[PATCH 10/14] qcom: mtd: nand: support for QPIC Page read/write
Abhishek Sahu
absahu at codeaurora.org
Mon Jul 17 00:25:44 PDT 2017
On 2017-07-04 15:14, Archit Taneja wrote:
> On 06/29/2017 12:46 PM, Abhishek Sahu wrote:
>> 1. Add the function for command descriptor preparation which
>> will be used only by BAM DMA and it will form the DMA descriptors
>> containing command elements.
>>
>> 2. Add the data descriptor preparation function which will be used
>> only by BAM DMA for forming the data SGL’s.
>>
>> 3. Add clear BAM transaction and call it before every new request
>>
>> 4. Check DMA mode for ADM or BAM and call the appropriate
>> descriptor formation function.
>>
>> 5. Enable the BAM in NAND_CTRL.
>>
>> Signed-off-by: Abhishek Sahu <absahu at codeaurora.org>
>> ---
>> drivers/mtd/nand/qcom_nandc.c | 190
>> +++++++++++++++++++++++++++++++++++++++---
>> 1 file changed, 180 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/mtd/nand/qcom_nandc.c
>> b/drivers/mtd/nand/qcom_nandc.c
>> index 17766af..4c6e594 100644
>> --- a/drivers/mtd/nand/qcom_nandc.c
>> +++ b/drivers/mtd/nand/qcom_nandc.c
>> @@ -156,6 +156,8 @@
>> #define FETCH_ID 0xb
>> #define RESET_DEVICE 0xd
>>
>> +/* NAND_CTRL bits */
>> +#define BAM_MODE_EN BIT(0)
>> /*
>> * the NAND controller performs reads/writes with ECC in 516 byte
>> chunks.
>> * the driver calls the chunks 'step' or 'codeword' interchangeably
>> @@ -190,6 +192,14 @@
>> */
>> #define NAND_ERASED_CW_SET (0x0008)
>>
>> +/* Returns the dma address for reg read buffer */
>> +#define REG_BUF_DMA_ADDR(chip, vaddr) \
>> + ((chip)->reg_read_buf_phys + \
>> + ((uint8_t *)(vaddr) - (uint8_t *)(chip)->reg_read_buf))
>> +
>> +/* Returns the NAND register physical address */
>> +#define NAND_REG_PHYS(chip, offset) ((chip)->base_phys + (offset))
>> +
>> #define QPIC_PER_CW_MAX_CMD_ELEMENTS (32)
>> #define QPIC_PER_CW_MAX_CMD_SGL (32)
>> #define QPIC_PER_CW_MAX_DATA_SGL (8)
>> @@ -287,7 +297,8 @@ struct nandc_regs {
>> * controller
>> * @dev: parent device
>> * @base: MMIO base
>> - * @base_dma: physical base address of controller registers
>> + * @base_phys: physical base address of controller registers
>> + * @base_dma: dma base address of controller registers
>> * @core_clk: controller clock
>> * @aon_clk: another controller clock
>> *
>> @@ -323,6 +334,7 @@ struct qcom_nand_controller {
>> struct device *dev;
>>
>> void __iomem *base;
>> + phys_addr_t base_phys;
>> dma_addr_t base_dma;
>>
>> struct clk *core_clk;
>> @@ -467,6 +479,29 @@ static void free_bam_transaction(struct
>> qcom_nand_controller *nandc)
>> return bam_txn;
>> }
>>
>> +/* Clears the BAM transaction indexes */
>> +static void clear_bam_transaction(struct qcom_nand_controller *nandc)
>> +{
>> + struct bam_transaction *bam_txn = nandc->bam_txn;
>> +
>> + if (!nandc->dma_bam_enabled)
>> + return;
>> +
>> + bam_txn->bam_ce_pos = 0;
>> + bam_txn->bam_ce_start = 0;
>> + bam_txn->cmd_sgl_pos = 0;
>> + bam_txn->cmd_sgl_start = 0;
>> + bam_txn->tx_sgl_pos = 0;
>> + bam_txn->tx_sgl_start = 0;
>> + bam_txn->rx_sgl_pos = 0;
>> + bam_txn->rx_sgl_start = 0;
>> +
>> + sg_init_table(bam_txn->cmd_sgl, nandc->max_cwperpage *
>> + QPIC_PER_CW_MAX_CMD_SGL);
>> + sg_init_table(bam_txn->data_sg, nandc->max_cwperpage *
>> + QPIC_PER_CW_MAX_DATA_SGL);
>> +}
>> +
>> static inline struct qcom_nand_host *to_qcom_nand_host(struct
>> nand_chip *chip)
>> {
>> return container_of(chip, struct qcom_nand_host, chip);
>> @@ -682,6 +717,102 @@ static int prepare_bam_async_desc(struct
>> qcom_nand_controller *nandc,
>> return 0;
>> }
>>
>> +/*
>> + * Prepares the command descriptor for BAM DMA which will be used for
>> NAND
>> + * register reads and writes. The command descriptor requires the
>> command
>> + * to be formed in command element type so this function uses the
>> command
>> + * element from bam transaction ce array and fills the same with
>> required
>> + * data. A single SGL can contain multiple command elements so
>> + * NAND_BAM_NEXT_SGL will be used for starting the separate SGL
>> + * after the current command element.
