_info *mtd, int chipnr)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+
+ if (chipnr <= 0)
+ return;
+
+ dev_warn(nandc->dev, "invalid chip select\n");
+}
+
+/*
+ * NAND controller page layout info
+ *
+ * Layout with ECC enabled:
+ *
+ * |----------------------| |---------------------------------|
+ * | xx.......yy| | *********xx.......yy|
+ * | DATA xx..ECC..yy| | DATA **SPARE**xx..ECC..yy|
+ * | (516) xx.......yy| | (516-n*4) **(n*4)**xx.......yy|
+ * | xx.......yy| | *********xx.......yy|
+ * |----------------------| |---------------------------------|
+ * codeword 1,2..n-1 codeword n
+ * <---(528/532 Bytes)--> <-------(528/532 Bytes)--------->
+ *
+ * n = Number of codewords in the page
+ * . = ECC bytes
+ * * = Spare/free bytes
+ * x = Unused byte(s)
+ * y = Reserved byte(s)
+ *
+ * 2K page: n = 4, spare = 16 bytes
+ * 4K page: n = 8, spare = 32 bytes
+ * 8K page: n = 16, spare = 64 bytes
+ *
+ * the qcom nand controller operates at a sub page/codeword level. each
+ * codeword is 528 and 532 bytes for 4 bit and 8 bit ECC modes respectively.
+ * the number of ECC bytes vary based on the ECC strength and the bus width.
+ *
+ * the first n - 1 codewords contains 516 bytes of user data, the remaining
+ * 12/16 bytes consist of ECC and reserved data. The nth codeword contains
+ * both user data and spare(oobavail) bytes that sum up to 516 bytes.
+ *
+ * When we access a page with ECC enabled, the reserved bytes(s) are not
+ * accessible at all. When reading, we fill up these unreadable positions
+ * with 0xffs. When writing, the controller skips writing the inaccessible
+ * bytes.
+ *
+ * Layout with ECC disabled:
+ *
+ * |------------------------------| |---------------------------------------|
+ * | yy xx.......| | bb *********xx.......|
+ * | DATA1 yy DATA2 xx..ECC..| | DATA1 bb DATA2 **SPARE**xx..ECC..|
+ * | (size1) yy (size2) xx.......| | (size1) bb (size2) **(n*4)**xx.......|
+ * | yy xx.......| | bb *********xx.......|
+ * |------------------------------| |---------------------------------------|
+ * codeword 1,2..n-1 codeword n
+ * <-------(528/532 Bytes)------> <-----------(528/532 Bytes)----------->
+ *
+ * n = Number of codewords in the page
+ * . = ECC bytes
+ * * = Spare/free bytes
+ * x = Unused byte(s)
+ * y = Dummy Bad Bock byte(s)
+ * b = Real Bad Block byte(s)
+ * size1/size2 = function of codeword size and 'n'
+ *
+ * when the ECC block is disabled, one reserved byte (or two for 16 bit bus
+ * width) is now accessible. For the first n - 1 codewords, these are dummy Bad
+ * Block Markers. In the last codeword, this position contains the real BBM
+ *
+ * In order to have a consistent layout between RAW and ECC modes, we assume
+ * the following OOB layout arrangement:
+ *
+ * |-----------| |--------------------|
+ * |yyxx.......| |bb*********xx.......|
+ * |yyxx..ECC..| |bb*FREEOOB*xx..ECC..|
+ * |yyxx.......| |bb*********xx.......|
+ * |yyxx.......| |bb*********xx.......|
+ * |-----------| |--------------------|
+ * first n - 1 nth OOB region
+ * OOB regions
+ *
+ * n = Number of codewords in the page
+ * . = ECC bytes
+ * * = FREE OOB bytes
+ * y = Dummy bad block byte(s) (inaccessible when ECC enabled)
+ * x = Unused byte(s)
+ * b = Real bad block byte(s) (inaccessible when ECC enabled)
+ *
+ * This layout is read as is when ECC is disabled. When ECC is enabled, the
+ * inaccessible Bad Block byte(s) are ignored when we write to a page/oob,
+ * and assumed as 0xffs when we read a page/oob. The ECC, unused and
+ * dummy/real bad block bytes are grouped as ecc bytes in nand_ecclayout (i.e,
+ * ecc->bytes is the sum of the three).
