[PATCH 2/2] mtd: nand: Add driver for NAND controller on STM32MP SoCs
Alexander Shiyan
eagle.alexander923 at gmail.com
Thu Aug 3 03:32:38 PDT 2023
This adds support for NAND controller on STM32MP SoCs.
The original source is taken from the STMicroelectronics/u-boot repository [1].
[1] https://github.com/STMicroelectronics/u-boot/blob/v2022.10-stm32mp/drivers/mtd/nand/raw/stm32_fmc2_nand.c
Signed-off-by: Alexander Shiyan <eagle.alexander923 at gmail.com>
---
drivers/mtd/nand/Kconfig | 10 +
drivers/mtd/nand/Makefile | 1 +
drivers/mtd/nand/nand_stm32.c | 1036 +++++++++++++++++++++++++++++++++
3 files changed, 1047 insertions(+)
create mode 100644 drivers/mtd/nand/nand_stm32.c
diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index d4b941d20c..3237b4233f 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -95,6 +95,16 @@ config NAND_MRVL_NFC
Support for the PXA3xx NAND controller, present in Armada 370/XP and
PXA3xx SoCs.
+config NAND_STM32
+ bool "Support for NAND controller on STM32MP SoCs"
+ depends on ARCH_STM32MP || COMPILE_TEST
+ select STM32_FMC2_EBI if ARCH_STM32MP
+ help
+ Enables support for NAND Flash chips on SoCs containing the FMC2
+ NAND controller. This controller is found on STM32MP SoCs.
+ The controller supports a maximum 8k page size and supports
+ a maximum 8-bit correction error per sector of 512 bytes.
+
config NAND_ATMEL
bool
prompt "Atmel (AT91SAM9xxx) NAND driver"
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index 6258eb2177..8142d67116 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_NAND_IMX) += nand_imx.o
obj-$(CONFIG_NAND_OMAP_GPMC) += nand_omap_gpmc.o nand_omap_bch_decoder.o
obj-$(CONFIG_MTD_NAND_OMAP_ELM) += omap_elm.o
obj-$(CONFIG_NAND_ORION) += nand_orion.o
+obj-$(CONFIG_NAND_STM32) += nand_stm32.o
obj-$(CONFIG_NAND_MRVL_NFC) += nand_mrvl_nfc.o
obj-$(CONFIG_NAND_ATMEL) += atmel/
obj-$(CONFIG_NAND_MXS) += nand_mxs.o
diff --git a/drivers/mtd/nand/nand_stm32.c b/drivers/mtd/nand/nand_stm32.c
new file mode 100644
index 0000000000..be13543a97
--- /dev/null
+++ b/drivers/mtd/nand/nand_stm32.c
@@ -0,0 +1,1036 @@
+// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
+/*
+ * Copyright (C) STMicroelectronics 2019
+ * Author: Christophe Kerello <christophe.kerello at st.com>
+ */
+
+#define pr_fmt(fmt) "nand-stm32: " fmt
+
+#include <common.h>
+#include <init.h>
+#include <of_address.h>
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/gpio/consumer.h>
+#include <linux/iopoll.h>
+#include <linux/reset.h>
+
+#include "internals.h"
+
+/* Bad block marker length */
+#define FMC2_BBM_LEN 2
+
+/* ECC step size */
+#define FMC2_ECC_STEP_SIZE 512
+
+/* Command delay */
+#define FMC2_RB_DELAY_US 30
+
+/* Max chip enable */
+#define FMC2_MAX_CE 2
+
+/* Timings */
+#define FMC2_THIZ 1
+#define FMC2_TIO 8000
+#define FMC2_TSYNC 3000
+#define FMC2_PCR_TIMING_MASK 0xf
+#define FMC2_PMEM_PATT_TIMING_MASK 0xff
+
+/* FMC2 Controller Registers */
+#define FMC2_BCR1 0x0
+#define FMC2_PCR 0x80
+#define FMC2_SR 0x84
+#define FMC2_PMEM 0x88
+#define FMC2_PATT 0x8c
+#define FMC2_HECCR 0x94
+#define FMC2_BCHISR 0x254
+#define FMC2_BCHICR 0x258
+#define FMC2_BCHPBR1 0x260
+#define FMC2_BCHPBR2 0x264
+#define FMC2_BCHPBR3 0x268
+#define FMC2_BCHPBR4 0x26c
+#define FMC2_BCHDSR0 0x27c
+#define FMC2_BCHDSR1 0x280
+#define FMC2_BCHDSR2 0x284
+#define FMC2_BCHDSR3 0x288
+#define FMC2_BCHDSR4 0x28c
+
+/* Register: FMC2_BCR1 */
+#define FMC2_BCR1_FMC2EN BIT(31)
+
+/* Register: FMC2_PCR */
+#define FMC2_PCR_PWAITEN BIT(1)
+#define FMC2_PCR_PBKEN BIT(2)
+#define FMC2_PCR_PWID GENMASK(5, 4)
+#define FMC2_PCR_PWID_BUSWIDTH_8 0
+#define FMC2_PCR_PWID_BUSWIDTH_16 1
+#define FMC2_PCR_ECCEN BIT(6)
+#define FMC2_PCR_ECCALG BIT(8)
+#define FMC2_PCR_TCLR GENMASK(12, 9)
+#define FMC2_PCR_TCLR_DEFAULT 0xf
+#define FMC2_PCR_TAR GENMASK(16, 13)
