diff options
Diffstat (limited to 'drivers/mtd/nand/raw/tango_nand.c')
| -rw-r--r-- | drivers/mtd/nand/raw/tango_nand.c | 690 |
1 files changed, 690 insertions, 0 deletions
diff --git a/drivers/mtd/nand/raw/tango_nand.c b/drivers/mtd/nand/raw/tango_nand.c new file mode 100644 index 000000000000..f54518ffb36a --- /dev/null +++ b/drivers/mtd/nand/raw/tango_nand.c @@ -0,0 +1,690 @@ +/* + * Copyright (C) 2016 Sigma Designs + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + */ + +#include <linux/io.h> +#include <linux/of.h> +#include <linux/clk.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/mtd/rawnand.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/platform_device.h> + +/* Offsets relative to chip->base */ +#define PBUS_CMD 0 +#define PBUS_ADDR 4 +#define PBUS_DATA 8 + +/* Offsets relative to reg_base */ +#define NFC_STATUS 0x00 +#define NFC_FLASH_CMD 0x04 +#define NFC_DEVICE_CFG 0x08 +#define NFC_TIMING1 0x0c +#define NFC_TIMING2 0x10 +#define NFC_XFER_CFG 0x14 +#define NFC_PKT_0_CFG 0x18 +#define NFC_PKT_N_CFG 0x1c +#define NFC_BB_CFG 0x20 +#define NFC_ADDR_PAGE 0x24 +#define NFC_ADDR_OFFSET 0x28 +#define NFC_XFER_STATUS 0x2c + +/* NFC_STATUS values */ +#define CMD_READY BIT(31) + +/* NFC_FLASH_CMD values */ +#define NFC_READ 1 +#define NFC_WRITE 2 + +/* NFC_XFER_STATUS values */ +#define PAGE_IS_EMPTY BIT(16) + +/* Offsets relative to mem_base */ +#define METADATA 0x000 +#define ERROR_REPORT 0x1c0 + +/* + * Error reports are split in two bytes: + * byte 0 for the first packet in the page (PKT_0) + * byte 1 for other packets in the page (PKT_N, for N > 0) + * ERR_COUNT_PKT_N is the max error count over all but the first packet. + */ +#define ERR_COUNT_PKT_0(v) (((v) >> 0) & 0x3f) +#define ERR_COUNT_PKT_N(v) (((v) >> 8) & 0x3f) +#define DECODE_FAIL_PKT_0(v) (((v) & BIT(7)) == 0) +#define DECODE_FAIL_PKT_N(v) (((v) & BIT(15)) == 0) + +/* Offsets relative to pbus_base */ +#define PBUS_CS_CTRL 0x83c +#define PBUS_PAD_MODE 0x8f0 + +/* PBUS_CS_CTRL values */ +#define PBUS_IORDY BIT(31) + +/* + * PBUS_PAD_MODE values + * In raw mode, the driver communicates directly with the NAND chips. + * In NFC mode, the NAND Flash controller manages the communication. + * We use NFC mode for read and write; raw mode for everything else. + */ +#define MODE_RAW 0 +#define MODE_NFC BIT(31) + +#define METADATA_SIZE 4 +#define BBM_SIZE 6 +#define FIELD_ORDER 15 + +#define MAX_CS 4 + +struct tango_nfc { + struct nand_hw_control hw; + void __iomem *reg_base; + void __iomem *mem_base; + void __iomem *pbus_base; + struct tango_chip *chips[MAX_CS]; + struct dma_chan *chan; + int freq_kHz; +}; + +#define to_tango_nfc(ptr) container_of(ptr, struct tango_nfc, hw) + +struct tango_chip { + struct nand_chip nand_chip; + void __iomem *base; + u32 timing1; + u32 timing2; + u32 xfer_cfg; + u32 pkt_0_cfg; + u32 pkt_n_cfg; + u32 bb_cfg; +}; + +#define to_tango_chip(ptr) container_of(ptr, struct tango_chip, nand_chip) + +#define XFER_CFG(cs, page_count, steps, metadata_size) \ + ((cs) << 24 | (page_count) << 16 | (steps) << 8 | (metadata_size)) + +#define