nand: raw: add support for MediaTek MT7621 SoC
This patch adds NAND flash controller driver for MediaTek MT7621 SoC.
The NAND flash controller of MT7621 supports only SLC NAND flashes.
It supports 4~12 bits correction with maximum 4KB page size.
diff --git a/drivers/mtd/nand/raw/mt7621_nand.c b/drivers/mtd/nand/raw/mt7621_nand.c
new file mode 100644
index 0000000..2fd8934
--- /dev/null
+++ b/drivers/mtd/nand/raw/mt7621_nand.c
@@ -0,0 +1,1205 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022 MediaTek Inc. All rights reserved.
+ *
+ * Author: Weijie Gao <weijie.gao@mediatek.com>
+ */
+
+#include <log.h>
+#include <nand.h>
+#include <malloc.h>
+#include <asm/addrspace.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/sizes.h>
+#include <linux/bitops.h>
+#include <linux/bitfield.h>
+#include "mt7621_nand.h"
+
+/* NFI core registers */
+#define NFI_CNFG 0x000
+#define CNFG_OP_MODE GENMASK(14, 12)
+#define CNFG_OP_CUSTOM 6
+#define CNFG_AUTO_FMT_EN BIT(9)
+#define CNFG_HW_ECC_EN BIT(8)
+#define CNFG_BYTE_RW BIT(6)
+#define CNFG_READ_MODE BIT(1)
+
+#define NFI_PAGEFMT 0x004
+#define PAGEFMT_FDM_ECC GENMASK(15, 12)
+#define PAGEFMT_FDM GENMASK(11, 8)
+#define PAGEFMT_SPARE GENMASK(5, 4)
+#define PAGEFMT_PAGE GENMASK(1, 0)
+
+#define NFI_CON 0x008
+#define CON_NFI_SEC GENMASK(15, 12)
+#define CON_NFI_BWR BIT(9)
+#define CON_NFI_BRD BIT(8)
+#define CON_NFI_RST BIT(1)
+#define CON_FIFO_FLUSH BIT(0)
+
+#define NFI_ACCCON 0x00c
+#define ACCCON_POECS GENMASK(31, 28)
+#define ACCCON_POECS_DEF 3
+#define ACCCON_PRECS GENMASK(27, 22)
+#define ACCCON_PRECS_DEF 3
+#define ACCCON_C2R GENMASK(21, 16)
+#define ACCCON_C2R_DEF 7
+#define ACCCON_W2R GENMASK(15, 12)
+#define ACCCON_W2R_DEF 7
+#define ACCCON_WH GENMASK(11, 8)
+#define ACCCON_WH_DEF 15
+#define ACCCON_WST GENMASK(7, 4)
+#define ACCCON_WST_DEF 15
+#define ACCCON_WST_MIN 3
+#define ACCCON_RLT GENMASK(3, 0)
+#define ACCCON_RLT_DEF 15
+#define ACCCON_RLT_MIN 3
+
+#define NFI_CMD 0x020
+
+#define NFI_ADDRNOB 0x030
+#define ADDR_ROW_NOB GENMASK(6, 4)
+#define ADDR_COL_NOB GENMASK(2, 0)
+
+#define NFI_COLADDR 0x034
+#define NFI_ROWADDR 0x038
+
+#define NFI_STRDATA 0x040
+#define STR_DATA BIT(0)
+
+#define NFI_CNRNB 0x044
+#define CB2R_TIME GENMASK(7, 4)
+#define STR_CNRNB BIT(0)
+
+#define NFI_DATAW 0x050
+#define NFI_DATAR 0x054
+
+#define NFI_PIO_DIRDY 0x058
+#define PIO_DIRDY BIT(0)
+
+#define NFI_STA 0x060
+#define STA_NFI_FSM GENMASK(19, 16)
+#define STA_FSM_CUSTOM_DATA 14
+#define STA_BUSY BIT(8)
+#define STA_ADDR BIT(1)
+#define STA_CMD BIT(0)
+
+#define NFI_ADDRCNTR 0x070
+#define SEC_CNTR GENMASK(15, 12)
+#define SEC_ADDR GENMASK(9, 0)
+
+#define NFI_CSEL 0x090
+#define CSEL GENMASK(1, 0)
+
+#define NFI_FDM0L 0x0a0
+#define NFI_FDML(n) (0x0a0 + ((n) << 3))
+
+#define NFI_FDM0M 0x0a4
+#define NFI_FDMM(n) (0x0a4 + ((n) << 3))
+
+#define NFI_MASTER_STA 0x210
+#define MAS_ADDR GENMASK(11, 9)
+#define MAS_RD GENMASK(8, 6)
+#define MAS_WR GENMASK(5, 3)
+#define MAS_RDDLY GENMASK(2, 0)
+
+/* ECC engine registers */
+#define ECC_ENCCON 0x000
+#define ENC_EN BIT(0)
+
+#define ECC_ENCCNFG 0x004
+#define ENC_CNFG_MSG GENMASK(28, 16)
+#define ENC_MODE GENMASK(5, 4)
+#define ENC_MODE_NFI 1
+#define ENC_TNUM GENMASK(2, 0)
+
+#define ECC_ENCIDLE 0x00c
+#define ENC_IDLE BIT(0)
+
+#define ECC_DECCON 0x100
+#define DEC_EN BIT(0)
+
+#define ECC_DECCNFG 0x104
+#define DEC_EMPTY_EN BIT(31)
+#define DEC_CS GENMASK(28, 16)
+#define DEC_CON GENMASK(13, 12)
+#define DEC_CON_EL 2
+#define DEC_MODE GENMASK(5, 4)
+#define DEC_MODE_NFI 1
+#define DEC_TNUM GENMASK(2, 0)
+
+#define ECC_DECIDLE 0x10c
+#define DEC_IDLE BIT(1)
+
+#define ECC_DECENUM 0x114
+#define ERRNUM_S 2
+#define ERRNUM_M GENMASK(3, 0)
+
+#define ECC_DECDONE 0x118