+ */
+
+static struct nand_ecclayout *
+qcom_nand_create_layout(struct qcom_nand_host *host)
+{
+ struct nand_chip *chip = &host->chip;
+ struct mtd_info *mtd = nand_to_mtd(chip);
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ struct nand_ecclayout *layout;
+ int i, j, steps, pos = 0, shift = 0;
+
+ layout = devm_kzalloc(nandc->dev, sizeof(*layout), GFP_KERNEL);
+ if (!layout)
+ return NULL;
+
+ steps = mtd->writesize / ecc->size;
+ layout->eccbytes = steps * ecc->bytes;
+
+ layout->oobfree[0].offset = (steps - 1) * ecc->bytes + host->bbm_size;
+ layout->oobfree[0].length = steps << 2;
+
+ /*
+ * the oob bytes in the first n - 1 codewords are all grouped together
+ * in the format:
+ * DUMMY_BBM + UNUSED + ECC
+ */
+ for (i = 0; i < steps - 1; i++) {
+ for (j = 0; j < ecc->bytes; j++)
+ layout->eccpos[pos++] = i * ecc->bytes + j;
+ }
+
+ /*
+ * the oob bytes in the last codeword are grouped in the format:
+ * BBM + FREE OOB + UNUSED + ECC
+ */
+
+ /* fill up the bbm positions */
+ for (j = 0; j < host->bbm_size; j++)
+ layout->eccpos[pos++] = i * ecc->bytes + j;
+
+ /*
+ * fill up the ecc and reserved positions, their indices are offseted
+ * by the free oob region
+ */
+ shift = layout->oobfree[0].length + host->bbm_size;
+
+ for (j = 0; j < (host->ecc_bytes_hw + host->spare_bytes); j++)
+ layout->eccpos[pos++] = i * ecc->bytes + shift + j;
+
+ return layout;
+}
+
+static int qcom_nand_host_setup(struct qcom_nand_host *host)
+{
+ struct nand_chip *chip = &host->chip;
+ struct mtd_info *mtd = nand_to_mtd(chip);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
+ int cwperpage, bad_block_byte;
+ bool wide_bus;
+ int ecc_mode = 1;
+
+ /*
+ * the controller requires each step consists of 512 bytes of data.
+ * bail out if DT has populated a wrong step size.
+ */
+ if (ecc->size != NANDC_STEP_SIZE) {
+ dev_err(nandc->dev, "invalid ecc size\n");
+ return -EINVAL;
+ }
+
+ wide_bus = chip->options & NAND_BUSWIDTH_16 ? true : false;
+
+ if (ecc->strength >= 8) {
+ /* 8 bit ECC defaults to BCH ECC on all platforms */
+ host->bch_enabled = true;
+ ecc_mode = 1;
+
+ if (wide_bus) {
+ host->ecc_bytes_hw = 14;
+ host->spare_bytes = 0;
+ host->bbm_size = 2;
+ } else {
+ host->ecc_bytes_hw = 13;
+ host->spare_bytes = 2;
+ host->bbm_size = 1;
+ }
+ } else {
+ /*
+ * if the controller supports BCH for 4 bit ECC, the controller
+ * uses lesser bytes for ECC. If RS is used, the ECC bytes is
+ * always 10 bytes
+ */
+ if (nandc->ecc_modes & ECC_BCH_4BIT) {
+ /* BCH */
+ host->bch_enabled = true;
+ ecc_mode = 0;
+
+ if (wide_bus) {
+ host->ecc_bytes_hw = 8;
+ host->spare_bytes = 2;
+ host->bbm_size = 2;
+ } else {
+ host->ecc_bytes_hw = 7;
+ host->spare_bytes = 4;
+ host->bbm_size = 1;
+ }
+ } else {
+ /* RS */
+ host->ecc_bytes_hw = 10;
+
+ if (wide_bus) {
+ host->spare_bytes = 0;
+ host->bbm_size = 2;
+ } else {
+ host->spare_bytes = 1;
+ host->bbm_size = 1;
+ }
+ }
+ }
+
+ /*
+ * we consider ecc->bytes as the sum of all the non-data content in a
+ * step. It gives us a clean representation of the oob area (even if
+ * all the bytes aren't used for ECC).It is always 16 bytes for 8 bit
+ * ECC and 12 bytes for 4 bit ECC
+ */
+ ecc->bytes = host->ecc_bytes_hw + host->spare_bytes + host->bbm_size;
+
+ ecc->read_page = qcom_nandc_read_page;
+ ecc->read_page_raw = qcom_nandc_read_page_raw;
+ ecc->read_oob = qcom_nandc_read_oob;
+ ecc->write_page = qcom_nandc_write_page;
+ ecc->write_page_raw = qcom_nandc_write_page_raw;
+ ecc->write_oob = qcom_nandc_write_oob;
+
+ ecc->mode = NAND_ECC_HW;
+
+ ecc->layout = qcom_nand_create_layout(host);
+ if (!ecc->layout)
+ return -ENOMEM;
+
+ cwperpage = mtd->writesize / ecc->size;
+
+ /*
+ * DATA_UD_BYTES varies based on whether the read/write command protects
+ * spare data with ECC too. We protect spare data by default, so we set
+ * it to main + spare data, which are 512 and 4 bytes respectively.
