Hi Miquel,
Thank you for your review comments...
On 7/9/2020 9:20 pm, Miquel Raynal wrote:
Hi Murugan,
A few more comments below, but I guess the driver looks better now.
+struct ebu_nand_controller {
+ struct nand_controller controller;
+ struct nand_chip chip;
+ struct device *dev;
+ void __iomem *ebu;
+ void __iomem *hsnand;
+ struct dma_chan *dma_tx;
+ struct dma_chan *dma_rx;
+ struct completion dma_access_complete;
+ unsigned long clk_rate;
+ struct clk *clk;
+ u32 nd_para0;
+ u8 cs_num;
+ struct ebu_nand_cs cs[MAX_CS];
+};
+
+static inline struct ebu_nand_controller *nand_to_ebu(struct nand_chip *chip)
+{
+ return container_of(chip, struct ebu_nand_controller, chip);
+}
+
+static u8 ebu_nand_readb(struct nand_chip *chip)
Can't you prefix with intel_ instead of ebu_ ?
+{
+ struct ebu_nand_controller *ebu_host = nand_get_controller_data(chip);
+ void __iomem *nand_wait = ebu_host->ebu + EBU_WAIT;
+ u8 cs_num = ebu_host->cs_num;
+ u32 stat;
+ int ret;
+ u8 val;
+
+ val = readb(ebu_host->cs[cs_num].chipaddr + HSNAND_CS_OFFS);
+
+ ret = readl_poll_timeout(nand_wait, stat, stat & EBU_WAIT_WR_C,
+ 20, 1000);
If you do this operation each time a byte is read/written, you probable
want to shrink the polling delay a little bit, to 1 or even 0.
Ok, Noted.
+ if (ret)
+ dev_warn(ebu_host->dev,
+ "ebu nand write timeout. nand_wait(0x%p)=0x%x\n",
+ nand_wait, readl(nand_wait));
+
+ return val;
You should not return val if ret is !0 I guess
Yes, You're correct.
+}
+
+static void ebu_nand_writeb(struct nand_chip *chip, u32 offset, u8 value)
+{
+ struct ebu_nand_controller *ebu_host = nand_get_controller_data(chip);
+ void __iomem *nand_wait = ebu_host->ebu + EBU_WAIT;
+ u8 cs_num = ebu_host->cs_num;
+ u32 stat;
+ int ret;
+
+ writeb(value, ebu_host->cs[cs_num].chipaddr + offset);
+
+ ret = readl_poll_timeout(nand_wait, stat, stat & EBU_WAIT_WR_C,
+ 20, 1000);
Here as well
Noted.
+ if (ret)
+ dev_warn(ebu_host->dev,
+ "ebu nand write timeout. nand_wait(0x%p)=0x%x\n",
+ nand_wait, readl(nand_wait));
If this can fail, then the helper should return an error and be treated.
Noted, will update.