PKT_CFG(size, strength) ((size) << 16 | (strength)) + +#define BB_CFG(bb_offset, bb_size) ((bb_offset) << 16 | (bb_size)) + +#define TIMING(t0, t1, t2, t3) ((t0) << 24 | (t1) << 16 | (t2) << 8 | (t3)) + +static void tango_cmd_ctrl(struct mtd_info *mtd, int dat, unsigned int ctrl) +{ + struct tango_chip *tchip = to_tango_chip(mtd_to_nand(mtd)); + + if (ctrl & NAND_CLE) + writeb_relaxed(dat, tchip->base + PBUS_CMD); + + if (ctrl & NAND_ALE) + writeb_relaxed(dat, tchip->base + PBUS_ADDR); +} + +static int tango_dev_ready(struct mtd_info *mtd) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct tango_nfc *nfc = to_tango_nfc(chip->controller); + + return readl_relaxed(nfc->pbus_base + PBUS_CS_CTRL) & PBUS_IORDY; +} + +static u8 tango_read_byte(struct mtd_info *mtd) +{ + struct tango_chip *tchip = to_tango_chip(mtd_to_nand(mtd)); + + return readb_relaxed(tchip->base + PBUS_DATA); +} + +static void tango_read_buf(struct mtd_info *mtd, u8 *buf, int len) +{ + struct tango_chip *tchip = to_tango_chip(mtd_to_nand(mtd)); + + ioread8_rep(tchip->base + PBUS_DATA, buf, len); +} + +static void tango_write_buf(struct mtd_info *mtd, const u8 *buf, int len) +{ + struct tango_chip *tchip = to_tango_chip(mtd_to_nand(mtd)); + + iowrite8_rep(tchip->base + PBUS_DATA, buf, len); +} + +static void tango_select_chip(struct mtd_info *mtd, int idx) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct tango_nfc *nfc = to_tango_nfc(chip->controller); + struct tango_chip *tchip = to_tango_chip(chip); + + if (idx < 0) + return; /* No "chip unselect" function */ + + writel_relaxed(tchip->timing1, nfc->reg_base + NFC_TIMING1); + writel_relaxed(tchip->timing2, nfc->reg_base + NFC_TIMING2); + writel_relaxed(tchip->xfer_cfg, nfc->reg_base + NFC_XFER_CFG); + writel_relaxed(tchip->pkt_0_cfg, nfc->reg_base + NFC_PKT_0_CFG); + writel_relaxed(tchip->pkt_n_cfg, nfc->reg_base + NFC_PKT_N_CFG); + writel_relaxed(tchip->bb_cfg, nfc->reg_base + NFC_BB_CFG); +} + +/* + * The controller does not check for bitflips in erased pages, + * therefore software must check instead. + */ +static int check_erased_page(struct nand_chip *chip, u8 *buf) +{ + struct mtd_info *mtd = nand_to_mtd(chip); + u8 *meta = chip->oob_poi + BBM_SIZE; + u8 *ecc = chip->oob_poi + BBM_SIZE + METADATA_SIZE; + const int ecc_size = chip->ecc.bytes; + const int pkt_size = chip->ecc.size; + int i, res, meta_len, bitflips = 0; + + for (i = 0; i < chip->ecc.steps; ++i) { + meta_len = i ? 0 : METADATA_SIZE; + res = nand_check_erased_ecc_chunk(buf, pkt_size, ecc, ecc_size, + meta, meta_len, + chip->ecc.strength); + if (res < 0) + mtd->ecc_stats.failed++; + else + mtd->ecc_stats.corrected += res; + + bitflips = max(res, bitflips); + buf += pkt_size; + ecc += ecc_size; + } + + return bitflips; +} + +static int decode_error_report(struct nand_chip *chip) +{ + u32 status, res; + struct mtd_info *mtd = nand_to_mtd(chip); + struct tango_nfc *nfc = to_tango_nfc(chip->controller); + + status = readl_relaxed(nfc->reg_base + NFC_XFER_STATUS); + if (status & PAGE_IS_EMPTY) + return 0; + + res = readl_relaxed(nfc->mem_base + ERROR_REPORT); + + if (DECODE_FAIL_PKT_0(res) || DECODE_FAIL_PKT_N(res)) + return -EBADMSG; + + /* ERR_COUNT_PKT_N is max, not sum, but that's all we have */ + mtd->ecc_stats.corrected += + ERR_COUNT_PKT_0(res) + ERR_COUNT_PKT_N(res); + + return max(ERR_COUNT_PKT_0(res), ERR_COUNT_PKT_N(res)); +} + +static void tango_dma_callback(void *arg) +{ + complete(arg); +} + +static int do_dma(struct tango_nfc *nfc, enum dma_data_direction dir, int cmd, + const void *buf, int len, int page) +{ + void __iomem *addr = nfc->reg_base + NFC_STATUS; + struct dma_chan *chan = nfc->chan; + struct dma_async_tx_descriptor *desc; + enum dma_transfer_direction tdir; + struct scatterlist sg; + struct completion tx_done; + int err = -EIO; + u32 res, val; + + sg_init_one(&sg, buf, len); + if (dma_map_sg(chan->device->dev, &sg, 1, dir) != 1) + return -EIO; + + tdir = dir == DMA_TO_DEVICE ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM; + desc = dmaengine_prep_slave_sg(chan, &sg, 1, tdir, DMA_PREP_INTERRUPT); + if (!desc) + goto dma_unmap; + + desc->callback = tango_dma_callback; + desc->callback_param = &tx_done; + init_completion(&tx_done); + + writel_relaxed(MODE_NFC, nfc->pbus_base + PBUS_PAD_MODE); + + writel_relaxed(page, nfc->reg_base + NFC_ADDR_PAGE); + writel_relaxed(0, nfc->reg_base + NFC_ADDR_OFFSET); + writel_relaxed(cmd, nfc->reg_base + NFC_FLASH_CMD); + + dmaengine_submit(desc); + dma_async_issue_pending(chan); + + res = wait_for_completion_timeout(&tx_done, HZ); + if (res > 0) + err = readl_poll_timeout(addr, val, val & CMD_READY, 0, 1000); + + writel_relaxed(MODE_RAW, nfc->pbus_base + PBUS_PAD_MODE); + +dma_unmap: + dma_unmap_sg(chan->device->dev, &sg, 1, dir); + + return err; +} + +static int tango_read_page(struct mtd_info *mtd, struct nand_chip *chip, + u8 *buf, int oob_required, int page) +{ + struct tango_nfc *nfc = to_tango_nfc(chip->controller); + int err, res, len = mtd->writesize; + + if (oob_required) + chip->ecc.read_oob(mtd, chip, page); + + err = do_dma(nfc, DMA_FROM_DEVICE, NFC_READ, buf, len, page); + if (err) + return err; + + res = decode_error_report(chip); + if (res < 0) { + chip->ecc.read_oob_raw(mtd, chip, page); + res = check_erased_page(chip, buf); + } + + return res; +} + +static int tango_write_page(struct mtd_info *mtd, struct nand_chip *chip, + const u8 *buf, int oob_required, int page) +{ + struct tango_nfc *nfc = to_tango_nfc(chip->controller); + int err, status, len = mtd->writesize; + + /* Calling tango_write_oob() would send PAGEPROG twice */ + if (oob_required) + return -ENOTSUPP; + + writel_relaxed(0xffffffff, nfc->mem_base + METADATA); + err = do_dma(nfc, DMA_TO_DEVICE, NFC_WRITE, buf, len, page); + if (err) + return err; + + status = chip->waitfunc(mtd, chip); + if (status & NAND_STATUS_FAIL) + return -EIO; + + return 0; +} + +static void aux_read(struct nand_chip *chip, u8 **buf, int len, int *pos) +{ + struct mtd_info *mtd = nand_to_mtd(chip); + + *pos += len; + + if (!