+#define FMC2_PCR_TAR_DEFAULT 0xf
+#define FMC2_PCR_ECCSS GENMASK(19, 17)
+#define FMC2_PCR_ECCSS_512 1
+#define FMC2_PCR_ECCSS_2048 3
+#define FMC2_PCR_BCHECC BIT(24)
+#define FMC2_PCR_WEN BIT(25)
+
+/* Register: FMC2_SR */
+#define FMC2_SR_NWRF BIT(6)
+
+/* Register: FMC2_PMEM */
+#define FMC2_PMEM_MEMSET GENMASK(7, 0)
+#define FMC2_PMEM_MEMWAIT GENMASK(15, 8)
+#define FMC2_PMEM_MEMHOLD GENMASK(23, 16)
+#define FMC2_PMEM_MEMHIZ GENMASK(31, 24)
+#define FMC2_PMEM_DEFAULT 0x0a0a0a0a
+
+/* Register: FMC2_PATT */
+#define FMC2_PATT_ATTSET GENMASK(7, 0)
+#define FMC2_PATT_ATTWAIT GENMASK(15, 8)
+#define FMC2_PATT_ATTHOLD GENMASK(23, 16)
+#define FMC2_PATT_ATTHIZ GENMASK(31, 24)
+#define FMC2_PATT_DEFAULT 0x0a0a0a0a
+
+/* Register: FMC2_BCHISR */
+#define FMC2_BCHISR_DERF BIT(1)
+#define FMC2_BCHISR_EPBRF BIT(4)
+
+/* Register: FMC2_BCHICR */
+#define FMC2_BCHICR_CLEAR_IRQ GENMASK(4, 0)
+
+/* Register: FMC2_BCHDSR0 */
+#define FMC2_BCHDSR0_DUE BIT(0)
+#define FMC2_BCHDSR0_DEF BIT(1)
+#define FMC2_BCHDSR0_DEN GENMASK(7, 4)
+
+/* Register: FMC2_BCHDSR1 */
+#define FMC2_BCHDSR1_EBP1 GENMASK(12, 0)
+#define FMC2_BCHDSR1_EBP2 GENMASK(28, 16)
+
+/* Register: FMC2_BCHDSR2 */
+#define FMC2_BCHDSR2_EBP3 GENMASK(12, 0)
+#define FMC2_BCHDSR2_EBP4 GENMASK(28, 16)
+
+/* Register: FMC2_BCHDSR3 */
+#define FMC2_BCHDSR3_EBP5 GENMASK(12, 0)
+#define FMC2_BCHDSR3_EBP6 GENMASK(28, 16)
+
+/* Register: FMC2_BCHDSR4 */
+#define FMC2_BCHDSR4_EBP7 GENMASK(12, 0)
+#define FMC2_BCHDSR4_EBP8 GENMASK(28, 16)
+
+#define FMC2_TIMEOUT_5S 5000000
+
+enum stm32_fmc2_ecc {
+ FMC2_ECC_HAM = 1,
+ FMC2_ECC_BCH4 = 4,
+ FMC2_ECC_BCH8 = 8
+};
+
+struct stm32_fmc2_timings {
+ u8 tclr;
+ u8 tar;
+ u8 thiz;
+ u8 twait;
+ u8 thold_mem;
+ u8 tset_mem;
+ u8 thold_att;
+ u8 tset_att;
+};
+
+struct stm32_fmc2_nand {
+ struct nand_chip chip;
+ struct stm32_fmc2_timings timings;
+ int wp_gpio;
+ int ncs;
+ int cs_used[FMC2_MAX_CE];
+};
+
+static inline struct stm32_fmc2_nand *to_fmc2_nand(struct nand_chip *chip)
+{
+ return container_of(chip, struct stm32_fmc2_nand, chip);
+}
+
+struct stm32_fmc2_nfc {
+ struct stm32_fmc2_nand nand;
+ struct nand_ecclayout ecclayout;
+ void __iomem *io_base;
+ void __iomem *data_base[FMC2_MAX_CE];
+ void __iomem *cmd_base[FMC2_MAX_CE];
+ void __iomem *addr_base[FMC2_MAX_CE];
+ struct clk *clk;
+
+ u8 cs_assigned;
+ int cs_sel;
+};
+
+static void stm32_fmc2_nfc_timings_init(struct nand_chip *chip)
+{
+ struct stm32_fmc2_nfc *nfc = (struct stm32_fmc2_nfc *)chip->priv;
+ struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
+ struct stm32_fmc2_timings *timings = &nand->timings;
+ u32 pmem, patt;
+
+ /* Set tclr/tar timings */
+ clrsetbits_le32(nfc->io_base + FMC2_PCR,
+ FMC2_PCR_TCLR | FMC2_PCR_TAR,
+ FIELD_PREP(FMC2_PCR_TCLR, timings->tclr) |
+ FIELD_PREP(FMC2_PCR_TAR, timings->tar));
+
+ /* Set tset/twait/thold/thiz timings in common bank */
+ pmem = FIELD_PREP(FMC2_PMEM_MEMSET, timings->tset_mem);
+ pmem |= FIELD_PREP(FMC2_PMEM_MEMWAIT, timings->twait);
+ pmem |= FIELD_PREP(FMC2_PMEM_MEMHOLD, timings->thold_mem);
+ pmem |= FIELD_PREP(FMC2_PMEM_MEMHIZ, timings->thiz);
+ writel(pmem, nfc->io_base + FMC2_PMEM);
+
+ /* Set tset/twait/thold/thiz timings in attribut bank */
+ patt = FIELD_PREP(FMC2_PATT_ATTSET, timings->tset_att);
+ patt |= FIELD_PREP(FMC2_PATT_ATTWAIT, timings->twait);
+ patt |= FIELD_PREP(FMC2_PATT_ATTHOLD, timings->thold_att);
+ patt |= FIELD_PREP(FMC2_PATT_ATTHIZ, timings->thiz);
+ writel(patt, nfc->io_base + FMC2_PATT);
+}
+
+static void stm32_fmc2_nfc_setup(struct nand_chip *chip)
+{
+ struct stm32_fmc2_nfc *nfc = (struct stm32_fmc2_nfc *)chip->priv;
+ u32 pcr = 0, pcr_mask;
+
+ /* Configure ECC algorithm (default configuration is Hamming) */
+ pcr_mask = FMC2_PCR_ECCALG;
+ pcr_mask |= FMC2_PCR_BCHECC;
+ if (chip->ecc.strength == FMC2_ECC_BCH8) {
