Re: [PATCH] mtd: rawnand: brcmnand: Initial exec_op implementation
From: Miquel Raynal
Date: Fri Sep 22 2023 - 10:24:40 EST
Hello,
dregan@xxxxxxxx wrote on Wed, 13 Sep 2023 04:24:41 +0200:
> Initial exec_op implementation for Broadcom STB, Broadband and iProc SoC
> This adds exec_op and removes the legacy interface.
Thanks a lot for the conversion, a few comments below.
> Signed-off-by: David Regan <dregan@xxxxxxxx>
> ---
> drivers/mtd/nand/raw/brcmnand/brcmnand.c | 384 ++++++++++-------------
> 1 file changed, 161 insertions(+), 223 deletions(-)
>
> diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> index 440bef477930..b075dade4129 100644
> --- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> +++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> @@ -625,6 +625,8 @@ enum {
> /* Only for v7.2 */
> #define ACC_CONTROL_ECC_EXT_SHIFT 13
>
> +static u8 brcmnand_status(struct brcmnand_host *host);
> +
> static inline bool brcmnand_non_mmio_ops(struct brcmnand_controller *ctrl)
> {
> #if IS_ENABLED(CONFIG_MTD_NAND_BRCMNAND_BCMA)
> @@ -1022,19 +1024,6 @@ static inline int brcmnand_sector_1k_shift(struct brcmnand_controller *ctrl)
> return -1;
> }
>
> -static int brcmnand_get_sector_size_1k(struct brcmnand_host *host)
> -{
> - struct brcmnand_controller *ctrl = host->ctrl;
> - int shift = brcmnand_sector_1k_shift(ctrl);
> - u16 acc_control_offs = brcmnand_cs_offset(ctrl, host->cs,
> - BRCMNAND_CS_ACC_CONTROL);
> -
> - if (shift < 0)
> - return 0;
> -
> - return (nand_readreg(ctrl, acc_control_offs) >> shift) & 0x1;
> -}
> -
> static void brcmnand_set_sector_size_1k(struct brcmnand_host *host, int val)
> {
> struct brcmnand_controller *ctrl = host->ctrl;
> @@ -1387,7 +1376,8 @@ static void brcmnand_wp(struct mtd_info *mtd, int wp)
> return;
>
> brcmnand_set_wp(ctrl, wp);
> - nand_status_op(chip, NULL);
> + /* force controller operation to update internal copy of NAND chip status */
> + brcmnand_status(host);
> /* NAND_STATUS_WP 0x00 = protected, 0x80 = not protected */
> ret = bcmnand_ctrl_poll_status(ctrl,
> NAND_CTRL_RDY |
> @@ -1643,16 +1633,6 @@ static void brcmnand_send_cmd(struct brcmnand_host *host, int cmd)
> cmd << brcmnand_cmd_shift(ctrl));
> }
>
> -/***********************************************************************
> - * NAND MTD API: read/program/erase
> - ***********************************************************************/
> -
> -static void brcmnand_cmd_ctrl(struct nand_chip *chip, int dat,
> - unsigned int ctrl)
> -{
> - /* intentionally left blank */
> -}
> -
> static bool brcmstb_nand_wait_for_completion(struct nand_chip *chip)
> {
> struct brcmnand_host *host = nand_get_controller_data(chip);
> @@ -1703,6 +1683,17 @@ static int brcmnand_waitfunc(struct nand_chip *chip)
> INTFC_FLASH_STATUS;
> }
>
> +static u8 brcmnand_status(struct brcmnand_host *host)
> +{
> + struct nand_chip *chip = &host->chip;
> + struct mtd_info *mtd = nand_to_mtd(chip);
> +
> + brcmnand_set_cmd_addr(mtd, 0);
> + brcmnand_send_cmd(host, CMD_STATUS_READ);
> +
> + return brcmnand_waitfunc(chip);
> +}
> +
> enum {
> LLOP_RE = BIT(16),
> LLOP_WE = BIT(17),
> @@ -1752,190 +1743,6 @@ static int brcmnand_low_level_op(struct brcmnand_host *host,
> return brcmnand_waitfunc(chip);
> }