+ */
+ host->cw_data = 516;
+
+ /*
+ * total bytes in a step, either 528 bytes for 4 bit ECC, or 532 bytes
+ * for 8 bit ECC
+ */
+ host->cw_size = host->cw_data + ecc->bytes;
+
+ if (ecc->bytes * (mtd->writesize / ecc->size) > mtd->oobsize) {
+ dev_err(nandc->dev, "ecc data doesn't fit in OOB area\n");
+ return -EINVAL;
+ }
+
+ bad_block_byte = mtd->writesize - host->cw_size * (cwperpage - 1) + 1;
+
+ host->cfg0 = (cwperpage - 1) << CW_PER_PAGE
+ | host->cw_data << UD_SIZE_BYTES
+ | 0 << DISABLE_STATUS_AFTER_WRITE
+ | 5 << NUM_ADDR_CYCLES
+ | host->ecc_bytes_hw << ECC_PARITY_SIZE_BYTES_RS
+ | 0 << STATUS_BFR_READ
+ | 1 << SET_RD_MODE_AFTER_STATUS
+ | host->spare_bytes << SPARE_SIZE_BYTES;
+
+ host->cfg1 = 7 << NAND_RECOVERY_CYCLES
+ | 0 << CS_ACTIVE_BSY
+ | bad_block_byte << BAD_BLOCK_BYTE_NUM
+ | 0 << BAD_BLOCK_IN_SPARE_AREA
+ | 2 << WR_RD_BSY_GAP
+ | wide_bus << WIDE_FLASH
+ | host->bch_enabled << ENABLE_BCH_ECC;
+
+ host->cfg0_raw = (cwperpage - 1) << CW_PER_PAGE
+ | host->cw_size << UD_SIZE_BYTES
+ | 5 << NUM_ADDR_CYCLES
+ | 0 << SPARE_SIZE_BYTES;
+
+ host->cfg1_raw = 7 << NAND_RECOVERY_CYCLES
+ | 0 << CS_ACTIVE_BSY
+ | 17 << BAD_BLOCK_BYTE_NUM
+ | 1 << BAD_BLOCK_IN_SPARE_AREA
+ | 2 << WR_RD_BSY_GAP
+ | wide_bus << WIDE_FLASH
+ | 1 << DEV0_CFG1_ECC_DISABLE;
+
+ host->ecc_bch_cfg = host->bch_enabled << ECC_CFG_ECC_DISABLE
+ | 0 << ECC_SW_RESET
+ | host->cw_data << ECC_NUM_DATA_BYTES
+ | 1 << ECC_FORCE_CLK_OPEN
+ | ecc_mode << ECC_MODE
+ | host->ecc_bytes_hw << ECC_PARITY_SIZE_BYTES_BCH;
+
+ host->ecc_buf_cfg = 0x203 << NUM_STEPS;
+
+ host->clrflashstatus = FS_READY_BSY_N;
+ host->clrreadstatus = 0xc0;
+
+ dev_dbg(nandc->dev,
+ "cfg0 %x cfg1 %x ecc_buf_cfg %x ecc_bch cfg %x cw_size %d cw_data %d strength %d parity_bytes %d steps %d\n",
+ host->cfg0, host->cfg1, host->ecc_buf_cfg, host->ecc_bch_cfg,
+ host->cw_size, host->cw_data, ecc->strength, ecc->bytes,
+ cwperpage);
+
+ return 0;
+}
+
+static int qcom_nandc_alloc(struct qcom_nand_controller *nandc)
+{
+ int ret;
+
+ ret = dma_set_coherent_mask(nandc->dev, DMA_BIT_MASK(32));
+ if (ret) {
+ dev_err(nandc->dev, "failed to set DMA mask\n");
+ return ret;
+ }
+
+ /*
+ * we use the internal buffer for reading ONFI params, reading small
+ * data like ID and status, and preforming read-copy-write operations
+ * when writing to a codeword partially. 532 is the maximum possible
+ * size of a codeword for our nand controller
+ */
+ nandc->buf_size = 532;
+
+ nandc->data_buffer = devm_kzalloc(nandc->dev, nandc->buf_size,
+ GFP_KERNEL);
+ if (!nandc->data_buffer)
+ return -ENOMEM;
+
+ nandc->regs = devm_kzalloc(nandc->dev, sizeof(*nandc->regs),
+ GFP_KERNEL);
+ if (!nandc->regs)
+ return -ENOMEM;
+
+ nandc->reg_read_buf = devm_kzalloc(nandc->dev,
+ MAX_REG_RD * sizeof(*nandc->reg_read_buf),
+ GFP_KERNEL);
+ if (!nandc->reg_read_buf)
+ return -ENOMEM;
+
+ nandc->chan = dma_request_slave_channel(nandc->dev, "rxtx");
+ if (!nandc->chan) {
+ dev_err(nandc->dev, "failed to request slave channel\n");
+ return -ENODEV;
+ }
+
+ INIT_LIST_HEAD(&nandc->desc_list);
+ INIT_LIST_HEAD(&nandc->host_list);
+
+ spin_lock_init(&nandc->controller.lock);