+#define DEC_DONE7 BIT(7)
+#define DEC_DONE6 BIT(6)
+#define DEC_DONE5 BIT(5)
+#define DEC_DONE4 BIT(4)
+#define DEC_DONE3 BIT(3)
+#define DEC_DONE2 BIT(2)
+#define DEC_DONE1 BIT(1)
+#define DEC_DONE0 BIT(0)
+
+#define ECC_DECEL(n) (0x11c + (n) * 4)
+#define DEC_EL_ODD_S 16
+#define DEC_EL_M 0x1fff
+#define DEC_EL_BYTE_POS_S 3
+#define DEC_EL_BIT_POS_M GENMASK(2, 0)
+
+#define ECC_FDMADDR 0x13c
+
+/* ENCIDLE and DECIDLE */
+#define ECC_IDLE BIT(0)
+
+#define ACCTIMING(tpoecs, tprecs, tc2r, tw2r, twh, twst, trlt) \
+ (FIELD_PREP(ACCCON_POECS, tpoecs) | \
+ FIELD_PREP(ACCCON_PRECS, tprecs) | \
+ FIELD_PREP(ACCCON_C2R, tc2r) | \
+ FIELD_PREP(ACCCON_W2R, tw2r) | \
+ FIELD_PREP(ACCCON_WH, twh) | \
+ FIELD_PREP(ACCCON_WST, twst) | \
+ FIELD_PREP(ACCCON_RLT, trlt))
+
+#define MASTER_STA_MASK (MAS_ADDR | MAS_RD | MAS_WR | \
+ MAS_RDDLY)
+#define NFI_RESET_TIMEOUT 1000000
+#define NFI_CORE_TIMEOUT 500000
+#define ECC_ENGINE_TIMEOUT 500000
+
+#define ECC_SECTOR_SIZE 512
+#define ECC_PARITY_BITS 13
+
+#define NFI_FDM_SIZE 8
+
+/* Register base */
+#define NFI_BASE 0x1e003000
+#define NFI_ECC_BASE 0x1e003800
+
+static struct mt7621_nfc nfc_dev;
+
+static const u16 mt7621_nfi_page_size[] = { SZ_512, SZ_2K, SZ_4K };
+static const u8 mt7621_nfi_spare_size[] = { 16, 26, 27, 28 };
+static const u8 mt7621_ecc_strength[] = { 4, 6, 8, 10, 12 };
+
+static inline u32 nfi_read32(struct mt7621_nfc *nfc, u32 reg)
+{
+ return readl(nfc->nfi_regs + reg);
+}
+
+static inline void nfi_write32(struct mt7621_nfc *nfc, u32 reg, u32 val)
+{
+ writel(val, nfc->nfi_regs + reg);
+}
+
+static inline u16 nfi_read16(struct mt7621_nfc *nfc, u32 reg)
+{
+ return readw(nfc->nfi_regs + reg);
+}
+
+static inline void nfi_write16(struct mt7621_nfc *nfc, u32 reg, u16 val)
+{
+ writew(val, nfc->nfi_regs + reg);
+}
+
+static inline void ecc_write16(struct mt7621_nfc *nfc, u32 reg, u16 val)
+{
+ writew(val, nfc->ecc_regs + reg);
+}
+
+static inline u32 ecc_read32(struct mt7621_nfc *nfc, u32 reg)
+{
+ return readl(nfc->ecc_regs + reg);
+}
+
+static inline void ecc_write32(struct mt7621_nfc *nfc, u32 reg, u32 val)
+{
+ return writel(val, nfc->ecc_regs + reg);
+}
+
+static inline u8 *oob_fdm_ptr(struct nand_chip *nand, int sect)
+{
+ return nand->oob_poi + sect * NFI_FDM_SIZE;
+}
+
+static inline u8 *oob_ecc_ptr(struct mt7621_nfc *nfc, int sect)
+{
+ struct nand_chip *nand = &nfc->nand;
+
+ return nand->oob_poi + nand->ecc.steps * NFI_FDM_SIZE +
+ sect * (nfc->spare_per_sector - NFI_FDM_SIZE);
+}
+
+static inline u8 *page_data_ptr(struct nand_chip *nand, const u8 *buf,
+ int sect)
+{
+ return (u8 *)buf + sect * nand->ecc.size;
+}
+
+static int mt7621_ecc_wait_idle(struct mt7621_nfc *nfc, u32 reg)
+{
+ u32 val;
+ int ret;
+
+ ret = readw_poll_timeout(nfc->ecc_regs + reg, val, val & ECC_IDLE,
+ ECC_ENGINE_TIMEOUT);
+ if (ret) {
+ pr_warn("ECC engine timed out entering idle mode\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int mt7621_ecc_decoder_wait_done(struct mt7621_nfc *nfc, u32 sect)
+{
+ u32 val;
+ int ret;
+
+ ret = readw_poll_timeout(nfc->ecc_regs + ECC_DECDONE, val,
+ val & (1 << sect), ECC_ENGINE_TIMEOUT);
+ if (ret) {
+ pr_warn("ECC decoder for sector %d timed out\n", sect);
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+static void mt7621_ecc_encoder_op(struct mt7621_nfc *nfc, bool enable)
+{
+ mt7621_ecc_wait_idle(nfc, ECC_ENCIDLE);
+ ecc_write16(nfc, ECC_ENCCON, enable ? ENC_EN : 0);
+}
+
+static void mt7621_ecc_decoder_op(struct mt7621_nfc *nfc, bool enable)
+{
+ mt7621_ecc_wait_idle(nfc, ECC_DECIDLE);
+ ecc_write16(nfc, ECC_DECCON, enable ? DEC_EN : 0);
+}
+
+static int mt7621_ecc_correct_check(struct mt7621_nfc *nfc, u8 *sector_buf,
+ u8 *fdm_buf, u32 sect)
+{
+ struct nand_chip *nand = &nfc->nand;