>
> -static void brcmnand_cmdfunc(struct nand_chip *chip, unsigned command,
> - int column, int page_addr)
> -{
> - struct mtd_info *mtd = nand_to_mtd(chip);
> - struct brcmnand_host *host = nand_get_controller_data(chip);
> - struct brcmnand_controller *ctrl = host->ctrl;
> - u64 addr = (u64)page_addr << chip->page_shift;
> - int native_cmd = 0;
> -
> - if (command == NAND_CMD_READID || command == NAND_CMD_PARAM ||
> - command == NAND_CMD_RNDOUT)
> - addr = (u64)column;
> - /* Avoid propagating a negative, don't-care address */
> - else if (page_addr < 0)
> - addr = 0;
> -
> - dev_dbg(ctrl->dev, "cmd 0x%x addr 0x%llx\n", command,
> - (unsigned long long)addr);
> -
> - host->last_cmd = command;
> - host->last_byte = 0;
> - host->last_addr = addr;
> -
> - switch (command) {
> - case NAND_CMD_RESET:
> - native_cmd = CMD_FLASH_RESET;
> - break;
> - case NAND_CMD_STATUS:
> - native_cmd = CMD_STATUS_READ;
> - break;
> - case NAND_CMD_READID:
> - native_cmd = CMD_DEVICE_ID_READ;
> - break;
> - case NAND_CMD_READOOB:
> - native_cmd = CMD_SPARE_AREA_READ;
> - break;
> - case NAND_CMD_ERASE1:
> - native_cmd = CMD_BLOCK_ERASE;
> - brcmnand_wp(mtd, 0);
> - break;
> - case NAND_CMD_PARAM:
> - native_cmd = CMD_PARAMETER_READ;
> - break;
> - case NAND_CMD_SET_FEATURES:
> - case NAND_CMD_GET_FEATURES:
> - brcmnand_low_level_op(host, LL_OP_CMD, command, false);
> - brcmnand_low_level_op(host, LL_OP_ADDR, column, false);
> - break;
> - case NAND_CMD_RNDOUT:
> - native_cmd = CMD_PARAMETER_CHANGE_COL;
> - addr &= ~((u64)(FC_BYTES - 1));
> - /*
> - * HW quirk: PARAMETER_CHANGE_COL requires SECTOR_SIZE_1K=0
> - * NB: hwcfg.sector_size_1k may not be initialized yet
> - */
> - if (brcmnand_get_sector_size_1k(host)) {
> - host->hwcfg.sector_size_1k =
> - brcmnand_get_sector_size_1k(host);
> - brcmnand_set_sector_size_1k(host, 0);
> - }
> - break;
> - }
> -
> - if (!native_cmd)
> - return;
> -
> - brcmnand_set_cmd_addr(mtd, addr);
> - brcmnand_send_cmd(host, native_cmd);
> - brcmnand_waitfunc(chip);
> -
> - if (native_cmd == CMD_PARAMETER_READ ||
> - native_cmd == CMD_PARAMETER_CHANGE_COL) {
> - /* Copy flash cache word-wise */
> - u32 *flash_cache = (u32 *)ctrl->flash_cache;
> - int i;
> -
> - brcmnand_soc_data_bus_prepare(ctrl->soc, true);
> -
> - /*
> - * Must cache the FLASH_CACHE now, since changes in
> - * SECTOR_SIZE_1K may invalidate it
> - */
> - for (i = 0; i < FC_WORDS; i++)
> - /*
> - * Flash cache is big endian for parameter pages, at
> - * least on STB SoCs
> - */
> - flash_cache[i] = be32_to_cpu(brcmnand_read_fc(ctrl, i));
> -
> - brcmnand_soc_data_bus_unprepare(ctrl->soc, true);
> -
> - /* Cleanup from HW quirk: restore SECTOR_SIZE_1K */
> - if (host->hwcfg.sector_size_1k)
> - brcmnand_set_sector_size_1k(host,
> - host->hwcfg.sector_size_1k);
> - }
> -
> - /* Re-enable protection is necessary only after erase */
> - if (command == NAND_CMD_ERASE1)
> - brcmnand_wp(mtd, 1);
> -}
> -
> -static uint8_t brcmnand_read_byte(struct nand_chip *chip)
> -{
> - struct brcmnand_host *host = nand_get_controller_data(chip);
> - struct brcmnand_controller *ctrl = host->ctrl;
> - uint8_t ret = 0;
> - int addr, offs;
> -
> - switch (host->last_cmd) {
> - case NAND_CMD_READID:
> - if (host->last_byte < 4)