>> + */
>> +static int prep_dma_desc_command(struct qcom_nand_controller *nandc,
>> bool read,
>> + int reg_off, const void *vaddr,
>> + int size, unsigned int flags)
>> +{
>> + int bam_ce_size;
>> + int i, ret;
>> + struct bam_cmd_element *bam_ce_buffer;
>> + struct bam_transaction *bam_txn = nandc->bam_txn;
>> +
>> + bam_ce_buffer = &bam_txn->bam_ce[bam_txn->bam_ce_pos];
>> +
>> + /* fill the command desc */
>> + for (i = 0; i < size; i++) {
>> + if (read)
>> + bam_prep_ce(&bam_ce_buffer[i],
>> + NAND_REG_PHYS(nandc, reg_off + 4 * i),
>> + BAM_READ_COMMAND,
>> + REG_BUF_DMA_ADDR(nandc,
>> + (__le32 *)vaddr + i));
>> + else
>> + bam_prep_ce_le32(&bam_ce_buffer[i],
>> + NAND_REG_PHYS(nandc, reg_off + 4 * i),
>> + BAM_WRITE_COMMAND,
>> + *((__le32 *)vaddr + i));
>> + }
>> +
>> + bam_txn->bam_ce_pos += size;
>> +
>> + /* use the separate sgl after this command */
>> + if (flags & NAND_BAM_NEXT_SGL) {
>> + bam_ce_buffer = &bam_txn->bam_ce[bam_txn->bam_ce_start];
>> + bam_ce_size = (bam_txn->bam_ce_pos -
>> + bam_txn->bam_ce_start) *
>> + sizeof(struct bam_cmd_element);
>> + sg_set_buf(&bam_txn->cmd_sgl[bam_txn->cmd_sgl_pos],
>> + bam_ce_buffer, bam_ce_size);
>> + bam_txn->cmd_sgl_pos++;
>> + bam_txn->bam_ce_start = bam_txn->bam_ce_pos;
>> +
>> + if (flags & NAND_BAM_NWD) {
>> + ret = prepare_bam_async_desc(nandc, nandc->cmd_chan,
>> + DMA_PREP_FENCE |
>> + DMA_PREP_CMD);
>> + if (ret)
>> + return ret;
>> + }
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +/*
>> + * Prepares the data descriptor for BAM DMA which will be used for
>> NAND
>> + * data reads and writes.