+ pcr |= FMC2_PCR_ECCALG;
+ pcr |= FMC2_PCR_BCHECC;
+ } else if (chip->ecc.strength == FMC2_ECC_BCH4) {
+ pcr |= FMC2_PCR_ECCALG;
+ }
+
+ /* Set buswidth */
+ pcr_mask |= FMC2_PCR_PWID;
+ if (chip->options & NAND_BUSWIDTH_16)
+ pcr |= FIELD_PREP(FMC2_PCR_PWID, FMC2_PCR_PWID_BUSWIDTH_16);
+
+ /* Set ECC sector size */
+ pcr_mask |= FMC2_PCR_ECCSS;
+ pcr |= FIELD_PREP(FMC2_PCR_ECCSS, FMC2_PCR_ECCSS_512);
+
+ clrsetbits_le32(nfc->io_base + FMC2_PCR, pcr_mask, pcr);
+}
+
+static void stm32_fmc2_nfc_select_chip(struct nand_chip *chip, int chipnr)
+{
+ struct stm32_fmc2_nfc *nfc = (struct stm32_fmc2_nfc *)chip->priv;
+ struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
+
+ if (chipnr < 0 || chipnr >= nand->ncs)
+ return;
+
+ if (nand->cs_used[chipnr] == nfc->cs_sel)
+ return;
+
+ nfc->cs_sel = nand->cs_used[chipnr];
+ chip->legacy.IO_ADDR_R = nfc->data_base[nfc->cs_sel];
+ chip->legacy.IO_ADDR_W = nfc->data_base[nfc->cs_sel];
+
+ stm32_fmc2_nfc_setup(chip);
+ stm32_fmc2_nfc_timings_init(chip);
+}
+
+static void stm32_fmc2_nfc_set_buswidth_16(struct stm32_fmc2_nfc *nfc,
+ bool set)
+{
+ u32 pcr;
+
+ pcr = set ? FIELD_PREP(FMC2_PCR_PWID, FMC2_PCR_PWID_BUSWIDTH_16) :
+ FIELD_PREP(FMC2_PCR_PWID, FMC2_PCR_PWID_BUSWIDTH_8);
+
+ clrsetbits_le32(nfc->io_base + FMC2_PCR, FMC2_PCR_PWID, pcr);
+}
+
+static void stm32_fmc2_nfc_set_ecc(struct stm32_fmc2_nfc *nfc, bool enable)
+{
+ clrsetbits_le32(nfc->io_base + FMC2_PCR, FMC2_PCR_ECCEN,
+ enable ? FMC2_PCR_ECCEN : 0);
+}
+
+static void stm32_fmc2_nfc_clear_bch_irq(struct stm32_fmc2_nfc *nfc)
+{
+ writel(FMC2_BCHICR_CLEAR_IRQ, nfc->io_base + FMC2_BCHICR);
+}
+
+static void stm32_fmc2_nfc_cmd_ctrl(struct nand_chip *chip, int cmd,
+ unsigned int ctrl)
+{
+ struct stm32_fmc2_nfc *nfc = (struct stm32_fmc2_nfc *)chip->priv;
+
+ if (cmd == NAND_CMD_NONE)
+ return;
+
+ if (ctrl & NAND_CLE) {
+ writeb(cmd, nfc->cmd_base[nfc->cs_sel]);
+ return;
+ }
+
+ writeb(cmd, nfc->addr_base[nfc->cs_sel]);
+}
+
+/*
+ * Enable ECC logic and reset syndrome/parity bits previously calculated
+ * Syndrome/parity bits is cleared by setting the ECCEN bit to 0
+ */
+static void stm32_fmc2_nfc_hwctl(struct nand_chip *chip, int mode)
+{
+ struct stm32_fmc2_nfc *nfc = (struct stm32_fmc2_nfc *)chip->priv;
+
+ stm32_fmc2_nfc_set_ecc(nfc, false);
+
+ if (chip->ecc.strength != FMC2_ECC_HAM) {
+ clrsetbits_le32(nfc->io_base + FMC2_PCR, FMC2_PCR_WEN,
+ mode == NAND_ECC_WRITE ? FMC2_PCR_WEN : 0);
+
+ stm32_fmc2_nfc_clear_bch_irq(nfc);
+ }
+
+ stm32_fmc2_nfc_set_ecc(nfc, true);
+}
+
+/*
+ * ECC Hamming calculation
+ * ECC is 3 bytes for 512 bytes of data (supports error correction up to
+ * max of 1-bit)
+ */
+static int stm32_fmc2_nfc_ham_calculate(struct nand_chip *chip, const u8 *data,
+ u8 *ecc)
+{
+ struct stm32_fmc2_nfc *nfc = (struct stm32_fmc2_nfc *)chip->priv;
+ u32 heccr, sr;
+ int ret;
+
+ ret = readl_poll_timeout(nfc->io_base + FMC2_SR, sr,
+ sr & FMC2_SR_NWRF, FMC2_TIMEOUT_5S);
+ if (ret < 0) {
+ pr_err("Ham timeout\n");
+ return ret;
+ }
+
+ heccr = readl(nfc->io_base + FMC2_HECCR);
+
+ ecc[0] = heccr;
+ ecc[1] = heccr >> 8;
+ ecc[2] = heccr >> 16;
+
+ stm32_fmc2_nfc_set_ecc(nfc, false);
+
+ return 0;
+}
+
+static int stm32_fmc2_nfc_ham_correct(struct nand_chip *chip, u8 *dat,
+ u8 *read_ecc, u8 *calc_ecc)
+{
+ u8 bit_position = 0, b0, b1, b2;
+ u32 byte_addr = 0, b;
+ u32 i, shifting = 1;
+
+ /* Indicate which bit and byte is faulty (if any) */
+ b0 = read_ecc[0] ^ calc_ecc[0];
+ b1 = read_ecc[1] ^ calc_ecc[1];
+ b2 = read_ecc[2] ^ calc_ecc[2];
+ b = b0 | (b1 << 8) | (b2 << 16);
+
+ /* No errors */
+ if (likely(!b))
+ return 0;
+
+ /* Calculate bit position */
+ for (i = 0; i < 3; i++) {
+ switch (b % 4) {
+ case 2:
+ bit_position += shifting;
+ case 1:
+ break;
+ default:
+ return -EBADMSG;
+ }
+ shifting <<= 1;
+ b >>= 2;
+ }
+