+ init_waitqueue_head(&nandc->controller.wq);
+
+ return 0;
+}
+
+static void qcom_nandc_unalloc(struct qcom_nand_controller *nandc)
+{
+ dma_release_channel(nandc->chan);
+}
+
+/* one time setup of a few nand controller registers */
+static int qcom_nandc_setup(struct qcom_nand_controller *nandc)
+{
+ /* kill onenand */
+ nandc_write(nandc, SFLASHC_BURST_CFG, 0);
+
+ /* enable ADM DMA */
+ nandc_write(nandc, NAND_FLASH_CHIP_SELECT, DM_EN);
+
+ /* save the original values of these registers */
+ nandc->cmd1 = nandc_read(nandc, NAND_DEV_CMD1);
+ nandc->vld = nandc_read(nandc, NAND_DEV_CMD_VLD);
+
+ return 0;
+}
+
+static int qcom_nand_host_init(struct qcom_nand_controller *nandc,
+ struct qcom_nand_host *host,
+ struct device_node *dn)
+{
+ struct nand_chip *chip = &host->chip;
+ struct mtd_info *mtd = nand_to_mtd(chip);
+ struct device *dev = nandc->dev;
+ int ret;
+
+ ret = of_property_read_u32(dn, "reg", &host->cs);
+ if (ret) {
+ dev_err(dev, "can't get chip-select\n");
+ return -ENXIO;
+ }
+
+ nand_set_flash_node(chip, dn);
+ mtd->name = devm_kasprintf(dev, GFP_KERNEL, "qcom_nand.%d", host->cs);
+ mtd->owner = THIS_MODULE;
+ mtd->dev.parent = dev;
+
+ chip->cmdfunc = qcom_nandc_command;
+ chip->select_chip = qcom_nandc_select_chip;
+ chip->read_byte = qcom_nandc_read_byte;
+ chip->read_buf = qcom_nandc_read_buf;
+ chip->write_buf = qcom_nandc_write_buf;
+
+ /*
+ * the bad block marker is readable only when we read the last codeword
+ * of a page with ECC disabled. currently, the nand_base and nand_bbt
+ * helpers don't allow us to read BB from a nand chip with ECC
+ * disabled (MTD_OPS_PLACE_OOB is set by default). use the block_bad
+ * and block_markbad helpers until we permanently switch to using
+ * MTD_OPS_RAW for all drivers (with the help of badblockbits)
+ */
+ chip->block_bad = qcom_nandc_block_bad;
+ chip->block_markbad = qcom_nandc_block_markbad;
+
+ chip->controller = &nandc->controller;
+ chip->options |= NAND_NO_SUBPAGE_WRITE | NAND_USE_BOUNCE_BUFFER |
+ NAND_SKIP_BBTSCAN;
+
+ /* set up initial status value */
+ host->status = NAND_STATUS_READY | NAND_STATUS_WP;
+
+ ret = nand_scan_ident(mtd, 1, NULL);
+ if (ret)
+ return ret;
+
+ ret = qcom_nand_host_setup(host);
+ if (ret)
+ return ret;
+
+ ret = nand_scan_tail(mtd);
+ if (ret)
+ return ret;
+
+ return mtd_device_register(mtd, NULL, 0);
+}
+
+/* parse custom DT properties here */
+static int qcom_nandc_parse_dt(struct platform_device *pdev)
+{
+ struct qcom_nand_controller *nandc = platform_get_drvdata(pdev);
+ struct device_node *np = nandc->dev->of_node;
+ int ret;
+
+ ret = of_property_read_u32(np, "qcom,cmd-crci", &nandc->cmd_crci);
+ if (ret) {
+ dev_err(nandc->dev, "command CRCI unspecified\n");
+ return ret;
+ }
+
+ ret = of_property_read_u32(np, "qcom,data-crci", &nandc->data_crci);
+ if (ret) {
+ dev_err(nandc->dev, "data CRCI unspecified\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int qcom_nandc_probe(struct platform_device *pdev)
+{
+ struct qcom_nand_controller *nandc;
+ struct qcom_nand_host *host;
+ const void *dev_data;
+ struct device *dev = &pdev->dev;
+ struct device_node *dn = dev->of_node, *child;