+}
+
+static void ebu_read_buf(struct nand_chip *chip, u_char *buf, unsigned int len)
+{
+ int i;
+
+ for (i = 0; i < len; i++)
+ buf[i] = ebu_nand_readb(chip);
+}
+
+static void ebu_write_buf(struct nand_chip *chip, const u_char *buf, int len)
+{
+ int i;
+
+ for (i = 0; i < len; i++)
+ ebu_nand_writeb(chip, HSNAND_CS_OFFS, buf[i]);
+}
+
+static void ebu_nand_disable(struct nand_chip *chip)
+{
+ struct ebu_nand_controller *ebu_host = nand_get_controller_data(chip);
+
+ writel(0, ebu_host->ebu + EBU_CON);
+}
+
+static void ebu_select_chip(struct nand_chip *chip)
+{
+ struct ebu_nand_controller *ebu_host = nand_get_controller_data(chip);
+ void __iomem *nand_con = ebu_host->ebu + EBU_CON;
+ u32 cs = ebu_host->cs_num;
+
+ writel(EBU_CON_NANDM_EN | EBU_CON_CSMUX_E_EN | EBU_CON_CS_P_LOW |
+ EBU_CON_SE_P_LOW | EBU_CON_WP_P_LOW | EBU_CON_PRE_P_LOW |
+ EBU_CON_IN_CS_S(cs) | EBU_CON_OUT_CS_S(cs) |
+ EBU_CON_LAT_EN_CS_P, nand_con);
+}
+
+static void ebu_nand_setup_timing(struct ebu_nand_controller *ctrl,
+ const struct nand_sdr_timings *timings)
+{
+ unsigned int rate = clk_get_rate(ctrl->clk) / 1000000;
+ unsigned int period = DIV_ROUND_UP(1000000, rate);
+ u32 trecov, thold, twrwait, trdwait;
+ u32 reg = 0;
+
+ trecov = DIV_ROUND_UP(max(timings->tREA_max, timings->tREH_min),
+ period);
+ reg |= EBU_BUSCON_RECOVC(trecov);
+
+ thold = DIV_ROUND_UP(max(timings->tDH_min, timings->tDS_min), period);
+ reg |= EBU_BUSCON_HOLDC(thold);
+
+ trdwait = DIV_ROUND_UP(max(timings->tRC_min, timings->tREH_min),
+ period);
+ reg |= EBU_BUSCON_WAITRDC(trdwait);
+
+ twrwait = DIV_ROUND_UP(max(timings->tWC_min, timings->tWH_min), period);
+ reg |= EBU_BUSCON_WAITWRC(twrwait);
+
+ reg |= EBU_BUSCON_CMULT_V4 | EBU_BUSCON_BCGEN_CS | EBU_BUSCON_ALEC |
+ EBU_BUSCON_SETUP_EN;
+
+ writel(reg, ctrl->ebu + EBU_BUSCON(ctrl->cs_num));
+}
+
+static int ebu_nand_setup_data_interface(struct nand_chip *chip, int csline,
+ const struct nand_data_interface *conf)
I recently changed the naming around the data interface, please
have a look at the recent commits and update the namings here as
well.
Sure, will go through update accordingly.
+{
+ struct ebu_nand_controller *ctrl = nand_to_ebu(chip);
+ const struct nand_sdr_timings *timings;
+
+ timings = nand_get_sdr_timings(conf);
+ if (IS_ERR(timings))
+ return PTR_ERR(timings);
+
+ if (csline == NAND_DATA_IFACE_CHECK_ONLY)
+ return 0;
+
+ ebu_nand_setup_timing(ctrl, timings);
+
+ return 0;
+}
+
+static int ebu_nand_ooblayout_ecc(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+
+ if (section)
+ return -ERANGE;
+
+ oobregion->offset = HSNAND_ECC_OFFSET;
+ oobregion->length = chip->ecc.total;
+
+ return 0;
+}
+
+static int ebu_nand_ooblayout_free(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+
+ if (section)
+ return -ERANGE;
+
+ oobregion->offset = chip->ecc.total + HSNAND_ECC_OFFSET;
+ oobregion->length = mtd->oobsize - oobregion->offset;
+
+ return 0;
+}
+
+static const struct mtd_ooblayout_ops ebu_nand_ooblayout_ops = {
