diff options
Diffstat (limited to 'drivers/mtd/nand/qcom_nandc.c')
| -rw-r--r-- | drivers/mtd/nand/qcom_nandc.c | 2223 |
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 ®s->cmd; + case NAND_ADDR0: + return ®s->addr0; + case NAND_ADDR1: + return ®s->addr1; + case NAND_FLASH_CHIP_SELECT: + return ®s->chip_sel; + case NAND_EXEC_CMD: + return ®s->exec; + case NAND_FLASH_STATUS: + return ®s->clrflashstatus; + case NAND_DEV0_CFG0: + return ®s->cfg0; + case NAND_DEV0_CFG1: + return ®s->cfg1; + case NAND_DEV0_ECC_CFG: + return ®s->ecc_bch_cfg; + case NAND_READ_STATUS: + return ®s->clrreadstatus; + case NAND_DEV_CMD1: + return ®s->cmd1; + case NAND_DEV_CMD1_RESTORE: + return ®s->orig_cmd1; + case NAND_DEV_CMD_VLD: + return ®s->vld; + case NAND_DEV_CMD_VLD_RESTORE: + return ®s->orig_vld; + case NAND_EBI2_ECC_BUF_CFG: + return ®s->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"); |