nand: raw: add support for MediaTek MT7621 SoC
authorWeijie Gao <weijie.gao@mediatek.com>
Fri, 20 May 2022 03:23:47 +0000 (11:23 +0800)
committerDaniel Schwierzeck <daniel.schwierzeck@gmail.com>
Wed, 13 Jul 2022 21:03:37 +0000 (23:03 +0200)
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.

Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
drivers/mtd/nand/raw/Kconfig
drivers/mtd/nand/raw/Makefile
drivers/mtd/nand/raw/mt7621_nand.c [new file with mode: 0644]
drivers/mtd/nand/raw/mt7621_nand.h [new file with mode: 0644]
drivers/mtd/nand/raw/mt7621_nand_spl.c [new file with mode: 0644]

index 190300f..ce67d1a 100644 (file)
@@ -526,12 +526,25 @@ config TEGRA_NAND
        help
          Enables support for NAND Flash chips on Tegra SoCs platforms.
 
+config NAND_MT7621
+       bool "Support for MediaTek MT7621 NAND flash controller"
+       depends on SOC_MT7621
+       select SYS_NAND_SELF_INIT
+       select SPL_SYS_NAND_SELF_INIT
+       imply CMD_NAND
+       help
+         This enables NAND driver for the NAND flash controller on MediaTek
+         MT7621 platform.
+         The controller supports 4~12 bits correction per 512 bytes with a
+         maximum 4KB page size.
+
 comment "Generic NAND options"
 
 config SYS_NAND_BLOCK_SIZE
        hex "NAND chip eraseblock size"
        depends on ARCH_SUNXI || SPL_NAND_SUPPORT || TPL_NAND_SUPPORT
-       depends on !NAND_MXS && !NAND_DENALI_DT && !NAND_LPC32XX_MLC && !NAND_FSL_IFC
+       depends on !NAND_MXS && !NAND_DENALI_DT && !NAND_LPC32XX_MLC && \
+               !NAND_FSL_IFC && !NAND_MT7621
        help
          Number of data bytes in one eraseblock for the NAND chip on the
          board. This is the multiple of NAND_PAGE_SIZE and the number of
@@ -556,7 +569,7 @@ config SYS_NAND_PAGE_SIZE
        depends on ARCH_SUNXI || NAND_OMAP_GPMC || NAND_LPC32XX_SLC || \
                SPL_NAND_SIMPLE || (NAND_MXC && SPL_NAND_SUPPORT) || \
                (NAND_ATMEL && SPL_NAND_SUPPORT) || SPL_GENERATE_ATMEL_PMECC_HEADER
-       depends on !NAND_MXS && !NAND_DENALI_DT && !NAND_LPC32XX_MLC
+       depends on !NAND_MXS && !NAND_DENALI_DT && !NAND_LPC32XX_MLC && !NAND_MT7621
        help
          Number of data bytes in one page for the NAND chip on the
          board, not including the OOB area.
index e3f6b90..f278f31 100644 (file)
@@ -72,6 +72,7 @@ obj-$(CONFIG_NAND_ZYNQ) += zynq_nand.o
 obj-$(CONFIG_NAND_STM32_FMC2) += stm32_fmc2_nand.o
 obj-$(CONFIG_CORTINA_NAND) += cortina_nand.o
 obj-$(CONFIG_ROCKCHIP_NAND) += rockchip_nfc.o
+obj-$(CONFIG_NAND_MT7621) += mt7621_nand.o
 
 else  # minimal SPL drivers
 
@@ -80,5 +81,6 @@ obj-$(CONFIG_NAND_FSL_IFC) += fsl_ifc_spl.o
 obj-$(CONFIG_NAND_MXC) += mxc_nand_spl.o
 obj-$(CONFIG_NAND_MXS) += mxs_nand_spl.o mxs_nand.o
 obj-$(CONFIG_NAND_SUNXI) += sunxi_nand_spl.o
+obj-$(CONFIG_NAND_MT7621) += mt7621_nand_spl.o mt7621_nand.o
 