+ .ecc = ebu_nand_ooblayout_ecc,
+ .free = ebu_nand_ooblayout_free,
+};
+
+static void ebu_dma_rx_callback(void *cookie)
+{
+ struct ebu_nand_controller *ebu_host = cookie;
+
+ dmaengine_terminate_async(ebu_host->dma_rx);
+
+ complete(&ebu_host->dma_access_complete);
+}
+
+static void ebu_dma_tx_callback(void *cookie)
+{
+ struct ebu_nand_controller *ebu_host = cookie;
+
+ dmaengine_terminate_async(ebu_host->dma_tx);
+
+ complete(&ebu_host->dma_access_complete);
+}
+
+static int ebu_dma_start(struct ebu_nand_controller *ebu_host, u32 dir,
+ const u8 *buf, u32 len)
+{
+ struct dma_async_tx_descriptor *tx;
+ struct completion *dma_completion;
+ dma_async_tx_callback callback;
+ struct dma_chan *chan;
+ dma_cookie_t cookie;
+ unsigned long flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
+ dma_addr_t buf_dma;
+ int ret;
+ u32 timeout;
+
+ if (dir == DMA_DEV_TO_MEM) {
+ chan = ebu_host->dma_rx;
+ dma_completion = &ebu_host->dma_access_complete;
+ callback = ebu_dma_rx_callback;
+ } else {
+ chan = ebu_host->dma_tx;
+ dma_completion = &ebu_host->dma_access_complete;
+ callback = ebu_dma_tx_callback;
+ }
+
+ buf_dma = dma_map_single(chan->device->dev, (void *)buf, len, dir);
+ if (dma_mapping_error(chan->device->dev, buf_dma)) {
+ dev_err(ebu_host->dev, "Failed to map DMA buffer\n");
+ ret = -EIO;
+ goto err_unmap;
+ }
+
+ tx = dmaengine_prep_slave_single(chan, buf_dma, len, dir, flags);
+ if (!tx)
+ return -ENXIO;
+
+ tx->callback = callback;
+ tx->callback_param = ebu_host;
+ cookie = tx->tx_submit(tx);
+
+ ret = dma_submit_error(cookie);
+ if (ret) {
+ dev_err(ebu_host->dev, "dma_submit_error %d\n", cookie);
+ ret = -EIO;
+ goto err_unmap;
+ }
+
+ init_completion(dma_completion);
+ dma_async_issue_pending(chan);
+
+ /* Wait DMA to finish the data transfer.*/
+ timeout =
Don't break the line here
Okay, Noted.
+ wait_for_completion_timeout(dma_completion, msecs_to_jiffies(1000));
+ if (!timeout) {
+ dev_err(ebu_host->dev, "I/O Error in DMA RX (status %d)\n",
+ dmaengine_tx_status(chan, cookie, NULL));
+ dmaengine_terminate_sync(chan);
+ ret = -ETIMEDOUT;
+ goto err_unmap;
+ }
+
+ return 0;
+
+err_unmap:
+ dma_unmap_single(ebu_host->dev, buf_dma, len, dir);
+
+ return ret;
+}
+
+static void ebu_nand_trigger(struct ebu_nand_controller *ebu_host,
+ int page, u32 cmd)
+{
+ unsigned int val;
+
+ val = cmd | (page & 0xFF) << HSNAND_CTL1_ADDR_SHIFT;
+ writel(val, ebu_host->hsnand + HSNAND_CTL1);
+ val = (page & 0xFFFF00) >> 8 | HSNAND_CTL2_CYC_N_V5;
+ writel(val, ebu_host->hsnand + HSNAND_CTL2);
+
+ writel(ebu_host->nd_para0, ebu_host->hsnand + HSNAND_PARA0);
+
+ /* clear first, will update later */
+ writel(0xFFFFFFFF, ebu_host->hsnand + HSNAND_CMSG_0);
+ writel(0xFFFFFFFF, ebu_host->hsnand + HSNAND_CMSG_1);
+
+ writel(HSNAND_INT_MSK_CTL_WR_C,
+ ebu_host->hsnand + HSNAND_INT_MSK_CTL);
+
+ val = cmd == NAND_CMD_READ0 ? HSNAND_CTL_RW_READ : HSNAND_CTL_RW_WRITE;
I don't like this, prefer having a "read/write" boolean as a parameter.
Noted, will update.