+ /* Calculate byte position */
+ shifting = 1;
+ for (i = 0; i < 9; i++) {
+ switch (b % 4) {
+ case 2:
+ byte_addr += shifting;
+ case 1:
+ break;
+ default:
+ return -EBADMSG;
+ }
+ shifting <<= 1;
+ b >>= 2;
+ }
+
+ /* Flip the bit */
+ dat[byte_addr] ^= (1 << bit_position);
+
+ return 1;
+}
+
+/*
+ * ECC BCH calculation and correction
+ * ECC is 7/13 bytes for 512 bytes of data (supports error correction up to
+ * max of 4-bit/8-bit)
+ */
+static int stm32_fmc2_nfc_bch_calculate(struct nand_chip *chip, const u8 *data,
+ u8 *ecc)
+{
+ struct stm32_fmc2_nfc *nfc = (struct stm32_fmc2_nfc *)chip->priv;
+ u32 bchpbr, bchisr;
+ int ret;
+
+ /* Wait until the BCH code is ready */
+ ret = readl_poll_timeout(nfc->io_base + FMC2_BCHISR, bchisr,
+ bchisr & FMC2_BCHISR_EPBRF, FMC2_TIMEOUT_5S);
+ if (ret < 0) {
+ pr_err("Bch timeout\n");
+ return ret;
+ }
+
+ /* Read parity bits */
+ bchpbr = readl(nfc->io_base + FMC2_BCHPBR1);
+ ecc[0] = bchpbr;
+ ecc[1] = bchpbr >> 8;
+ ecc[2] = bchpbr >> 16;
+ ecc[3] = bchpbr >> 24;
+
+ bchpbr = readl(nfc->io_base + FMC2_BCHPBR2);
+ ecc[4] = bchpbr;
+ ecc[5] = bchpbr >> 8;
+ ecc[6] = bchpbr >> 16;
+
+ if (chip->ecc.strength == FMC2_ECC_BCH8) {
+ ecc[7] = bchpbr >> 24;
+
+ bchpbr = readl(nfc->io_base + FMC2_BCHPBR3);
+ ecc[8] = bchpbr;
+ ecc[9] = bchpbr >> 8;
+ ecc[10] = bchpbr >> 16;
+ ecc[11] = bchpbr >> 24;
+
+ bchpbr = readl(nfc->io_base + FMC2_BCHPBR4);
+ ecc[12] = bchpbr;
+ }
+
+ stm32_fmc2_nfc_set_ecc(nfc, false);
+
+ return 0;
+}
+
+static int stm32_fmc2_nfc_bch_correct(struct nand_chip *chip, u8 *dat,
+ u8 *read_ecc, u8 *calc_ecc)
+{
+ struct stm32_fmc2_nfc *nfc = (struct stm32_fmc2_nfc *)chip->priv;
+ u32 bchdsr0, bchdsr1, bchdsr2, bchdsr3, bchdsr4, bchisr;
+ u16 pos[8];
+ int i, ret, den, eccsize = chip->ecc.size;
+ unsigned int nb_errs = 0;
+
+ /* Wait until the decoding error is ready */
+ ret = readl_poll_timeout(nfc->io_base + FMC2_BCHISR, bchisr,
+ bchisr & FMC2_BCHISR_DERF, FMC2_TIMEOUT_5S);
+ if (ret < 0) {
+ pr_err("Bch timeout\n");
+ return ret;
+ }
+
+ bchdsr0 = readl(nfc->io_base + FMC2_BCHDSR0);
+ bchdsr1 = readl(nfc->io_base + FMC2_BCHDSR1);
+ bchdsr2 = readl(nfc->io_base + FMC2_BCHDSR2);
+ bchdsr3 = readl(nfc->io_base + FMC2_BCHDSR3);
+ bchdsr4 = readl(nfc->io_base + FMC2_BCHDSR4);
+
+ stm32_fmc2_nfc_set_ecc(nfc, false);
+
+ /* No errors found */
+ if (likely(!(bchdsr0 & FMC2_BCHDSR0_DEF)))
+ return 0;
+
+ /* Too many errors detected */
+ if (unlikely(bchdsr0 & FMC2_BCHDSR0_DUE))
+ return -EBADMSG;
+
+ pos[0] = FIELD_GET(FMC2_BCHDSR1_EBP1, bchdsr1);
+ pos[1] = FIELD_GET(FMC2_BCHDSR1_EBP2, bchdsr1);
+ pos[2] = FIELD_GET(FMC2_BCHDSR2_EBP3, bchdsr2);
+ pos[3] = FIELD_GET(FMC2_BCHDSR2_EBP4, bchdsr2);
+ pos[4] = FIELD_GET(FMC2_BCHDSR3_EBP5, bchdsr3);
+ pos[5] = FIELD_GET(FMC2_BCHDSR3_EBP6, bchdsr3);
+ pos[6] = FIELD_GET(FMC2_BCHDSR4_EBP7, bchdsr4);
+ pos[7] = FIELD_GET(FMC2_BCHDSR4_EBP8, bchdsr4);
+
+ den = FIELD_GET(FMC2_BCHDSR0_DEN, bchdsr0);
+ for (i = 0; i < den; i++) {
+ if (pos[i] < eccsize * 8) {
+ __change_bit(pos[i], (unsigned long *)dat);
+ nb_errs++;
+ }
+ }
+
+ return nb_errs;
+}
+
+static int stm32_fmc2_nfc_read_page(struct nand_chip *chip, u8 *buf,
+ int oob_required, int page)
+{
+ struct mtd_info *mtd = nand_to_mtd(chip);
+ int i, s, stat, eccsize = chip->ecc.size;
+ int eccbytes = chip->ecc.bytes;
+ int eccsteps = chip->ecc.steps;
+ int eccstrength = chip->ecc.strength;
+ u8 *p = buf;
+ u8 *ecc_calc = chip->ecc.calc_buf;
+ u8 *ecc_code = chip->ecc.code_buf;
+ unsigned int max_bitflips = 0;
+
+ for (i = mtd->writesize + FMC2_BBM_LEN, s = 0; s < eccsteps;
+ s++, i += eccbytes, p += eccsize) {
+ chip->ecc.hwctl(chip, NAND_ECC_READ);
+
+ /* Read the nand page sector (512 bytes) */
+ chip->legacy.cmdfunc(chip, NAND_CMD_RNDOUT, s * eccsize, -1);
+ chip->legacy.read_buf(chip, p, eccsize);
+