+ u32 decnum, num_error_bits, fdm_end_bits;
+ u32 error_locations, error_bit_loc;
+ u32 error_byte_pos, error_bit_pos;
+ int bitflips = 0;
+ u32 i;
+
+ decnum = ecc_read32(nfc, ECC_DECENUM);
+ num_error_bits = (decnum >> (sect << ERRNUM_S)) & ERRNUM_M;
+ fdm_end_bits = (nand->ecc.size + NFI_FDM_SIZE) << 3;
+
+ if (!num_error_bits)
+ return 0;
+
+ if (num_error_bits == ERRNUM_M)
+ return -1;
+
+ for (i = 0; i < num_error_bits; i++) {
+ error_locations = ecc_read32(nfc, ECC_DECEL(i / 2));
+ error_bit_loc = (error_locations >> ((i % 2) * DEC_EL_ODD_S)) &
+ DEC_EL_M;
+ error_byte_pos = error_bit_loc >> DEC_EL_BYTE_POS_S;
+ error_bit_pos = error_bit_loc & DEC_EL_BIT_POS_M;
+
+ if (error_bit_loc < (nand->ecc.size << 3)) {
+ if (sector_buf) {
+ sector_buf[error_byte_pos] ^=
+ (1 << error_bit_pos);
+ }
+ } else if (error_bit_loc < fdm_end_bits) {
+ if (fdm_buf) {
+ fdm_buf[error_byte_pos - nand->ecc.size] ^=
+ (1 << error_bit_pos);
+ }
+ }
+
+ bitflips++;
+ }
+
+ return bitflips;
+}
+
+static int mt7621_nfc_wait_write_completion(struct mt7621_nfc *nfc,
+ struct nand_chip *nand)
+{
+ u16 val;
+ int ret;
+
+ ret = readw_poll_timeout(nfc->nfi_regs + NFI_ADDRCNTR, val,
+ FIELD_GET(SEC_CNTR, val) >= nand->ecc.steps,
+ NFI_CORE_TIMEOUT);
+
+ if (ret) {
+ pr_warn("NFI core write operation timed out\n");
+ return -ETIMEDOUT;
+ }
+
+ return ret;
+}
+
+static void mt7621_nfc_hw_reset(struct mt7621_nfc *nfc)
+{
+ u32 val;
+ int ret;
+
+ /* reset all registers and force the NFI master to terminate */
+ nfi_write16(nfc, NFI_CON, CON_FIFO_FLUSH | CON_NFI_RST);
+
+ /* wait for the master to finish the last transaction */
+ ret = readw_poll_timeout(nfc->nfi_regs + NFI_MASTER_STA, val,
+ !(val & MASTER_STA_MASK), NFI_RESET_TIMEOUT);
+ if (ret) {
+ pr_warn("Failed to reset NFI master in %dms\n",
+ NFI_RESET_TIMEOUT);
+ }
+
+ /* ensure any status register affected by the NFI master is reset */
+ nfi_write16(nfc, NFI_CON, CON_FIFO_FLUSH | CON_NFI_RST);
+ nfi_write16(nfc, NFI_STRDATA, 0);
+}
+
+static inline void mt7621_nfc_hw_init(struct mt7621_nfc *nfc)
+{
+ u32 acccon;
+
+ /*
+ * CNRNB: nand ready/busy register
+ * -------------------------------
+ * 7:4: timeout register for polling the NAND busy/ready signal
+ * 0 : poll the status of the busy/ready signal after [7:4]*16 cycles.
+ */
+ nfi_write16(nfc, NFI_CNRNB, CB2R_TIME | STR_CNRNB);
+
+ mt7621_nfc_hw_reset(nfc);
+
+ /* Apply default access timing */
+ acccon = ACCTIMING(ACCCON_POECS_DEF, ACCCON_PRECS_DEF, ACCCON_C2R_DEF,
+ ACCCON_W2R_DEF, ACCCON_WH_DEF, ACCCON_WST_DEF,
+ ACCCON_RLT_DEF);
+
+ nfi_write32(nfc, NFI_ACCCON, acccon);
+}
+
+static int mt7621_nfc_send_command(struct mt7621_nfc *nfc, u8 command)
+{
+ u32 val;
+ int ret;
+
+ nfi_write32(nfc, NFI_CMD, command);
+
+ ret = readl_poll_timeout(nfc->nfi_regs + NFI_STA, val, !(val & STA_CMD),
+ NFI_CORE_TIMEOUT);
+ if (ret) {
+ pr_warn("NFI core timed out entering command mode\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int mt7621_nfc_send_address_byte(struct mt7621_nfc *nfc, int addr)
+{
+ u32 val;
+ int ret;
+
+ nfi_write32(nfc, NFI_COLADDR, addr);
+ nfi_write32(nfc, NFI_ROWADDR, 0);
+ nfi_write16(nfc, NFI_ADDRNOB, 1);
+
+ ret = readl_poll_timeout(nfc->nfi_regs + NFI_STA, val,
+ !(val & STA_ADDR), NFI_CORE_TIMEOUT);
+ if (ret) {
+ pr_warn("NFI core timed out entering address mode\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static void mt7621_nfc_cmd_ctrl(struct mtd_info *mtd, int dat,
+ unsigned int ctrl)
+{
+ struct mt7621_nfc *nfc = nand_get_controller_data(mtd_to_nand(mtd));
+
+ if (ctrl & NAND_ALE) {
+ mt7621_nfc_send_address_byte(nfc, dat & 0xff);
+ } else if (ctrl & NAND_CLE) {
+ mt7621_nfc_hw_reset(nfc);
+ nfi_write16(nfc, NFI_CNFG,
+ FIELD_PREP(CNFG_OP_MODE, CNFG_OP_CUSTOM));