+
+ writel(HSNAND_CTL_MSG_EN | HSNAND_CTL_CKFF_EN |
+ HSNAND_CTL_ECC_OFF_V8TH | HSNAND_CTL_CE_SEL_CS(ebu_host->cs_num) |
+ HSNAND_CTL_ENABLE_ECC | HSNAND_CTL_GO | val,
+ ebu_host->hsnand + HSNAND_CTL);
+}
+
+static int ebu_nand_read_page_hwecc(struct nand_chip *chip, u8 *buf,
+ int oob_required, int page)
+{
+ struct mtd_info *mtd = nand_to_mtd(chip);
+ struct ebu_nand_controller *ebu_host = nand_get_controller_data(chip);
+ int ret, x;
+
+ ebu_nand_trigger(ebu_host, page, NAND_CMD_READ0);
+
+ ret = ebu_dma_start(ebu_host, DMA_DEV_TO_MEM, buf, mtd->writesize);
+ if (ret)
+ return ret;
+
+ if (oob_required)
+ chip->ecc.read_oob(chip, page);
+
+ x = readl(ebu_host->hsnand + HSNAND_CTL);
+ x &= ~HSNAND_CTL_GO;
+ writel(x, ebu_host->hsnand + HSNAND_CTL);
+
+ return 0;
+}
+
+static int ebu_nand_write_page_hwecc(struct nand_chip *chip, const u8 *buf,
+ int oob_required, int page)
+{
+ struct mtd_info *mtd = nand_to_mtd(chip);
+ struct ebu_nand_controller *ebu_host = nand_get_controller_data(chip);
+ void __iomem *int_sta = ebu_host->hsnand + HSNAND_INT_STA;
+ int ret, val, x;
+ u32 reg;
+
+ ebu_nand_trigger(ebu_host, page, NAND_CMD_SEQIN);
+
+ ret = ebu_dma_start(ebu_host, DMA_MEM_TO_DEV, buf, mtd->writesize);
+ if (ret)
+ return ret;
+
+ if (oob_required) {
+ reg = (chip->oob_poi[3] << 24) | (chip->oob_poi[2] << 16) |
+ (chip->oob_poi[1] << 8) | chip->oob_poi[0];
+
+ writel(reg, ebu_host->hsnand + HSNAND_CMSG_0);
+
+ reg = (chip->oob_poi[7] << 24) | (chip->oob_poi[6] << 16) |
+ (chip->oob_poi[5] << 8) | chip->oob_poi[4];
+
+ writel(reg, ebu_host->hsnand + HSNAND_CMSG_1);
+ }
+
+ ret = readl_poll_timeout_atomic(int_sta, val,
+ !(val & HSNAND_INT_STA_WR_C), 10, 1000);
+ if (ret)
+ return -EIO;
return ret ?
Yes, ret will come.
+
+ x = readl(ebu_host->hsnand + HSNAND_CTL);
+ x &= ~HSNAND_CTL_GO;
+ writel(x, ebu_host->hsnand + HSNAND_CTL);
What is this? Looks like it deserves a helper with a nice name.
Register High Speed NAND control, it is exceeding the 80 characters to
avoid that, short it, will update.
+
+ return 0;
+}
+
+static const u8 ecc_strength[] = { 1, 1, 4, 8, 24, 32, 40, 60, };
^ is this normal?