+ /* Read the corresponding ECC bytes */
+ chip->legacy.cmdfunc(chip, NAND_CMD_RNDOUT, i, -1);
+ chip->legacy.read_buf(chip, ecc_code, eccbytes);
+
+ /* Correct the data */
+ stat = chip->ecc.correct(chip, p, ecc_code, ecc_calc);
+ if (stat == -EBADMSG)
+ /* Check for empty pages with bitflips */
+ stat = nand_check_erased_ecc_chunk(p, eccsize,
+ ecc_code, eccbytes,
+ NULL, 0,
+ eccstrength);
+
+ if (stat < 0) {
+ mtd->ecc_stats.failed++;
+ } else {
+ mtd->ecc_stats.corrected += stat;
+ max_bitflips = max_t(unsigned int, max_bitflips, stat);
+ }
+ }
+
+ /* Read oob */
+ if (oob_required) {
+ chip->legacy.cmdfunc(chip, NAND_CMD_RNDOUT, mtd->writesize, -1);
+ chip->legacy.read_buf(chip, chip->oob_poi, mtd->oobsize);
+ }
+
+ return max_bitflips;
+}
+
+static void stm32_fmc2_nfc_init(struct stm32_fmc2_nfc *nfc, bool has_parent)
+{
+ u32 pcr = readl(nfc->io_base + FMC2_PCR);
+
+ /* Set CS used to undefined */
+ nfc->cs_sel = -1;
+
+ /* Enable wait feature and nand flash memory bank */
+ pcr |= FMC2_PCR_PWAITEN;
+ pcr |= FMC2_PCR_PBKEN;
+
+ /* Set buswidth to 8 bits mode for identification */
+ pcr &= ~FMC2_PCR_PWID;
+
+ /* ECC logic is disabled */
+ pcr &= ~FMC2_PCR_ECCEN;
+
+ /* Default mode */
+ pcr &= ~FMC2_PCR_ECCALG;
+ pcr &= ~FMC2_PCR_BCHECC;
+ pcr &= ~FMC2_PCR_WEN;
+
+ /* Set default ECC sector size */
+ pcr &= ~FMC2_PCR_ECCSS;
+ pcr |= FIELD_PREP(FMC2_PCR_ECCSS, FMC2_PCR_ECCSS_2048);
+
+ /* Set default tclr/tar timings */
+ pcr &= ~FMC2_PCR_TCLR;
+ pcr |= FIELD_PREP(FMC2_PCR_TCLR, FMC2_PCR_TCLR_DEFAULT);
+ pcr &= ~FMC2_PCR_TAR;
+ pcr |= FIELD_PREP(FMC2_PCR_TAR, FMC2_PCR_TAR_DEFAULT);
+
+ /* Enable FMC2 controller */
+ if (!has_parent)
+ setbits_le32(nfc->io_base + FMC2_BCR1, FMC2_BCR1_FMC2EN);
+
+ writel(pcr, nfc->io_base + FMC2_PCR);
+ writel(FMC2_PMEM_DEFAULT, nfc->io_base + FMC2_PMEM);
+ writel(FMC2_PATT_DEFAULT, nfc->io_base + FMC2_PATT);
+}
+
+static void stm32_fmc2_nfc_calc_timings(struct nand_chip *chip,
+ const struct nand_sdr_timings *sdrt)
+{
+ struct stm32_fmc2_nfc *nfc = (struct stm32_fmc2_nfc *)chip->priv;
+ struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
+ struct stm32_fmc2_timings *tims = &nand->timings;
+ unsigned long hclk = clk_get_rate(nfc->clk);
+ unsigned long hclkp = NSEC_PER_SEC / (hclk / 1000);
+ unsigned long timing, tar, tclr, thiz, twait;
+ unsigned long tset_mem, tset_att, thold_mem, thold_att;
+
+ tar = max_t(unsigned long, hclkp, sdrt->tAR_min);
+ timing = DIV_ROUND_UP(tar, hclkp) - 1;
+ tims->tar = min_t(unsigned long, timing, FMC2_PCR_TIMING_MASK);
+
+ tclr = max_t(unsigned long, hclkp, sdrt->tCLR_min);
+ timing = DIV_ROUND_UP(tclr, hclkp) - 1;
+ tims->tclr = min_t(unsigned long, timing, FMC2_PCR_TIMING_MASK);
+
+ tims->thiz = FMC2_THIZ;
+ thiz = (tims->thiz + 1) * hclkp;
+
+ /*
+ * tWAIT > tRP
+ * tWAIT > tWP
+ * tWAIT > tREA + tIO
+ */
+ twait = max_t(unsigned long, hclkp, sdrt->tRP_min);
+ twait = max_t(unsigned long, twait, sdrt->tWP_min);
+ twait = max_t(unsigned long, twait, sdrt->tREA_max + FMC2_TIO);
+ timing = DIV_ROUND_UP(twait, hclkp);
+ tims->twait = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
+
+ /*
+ * tSETUP_MEM > tCS - tWAIT
+ * tSETUP_MEM > tALS - tWAIT
+ * tSETUP_MEM > tDS - (tWAIT - tHIZ)
+ */
+ tset_mem = hclkp;
+ if (sdrt->tCS_min > twait && (tset_mem < sdrt->tCS_min - twait))
+ tset_mem = sdrt->tCS_min - twait;
+ if (sdrt->tALS_min > twait && (tset_mem < sdrt->tALS_min - twait))
+ tset_mem = sdrt->tALS_min - twait;
+ if (twait > thiz && (sdrt->tDS_min > twait - thiz) &&
+ (tset_mem < sdrt->tDS_min - (twait - thiz)))
+ tset_mem = sdrt->tDS_min - (twait - thiz);
+ timing = DIV_ROUND_UP(tset_mem, hclkp);
+ tims->tset_mem = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
+
+ /*
+ * tHOLD_MEM > tCH
+ * tHOLD_MEM > tREH - tSETUP_MEM
+ * tHOLD_MEM > max(tRC, tWC) - (tSETUP_MEM + tWAIT)
