Re: [PATCH] mtd: rawnand: qcom: Implement exec_op()
From: Miquel Raynal
Date: Fri Jun 03 2022 - 12:57:18 EST
Hello,
quic_mdalam@xxxxxxxxxxx wrote on Fri, 3 Jun 2022 21:54:58 +0530:
> Implement exec_op() so we can later get rid of the legacy interface
> implementation.
Thanks for doing this conversion!
>
> Co-developed-by: Sricharan R <quic_srichara@xxxxxxxxxxx>
> Signed-off-by: Sricharan R <quic_srichara@xxxxxxxxxxx>
> Signed-off-by: Md Sadre Alam <quic_mdalam@xxxxxxxxxxx>
> ---
> drivers/mtd/nand/raw/qcom_nandc.c | 368 +++++++++++++++++++++-----------------
> 1 file changed, 204 insertions(+), 164 deletions(-)
>
> diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c
> index 048b255..507921b 100644
> --- a/drivers/mtd/nand/raw/qcom_nandc.c
> +++ b/drivers/mtd/nand/raw/qcom_nandc.c
> @@ -14,6 +14,7 @@
> #include <linux/of.h>
> #include <linux/of_device.h>
> #include <linux/delay.h>
> +#include <linux/iopoll.h>
> #include <linux/dma/qcom_bam_dma.h>
>
> /* NANDc reg offsets */
> @@ -1305,15 +1306,13 @@ static int nandc_param(struct qcom_nand_host *host)
> }
>
> /* sets up descriptors for NAND_CMD_ERASE1 */
> -static int erase_block(struct qcom_nand_host *host, int page_addr)
> +static int erase_block(struct qcom_nand_host *host)
> {
> struct nand_chip *chip = &host->chip;
> struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
>
> nandc_set_reg(chip, NAND_FLASH_CMD,
> OP_BLOCK_ERASE | PAGE_ACC | LAST_PAGE);
> - nandc_set_reg(chip, NAND_ADDR0, page_addr);
> - nandc_set_reg(chip, NAND_ADDR1, 0);
> nandc_set_reg(chip, NAND_DEV0_CFG0,
> host->cfg0_raw & ~(7 << CW_PER_PAGE));
> nandc_set_reg(chip, NAND_DEV0_CFG1, host->cfg1_raw);
> @@ -1321,14 +1320,8 @@ static int erase_block(struct qcom_nand_host *host, int page_addr)
> nandc_set_reg(chip, NAND_FLASH_STATUS, host->clrflashstatus);
> nandc_set_reg(chip, NAND_READ_STATUS, host->clrreadstatus);
>
> - write_reg_dma(nandc, NAND_FLASH_CMD, 3, NAND_BAM_NEXT_SGL);
> + write_reg_dma(nandc, NAND_FLASH_CMD, 1, NAND_BAM_NEXT_SGL);
> write_reg_dma(nandc, NAND_DEV0_CFG0, 2, NAND_BAM_NEXT_SGL);
> - write_reg_dma(nandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
> -
> - read_reg_dma(nandc, NAND_FLASH_STATUS, 1, NAND_BAM_NEXT_SGL);
> -
> - write_reg_dma(nandc, NAND_FLASH_STATUS, 1, 0);
> - write_reg_dma(nandc, NAND_READ_STATUS, 1, NAND_BAM_NEXT_SGL);
>
> return 0;
> }
> @@ -1343,16 +1336,12 @@ static int read_id(struct qcom_nand_host *host, int column)
> return 0;
>
> nandc_set_reg(chip, NAND_FLASH_CMD, OP_FETCH_ID);
> - nandc_set_reg(chip, NAND_ADDR0, column);
> - nandc_set_reg(chip, NAND_ADDR1, 0);
> nandc_set_reg(chip, NAND_FLASH_CHIP_SELECT,
> nandc->props->is_bam ? 0 : DM_EN);
> nandc_set_reg(chip, NAND_EXEC_CMD, 1);
>
> - write_reg_dma(nandc, NAND_FLASH_CMD, 4, NAND_BAM_NEXT_SGL);
> - write_reg_dma(nandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
> -
> - read_reg_dma(nandc, NAND_READ_ID, 1, NAND_BAM_NEXT_SGL);
> + write_reg_dma(nandc, NAND_FLASH_CMD, 1, NAND_BAM_NEXT_SGL);
> + write_reg_dma(nandc, NAND_FLASH_CHIP_SELECT, 1, NAND_BAM_NEXT_SGL);
>
> return 0;
> }
> @@ -1491,7 +1480,6 @@ static void parse_erase_write_errors(struct qcom_nand_host *host, int command)
>
> 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;
>
> @@ -1523,86 +1511,6 @@ static void post_command(struct qcom_nand_host *host, int command)
> }
>
> /*
> - * Implements chip->legacy.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 nand_chip *chip, unsigned int command,
> - int column, int page_addr)
> -{
> - 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, 0);
> - 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.