> - ret = brcmnand_read_reg(ctrl, BRCMNAND_ID) >>
> - (24 - (host->last_byte << 3));
> - else if (host->last_byte < 8)
> - ret = brcmnand_read_reg(ctrl, BRCMNAND_ID_EXT) >>
> - (56 - (host->last_byte << 3));
> - break;
> -
> - case NAND_CMD_READOOB:
> - ret = oob_reg_read(ctrl, host->last_byte);
> - break;
> -
> - case NAND_CMD_STATUS:
> - ret = brcmnand_read_reg(ctrl, BRCMNAND_INTFC_STATUS) &
> - INTFC_FLASH_STATUS;
> - if (wp_on) /* hide WP status */
> - ret |= NAND_STATUS_WP;
> - break;
> -
> - case NAND_CMD_PARAM:
> - case NAND_CMD_RNDOUT:
> - addr = host->last_addr + host->last_byte;
> - offs = addr & (FC_BYTES - 1);
> -
> - /* At FC_BYTES boundary, switch to next column */
> - if (host->last_byte > 0 && offs == 0)
> - nand_change_read_column_op(chip, addr, NULL, 0, false);
> -
> - ret = ctrl->flash_cache[offs];
> - break;
> - case NAND_CMD_GET_FEATURES:
> - if (host->last_byte >= ONFI_SUBFEATURE_PARAM_LEN) {
> - ret = 0;
> - } else {
> - bool last = host->last_byte ==
> - ONFI_SUBFEATURE_PARAM_LEN - 1;
> - brcmnand_low_level_op(host, LL_OP_RD, 0, last);
> - ret = brcmnand_read_reg(ctrl, BRCMNAND_LL_RDATA) & 0xff;
> - }
> - }
> -
> - dev_dbg(ctrl->dev, "read byte = 0x%02x\n", ret);
> - host->last_byte++;
> -
> - return ret;
> -}
> -
> -static void brcmnand_read_buf(struct nand_chip *chip, uint8_t *buf, int len)
> -{
> - int i;
> -
> - for (i = 0; i < len; i++, buf++)
> - *buf = brcmnand_read_byte(chip);
> -}
> -
> -static void brcmnand_write_buf(struct nand_chip *chip, const uint8_t *buf,
> - int len)
> -{
> - int i;
> - struct brcmnand_host *host = nand_get_controller_data(chip);
> -
> - switch (host->last_cmd) {
> - case NAND_CMD_SET_FEATURES:
> - for (i = 0; i < len; i++)
> - brcmnand_low_level_op(host, LL_OP_WR, buf[i],
> - (i + 1) == len);
> - break;
> - default:
> - BUG();
> - break;
> - }
> -}
> -
> /*
> * Kick EDU engine
> */
> @@ -2345,8 +2152,9 @@ static int brcmnand_read_page(struct nand_chip *chip, uint8_t *buf,
> struct mtd_info *mtd = nand_to_mtd(chip);
> struct brcmnand_host *host = nand_get_controller_data(chip);
> u8 *oob = oob_required ? (u8 *)chip->oob_poi : NULL;
> + u64 addr = (u64)page << chip->page_shift;
>
> - nand_read_page_op(chip, page, 0, NULL, 0);
> + host->last_addr = addr;
>
> return brcmnand_read(mtd, chip, host->last_addr,
> mtd->writesize >> FC_SHIFT, (u32 *)buf, oob);
> @@ -2359,8 +2167,9 @@ static int brcmnand_read_page_raw(struct nand_chip *chip, uint8_t *buf,
> struct mtd_info *mtd = nand_to_mtd(chip);
> u8 *oob = oob_required ? (u8 *)chip->oob_poi : NULL;
> int ret;
> + u64 addr = (u64)page << chip->page_shift;
>
> - nand_read_page_op(chip, page, 0, NULL, 0);
> + host->last_addr = addr;
>
> brcmnand_set_ecc_enabled(host, 0);
> ret = brcmnand_read(mtd, chip, host->last_addr,
> @@ -2468,11 +2277,11 @@ static int brcmnand_write_page(struct nand_chip *chip, const uint8_t *buf,
> struct mtd_info *mtd = nand_to_mtd(chip);
> struct brcmnand_host *host = nand_get_controller_data(chip);
> void *oob = oob_required ? chip->oob_poi : NULL;
> + u64 addr = (u64)page << chip->page_shift;
>
> - nand_prog_page_begin_op(chip, page, 0, NULL, 0);
> - brcmnand_write(mtd, chip, host->last_addr, (const u32 *)buf, oob);
> + host->last_addr = addr;
>