+ */
+ thold_mem = max_t(unsigned long, hclkp, sdrt->tCH_min);
+ if (sdrt->tREH_min > tset_mem &&
+ (thold_mem < sdrt->tREH_min - tset_mem))
+ thold_mem = sdrt->tREH_min - tset_mem;
+ if ((sdrt->tRC_min > tset_mem + twait) &&
+ (thold_mem < sdrt->tRC_min - (tset_mem + twait)))
+ thold_mem = sdrt->tRC_min - (tset_mem + twait);
+ if ((sdrt->tWC_min > tset_mem + twait) &&
+ (thold_mem < sdrt->tWC_min - (tset_mem + twait)))
+ thold_mem = sdrt->tWC_min - (tset_mem + twait);
+ timing = DIV_ROUND_UP(thold_mem, hclkp);
+ tims->thold_mem = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
+
+ /*
+ * tSETUP_ATT > tCS - tWAIT
+ * tSETUP_ATT > tCLS - tWAIT
+ * tSETUP_ATT > tALS - tWAIT
+ * tSETUP_ATT > tRHW - tHOLD_MEM
+ * tSETUP_ATT > tDS - (tWAIT - tHIZ)
+ */
+ tset_att = hclkp;
+ if (sdrt->tCS_min > twait && (tset_att < sdrt->tCS_min - twait))
+ tset_att = sdrt->tCS_min - twait;
+ if (sdrt->tCLS_min > twait && (tset_att < sdrt->tCLS_min - twait))
+ tset_att = sdrt->tCLS_min - twait;
+ if (sdrt->tALS_min > twait && (tset_att < sdrt->tALS_min - twait))
+ tset_att = sdrt->tALS_min - twait;
+ if (sdrt->tRHW_min > thold_mem &&
+ (tset_att < sdrt->tRHW_min - thold_mem))
+ tset_att = sdrt->tRHW_min - thold_mem;
+ if (twait > thiz && (sdrt->tDS_min > twait - thiz) &&
+ (tset_att < sdrt->tDS_min - (twait - thiz)))
+ tset_att = sdrt->tDS_min - (twait - thiz);
+ timing = DIV_ROUND_UP(tset_att, hclkp);
+ tims->tset_att = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
+
+ /*
+ * tHOLD_ATT > tALH
+ * tHOLD_ATT > tCH
+ * tHOLD_ATT > tCLH
+ * tHOLD_ATT > tCOH
+ * tHOLD_ATT > tDH
+ * tHOLD_ATT > tWB + tIO + tSYNC - tSETUP_MEM
+ * tHOLD_ATT > tADL - tSETUP_MEM
+ * tHOLD_ATT > tWH - tSETUP_MEM
+ * tHOLD_ATT > tWHR - tSETUP_MEM
+ * tHOLD_ATT > tRC - (tSETUP_ATT + tWAIT)
+ * tHOLD_ATT > tWC - (tSETUP_ATT + tWAIT)
+ */
+ thold_att = max_t(unsigned long, hclkp, sdrt->tALH_min);
+ thold_att = max_t(unsigned long, thold_att, sdrt->tCH_min);
+ thold_att = max_t(unsigned long, thold_att, sdrt->tCLH_min);
+ thold_att = max_t(unsigned long, thold_att, sdrt->tCOH_min);
+ thold_att = max_t(unsigned long, thold_att, sdrt->tDH_min);
+ if ((sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC > tset_mem) &&
+ (thold_att < sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC - tset_mem))
+ thold_att = sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC - tset_mem;
+ if (sdrt->tADL_min > tset_mem &&
+ (thold_att < sdrt->tADL_min - tset_mem))
+ thold_att = sdrt->tADL_min - tset_mem;
+ if (sdrt->tWH_min > tset_mem &&
+ (thold_att < sdrt->tWH_min - tset_mem))
+ thold_att = sdrt->tWH_min - tset_mem;
+ if (sdrt->tWHR_min > tset_mem &&
+ (thold_att < sdrt->tWHR_min - tset_mem))
+ thold_att = sdrt->tWHR_min - tset_mem;
+ if ((sdrt->tRC_min > tset_att + twait) &&
+ (thold_att < sdrt->tRC_min - (tset_att + twait)))
+ thold_att = sdrt->tRC_min - (tset_att + twait);
+ if ((sdrt->tWC_min > tset_att + twait) &&
+ (thold_att < sdrt->tWC_min - (tset_att + twait)))
+ thold_att = sdrt->tWC_min - (tset_att + twait);
+ timing = DIV_ROUND_UP(thold_att, hclkp);
+ tims->thold_att = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
+}
+
+static int stm32_fmc2_nfc_setup_interface(struct nand_chip *chip, int chipnr,
+ const struct nand_interface_config *cf)
+{
+ const struct nand_sdr_timings *sdrt;
+
+ sdrt = nand_get_sdr_timings(cf);
+ if (IS_ERR(sdrt))
+ return PTR_ERR(sdrt);
+
+ if (sdrt->tRC_min < 30000)
+ return -EOPNOTSUPP;
+
+ if (chipnr == NAND_DATA_IFACE_CHECK_ONLY)
+ return 0;
+
+ stm32_fmc2_nfc_calc_timings(chip, sdrt);
+ stm32_fmc2_nfc_timings_init(chip);
+
+ return 0;
+}
+
+static void stm32_fmc2_nfc_nand_callbacks_setup(struct nand_chip *chip)
+{
+ chip->ecc.hwctl = stm32_fmc2_nfc_hwctl;
+
+ /*
+ * Specific callbacks to read/write a page depending on
+ * the algo used (Hamming, BCH).