>> + */
>> +static int prep_dma_desc_data_bam(struct qcom_nand_controller *nandc,
>> bool read,
>> + int reg_off, const void *vaddr,
>> + int size, unsigned int flags)
>> +{
>> + int ret;
>> + struct bam_transaction *bam_txn = nandc->bam_txn;
>> +
>> + if (read) {
>> + sg_set_buf(&bam_txn->data_sg[bam_txn->rx_sgl_pos],
>> + vaddr, size);
>> + bam_txn->rx_sgl_pos++;
>> + } else {
>> + sg_set_buf(&bam_txn->data_sg[bam_txn->tx_sgl_pos],
>> + vaddr, size);
>> + bam_txn->tx_sgl_pos++;
>> +
>> + /*
>> + * BAM will only set EOT for DMA_PREP_INTERRUPT so if this flag
>> + * is not set, form the DMA descriptor
>> + */
>> + if (!(flags & NAND_BAM_NO_EOT)) {
>> + ret = prepare_bam_async_desc(nandc, nandc->tx_chan,
>> + DMA_PREP_INTERRUPT);
>> + if (ret)
>> + return ret;
>> + }
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +/* Prepares the dma descriptor for adm dma engine */
>> static int prep_dma_desc(struct qcom_nand_controller *nandc, bool
>> read,
>> int reg_off, const void *vaddr, int size,
>> bool flow_control)
>> @@ -764,16 +895,19 @@ static int read_reg_dma(struct
>> qcom_nand_controller *nandc, int first,
>> {
>> 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);
>> + if (nandc->dma_bam_enabled)
>> + return prep_dma_desc_command(nandc, true, first, vaddr,
>> + num_regs, flags);
>> +
>> + return prep_dma_desc(nandc, true, first, vaddr, num_regs *
>> sizeof(u32),
>> + flow_control);
>> }
>>
>> /*
>> @@ -789,7 +923,6 @@ static int write_reg_dma(struct
>> qcom_nand_controller *nandc, int first,
>> bool flow_control = false;
>> struct nandc_regs *regs = nandc->regs;
>> void *vaddr;
>> - int size;
>>
>> vaddr = offset_to_nandc_reg(regs, first);
>>
>> @@ -812,9 +945,12 @@ static int write_reg_dma(struct
>> qcom_nand_controller *nandc, int first,
>> if (first == NAND_DEV_CMD_VLD_RESTORE)
>> first = NAND_DEV_CMD_VLD;
>>
>> - size = num_regs * sizeof(u32);
>> + if (nandc->dma_bam_enabled)
>> + return prep_dma_desc_command(nandc, false, first, vaddr,
>> + num_regs, flags);
>>
>> - return prep_dma_desc(nandc, false, first, vaddr, size,
>> flow_control);
>> + return prep_dma_desc(nandc, false, first, vaddr, num_regs *
>> sizeof(u32),
>> + flow_control);
>> }
>>
>> /*
>> @@ -828,6 +964,10 @@ static int write_reg_dma(struct
>> qcom_nand_controller *nandc, int first,
>> static int read_data_dma(struct qcom_nand_controller *nandc, int
>> reg_off,
>> const u8 *vaddr, int size, unsigned int flags)
>> {
>> + if (nandc->dma_bam_enabled)
>> + return prep_dma_desc_data_bam(nandc, true, reg_off, vaddr, size,
>> + flags);
>> +
>> return prep_dma_desc(nandc, true, reg_off, vaddr, size, false);
>> }
>>
>> @@ -842,6 +982,10 @@ static int read_data_dma(struct
>> qcom_nand_controller *nandc, int reg_off,
>> static int write_data_dma(struct qcom_nand_controller *nandc, int
>> reg_off,
>> const u8 *vaddr, int size, unsigned int flags)
>> {
>> + if (nandc->dma_bam_enabled)
>> + return prep_dma_desc_data_bam(nandc, false, reg_off, vaddr,
>> + size, flags);
>> +
>> return prep_dma_desc(nandc, false, reg_off, vaddr, size, false);
>> }
>>
>> @@ -931,6 +1075,8 @@ 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);
>>
>> + clear_bam_transaction(nandc);
>
> For all the commands that go through chip->cmdfunc, can we move
> clear_bam_transaction() calls to pre_command()?
>
Sure. I will move this in pre_command.
> Thanks,
> Archit
>
>> /*
>> * 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
>> @@ -993,6 +1139,8 @@ 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);
>>
>> + clear_bam_transaction(nandc);
>> +
>> nandc_set_reg(nandc, NAND_FLASH_CMD,
>> BLOCK_ERASE | PAGE_ACC | LAST_PAGE);
>> nandc_set_reg(nandc, NAND_ADDR0, page_addr);
>> @@ -1025,10 +1173,13 @@ static int read_id(struct qcom_nand_host
>> *host, int column)
>> if (column == -1)
>> return 0;