+
+static int ebu_nand_attach_chip(struct nand_chip *chip)
+{
+ struct mtd_info *mtd = nand_to_mtd(chip);
+ struct ebu_nand_controller *ebu_host = nand_get_controller_data(chip);
+ u32 ecc_steps, ecc_bytes, ecc_total, pagesize, pg_per_blk;
+ u32 ecc_strength_ds = chip->ecc.strength;
+ u32 ecc_size = chip->ecc.size;
+ u32 writesize = mtd->writesize;
+ u32 blocksize = mtd->erasesize;
+ int bch_algo, start, val;
+
+ if (chip->ecc.mode != NAND_ECC_HW)
+ return 0;
+
+ /* Default to an ECC size of 512 */
+ if (!chip->ecc.size)
+ chip->ecc.size = 512;
+
+ switch (ecc_size) {
+ case 512:
+ start = 1;
+ if (!ecc_strength_ds)
+ ecc_strength_ds = 4;
+ break;
+ case 1024:
+ start = 4;
+ if (!ecc_strength_ds)
+ ecc_strength_ds = 32;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ /* BCH ECC algorithm Settings for number of bits per 512B/1024B */
+ bch_algo = round_up(start + 1, 4);
+ for (val = start; val < bch_algo; val++) {
+ if (ecc_strength_ds == ecc_strength[val])
+ break;
+ }
+ if (val == bch_algo)
+ return -EINVAL;
+
+ if (ecc_strength_ds == 8)
+ ecc_bytes = 14;
+ else
+ ecc_bytes = DIV_ROUND_UP(ecc_strength_ds * fls(8 * ecc_size), 8);
+
+ ecc_steps = writesize / ecc_size;
+ ecc_total = ecc_steps * ecc_bytes;
+ if ((ecc_total + 8) > mtd->oobsize)
+ return -ERANGE;
+
+ chip->ecc.total = ecc_total;
+ pagesize = fls(writesize >> 11);
+ if (pagesize > HSNAND_PARA0_PAGE_V8192)
+ return -ERANGE;
+
+ pg_per_blk = fls((blocksize / writesize) >> 6) << 4;
If << 4 is here to mean / 8, then I don't want a shift operation
because it is highly unreadable and compilers know how to optimize
this.
Thanks!, will update.
+ if (pg_per_blk > HSNAND_PARA0_PIB_V256)
+ return -ERANGE;
+
+ ebu_host->nd_para0 = pagesize | pg_per_blk | HSNAND_PARA0_BYP_EN_NP |
+ HSNAND_PARA0_BYP_DEC_NP | HSNAND_PARA0_ADEP_EN |
+ HSNAND_PARA0_TYPE_ONFI | (val << 29);
+
+ mtd_set_ooblayout(mtd, &ebu_nand_ooblayout_ops);
+ chip->ecc.read_page = ebu_nand_read_page_hwecc;
+ chip->ecc.write_page = ebu_nand_write_page_hwecc;
+
+ return 0;
+}
+
+static int ebu_nand_exec_op(struct nand_chip *chip,
+ const struct nand_operation *op, bool check_only)
+{
+ struct ebu_nand_controller *ctrl = nand_to_ebu(chip);
+ const struct nand_op_instr *instr = NULL;
+ unsigned int op_id;
+ int i, time_out, ret = 0;
+ u32 stat;
+
+ if (check_only)
+ ebu_select_chip(chip);
What is the point of selecting the chip if check_only is true?
while converting to exec_op() based data structure, added like other
drivers, let me check and update accordingly, Thanks!.
Regards
Vadivel
+
+ for (op_id = 0; op_id < op->ninstrs; op_id++) {
+ instr = &op->instrs[op_id];
+
+ switch (instr->type) {
+ case NAND_OP_CMD_INSTR:
+ ebu_nand_writeb(chip, HSNAND_CLE_OFFS | HSNAND_CS_OFFS,
+ instr->ctx.cmd.opcode);
+ break;
+
+ case NAND_OP_ADDR_INSTR:
+ for (i = 0; i < instr->ctx.addr.naddrs; i++)
+ ebu_nand_writeb(chip,
+ HSNAND_ALE_OFFS | HSNAND_CS_OFFS,
+ instr->ctx.addr.addrs[i]);
+ break;
+
+ case NAND_OP_DATA_IN_INSTR:
+ ebu_read_buf(chip, instr->ctx.data.buf.in,
+ instr->ctx.data.len);
+ break;
+
+ case NAND_OP_DATA_OUT_INSTR:
+ ebu_write_buf(chip, instr->ctx.data.buf.out,
+ instr->ctx.data.len);
+ break;
+
+ case NAND_OP_WAITRDY_INSTR:
+ time_out = instr->ctx.waitrdy.timeout_ms * 1000;
+ ret = readl_poll_timeout(ctrl->ebu + EBU_WAIT,
+ stat, stat & EBU_WAIT_RDBY,
+ 20, time_out);
+ break;
+ }
+ }
+
+ return ret;
+}
Thanks,
Miquèl