 endif # drivers
diff --git a/drivers/mtd/nand/raw/mt7621_nand.c b/drivers/mtd/nand/raw/mt7621_nand.c
new file mode 100644 (file)
index 0000000..2fd8934
--- /dev/null
@@ -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);
+}
diff --git a/drivers/mtd/nand/raw/mt7621_nand.h b/drivers/mtd/nand/raw/mt7621_nand.h
new file mode 100644 (file)
index 0000000..af4bc55
--- /dev/null
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2022 MediaTek Inc. All rights reserved.
+ *
+ * Author: Weijie Gao <weijie.gao@mediatek.com>
+ */
+
+#ifndef _MT7621_NAND_H_
+#define _MT7621_NAND_H_
+
+#include <linux/types.h>
+#include <linux/mtd/mtd.h>
+#include <linux/compiler.h>
+#include <linux/mtd/rawnand.h>
+
+struct mt7621_nfc {
+       struct nand_chip nand;
+
+       void __iomem *nfi_regs;
+       void __iomem *ecc_regs;
+
+       u32 spare_per_sector;
+};
+
+/* for SPL */
+void mt7621_nfc_spl_init(struct mt7621_nfc *nfc);
+int mt7621_nfc_spl_post_init(struct mt7621_nfc *nfc);
+
+#endif /* _MT7621_NAND_H_ */
diff --git a/drivers/mtd/nand/raw/mt7621_nand_spl.c b/drivers/mtd/nand/raw/mt7621_nand_spl.c
new file mode 100644 (file)
index 0000000..114fc8b
--- /dev/null
@@ -0,0 +1,237 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022 MediaTek Inc. All rights reserved.
+ *
+ * Author: Weijie Gao <weijie.gao@mediatek.com>
+ */
+
+#include <image.h>
+#include <malloc.h>
+#include <linux/sizes.h>
+#include <linux/delay.h>
+#include <linux/mtd/rawnand.h>
+#include "mt7621_nand.h"
+
+static struct mt7621_nfc nfc_dev;
+static u8 *buffer;
+static int nand_valid;
+
+static void nand_command_lp(struct mtd_info *mtd, unsigned int command,
+                           int column, int page_addr)
+{
+       register struct nand_chip *chip = mtd_to_nand(mtd);
+
+       /* Command latch cycle */
+       chip->cmd_ctrl(mtd, command, NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
+
+       if (column != -1 || page_addr != -1) {
+               int ctrl = NAND_CTRL_CHANGE | NAND_NCE | NAND_ALE;
+
+               /* Serially input address */
+               if (column != -1) {
+                       chip->cmd_ctrl(mtd, column, ctrl);
+                       ctrl &= ~NAND_CTRL_CHANGE;
+                       if (command != NAND_CMD_READID)
+                               chip->cmd_ctrl(mtd, column >> 8, ctrl);
+               }
+               if (page_addr != -1) {
+                       chip->cmd_ctrl(mtd, page_addr, ctrl);
+                       chip->cmd_ctrl(mtd, page_addr >> 8,
+                                      NAND_NCE | NAND_ALE);
+                       if (chip->options & NAND_ROW_ADDR_3)
+                               chip->cmd_ctrl(mtd, page_addr >> 16,
+                                              NAND_NCE | NAND_ALE);
+               }
+       }
+       chip->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
+
+       /*
+        * Program and erase have their own busy handlers status, sequential
+        * in and status need no delay.
+        */
+       switch (command) {
+       case NAND_CMD_STATUS:
+       case NAND_CMD_READID:
+       case NAND_CMD_SET_FEATURES:
+               return;
+
+       case NAND_CMD_READ0:
+               chip->cmd_ctrl(mtd, NAND_CMD_READSTART,
+                              NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
+               chip->cmd_ctrl(mtd, NAND_CMD_NONE,
+                              NAND_NCE | NAND_CTRL_CHANGE);
+       }
+
+       /*
+        * Apply this short delay always to ensure that we do wait tWB in
+        * any case on any machine.
+        */
+       ndelay(100);
+
+       nand_wait_ready(mtd);
+}
+
+static int nfc_read_page_hwecc(struct mtd_info *mtd, void *buf,
+                              unsigned int page)
+{
+       struct nand_chip *chip = mtd_to_nand(mtd);
+       int ret;
+
+       chip->cmdfunc(mtd, NAND_CMD_READ0, 0x0, page);
+
+       ret = chip->ecc.read_page(mtd, chip, buf, 1, page);
+       if (ret < 0 || ret > chip->ecc.strength)
+               return -1;
+
+       return 0;
+}
+
+static int nfc_read_oob_hwecc(struct mtd_info *mtd, void *buf, u32 len,