+ struct resource *res;
+ int ret;
+
+ nandc = devm_kzalloc(&pdev->dev, sizeof(*nandc), GFP_KERNEL);
+ if (!nandc)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, nandc);
+ nandc->dev = dev;
+
+ dev_data = of_device_get_match_data(dev);
+ if (!dev_data) {
+ dev_err(&pdev->dev, "failed to get device data\n");
+ return -ENODEV;
+ }
+
+ nandc->ecc_modes = (unsigned long)dev_data;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ nandc->base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(nandc->base))
+ return PTR_ERR(nandc->base);
+
+ nandc->base_dma = phys_to_dma(dev, (phys_addr_t)res->start);
+
+ nandc->core_clk = devm_clk_get(dev, "core");
+ if (IS_ERR(nandc->core_clk))
+ return PTR_ERR(nandc->core_clk);
+
+ nandc->aon_clk = devm_clk_get(dev, "aon");
+ if (IS_ERR(nandc->aon_clk))
+ return PTR_ERR(nandc->aon_clk);
+
+ ret = qcom_nandc_parse_dt(pdev);
+ if (ret)
+ return ret;
+
+ ret = qcom_nandc_alloc(nandc);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(nandc->core_clk);
+ if (ret)
+ goto err_core_clk;
+
+ ret = clk_prepare_enable(nandc->aon_clk);
+ if (ret)
+ goto err_aon_clk;
+
+ ret = qcom_nandc_setup(nandc);
+ if (ret)
+ goto err_setup;
+
+ for_each_available_child_of_node(dn, child) {
+ if (of_device_is_compatible(child, "qcom,nandcs")) {
+ host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
+ if (!host) {
+ of_node_put(child);
+ ret = -ENOMEM;
+ goto err_cs_init;
+ }
+
+ ret = qcom_nand_host_init(nandc, host, child);
+ if (ret) {
+ devm_kfree(dev, host);
+ continue;
+ }
+
+ list_add_tail(&host->node, &nandc->host_list);
+ }
+ }
+
+ if (list_empty(&nandc->host_list)) {
+ ret = -ENODEV;
+ goto err_cs_init;
+ }
+
+ return 0;
+
+err_cs_init:
+ list_for_each_entry(host, &nandc->host_list, node)
+ nand_release(nand_to_mtd(&host->chip));
+err_setup:
+ clk_disable_unprepare(nandc->aon_clk);
+err_aon_clk:
+ clk_disable_unprepare(nandc->core_clk);
+err_core_clk:
+ qcom_nandc_unalloc(nandc);
+
+ return ret;
+}
+
+static int qcom_nandc_remove(struct platform_device *pdev)
+{
+ struct qcom_nand_controller *nandc = platform_get_drvdata(pdev);
+ struct qcom_nand_host *host;
+
+ list_for_each_entry(host, &nandc->host_list, node)
+ nand_release(nand_to_mtd(&host->chip));
+
+ qcom_nandc_unalloc(nandc);
+
+ clk_disable_unprepare(nandc->aon_clk);
+ clk_disable_unprepare(nandc->core_clk);
+
+ return 0;
+}
+
+#define EBI2_NANDC_ECC_MODES (ECC_RS_4BIT | ECC_BCH_8BIT)
+
+/*
+ * data will hold a struct pointer containing more differences once we support
+ * more controller variants
+ */
+static const struct of_device_id qcom_nandc_of_match[] = {
+ { .compatible = "qcom,ipq806x-nand",
+ .data = (void *)EBI2_NANDC_ECC_MODES,
+ },
+ {}
+};
+MODULE_DEVICE_TABLE(of, qcom_nandc_of_match);
+
+static struct platform_driver qcom_nandc_driver = {
+ .driver = {
+ .name = "qcom-nandc",
+ .of_match_table = qcom_nandc_of_match,
+ },
+ .probe = qcom_nandc_probe,
+ .remove = qcom_nandc_remove,
+};
+module_platform_driver(qcom_nandc_driver);
+
+MODULE_AUTHOR("Archit Taneja <architt@codeaurora.org>");
+MODULE_DESCRIPTION("Qualcomm NAND Controller driver");
+MODULE_LICENSE("GPL v2");