*buf) { + /* skip over "len" bytes */ + nand_change_read_column_op(chip, *pos, NULL, 0, false); + } else { + tango_read_buf(mtd, *buf, len); + *buf += len; + } +} + +static void aux_write(struct nand_chip *chip, const u8 **buf, int len, int *pos) +{ + struct mtd_info *mtd = nand_to_mtd(chip); + + *pos += len; + + if (!*buf) { + /* skip over "len" bytes */ + nand_change_write_column_op(chip, *pos, NULL, 0, false); + } else { + tango_write_buf(mtd, *buf, len); + *buf += len; + } +} + +/* + * Physical page layout (not drawn to scale) + * + * NB: Bad Block Marker area splits PKT_N in two (N1, N2). + * + * +---+-----------------+-------+-----+-----------+-----+----+-------+ + * | M | PKT_0 | ECC_0 | ... | N1 | BBM | N2 | ECC_N | + * +---+-----------------+-------+-----+-----------+-----+----+-------+ + * + * Logical page layout: + * + * +-----+---+-------+-----+-------+ + * oob = | BBM | M | ECC_0 | ... | ECC_N | + * +-----+---+-------+-----+-------+ + * + * +-----------------+-----+-----------------+ + * buf = | PKT_0 | ... | PKT_N | + * +-----------------+-----+-----------------+ + */ +static void raw_read(struct nand_chip *chip, u8 *buf, u8 *oob) +{ + struct mtd_info *mtd = nand_to_mtd(chip); + u8 *oob_orig = oob; + const int page_size = mtd->writesize; + const int ecc_size = chip->ecc.bytes; + const int pkt_size = chip->ecc.size; + int pos = 0; /* position within physical page */ + int rem = page_size; /* bytes remaining until BBM area */ + + if (oob) + oob += BBM_SIZE; + + aux_read(chip, &oob, METADATA_SIZE, &pos); + + while (rem > pkt_size) { + aux_read(chip, &buf, pkt_size, &pos); + aux_read(chip, &oob, ecc_size, &pos); + rem = page_size - pos; + } + + aux_read(chip, &buf, rem, &pos); + aux_read(chip, &oob_orig, BBM_SIZE, &pos); + aux_read(chip, &buf, pkt_size - rem, &pos); + aux_read(chip, &oob, ecc_size, &pos); +} + +static void raw_write(struct nand_chip *chip, const u8 *buf, const u8 *oob) +{ + struct mtd_info *mtd = nand_to_mtd(chip); + const u8 *oob_orig = oob; + const int page_size = mtd->writesize; + const int ecc_size = chip->ecc.bytes; + const int pkt_size = chip->ecc.size; + int pos = 0; /* position within physical page */ + int rem = page_size; /* bytes remaining until BBM area */ + + if (oob) + oob += BBM_SIZE; + + aux_write(chip, &oob, METADATA_SIZE, &pos); + + while (rem > pkt_size) { + aux_write(chip, &buf, pkt_size, &pos); + aux_write(chip, &oob, ecc_size, &pos); + rem = page_size - pos; + } + + aux_write(chip, &buf, rem, &pos); + aux_write(chip, &oob_orig, BBM_SIZE, &pos); + aux_write(chip, &buf, pkt_size - rem, &pos); + aux_write(chip, &oob, ecc_size, &pos); +} + +static int tango_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip, + u8 *buf, int oob_required, int page) +{ + nand_read_page_op(chip, page, 0, NULL, 0); + raw_read(chip, buf, chip->oob_poi); + return 0; +} + +static int tango_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip, + const u8 *buf, int oob_required, int page) +{ + nand_prog_page_begin_op(chip, page, 0, NULL, 0); + raw_write(chip, buf, chip->oob_poi); + return nand_prog_page_end_op(chip); +} + +static int tango_read_oob(struct mtd_info *mtd, struct nand_chip *chip, + int page) +{ + nand_read_page_op(chip, page, 0, NULL, 