+ mt7621_nfc_send_command(nfc, dat);
+ }
+}
+
+static int mt7621_nfc_dev_ready(struct mtd_info *mtd)
+{
+ struct mt7621_nfc *nfc = nand_get_controller_data(mtd_to_nand(mtd));
+
+ if (nfi_read32(nfc, NFI_STA) & STA_BUSY)
+ return 0;
+
+ return 1;
+}
+
+static void mt7621_nfc_select_chip(struct mtd_info *mtd, int chipnr)
+{
+ struct mt7621_nfc *nfc = nand_get_controller_data(mtd_to_nand(mtd));
+
+ nfi_write16(nfc, NFI_CSEL, 0);
+}
+
+static void mt7621_nfc_wait_pio_ready(struct mt7621_nfc *nfc)
+{
+ int ret;
+ u16 val;
+
+ ret = readw_poll_timeout(nfc->nfi_regs + NFI_PIO_DIRDY, val,
+ val & PIO_DIRDY, NFI_CORE_TIMEOUT);
+ if (ret < 0)
+ pr_err("NFI core PIO mode not ready\n");
+}
+
+static u32 mt7621_nfc_pio_read(struct mt7621_nfc *nfc, bool br)
+{
+ u32 reg, fsm;
+
+ /* after each byte read, the NFI_STA reg is reset by the hardware */
+ reg = nfi_read32(nfc, NFI_STA);
+ fsm = FIELD_GET(STA_NFI_FSM, reg);
+
+ if (fsm != STA_FSM_CUSTOM_DATA) {
+ reg = nfi_read16(nfc, NFI_CNFG);
+ reg |= CNFG_READ_MODE | CNFG_BYTE_RW;
+ if (!br)
+ reg &= ~CNFG_BYTE_RW;
+ nfi_write16(nfc, NFI_CNFG, reg);
+
+ /*
+ * set to max sector to allow the HW to continue reading over
+ * unaligned accesses
+ */
+ nfi_write16(nfc, NFI_CON, CON_NFI_SEC | CON_NFI_BRD);
+
+ /* trigger to fetch data */
+ nfi_write16(nfc, NFI_STRDATA, STR_DATA);
+ }
+
+ mt7621_nfc_wait_pio_ready(nfc);
+
+ return nfi_read32(nfc, NFI_DATAR);
+}
+
+static void mt7621_nfc_read_data(struct mt7621_nfc *nfc, u8 *buf, u32 len)
+{
+ while (((uintptr_t)buf & 3) && len) {
+ *buf = mt7621_nfc_pio_read(nfc, true);
+ buf++;
+ len--;
+ }
+
+ while (len >= 4) {
+ *(u32 *)buf = mt7621_nfc_pio_read(nfc, false);
+ buf += 4;
+ len -= 4;
+ }
+
+ while (len) {
+ *buf = mt7621_nfc_pio_read(nfc, true);
+ buf++;
+ len--;
+ }
+}
+
+static void mt7621_nfc_read_data_discard(struct mt7621_nfc *nfc, u32 len)
+{
+ while (len >= 4) {
+ mt7621_nfc_pio_read(nfc, false);
+ len -= 4;
+ }
+
+ while (len) {
+ mt7621_nfc_pio_read(nfc, true);
+ len--;
+ }
+}
+
+static void mt7621_nfc_pio_write(struct mt7621_nfc *nfc, u32 val, bool bw)
+{
+ u32 reg, fsm;
+
+ reg = nfi_read32(nfc, NFI_STA);
+ fsm = FIELD_GET(STA_NFI_FSM, reg);
+
+ if (fsm != STA_FSM_CUSTOM_DATA) {
+ reg = nfi_read16(nfc, NFI_CNFG);
+ reg &= ~(CNFG_READ_MODE | CNFG_BYTE_RW);
+ if (bw)
+ reg |= CNFG_BYTE_RW;
+ nfi_write16(nfc, NFI_CNFG, reg);
+
+ nfi_write16(nfc, NFI_CON, CON_NFI_SEC | CON_NFI_BWR);
+ nfi_write16(nfc, NFI_STRDATA, STR_DATA);
+ }
+
+ mt7621_nfc_wait_pio_ready(nfc);
+ nfi_write32(nfc, NFI_DATAW, val);
+}
+
+static void mt7621_nfc_write_data(struct mt7621_nfc *nfc, const u8 *buf,
+ u32 len)
+{
+ while (((uintptr_t)buf & 3) && len) {
+ mt7621_nfc_pio_write(nfc, *buf, true);
+ buf++;
+ len--;
+ }
+
+ while (len >= 4) {
+ mt7621_nfc_pio_write(nfc, *(const u32 *)buf, false);
+ buf += 4;
+ len -= 4;
+ }
+
+ while (len) {
+ mt7621_nfc_pio_write(nfc, *buf, true);
+ buf++;
+ len--;
+ }
+}
+
+static void mt7621_nfc_write_data_empty(struct mt7621_nfc *nfc, u32 len)
+{
+ while (len >= 4) {
+ mt7621_nfc_pio_write(nfc, 0xffffffff, false);
+ len -= 4;
+ }
+
+ while (len) {
+ mt7621_nfc_pio_write(nfc, 0xff, true);
+ len--;
+ }
+}
+
+static void mt7621_nfc_write_byte(struct mtd_info *mtd, u8 byte)
+{
+ struct mt7621_nfc *nfc = nand_get_controller_data(mtd_to_nand(mtd));
+
+ mt7621_nfc_pio_write(nfc, byte, true);
+}
+
+static void mt7621_nfc_write_buf(struct mtd_info *mtd, const u8 *buf, int len)
+{
+ struct mt7621_nfc *nfc = nand_get_controller_data(mtd_to_nand(mtd));
+
+ return mt7621_nfc_write_data(nfc, buf, len);
+}
+
+static u8 mt7621_nfc_read_byte(struct mtd_info *mtd)
+{
+ struct mt7621_nfc *nfc = nand_get_controller_data(mtd_to_nand(mtd));
+
+ return mt7621_nfc_pio_read(nfc, true);