> *
> @@ -2044,7 +1952,6 @@ static int qcom_nandc_read_page(struct nand_chip *chip, uint8_t *buf,
> 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;
> -
> nand_read_page_op(chip, page, 0, NULL, 0);
> data_buf = buf;
> oob_buf = oob_required ? chip->oob_poi : NULL;
> @@ -2366,64 +2273,6 @@ static int qcom_nandc_block_markbad(struct nand_chip *chip, loff_t ofs)
> }
>
> /*
> - * the three functions below implement chip->legacy.read_byte(),
> - * chip->legacy.read_buf() and chip->legacy.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 nand_chip *chip)
> -{
> - 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 nand_chip *chip, uint8_t *buf, int len)
> -{
> - 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 nand_chip *chip, const uint8_t *buf,
> - int len)
> -{
> - 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 nand_chip *chip, int chipnr)
> -{
> - 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:
> @@ -2738,8 +2587,207 @@ static int qcom_nand_attach_chip(struct nand_chip *chip)
> return 0;
> }
>
> +static int nandc_status(struct nand_chip *chip)
> +{
> + struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
> + struct qcom_nand_host *host = to_qcom_nand_host(chip);
> +
> + memcpy(nandc->data_buffer, &host->status, 1);
> +
> + return 0;
> +}
> +
> +static int qcom_nand_send_command(struct nand_chip *chip, u8 command)
> +{
> + 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 = 0;
> +
> + pre_command(host, command);
> +
> + switch (command) {
> + case NAND_CMD_RESET:
> + ret = reset(host);
> + break;
> + case NAND_CMD_READID:
> + nandc->buf_count = 4;
> + ret = read_id(host, 0);
> + break;
> + case NAND_CMD_PARAM:
> + ret = nandc_param(host);
> + break;
> + case NAND_CMD_ERASE1:
> + ret = erase_block(host);
> + break;
> + case NAND_CMD_STATUS:
> + ret = nandc_status(chip);
> + break;
> + case NAND_CMD_READ0:
> + host->use_ecc = true;
->exec_op() and ECC are orthogonal
> + update_rw_regs(host, ecc->steps, true, 0);
> + break;
> + case NAND_CMD_ERASE2:
> + break;
> + case NAND_CMD_SEQIN:
> + break;
> + case NAND_CMD_PAGEPROG:
> + break;
I am sorry but this is not following ->exec_op() main idea. The
controller is just here to forward requests to the device it must
respect a number of cycles but that's pretty much all. Here you are
actually re-writing ->cmdfunc() which is not what we expect.
> + default:
> + break;
> + }
> +
> + return ret;
> +}
> +
> +static int qcom_nand_send_address(struct nand_chip *chip,
> + const struct nand_op_instr *instr, int cmd)
> +{
> + struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
> + u32 page_addr = 0x0, page_mask = 0x0;
> +
> + page_addr = instr->ctx.addr.addrs[0];
> +
> + /*
> + *Form page address for erase, read, write to using existing api
> + */
> +
> + switch (cmd) {
> + case NAND_CMD_ERASE1:
> + page_addr = instr->ctx.addr.addrs[0];
> + page_mask = instr->ctx.addr.addrs[1];
> + page_mask <<= 8;
> + page_addr = (page_addr | page_mask);
> + page_mask = instr->ctx.addr.addrs[2];
> + page_mask <<= 16;
> + page_addr = (page_addr | page_mask);
> + page_mask = instr->ctx.addr.addrs[3];
> + page_mask <<= 24;
> + page_addr = (page_addr | page_mask);
> + break;
> + case NAND_CMD_READ0:
> + case NAND_CMD_SEQIN:
> + page_addr = instr->ctx.addr.addrs[3];
> + page_addr <<= 24;
> + page_mask = instr->ctx.addr.addrs[2];
> + page_mask <<= 16;
> + page_addr |= page_mask;
> + page_mask = instr->ctx.addr.addrs[1];
> + page_mask <<= 8;
> + page_addr |= page_mask;
> + page_mask = instr->ctx.addr.addrs[0];
> + page_addr |= page_mask;
Same here, just write the number of address cycles that were requested
by the core.