>>
>> + clear_bam_transaction(nandc);
>> +
>> 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_FLASH_CHIP_SELECT,
>> + nandc->dma_bam_enabled ? 0 : DM_EN);
>> nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
>>
>> write_reg_dma(nandc, NAND_FLASH_CMD, 4, NAND_BAM_NEXT_SGL);
>> @@ -1045,6 +1196,8 @@ static int reset(struct qcom_nand_host *host)
>> struct nand_chip *chip = &host->chip;
>> struct qcom_nand_controller *nandc =
>> get_qcom_nand_controller(chip);
>>
>> + clear_bam_transaction(nandc);
>> +
>> nandc_set_reg(nandc, NAND_FLASH_CMD, RESET_DEVICE);
>> nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
>>
>> @@ -1561,6 +1714,7 @@ static int qcom_nandc_read_page(struct mtd_info
>> *mtd, struct nand_chip *chip,
>> data_buf = buf;
>> oob_buf = oob_required ? chip->oob_poi : NULL;
>>
>> + clear_bam_transaction(nandc);
>> ret = read_page_ecc(host, data_buf, oob_buf);
>> if (ret) {
>> dev_err(nandc->dev, "failure to read page\n");
>> @@ -1585,6 +1739,8 @@ static int qcom_nandc_read_page_raw(struct
>> mtd_info *mtd,
>> oob_buf = chip->oob_poi;
>>
>> host->use_ecc = false;
>> +
>> + clear_bam_transaction(nandc);
>> update_rw_regs(host, ecc->steps, true);
>>
>> for (i = 0; i < ecc->steps; i++) {
>> @@ -1641,6 +1797,7 @@ static int qcom_nandc_read_oob(struct mtd_info
>> *mtd, struct nand_chip *chip,
>> int ret;
>>
>> clear_read_regs(nandc);
>> + clear_bam_transaction(nandc);
>>
>> host->use_ecc = true;
>> set_address(host, 0, page);
>> @@ -1664,6 +1821,7 @@ static int qcom_nandc_write_page(struct mtd_info
>> *mtd, struct nand_chip *chip,
>> int i, ret;
>>
>> clear_read_regs(nandc);
>> + clear_bam_transaction(nandc);
>>
>> data_buf = (u8 *)buf;
>> oob_buf = chip->oob_poi;
>> @@ -1729,6 +1887,7 @@ static int qcom_nandc_write_page_raw(struct
>> mtd_info *mtd,
>> int i, ret;
>>
>> clear_read_regs(nandc);
>> + clear_bam_transaction(nandc);
>>
>> data_buf = (u8 *)buf;
>> oob_buf = chip->oob_poi;
>> @@ -1803,6 +1962,7 @@ static int qcom_nandc_write_oob(struct mtd_info
>> *mtd, struct nand_chip *chip,
>>
>> host->use_ecc = true;
>>
>> + clear_bam_transaction(nandc);
>> ret = copy_last_cw(host, page);
>> if (ret)
>> return ret;
>> @@ -1860,6 +2020,7 @@ static int qcom_nandc_block_bad(struct mtd_info
>> *mtd, loff_t ofs)
>> */
>> host->use_ecc = false;
>>
>> + clear_bam_transaction(nandc);
>> ret = copy_last_cw(host, page);
>> if (ret)
>> goto err;
>> @@ -1890,6 +2051,7 @@ static int qcom_nandc_block_markbad(struct
>> mtd_info *mtd, loff_t ofs)
>> int page, ret, status = 0;
>>
>> clear_read_regs(nandc);
>> + clear_bam_transaction(nandc);
>>
>> /*
>> * to mark the BBM as bad, we flash the entire last codeword with
>> 0s.
>> @@ -2396,11 +2558,18 @@ static void qcom_nandc_unalloc(struct
>> qcom_nand_controller *nandc)
>> /* one time setup of a few nand controller registers */
>> static int qcom_nandc_setup(struct qcom_nand_controller *nandc)
>> {
>> + u32 nand_ctrl;
>> +
>> /* kill onenand */
>> nandc_write(nandc, SFLASHC_BURST_CFG, 0);
>>
>> - /* enable ADM DMA */
>> - nandc_write(nandc, NAND_FLASH_CHIP_SELECT, DM_EN);
>> + /* enable ADM or BAM DMA */
>> + if (!nandc->dma_bam_enabled) {
>> + nandc_write(nandc, NAND_FLASH_CHIP_SELECT, DM_EN);
>> + } else {
>> + nand_ctrl = nandc_read(nandc, NAND_CTRL);
>> + nandc_write(nandc, NAND_CTRL, nand_ctrl | BAM_MODE_EN);
>> + }
>>
>> /* save the original values of these registers */
>> nandc->cmd1 = nandc_read(nandc, NAND_DEV_CMD1);
>> @@ -2592,6 +2761,7 @@ static int qcom_nandc_probe(struct
>> platform_device *pdev)
>> if (IS_ERR(nandc->base))
>> return PTR_ERR(nandc->base);
>>
>> + nandc->base_phys = res->start;
>> nandc->base_dma = phys_to_dma(dev, (phys_addr_t)res->start);
>>
>> nandc->core_clk = devm_clk_get(dev, "core");
>>
--
Abhishek Sahu
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