+}
+
+static void mt7621_nfc_read_buf(struct mtd_info *mtd, u8 *buf, int len)
+{
+ struct mt7621_nfc *nfc = nand_get_controller_data(mtd_to_nand(mtd));
+
+ mt7621_nfc_read_data(nfc, buf, len);
+}
+
+static int mt7621_nfc_calc_ecc_strength(struct mt7621_nfc *nfc,
+ u32 avail_ecc_bytes)
+{
+ struct nand_chip *nand = &nfc->nand;
+ struct mtd_info *mtd = nand_to_mtd(nand);
+ u32 strength;
+ int i;
+
+ strength = avail_ecc_bytes * 8 / ECC_PARITY_BITS;
+
+ /* Find the closest supported ecc strength */
+ for (i = ARRAY_SIZE(mt7621_ecc_strength) - 1; i >= 0; i--) {
+ if (mt7621_ecc_strength[i] <= strength)
+ break;
+ }
+
+ if (unlikely(i < 0)) {
+ pr_err("OOB size (%u) is not supported\n", mtd->oobsize);
+ return -EINVAL;
+ }
+
+ nand->ecc.strength = mt7621_ecc_strength[i];
+ nand->ecc.bytes = DIV_ROUND_UP(nand->ecc.strength * ECC_PARITY_BITS, 8);
+
+ pr_debug("ECC strength adjusted to %u bits\n", nand->ecc.strength);
+
+ return i;
+}
+
+static int mt7621_nfc_set_spare_per_sector(struct mt7621_nfc *nfc)
+{
+ struct nand_chip *nand = &nfc->nand;
+ struct mtd_info *mtd = nand_to_mtd(nand);
+ u32 size;
+ int i;
+
+ size = nand->ecc.bytes + NFI_FDM_SIZE;
+
+ /* Find the closest supported spare size */
+ for (i = 0; i < ARRAY_SIZE(mt7621_nfi_spare_size); i++) {
+ if (mt7621_nfi_spare_size[i] >= size)
+ break;
+ }
+
+ if (unlikely(i >= ARRAY_SIZE(mt7621_nfi_spare_size))) {
+ pr_err("OOB size (%u) is not supported\n", mtd->oobsize);
+ return -EINVAL;
+ }
+
+ nfc->spare_per_sector = mt7621_nfi_spare_size[i];
+
+ return i;
+}
+
+static int mt7621_nfc_ecc_init(struct mt7621_nfc *nfc)
+{
+ struct nand_chip *nand = &nfc->nand;
+ struct mtd_info *mtd = nand_to_mtd(nand);
+ u32 avail_ecc_bytes, encode_block_size, decode_block_size;
+ u32 ecc_enccfg, ecc_deccfg;
+ int ecc_cap;
+
+ nand->ecc.options |= NAND_ECC_CUSTOM_PAGE_ACCESS;
+
+ nand->ecc.size = ECC_SECTOR_SIZE;
+ nand->ecc.steps = mtd->writesize / nand->ecc.size;
+
+ avail_ecc_bytes = mtd->oobsize / nand->ecc.steps - NFI_FDM_SIZE;
+
+ ecc_cap = mt7621_nfc_calc_ecc_strength(nfc, avail_ecc_bytes);
+ if (ecc_cap < 0)
+ return ecc_cap;
+
+ /* Sector + FDM */
+ encode_block_size = (nand->ecc.size + NFI_FDM_SIZE) * 8;
+ ecc_enccfg = ecc_cap | FIELD_PREP(ENC_MODE, ENC_MODE_NFI) |
+ FIELD_PREP(ENC_CNFG_MSG, encode_block_size);
+
+ /* Sector + FDM + ECC parity bits */
+ decode_block_size = ((nand->ecc.size + NFI_FDM_SIZE) * 8) +
+ nand->ecc.strength * ECC_PARITY_BITS;
+ ecc_deccfg = ecc_cap | FIELD_PREP(DEC_MODE, DEC_MODE_NFI) |
+ FIELD_PREP(DEC_CS, decode_block_size) |
+ FIELD_PREP(DEC_CON, DEC_CON_EL) | DEC_EMPTY_EN;
+
+ mt7621_ecc_encoder_op(nfc, false);
+ ecc_write32(nfc, ECC_ENCCNFG, ecc_enccfg);
+
+ mt7621_ecc_decoder_op(nfc, false);
+ ecc_write32(nfc, ECC_DECCNFG, ecc_deccfg);
+
+ return 0;
+}
+
+static int mt7621_nfc_set_page_format(struct mt7621_nfc *nfc)
+{
+ struct nand_chip *nand = &nfc->nand;
+ struct mtd_info *mtd = nand_to_mtd(nand);
+ int i, spare_size;
+ u32 pagefmt;
+
+ spare_size = mt7621_nfc_set_spare_per_sector(nfc);
+ if (spare_size < 0)
+ return spare_size;
+
+ for (i = 0; i < ARRAY_SIZE(mt7621_nfi_page_size); i++) {
+ if (mt7621_nfi_page_size[i] == mtd->writesize)
+ break;
+ }
+
+ if (unlikely(i >= ARRAY_SIZE(mt7621_nfi_page_size))) {
+ pr_err("Page size (%u) is not supported\n", mtd->writesize);
+ return -EINVAL;
+ }
+
+ pagefmt = FIELD_PREP(PAGEFMT_PAGE, i) |
+ FIELD_PREP(PAGEFMT_SPARE, spare_size) |
+ FIELD_PREP(PAGEFMT_FDM, NFI_FDM_SIZE) |
+ FIELD_PREP(PAGEFMT_FDM_ECC, NFI_FDM_SIZE);
+
+ nfi_write16(nfc, NFI_PAGEFMT, pagefmt);
+
+ return 0;
+}
+
+static int mt7621_nfc_attach_chip(struct nand_chip *nand)
+{
+ struct mt7621_nfc *nfc = nand_get_controller_data(nand);
+ int ret;
+
+ if (nand->options & NAND_BUSWIDTH_16) {