> - return nand_prog_page_end_op(chip);
> + return brcmnand_write(mtd, chip, host->last_addr, (const u32 *)buf, oob);
> }
>
> static int brcmnand_write_page_raw(struct nand_chip *chip, const uint8_t *buf,
> @@ -2481,13 +2290,15 @@ static int brcmnand_write_page_raw(struct nand_chip *chip, const uint8_t *buf,
> struct mtd_info *mtd = nand_to_mtd(chip);
> struct brcmnand_host *host = nand_get_controller_data(chip);
> void *oob = oob_required ? chip->oob_poi : NULL;
> + u64 addr = (u64)page << chip->page_shift;
> + int ret = 0;
>
> - nand_prog_page_begin_op(chip, page, 0, NULL, 0);
> + host->last_addr = addr;
> brcmnand_set_ecc_enabled(host, 0);
> - brcmnand_write(mtd, chip, host->last_addr, (const u32 *)buf, oob);
> + ret = brcmnand_write(mtd, chip, host->last_addr, (const u32 *)buf, oob);
> brcmnand_set_ecc_enabled(host, 1);
>
> - return nand_prog_page_end_op(chip);
> + return ret;
> }
>
> static int brcmnand_write_oob(struct nand_chip *chip, int page)
> @@ -2511,6 +2322,139 @@ static int brcmnand_write_oob_raw(struct nand_chip *chip, int page)
> return ret;
> }
>
> +static void brcmnand_exec_instr(struct brcmnand_host *host,
> + const struct nand_op_instr *instr,
> + bool last_op)
> +{
> + struct brcmnand_controller *ctrl = host->ctrl;
> + unsigned int i;
> + const u8 *out;
> + u8 *in;
> +
> + bcmnand_ctrl_poll_status(ctrl, NAND_CTRL_RDY, NAND_CTRL_RDY, 0);
> +
> + switch (instr->type) {
> + case NAND_OP_CMD_INSTR:
> + brcmnand_low_level_op(host, LL_OP_CMD,
> + instr->ctx.cmd.opcode, last_op);
> + break;
> +
> + case NAND_OP_ADDR_INSTR:
> + for (i = 0; i < instr->ctx.addr.naddrs; i++)
> + brcmnand_low_level_op(host, LL_OP_ADDR,
> + instr->ctx.addr.addrs[i],
> + last_op);
> + break;
> +
> + case NAND_OP_DATA_IN_INSTR:
> + in = instr->ctx.data.buf.in;
> + for (i = 0; i < instr->ctx.data.len; i++) {
> + brcmnand_low_level_op(host, LL_OP_RD, 0, last_op);
> + in[i] = brcmnand_read_reg(host->ctrl,
> + BRCMNAND_LL_RDATA);
> + }
> + break;
> +
> + case NAND_OP_DATA_OUT_INSTR:
> + out = instr->ctx.data.buf.out;
> + for (i = 0; i < instr->ctx.data.len; i++)
> + brcmnand_low_level_op(host, LL_OP_WR, out[i], last_op);
> + break;
> +
> + default:
Should probably return an error.
> + break;
> + }
> +}
> +
> +static int brcmnand_parser_exec_matched_op(struct nand_chip *chip,
> + const struct nand_subop *subop)
> +{
> + struct brcmnand_host *host = nand_get_controller_data(chip);
> + struct mtd_info *mtd = nand_to_mtd(chip);
> + const struct nand_op_instr *instr = &subop->instrs[0];
> + unsigned int i;
> + int ret = 0;
> +
> + static int erase; /* will initialize to zero */
> + static int status; /* will initialize to zero */
Looks really suspicious, I believe you should rework your
implementation to avoid static variables here.
> +
> + for (i = 0; i < subop->ninstrs; i++) {
> + instr = &subop->instrs[i];
> +
> + if ((instr->type == NAND_OP_CMD_INSTR) &&
> + (instr->ctx.cmd.opcode == NAND_CMD_STATUS))
> + status = 1;
> + else if (status && (instr->type == NAND_OP_DATA_IN_INSTR)) {
> + /*
> + * need to fake the nand device write protect because nand_base does a
> + * nand_check_wp which calls nand_status_op NAND_CMD_STATUS which checks
> + * that the nand is not write protected before an operation starts.