+ */
+ if (chip->ecc.strength == FMC2_ECC_HAM) {
+ /* Hamming is used */
+ chip->ecc.calculate = stm32_fmc2_nfc_ham_calculate;
+ chip->ecc.correct = stm32_fmc2_nfc_ham_correct;
+ chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 4 : 3;
+ chip->ecc.options |= NAND_ECC_GENERIC_ERASED_CHECK;
+ return;
+ }
+
+ /* BCH is used */
+ chip->ecc.read_page = stm32_fmc2_nfc_read_page;
+ chip->ecc.calculate = stm32_fmc2_nfc_bch_calculate;
+ chip->ecc.correct = stm32_fmc2_nfc_bch_correct;
+
+ if (chip->ecc.strength == FMC2_ECC_BCH8)
+ chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 14 : 13;
+ else
+ chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 8 : 7;
+}
+
+static int stm32_fmc2_nfc_calc_ecc_bytes(int step_size, int strength)
+{
+ /* Hamming */
+ if (strength == FMC2_ECC_HAM)
+ return 4;
+
+ /* BCH8 */
+ if (strength == FMC2_ECC_BCH8)
+ return 14;
+
+ /* BCH4 */
+ return 8;
+}
+
+NAND_ECC_CAPS_SINGLE(stm32_fmc2_nfc_ecc_caps, stm32_fmc2_nfc_calc_ecc_bytes,
+ FMC2_ECC_STEP_SIZE,
+ FMC2_ECC_HAM, FMC2_ECC_BCH4, FMC2_ECC_BCH8);
+
+static int stm32_fmc2_nfc_parse_child(struct stm32_fmc2_nfc *nfc,
+ struct device_node *node)
+{
+ struct stm32_fmc2_nand *nand = &nfc->nand;
+ u32 cs[FMC2_MAX_CE];
+ enum of_gpio_flags flags;
+ int ret, i;
+
+ if (!of_get_property(node, "reg", &nand->ncs))
+ return -EINVAL;
+
+ nand->ncs /= sizeof(u32);
+ if (!nand->ncs) {
+ pr_err("Invalid reg property size\n");
+ return -EINVAL;
+ }
+
+ ret = of_property_read_u32_array(node, "reg", cs, nand->ncs);
+ if (ret < 0) {
+ pr_err("Could not retrieve reg property\n");
+ return -EINVAL;
+ }
+
+ for (i = 0; i < nand->ncs; i++) {
+ if (cs[i] >= FMC2_MAX_CE) {
+ pr_err("Invalid reg value: %d\n", nand->cs_used[i]);
+ return -EINVAL;
+ }
+
+ if (nfc->cs_assigned & BIT(cs[i])) {
+ pr_err("Cs already assigned: %d\n", nand->cs_used[i]);
+ return -EINVAL;
+ }
+
+ nfc->cs_assigned |= BIT(cs[i]);
+ nand->cs_used[i] = cs[i];
+ }
+
+ nand->wp_gpio = of_get_named_gpio_flags(node, "wp-gpios", 0, &flags);
+ if (gpio_is_valid(nand->wp_gpio)) {
+ gpio_request(nand->wp_gpio, "nand-wp");
+ gpio_direction_output(nand->wp_gpio, !(flags & OF_GPIO_ACTIVE_LOW));
+ }
+
+ return 0;
+}
+
+static int stm32_fmc2_nfc_parse_dt(struct device *dev,
+ struct stm32_fmc2_nfc *nfc)
+{
+ struct device_node *child;
+ int ret, nchips = 0;
+
+ for_each_available_child_of_node(dev->of_node, child)
+ nchips++;
+
+ if (!nchips) {
+ dev_err(dev, "NAND chip not defined\n");
+ return -EINVAL;
+ }
+
+ if (nchips > 1) {
+ dev_err(dev, "Too many NAND chips defined\n");
+ return -EINVAL;
+ }
+
+ for_each_available_child_of_node(dev->of_node, child) {
+ ret = stm32_fmc2_nfc_parse_child(nfc, child);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static struct device *stm32_fmc2_nfc_get_cdev(struct device *dev)
+{
+ struct device *pdev = dev->parent;
+ bool ebi_found = false;
+
+ if (pdev && of_device_is_compatible(pdev->of_node,
+ "st,stm32mp1-fmc2-ebi"))
+ ebi_found = true;
+
+ if (of_device_is_compatible(dev->of_node, "st,stm32mp1-fmc2-nfc")) {
+ if (ebi_found)
+ return pdev;
+
+ return NULL;
+ }
+
+ if (!ebi_found)
+ return dev;
+
+ return NULL;
+}
+
+static const struct nand_controller_ops stm32_fmc2_nfc_controller_ops = {
+ .setup_interface = stm32_fmc2_nfc_setup_interface,
+};
+
+static int __init stm32_fmc2_nfc_probe(struct device *dev)
+{
+ struct stm32_fmc2_nfc *nfc;
+ struct nand_ecclayout *ecclayout;
+ struct device *cdev;
+ int oob_index, chip_cs, mem_region, ret;
+ unsigned int i;
+ int start_region = 0;
+ struct mtd_info *mtd;
+ struct nand_chip *nand;
+
+ cdev = stm32_fmc2_nfc_get_cdev(dev);
+ if (!cdev)
+ return -EINVAL;
+
+ nfc = kzalloc(sizeof(*nfc), GFP_KERNEL);
+ if (!nfc)
+ return -ENOMEM;
+