+ pr_err("16-bit buswidth is not supported");
+ return -EINVAL;
+ }
+
+ ret = mt7621_nfc_ecc_init(nfc);
+ if (ret)
+ return ret;
+
+ return mt7621_nfc_set_page_format(nfc);
+}
+
+static void mt7621_nfc_write_fdm(struct mt7621_nfc *nfc)
+{
+ struct nand_chip *nand = &nfc->nand;
+ u32 vall, valm;
+ u8 *oobptr;
+ int i, j;
+
+ for (i = 0; i < nand->ecc.steps; i++) {
+ vall = 0;
+ valm = 0;
+ oobptr = oob_fdm_ptr(nand, i);
+
+ for (j = 0; j < 4; j++)
+ vall |= (u32)oobptr[j] << (j * 8);
+
+ for (j = 0; j < 4; j++)
+ valm |= (u32)oobptr[j + 4] << (j * 8);
+
+ nfi_write32(nfc, NFI_FDML(i), vall);
+ nfi_write32(nfc, NFI_FDMM(i), valm);
+ }
+}
+
+static void mt7621_nfc_read_sector_fdm(struct mt7621_nfc *nfc, u32 sect)
+{
+ struct nand_chip *nand = &nfc->nand;
+ u32 vall, valm;
+ u8 *oobptr;
+ int i;
+
+ vall = nfi_read32(nfc, NFI_FDML(sect));
+ valm = nfi_read32(nfc, NFI_FDMM(sect));
+ oobptr = oob_fdm_ptr(nand, sect);
+
+ for (i = 0; i < 4; i++)
+ oobptr[i] = (vall >> (i * 8)) & 0xff;
+
+ for (i = 0; i < 4; i++)
+ oobptr[i + 4] = (valm >> (i * 8)) & 0xff;
+}
+
+static int mt7621_nfc_read_page_hwecc(struct mtd_info *mtd,
+ struct nand_chip *nand, uint8_t *buf,
+ int oob_required, int page)
+{
+ struct mt7621_nfc *nfc = nand_get_controller_data(nand);
+ int bitflips = 0, ret = 0;
+ int rc, i;
+
+ nand_read_page_op(nand, page, 0, NULL, 0);
+
+ nfi_write16(nfc, NFI_CNFG, FIELD_PREP(CNFG_OP_MODE, CNFG_OP_CUSTOM) |
+ CNFG_READ_MODE | CNFG_AUTO_FMT_EN | CNFG_HW_ECC_EN);
+
+ mt7621_ecc_decoder_op(nfc, true);
+
+ nfi_write16(nfc, NFI_CON, FIELD_PREP(CON_NFI_SEC, nand->ecc.steps) |
+ CON_NFI_BRD);
+
+ for (i = 0; i < nand->ecc.steps; i++) {
+ if (buf)
+ mt7621_nfc_read_data(nfc, page_data_ptr(nand, buf, i),
+ nand->ecc.size);
+ else
+ mt7621_nfc_read_data_discard(nfc, nand->ecc.size);
+
+ rc = mt7621_ecc_decoder_wait_done(nfc, i);
+
+ mt7621_nfc_read_sector_fdm(nfc, i);
+
+ if (rc < 0) {
+ ret = -EIO;
+ continue;
+ }
+
+ rc = mt7621_ecc_correct_check(nfc,
+ buf ? page_data_ptr(nand, buf, i) : NULL,
+ oob_fdm_ptr(nand, i), i);
+
+ if (rc < 0) {
+ pr_warn("Uncorrectable ECC error at page %d step %d\n",
+ page, i);
+ bitflips = nand->ecc.strength + 1;
+ mtd->ecc_stats.failed++;
+ } else {
+ if (rc > bitflips)
+ bitflips = rc;
+ mtd->ecc_stats.corrected += rc;
+ }
+ }
+
+ mt7621_ecc_decoder_op(nfc, false);
+
+ nfi_write16(nfc, NFI_CON, 0);
+
+ if (ret < 0)
+ return ret;
+
+ return bitflips;
+}
+
+static int mt7621_nfc_read_page_raw(struct mtd_info *mtd,
+ struct nand_chip *nand, uint8_t *buf,
+ int oob_required, int page)
+{
+ struct mt7621_nfc *nfc = nand_get_controller_data(nand);
+ int i;
+
+ nand_read_page_op(nand, page, 0, NULL, 0);
+
+ nfi_write16(nfc, NFI_CNFG, FIELD_PREP(CNFG_OP_MODE, CNFG_OP_CUSTOM) |
+ CNFG_READ_MODE);
+
+ nfi_write16(nfc, NFI_CON, FIELD_PREP(CON_NFI_SEC, nand->ecc.steps) |
+ CON_NFI_BRD);
+
+ for (i = 0; i < nand->ecc.steps; i++) {
+ /* Read data */
+ if (buf)
+ mt7621_nfc_read_data(nfc, page_data_ptr(nand, buf, i),
+ nand->ecc.size);
+ else
+ mt7621_nfc_read_data_discard(nfc, nand->ecc.size);
+
+ /* Read FDM */
+ mt7621_nfc_read_data(nfc, oob_fdm_ptr(nand, i), NFI_FDM_SIZE);
+
+ /* Read ECC parity data */
+ mt7621_nfc_read_data(nfc, oob_ecc_ptr(nfc, i),
+ nfc->spare_per_sector - NFI_FDM_SIZE);
+ }
+
+ nfi_write16(nfc, NFI_CON, 0);
+
+ return 0;
+}
+
+static int mt7621_nfc_read_oob_hwecc(struct mtd_info *mtd,
+ struct nand_chip *nand, int page)
+{
+ return mt7621_nfc_read_page_hwecc(mtd, nand, NULL, 1, page);
+}
+
+static int mt7621_nfc_read_oob_raw(struct mtd_info *mtd,
+ struct nand_chip *nand, int page)
+{
+ return mt7621_nfc_read_page_raw(mtd, nand, NULL, 1, page);
+}
+
+static int mt7621_nfc_check_empty_page(struct nand_chip *nand, const u8 *buf)