+                             unsigned int page)
+{
+       struct nand_chip *chip = mtd_to_nand(mtd);
+       int ret;
+
+       chip->cmdfunc(mtd, NAND_CMD_READ0, 0x0, page);
+
+       ret = chip->ecc.read_page(mtd, chip, NULL, 1, page);
+       if (ret < 0)
+               return -1;
+
+       if (len > mtd->oobsize)
+               len = mtd->oobsize;
+
+       memcpy(buf, chip->oob_poi, len);
+
+       return 0;
+}
+
+static int nfc_check_bad_block(struct mtd_info *mtd, unsigned int page)
+{
+       struct nand_chip *chip = mtd_to_nand(mtd);
+       u32 pages_per_block, i = 0;
+       int ret;
+       u8 bad;
+
+       pages_per_block = 1 << (mtd->erasesize_shift - mtd->writesize_shift);
+
+       /* Read from first/last page(s) if necessary */
+       if (chip->bbt_options & NAND_BBT_SCANLASTPAGE) {
+               page += pages_per_block - 1;
+               if (chip->bbt_options & NAND_BBT_SCAN2NDPAGE)
+                       page--;
+       }
+
+       do {
+               ret = nfc_read_oob_hwecc(mtd, &bad, 1, page);
+               if (ret)
+                       return ret;
+
+               ret = bad != 0xFF;
+
+               i++;
+               page++;
+       } while (!ret && (chip->bbt_options & NAND_BBT_SCAN2NDPAGE) && i < 2);
+
+       return ret;
+}
+
+int nand_spl_load_image(uint32_t offs, unsigned int size, void *dest)
+{
+       struct mt7621_nfc *nfc = &nfc_dev;
+       struct nand_chip *chip = &nfc->nand;
+       struct mtd_info *mtd = &chip->mtd;
+       u32 addr, col, page, chksz;
+       bool check_bad = true;
+
+       if (!nand_valid)
+               return -ENODEV;
+
+       while (size) {
+               if (check_bad || !(offs & mtd->erasesize_mask)) {
+                       addr = offs & (~mtd->erasesize_mask);
+                       page = addr >> mtd->writesize_shift;
+                       if (nfc_check_bad_block(mtd, page)) {
+                               /* Skip bad block */
+                               if (addr >= mtd->size - mtd->erasesize)
+                                       return -1;
+
+                               offs += mtd->erasesize;
+                               continue;
+                       }
+
+                       check_bad = false;
+               }
+
+               col = offs & mtd->writesize_mask;
+               page = offs >> mtd->writesize_shift;
+               chksz = min(mtd->writesize - col, (uint32_t)size);
+
+               if (unlikely(chksz < mtd->writesize)) {
+                       /* Not reading a full page */
+                       if (nfc_read_page_hwecc(mtd, buffer, page))
+                               return -1;
+
+                       memcpy(dest, buffer + col, chksz);
+               } else {
+                       if (nfc_read_page_hwecc(mtd, dest, page))
+                               return -1;
+               }
+
+               dest += chksz;
+               offs += chksz;
+               size -= chksz;
+       }
+
+       return 0;
+}
+
+int nand_default_bbt(struct mtd_info *mtd)
+{
+       return 0;
+}
+
+unsigned long nand_size(void)
+{
+       if (!nand_valid)
+               return 0;
+
+       /* Unlikely that NAND size > 2GBytes */
+       if (nfc_dev.nand.chipsize <= SZ_2G)
+               return nfc_dev.nand.chipsize;
+
+       return SZ_2G;
+}
+
+void nand_deselect(void)
+{
+}
+
+void nand_init(void)
+{
+       struct mtd_info *mtd;
+       struct nand_chip *chip;
+
+       if (nand_valid)
+               return;
+
+       mt7621_nfc_spl_init(&nfc_dev);
+
+       chip = &nfc_dev.nand;
+       mtd = &chip->mtd;
+       chip->cmdfunc = nand_command_lp;
+
+       if (mt7621_nfc_spl_post_init(&nfc_dev))
+               return;
+
+       mtd->erasesize_shift = ffs(mtd->erasesize) - 1;
+       mtd->writesize_shift = ffs(mtd->writesize) - 1;
+       mtd->erasesize_mask = (1 << mtd->erasesize_shift) - 1;
+       mtd->writesize_mask = (1 << mtd->writesize_shift) - 1;
+
+       buffer = malloc(mtd->writesize);
+       if (!buffer)
+               return;
+
+       nand_valid = 1;
+}