+ ret = stm32_fmc2_nfc_parse_dt(dev, nfc);
+ if (ret)
+ goto out_kfree;
+
+ nfc->clk = clk_get(cdev, NULL);
+ if (IS_ERR(nfc->clk)) {
+ ret = PTR_ERR(nfc->clk);
+ goto out_kfree;
+ }
+
+ clk_enable(nfc->clk);
+
+ nfc->io_base = of_iomap(cdev->of_node, 0);
+ if (!nfc->io_base) {
+ ret = -ENOMEM;
+ goto out_clk;
+ }
+
+ ret = device_reset_us(dev, 2);
+ if (ret)
+ goto out_clk;
+
+ if (dev == cdev)
+ start_region = 1;
+
+ for (chip_cs = 0, mem_region = start_region; chip_cs < FMC2_MAX_CE;
+ chip_cs++, mem_region += 3) {
+ if (!(nfc->cs_assigned & BIT(chip_cs)))
+ continue;
+
+ nfc->data_base[chip_cs] = of_iomap(dev->of_node, mem_region);
+ if (!nfc->data_base[chip_cs]) {
+ dev_err(dev, "Resource data_base not found for cs%d", chip_cs);
+ return ret;
+ }
+
+ nfc->cmd_base[chip_cs] = of_iomap(dev->of_node, mem_region + 1);
+ if (!nfc->cmd_base[chip_cs]) {
+ dev_err(dev, "Resource cmd_base not found for cs%d", chip_cs);
+ return ret;
+ }
+
+ nfc->addr_base[chip_cs] = of_iomap(dev->of_node, mem_region + 2);
+ if (!nfc->addr_base[chip_cs]) {
+ dev_err(dev, "Resource addr_base not found for cs%d", chip_cs);
+ return ret;
+ }
+ }
+
+ stm32_fmc2_nfc_init(nfc, dev != cdev);
+
+ nand = &nfc->nand.chip;
+ mtd = nand_to_mtd(nand);
+ nand->priv = nfc;
+ mtd->dev.parent = dev;
+
+ nand_controller_init(&nand->legacy.dummy_controller);
+ nand->legacy.dummy_controller.ops = &stm32_fmc2_nfc_controller_ops;
+
+ nand->legacy.select_chip = stm32_fmc2_nfc_select_chip;
+ nand->legacy.cmd_ctrl = stm32_fmc2_nfc_cmd_ctrl;
+ nand->legacy.chip_delay = FMC2_RB_DELAY_US;
+ nand->options |= NAND_BUSWIDTH_AUTO | NAND_NO_SUBPAGE_WRITE;
+
+ /* Default ECC settings */
+ nand->ecc.mode = NAND_ECC_HW;
+ nand->ecc.size = FMC2_ECC_STEP_SIZE;
+ nand->ecc.strength = FMC2_ECC_BCH8;
+
+ /* Disable Write Protect */
+ if (gpio_is_valid(nfc->nand.wp_gpio))
+ gpio_set_value(nfc->nand.wp_gpio, 0);
+
+ ret = nand_scan_ident(nand, nfc->nand.ncs, NULL);
+ if (ret)
+ return ret;
+
+ /*
+ * Only NAND_ECC_HW mode is actually supported
+ * Hamming => ecc.strength = 1
+ * BCH4 => ecc.strength = 4
+ * BCH8 => ecc.strength = 8
+ * ECC sector size = 512
+ */
+ if (nand->ecc.mode != NAND_ECC_HW) {
+ dev_err(dev, "Nand_ecc_mode is not well defined in the DT\n");
+ return -EINVAL;
+ }
+
+ ret = nand_ecc_choose_conf(nand, &stm32_fmc2_nfc_ecc_caps,
+ mtd->oobsize - FMC2_BBM_LEN);
+ if (ret) {
+ dev_err(dev, "No valid ECC settings set\n");
+ return ret;
+ }
+
+ if (nand->bbt_options & NAND_BBT_USE_FLASH)
+ nand->bbt_options |= NAND_BBT_NO_OOB;
+
+ stm32_fmc2_nfc_nand_callbacks_setup(nand);
+
+ /* Define ECC layout */
+ ecclayout = &nfc->ecclayout;
+ ecclayout->eccbytes = nand->ecc.bytes *
+ (mtd->writesize / nand->ecc.size);
+ oob_index = FMC2_BBM_LEN;
+ for (i = 0; i < ecclayout->eccbytes; i++, oob_index++)
+ ecclayout->eccpos[i] = oob_index;
+ ecclayout->oobfree->offset = oob_index;
+ ecclayout->oobfree->length = mtd->oobsize - ecclayout->oobfree->offset;
+ mtd_set_ecclayout(mtd, ecclayout);
+
+ stm32_fmc2_nfc_set_buswidth_16(nfc, nand->options & NAND_BUSWIDTH_16);
+
+ ret = nand_scan_tail(nand);
+ if (ret)
+ return ret;
+
+ return add_mtd_nand_device(mtd, "nand");
+
+out_clk:
+ clk_disable(nfc->clk);
+
+out_kfree:
+ kfree(nfc);
+
+ return ret;
+}
+
+static __maybe_unused struct of_device_id stm32_nand_dt_ids[] = {
+ { .compatible = "st,stm32mp15-fmc2", },
+ { .compatible = "st,stm32mp1-fmc2-nfc", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, stm32_nand_dt_ids);
+
+static struct driver stm32_nand_driver = {
+ .name = "stm32_fmc2_nfc",
+ .probe = stm32_fmc2_nfc_probe,
+ .of_compatible = DRV_OF_COMPAT(stm32_nand_dt_ids),
+};
+coredevice_platform_driver(stm32_nand_driver);
--
2.39.1
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