0); + raw_read(chip, NULL, chip->oob_poi); + return 0; +} + +static int tango_write_oob(struct mtd_info *mtd, struct nand_chip *chip, + int page) +{ + nand_prog_page_begin_op(chip, page, 0, NULL, 0); + raw_write(chip, NULL, chip->oob_poi); + return nand_prog_page_end_op(chip); +} + +static int oob_ecc(struct mtd_info *mtd, int idx, struct mtd_oob_region *res) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct nand_ecc_ctrl *ecc = &chip->ecc; + + if (idx >= ecc->steps) + return -ERANGE; + + res->offset = BBM_SIZE + METADATA_SIZE + ecc->bytes * idx; + res->length = ecc->bytes; + + return 0; +} + +static int oob_free(struct mtd_info *mtd, int idx, struct mtd_oob_region *res) +{ + return -ERANGE; /* no free space in spare area */ +} + +static const struct mtd_ooblayout_ops tango_nand_ooblayout_ops = { + .ecc = oob_ecc, + .free = oob_free, +}; + +static u32 to_ticks(int kHz, int ps) +{ + return DIV_ROUND_UP_ULL((u64)kHz * ps, NSEC_PER_SEC); +} + +static int tango_set_timings(struct mtd_info *mtd, int csline, + const struct nand_data_interface *conf) +{ + const struct nand_sdr_timings *sdr = nand_get_sdr_timings(conf); + struct nand_chip *chip = mtd_to_nand(mtd); + struct tango_nfc *nfc = to_tango_nfc(chip->controller); + struct tango_chip *tchip = to_tango_chip(chip); + u32 Trdy, Textw, Twc, Twpw, Tacc, Thold, Trpw, Textr; + int kHz = nfc->freq_kHz; + + if (IS_ERR(sdr)) + return PTR_ERR(sdr); + + if (csline == NAND_DATA_IFACE_CHECK_ONLY) + return 0; + + Trdy = to_ticks(kHz, sdr->tCEA_max - sdr->tREA_max); + Textw = to_ticks(kHz, sdr->tWB_max); + Twc = to_ticks(kHz, sdr->tWC_min); + Twpw = to_ticks(kHz, sdr->tWC_min - sdr->tWP_min); + + Tacc = to_ticks(kHz, sdr->tREA_max); + Thold = to_ticks(kHz, sdr->tREH_min); + Trpw = to_ticks(kHz, sdr->tRC_min - sdr->tREH_min); + Textr = to_ticks(kHz, sdr->tRHZ_max); + + tchip->timing1 = TIMING(Trdy, Textw, Twc, Twpw); + tchip->timing2 = TIMING(Tacc, Thold, Trpw, Textr); + + return 0; +} + +static int chip_init(struct device *dev, struct device_node *np) +{ + u32 cs; + int err, res; + struct mtd_info *mtd; + struct nand_chip *chip; + struct tango_chip *tchip; + struct nand_ecc_ctrl *ecc; + struct tango_nfc *nfc = dev_get_drvdata(dev); + + tchip = devm_kzalloc(dev, sizeof(*tchip), GFP_KERNEL); + if (!tchip) + return -ENOMEM; + + res = of_property_count_u32_elems(np, "reg"); + if (res < 0) + return res; + + if (res != 1) + return -ENOTSUPP; /* Multi-CS chips are not supported */ + + err = of_property_read_u32_index(np, "reg", 0, &cs); + if (err) + return err; + + if (cs >= MAX_CS) + return -EINVAL; + + chip = &tchip->nand_chip; + ecc = &chip->ecc; + mtd = nand_to_mtd(chip); + + chip->read_byte = tango_read_byte; + chip->write_buf = tango_write_buf; + chip->read_buf = tango_read_buf; + chip->select_chip = tango_select_chip; + chip->cmd_ctrl = tango_cmd_ctrl; + chip->dev_ready = tango_dev_ready; + chip->setup_data_interface = tango_set_timings; + chip->options = NAND_USE_BOUNCE_BUFFER | + NAND_NO_SUBPAGE_WRITE | + NAND_WAIT_TCCS; + chip->controller = &nfc->hw; + tchip->base = nfc->pbus_base + (cs * 