> + break;
> + default:
> + break;
> + }
> +
> + if (cmd == NAND_CMD_PARAM)
> + return 0;
> +
> + nandc_set_reg(chip, NAND_ADDR0, page_addr);
> + nandc_set_reg(chip, NAND_ADDR1, 0);
> +
> + if (cmd != NAND_CMD_SEQIN)
> + write_reg_dma(nandc, NAND_ADDR0, 2, 0);
> +
> + return 0;
> +}
> +
> +static void qcom_nand_read_buf(struct nand_chip *chip, u8 *buf, int len)
> +{
> + struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
> +
> + memcpy(buf, nandc->data_buffer, len);
Is this bounce buffer needed?
> +}
> +
> +static int qcom_nand_exec_instr(struct nand_chip *chip,
> + const struct nand_op_instr *instr)
> +{
> + struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
> + struct qcom_nand_host *host = to_qcom_nand_host(chip);
> + u32 status;
> + int ret = 0;
> + bool wait = false;
> + static int opcode;
> +
> + switch (instr->type) {
> + case NAND_OP_CMD_INSTR:
> + ret = qcom_nand_send_command(chip, instr->ctx.cmd.opcode);
> + if (instr->ctx.cmd.opcode == NAND_CMD_RESET)
> + wait = true;
> + opcode = instr->ctx.cmd.opcode;
> + break;
> + case NAND_OP_ADDR_INSTR:
> + qcom_nand_send_address(chip, instr, opcode);
> + if (opcode != NAND_CMD_READ0 && opcode != NAND_CMD_READSTART &&
> + opcode != NAND_CMD_PARAM && opcode != NAND_CMD_SEQIN)
> + wait = true;
> + break;
> + case NAND_OP_DATA_IN_INSTR:
> + qcom_nand_read_buf(chip, instr->ctx.data.buf.in, instr->ctx.data.len);
> + break;
> + case NAND_OP_DATA_OUT_INSTR:
> + wait = false;
> + break;
> + case NAND_OP_WAITRDY_INSTR:
> + ret = readl_poll_timeout(nandc->base + NAND_FLASH_STATUS, status,
> + (status & FS_READY_BSY_N), 20,
> + instr->ctx.waitrdy.timeout_ms * 1000);
> + if (opcode == NAND_CMD_PARAM)
> + wait = true;
> + default:
> + break;
> + }
> +
> + if (wait) {
> + if (opcode != NAND_CMD_PARAM)
> + write_reg_dma(nandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
> +
> + if (opcode == NAND_CMD_READID)
> + read_reg_dma(nandc, NAND_READ_ID, 1, NAND_BAM_NEXT_SGL);
> +
> + if (opcode == NAND_CMD_ERASE1) {
> + read_reg_dma(nandc, NAND_FLASH_STATUS, 1, NAND_BAM_NEXT_SGL);
> + write_reg_dma(nandc, NAND_FLASH_STATUS, 1, 0);
> + write_reg_dma(nandc, NAND_READ_STATUS, 1, NAND_BAM_NEXT_SGL);
> + }
> +
> + ret = submit_descs(nandc);
> + if (ret)
> + dev_err(nandc->dev, "failure submitting descs for command 0x%02x\n",
> + opcode);
> +
> + free_descs(nandc);
> + post_command(host, opcode);
> + }
> +
> + return ret;
> +}
> +
> +static int qcom_nand_exec_op(struct nand_chip *chip,
> + const struct nand_operation *op,
> + bool check_only)
> +{
> + unsigned int i;
> + int ret = 0;
> +
> + if (check_only)
> + return 0;
> +
> + for (i = 0; i < op->ninstrs; i++) {
> + ret = qcom_nand_exec_instr(chip, &op->instrs[i]);
> + if (ret)
> + break;
> + }
> +
> + return ret;
> +}
> +
> static const struct nand_controller_ops qcom_nandc_ops = {
> .attach_chip = qcom_nand_attach_chip,
> + .exec_op = qcom_nand_exec_op,
> };
>
> static void qcom_nandc_unalloc(struct qcom_nand_controller *nandc)
> @@ -2938,14 +2986,6 @@ static int qcom_nand_host_init_and_register(struct qcom_nand_controller *nandc,
> mtd->owner = THIS_MODULE;
> mtd->dev.parent = dev;
>
> - chip->legacy.cmdfunc = qcom_nandc_command;
> - chip->legacy.select_chip = qcom_nandc_select_chip;
> - chip->legacy.read_byte = qcom_nandc_read_byte;
> - chip->legacy.read_buf = qcom_nandc_read_buf;
> - chip->legacy.write_buf = qcom_nandc_write_buf;
> - chip->legacy.set_features = nand_get_set_features_notsupp;
> - chip->legacy.get_features = nand_get_set_features_notsupp;
> -
> /*
> * 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
Thanks,
Miquèl