+{
+ struct mtd_info *mtd = nand_to_mtd(nand);
+ u8 *oobptr;
+ u32 i, j;
+
+ if (buf) {
+ for (i = 0; i < mtd->writesize; i++)
+ if (buf[i] != 0xff)
+ return 0;
+ }
+
+ for (i = 0; i < nand->ecc.steps; i++) {
+ oobptr = oob_fdm_ptr(nand, i);
+ for (j = 0; j < NFI_FDM_SIZE; j++)
+ if (oobptr[j] != 0xff)
+ return 0;
+ }
+
+ return 1;
+}
+
+static int mt7621_nfc_write_page_hwecc(struct mtd_info *mtd,
+ struct nand_chip *nand,
+ const u8 *buf, int oob_required,
+ int page)
+{
+ struct mt7621_nfc *nfc = nand_get_controller_data(nand);
+
+ if (mt7621_nfc_check_empty_page(nand, buf)) {
+ /*
+ * MT7621 ECC engine always generates parity code for input
+ * pages, even for empty pages. Doing so will write back ECC
+ * parity code to the oob region, which means such pages will
+ * no longer be empty pages.
+ *
+ * To avoid this, stop write operation if current page is an
+ * empty page.
+ */
+ return 0;
+ }
+
+ nand_prog_page_begin_op(nand, page, 0, NULL, 0);
+
+ nfi_write16(nfc, NFI_CNFG, FIELD_PREP(CNFG_OP_MODE, CNFG_OP_CUSTOM) |
+ CNFG_AUTO_FMT_EN | CNFG_HW_ECC_EN);
+
+ mt7621_ecc_encoder_op(nfc, true);
+
+ mt7621_nfc_write_fdm(nfc);
+
+ nfi_write16(nfc, NFI_CON, FIELD_PREP(CON_NFI_SEC, nand->ecc.steps) |
+ CON_NFI_BWR);
+
+ if (buf)
+ mt7621_nfc_write_data(nfc, buf, mtd->writesize);
+ else
+ mt7621_nfc_write_data_empty(nfc, mtd->writesize);
+
+ mt7621_nfc_wait_write_completion(nfc, nand);
+
+ mt7621_ecc_encoder_op(nfc, false);
+
+ nfi_write16(nfc, NFI_CON, 0);
+
+ return nand_prog_page_end_op(nand);
+}
+
+static int mt7621_nfc_write_page_raw(struct mtd_info *mtd,
+ struct nand_chip *nand,
+ const u8 *buf, int oob_required,
+ int page)
+{
+ struct mt7621_nfc *nfc = nand_get_controller_data(nand);
+ int i;
+
+ nand_prog_page_begin_op(nand, page, 0, NULL, 0);
+
+ nfi_write16(nfc, NFI_CNFG, FIELD_PREP(CNFG_OP_MODE, CNFG_OP_CUSTOM));
+
+ nfi_write16(nfc, NFI_CON, FIELD_PREP(CON_NFI_SEC, nand->ecc.steps) |
+ CON_NFI_BWR);
+
+ for (i = 0; i < nand->ecc.steps; i++) {
+ /* Write data */
+ if (buf)
+ mt7621_nfc_write_data(nfc, page_data_ptr(nand, buf, i),
+ nand->ecc.size);
+ else
+ mt7621_nfc_write_data_empty(nfc, nand->ecc.size);
+
+ /* Write FDM */
+ mt7621_nfc_write_data(nfc, oob_fdm_ptr(nand, i),
+ NFI_FDM_SIZE);
+
+ /* Write dummy ECC parity data */
+ mt7621_nfc_write_data_empty(nfc, nfc->spare_per_sector -
+ NFI_FDM_SIZE);
+ }
+
+ mt7621_nfc_wait_write_completion(nfc, nand);
+
+ nfi_write16(nfc, NFI_CON, 0);
+
+ return nand_prog_page_end_op(nand);
+}
+
+static int mt7621_nfc_write_oob_hwecc(struct mtd_info *mtd,
+ struct nand_chip *nand, int page)
+{
+ return mt7621_nfc_write_page_hwecc(mtd, nand, NULL, 1, page);
+}
+
+static int mt7621_nfc_write_oob_raw(struct mtd_info *mtd,
+ struct nand_chip *nand, int page)
+{
+ return mt7621_nfc_write_page_raw(mtd, nand, NULL, 1, page);
+}
+
+static int mt7621_nfc_ooblayout_free(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oob_region)
+{
+ struct nand_chip *nand = mtd_to_nand(mtd);
+
+ if (section >= nand->ecc.steps)
+ return -ERANGE;
+
+ oob_region->length = NFI_FDM_SIZE - 1;
+ oob_region->offset = section * NFI_FDM_SIZE + 1;
+
+ return 0;
+}
+
+static int mt7621_nfc_ooblayout_ecc(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oob_region)
+{
+ struct nand_chip *nand = mtd_to_nand(mtd);
+
+ if (section)
+ return -ERANGE;
+
+ oob_region->offset = NFI_FDM_SIZE * nand->ecc.steps;
+ oob_region->length = mtd->oobsize - oob_region->offset;
+
+ return 0;
+}
+
+static const struct mtd_ooblayout_ops mt7621_nfc_ooblayout_ops = {
+ .rfree = mt7621_nfc_ooblayout_free,
+ .ecc = mt7621_nfc_ooblayout_ecc,
+};
+
+/*
+ * This function will override the default one which is not supposed to be
+ * used for ECC syndrome based pages.