256); + + nand_set_flash_node(chip, np); + mtd_set_ooblayout(mtd, &tango_nand_ooblayout_ops); + mtd->dev.parent = dev; + + err = nand_scan_ident(mtd, 1, NULL); + if (err) + return err; + + ecc->mode = NAND_ECC_HW; + ecc->algo = NAND_ECC_BCH; + ecc->bytes = DIV_ROUND_UP(ecc->strength * FIELD_ORDER, BITS_PER_BYTE); + + ecc->read_page_raw = tango_read_page_raw; + ecc->write_page_raw = tango_write_page_raw; + ecc->read_page = tango_read_page; + ecc->write_page = tango_write_page; + ecc->read_oob = tango_read_oob; + ecc->write_oob = tango_write_oob; + + err = nand_scan_tail(mtd); + if (err) + return err; + + tchip->xfer_cfg = XFER_CFG(cs, 1, ecc->steps, METADATA_SIZE); + tchip->pkt_0_cfg = PKT_CFG(ecc->size + METADATA_SIZE, ecc->strength); + tchip->pkt_n_cfg = PKT_CFG(ecc->size, ecc->strength); + tchip->bb_cfg = BB_CFG(mtd->writesize, BBM_SIZE); + + err = mtd_device_register(mtd, NULL, 0); + if (err) { + nand_cleanup(chip); + return err; + } + + nfc->chips[cs] = tchip; + + return 0; +} + +static int tango_nand_remove(struct platform_device *pdev) +{ + int cs; + struct tango_nfc *nfc = platform_get_drvdata(pdev); + + dma_release_channel(nfc->chan); + + for (cs = 0; cs < MAX_CS; ++cs) { + if (nfc->chips[cs]) + nand_release(nand_to_mtd(&nfc->chips[cs]->nand_chip)); + } + + return 0; +} + +static int tango_nand_probe(struct platform_device *pdev) +{ + int err; + struct clk *clk; + struct resource *res; + struct tango_nfc *nfc; + struct device_node *np; + + nfc = devm_kzalloc(&pdev->dev, sizeof(*nfc), GFP_KERNEL); + if (!nfc) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + nfc->reg_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(nfc->reg_base)) + return PTR_ERR(nfc->reg_base); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + nfc->mem_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(nfc->mem_base)) + return PTR_ERR(nfc->mem_base); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 2); + nfc->pbus_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(nfc->pbus_base)) + return PTR_ERR(nfc->pbus_base); + + writel_relaxed(MODE_RAW, nfc->pbus_base + PBUS_PAD_MODE); + + clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(clk)) + return PTR_ERR(clk); + + nfc->chan = dma_request_chan(&pdev->dev, "rxtx"); + if (IS_ERR(nfc->chan)) + return PTR_ERR(nfc->chan); + + platform_set_drvdata(pdev, nfc); + nand_hw_control_init(&nfc->hw); + nfc->freq_kHz = clk_get_rate(clk) / 1000; + + for_each_child_of_node(pdev->dev.of_node, np) { + err = chip_init(&pdev->dev, np); + if (err) { + tango_nand_remove(pdev); + return err; + } + } + + return 0; +} + +static const struct of_device_id tango_nand_ids[] = { + { .compatible = "sigma,smp8758-nand" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, tango_nand_ids); + +static struct platform_driver tango_nand_driver = { + .probe = tango_nand_probe, + .remove = tango_nand_remove, + .driver = { + .name = "tango-nand", + .of_match_table = tango_nand_ids, + }, +}; + +module_platform_driver(tango_nand_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Sigma Designs"); +MODULE_DESCRIPTION("Tango4 NAND Flash controller driver"); |