> + * The problem with this is it's done outside exec_op so the nand is
> + * write protected and this check will fail until the write or erase
> + * or write back operation actually happens where we turn off wp.
> + */
If there is a problem with the core it needs to be handled in the core,
not workarounded here. The whole logic with the status property seems
really wrong.
> + u8 *in;
> +
> + status = 0;
> +
> + instr = &subop->instrs[i];
> + in = instr->ctx.data.buf.in;
> + in[0] = brcmnand_status(host) | NAND_STATUS_WP; /* hide WP status */
> + } else { /* otherwise pass to low level implementation */
> + if ((instr->type == NAND_OP_CMD_INSTR) &&
> + (instr->ctx.cmd.opcode == NAND_CMD_RESET)) {
> + erase = 0;
> + status = 0;
> + }
> +
> + if (erase) {
> + erase = 0;
> + brcmnand_wp(mtd, 1);
> + }
> +
> + if ((instr->type == NAND_OP_CMD_INSTR) &&
> + (instr->ctx.cmd.opcode == NAND_CMD_ERASE1))
> + brcmnand_wp(mtd, 0);
> +
> + if ((instr->type == NAND_OP_CMD_INSTR) &&
> + (instr->ctx.cmd.opcode == NAND_CMD_ERASE2))
> + erase = 1;
> +
> + brcmnand_exec_instr(host, instr, i == (subop->ninstrs - 1));
> + }
> + }
> +
> + return ret;
> +}
> +
> +static const struct nand_op_parser brcmnand_op_parser = NAND_OP_PARSER(
> + /* false means the element MUST match,
> + * true means it does not have to match, catch all patterns
> + */
I believe the comment is not really useful here?
> + NAND_OP_PARSER_PATTERN(
> + brcmnand_parser_exec_matched_op,
> + NAND_OP_PARSER_PAT_CMD_ELEM(true)),
> + NAND_OP_PARSER_PATTERN(
> + brcmnand_parser_exec_matched_op,
> + NAND_OP_PARSER_PAT_ADDR_ELEM(true, 8)),
> + NAND_OP_PARSER_PATTERN(
> + brcmnand_parser_exec_matched_op,
> + NAND_OP_PARSER_PAT_DATA_IN_ELEM(true, 8192)),
> + NAND_OP_PARSER_PATTERN(
> + brcmnand_parser_exec_matched_op,
> + NAND_OP_PARSER_PAT_DATA_OUT_ELEM(true, 8192)),
> + NAND_OP_PARSER_PATTERN(
> + brcmnand_parser_exec_matched_op,
> + NAND_OP_PARSER_PAT_WAITRDY_ELEM(true)),
> +);
> +
> +static int brcmnand_exec_op(struct nand_chip *chip,
> + const struct nand_operation *op,
> + bool check_only)
> +{
> + return nand_op_parser_exec_op(chip, &brcmnand_op_parser, op, check_only);
> +}
> +
> /***********************************************************************
> * Per-CS setup (1 NAND device)
> ***********************************************************************/
> @@ -2821,6 +2765,7 @@ static int brcmnand_attach_chip(struct nand_chip *chip)
>
> static const struct nand_controller_ops brcmnand_controller_ops = {
> .attach_chip = brcmnand_attach_chip,
> + .exec_op = brcmnand_exec_op,
> };
>
> static int brcmnand_init_cs(struct brcmnand_host *host,
> @@ -2845,13 +2790,6 @@ static int brcmnand_init_cs(struct brcmnand_host *host,
> mtd->owner = THIS_MODULE;
> mtd->dev.parent = dev;
>
> - chip->legacy.cmd_ctrl = brcmnand_cmd_ctrl;
> - chip->legacy.cmdfunc = brcmnand_cmdfunc;
> - chip->legacy.waitfunc = brcmnand_waitfunc;
> - chip->legacy.read_byte = brcmnand_read_byte;
> - chip->legacy.read_buf = brcmnand_read_buf;
> - chip->legacy.write_buf = brcmnand_write_buf;
> -
> chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
> chip->ecc.read_page = brcmnand_read_page;
> chip->ecc.write_page = brcmnand_write_page;
> --
> 2.37.3
>
Thanks,
Miquèl