+ */
+static int mt7621_nfc_block_bad(struct mtd_info *mtd, loff_t ofs)
+{
+ struct nand_chip *nand = mtd_to_nand(mtd);
+ struct mtd_oob_ops ops;
+ int ret, i = 0;
+ u16 bad;
+
+ memset(&ops, 0, sizeof(ops));
+ ops.oobbuf = (uint8_t *)&bad;
+ ops.ooboffs = nand->badblockpos;
+ if (nand->options & NAND_BUSWIDTH_16) {
+ ops.ooboffs &= ~0x01;
+ ops.ooblen = 2;
+ } else {
+ ops.ooblen = 1;
+ }
+ ops.mode = MTD_OPS_RAW;
+
+ /* Read from first/last page(s) if necessary */
+ if (nand->bbt_options & NAND_BBT_SCANLASTPAGE)
+ ofs += mtd->erasesize - mtd->writesize;
+
+ do {
+ ret = mtd_read_oob(mtd, ofs, &ops);
+ if (ret)
+ return ret;
+
+ if (likely(nand->badblockbits == 8))
+ ret = bad != 0xFF;
+ else
+ ret = hweight8(bad) < nand->badblockbits;
+
+ i++;
+ ofs += mtd->writesize;
+ } while (!ret && (nand->bbt_options & NAND_BBT_SCAN2NDPAGE) && i < 2);
+
+ return ret;
+}
+
+static void mt7621_nfc_init_chip(struct mt7621_nfc *nfc)
+{
+ struct nand_chip *nand = &nfc->nand;
+ struct mtd_info *mtd;
+ int ret;
+
+ nand_set_controller_data(nand, nfc);
+
+ nand->options |= NAND_NO_SUBPAGE_WRITE;
+
+ nand->ecc.mode = NAND_ECC_HW_SYNDROME;
+ nand->ecc.read_page = mt7621_nfc_read_page_hwecc;
+ nand->ecc.read_page_raw = mt7621_nfc_read_page_raw;
+ nand->ecc.write_page = mt7621_nfc_write_page_hwecc;
+ nand->ecc.write_page_raw = mt7621_nfc_write_page_raw;
+ nand->ecc.read_oob = mt7621_nfc_read_oob_hwecc;
+ nand->ecc.read_oob_raw = mt7621_nfc_read_oob_raw;
+ nand->ecc.write_oob = mt7621_nfc_write_oob_hwecc;
+ nand->ecc.write_oob_raw = mt7621_nfc_write_oob_raw;
+
+ nand->dev_ready = mt7621_nfc_dev_ready;
+ nand->select_chip = mt7621_nfc_select_chip;
+ nand->write_byte = mt7621_nfc_write_byte;
+ nand->write_buf = mt7621_nfc_write_buf;
+ nand->read_byte = mt7621_nfc_read_byte;
+ nand->read_buf = mt7621_nfc_read_buf;
+ nand->cmd_ctrl = mt7621_nfc_cmd_ctrl;
+ nand->block_bad = mt7621_nfc_block_bad;
+
+ mtd = nand_to_mtd(nand);
+ mtd_set_ooblayout(mtd, &mt7621_nfc_ooblayout_ops);
+
+ /* Reset NFI master */
+ mt7621_nfc_hw_init(nfc);
+
+ ret = nand_scan_ident(mtd, 1, NULL);
+ if (ret)
+ return;
+
+ mt7621_nfc_attach_chip(nand);
+
+ ret = nand_scan_tail(mtd);
+ if (ret)
+ return;
+
+ nand_register(0, mtd);
+}
+
+static void mt7621_nfc_set_regs(struct mt7621_nfc *nfc)
+{
+ nfc->nfi_regs = (void __iomem *)CKSEG1ADDR(NFI_BASE);
+ nfc->ecc_regs = (void __iomem *)CKSEG1ADDR(NFI_ECC_BASE);
+}
+
+void mt7621_nfc_spl_init(struct mt7621_nfc *nfc)
+{
+ struct nand_chip *nand = &nfc->nand;
+
+ mt7621_nfc_set_regs(nfc);
+
+ nand_set_controller_data(nand, nfc);
+
+ nand->options |= NAND_NO_SUBPAGE_WRITE;
+
+ nand->ecc.mode = NAND_ECC_HW_SYNDROME;
+ nand->ecc.read_page = mt7621_nfc_read_page_hwecc;
+
+ nand->dev_ready = mt7621_nfc_dev_ready;
+ nand->select_chip = mt7621_nfc_select_chip;
+ nand->read_byte = mt7621_nfc_read_byte;
+ nand->read_buf = mt7621_nfc_read_buf;
+ nand->cmd_ctrl = mt7621_nfc_cmd_ctrl;
+
+ /* Reset NFI master */
+ mt7621_nfc_hw_init(nfc);
+}
+
+int mt7621_nfc_spl_post_init(struct mt7621_nfc *nfc)
+{
+ struct nand_chip *nand = &nfc->nand;
+ int nand_maf_id, nand_dev_id;
+ struct nand_flash_dev *type;
+
+ type = nand_get_flash_type(&nand->mtd, nand, &nand_maf_id,
+ &nand_dev_id, NULL);
+
+ if (IS_ERR(type))
+ return PTR_ERR(type);
+
+ nand->numchips = 1;
+ nand->mtd.size = nand->chipsize;
+
+ return mt7621_nfc_attach_chip(nand);
+}
+
+void board_nand_init(void)
+{
+ mt7621_nfc_set_regs(&nfc_dev);
+ mt7621_nfc_init_chip(&nfc_dev);
+}