[PATCH v3 4/6] mtd: rawnand: add NVIDIA Tegra NAND Flash controller driver

From: Stefan Agner
Date: Thu May 31 2018 - 18:17:17 EST

Add support for the NAND flash controller found on NVIDIA
Tegra 2 SoCs. This implementation does not make use of the
command queue feature. Regular operations/data transfers are
done in PIO mode. Page read/writes with hardware ECC make
use of the DMA for data transfer.

Signed-off-by: Lucas Stach <dev@xxxxxxxxxx>
Signed-off-by: Stefan Agner <stefan@xxxxxxxx>
---
MAINTAINERS | 7 +
drivers/mtd/nand/raw/Kconfig | 6 +
drivers/mtd/nand/raw/Makefile | 1 +
drivers/mtd/nand/raw/tegra_nand.c | 1143 +++++++++++++++++++++++++++++
4 files changed, 1157 insertions(+)
create mode 100644 drivers/mtd/nand/raw/tegra_nand.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 58b9861ccf99..c2e5571c85d4 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -13844,6 +13844,13 @@ M: Laxman Dewangan <ldewangan@xxxxxxxxxx>
S: Supported
F: drivers/input/keyboard/tegra-kbc.c

+TEGRA NAND DRIVER
+M: Stefan Agner <stefan@xxxxxxxx>
+M: Lucas Stach <dev@xxxxxxxxxx>
+S: Maintained
+F: Documentation/devicetree/bindings/mtd/nvidia-tegra20-nand.txt
+F: drivers/mtd/nand/raw/tegra_nand.c
+
TEGRA PWM DRIVER
M: Thierry Reding <thierry.reding@xxxxxxxxx>
S: Supported
diff --git a/drivers/mtd/nand/raw/Kconfig b/drivers/mtd/nand/raw/Kconfig
index 19a2b283fbbe..e9093f52371e 100644
--- a/drivers/mtd/nand/raw/Kconfig
+++ b/drivers/mtd/nand/raw/Kconfig
@@ -534,4 +534,10 @@ config MTD_NAND_MTK
Enables support for NAND controller on MTK SoCs.
This controller is found on mt27xx, mt81xx, mt65xx SoCs.

+config MTD_NAND_TEGRA
+ tristate "Support for NAND controller on NVIDIA Tegra"
+ depends on ARCH_TEGRA || COMPILE_TEST
+ help
+ Enables support for NAND flash controller on NVIDIA Tegra SoC.
+
endif # MTD_NAND
diff --git a/drivers/mtd/nand/raw/Makefile b/drivers/mtd/nand/raw/Makefile
index 165b7ef9e9a1..d5a5f9832b88 100644
--- a/drivers/mtd/nand/raw/Makefile
+++ b/drivers/mtd/nand/raw/Makefile
@@ -56,6 +56,7 @@ obj-$(CONFIG_MTD_NAND_HISI504) += hisi504_nand.o
obj-$(CONFIG_MTD_NAND_BRCMNAND) += brcmnand/
obj-$(CONFIG_MTD_NAND_QCOM) += qcom_nandc.o
obj-$(CONFIG_MTD_NAND_MTK) += mtk_ecc.o mtk_nand.o
+obj-$(CONFIG_MTD_NAND_TEGRA) += tegra_nand.o

nand-objs := nand_base.o nand_bbt.o nand_timings.o nand_ids.o
nand-objs += nand_amd.o
diff --git a/drivers/mtd/nand/raw/tegra_nand.c b/drivers/mtd/nand/raw/tegra_nand.c
new file mode 100644
index 000000000000..e9664f2938a3
--- /dev/null
+++ b/drivers/mtd/nand/raw/tegra_nand.c
@@ -0,0 +1,1143 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 Stefan Agner <stefan@xxxxxxxx>
+ * Copyright (C) 2014-2015 Lucas Stach <dev@xxxxxxxxxx>
+ * Copyright (C) 2012 Avionic Design GmbH
+ */
+
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/rawnand.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+
+#define CMD 0x00
+#define CMD_GO BIT(31)
+#define CMD_CLE BIT(30)
+#define CMD_ALE BIT(29)
+#define CMD_PIO BIT(28)
+#define CMD_TX BIT(27)
+#define CMD_RX BIT(26)
+#define CMD_SEC_CMD BIT(25)
+#define CMD_AFT_DAT BIT(24)
+#define CMD_TRANS_SIZE(x) (((x - 1) & 0xf) << 20)
+#define CMD_A_VALID BIT(19)
+#define CMD_B_VALID BIT(18)
+#define CMD_RD_STATUS_CHK BIT(17)
+#define CMD_RBSY_CHK BIT(16)
+#define CMD_CE(x) BIT((8 + ((x) & 0x7)))
+#define CMD_CLE_SIZE(x) (((x - 1) & 0x3) << 4)
+#define CMD_ALE_SIZE(x) (((x - 1) & 0xf) << 0)
+
+#define STATUS 0x04
+
+#define ISR 0x08
+#define ISR_CORRFAIL_ERR BIT(24)
+#define ISR_UND BIT(7)
+#define ISR_OVR BIT(6)
+#define ISR_CMD_DONE BIT(5)
+#define ISR_ECC_ERR BIT(4)
+
+#define IER 0x0c
+#define IER_ERR_TRIG_VAL(x) (((x) & 0xf) << 16)
+#define IER_UND BIT(7)
+#define IER_OVR BIT(6)
+#define IER_CMD_DONE BIT(5)
+#define IER_ECC_ERR BIT(4)
+#define IER_GIE BIT(0)
+
+#define CFG 0x10
+#define CFG_HW_ECC BIT(31)
+#define CFG_ECC_SEL BIT(30)
+#define CFG_ERR_COR BIT(29)
+#define CFG_PIPE_EN BIT(28)
+#define CFG_TVAL_4 (0 << 24)
+#define CFG_TVAL_6 (1 << 24)
+#define CFG_TVAL_8 (2 << 24)
+#define CFG_SKIP_SPARE BIT(23)
+#define CFG_BUS_WIDTH_16 BIT(21)
+#define CFG_COM_BSY BIT(20)
+#define CFG_PS_256 (0 << 16)
+#define CFG_PS_512 (1 << 16)
+#define CFG_PS_1024 (2 << 16)
+#define CFG_PS_2048 (3 << 16)
+#define CFG_PS_4096 (4 << 16)
+#define CFG_SKIP_SPARE_SIZE_4 (0 << 14)
+#define CFG_SKIP_SPARE_SIZE_8 (1 << 14)
+#define CFG_SKIP_SPARE_SIZE_12 (2 << 14)
+#define CFG_SKIP_SPARE_SIZE_16 (3 << 14)
+#define CFG_TAG_BYTE_SIZE(x) ((x) & 0xff)
+
+#define TIMING_1 0x14
+#define TIMING_TRP_RESP(x) (((x) & 0xf) << 28)
+#define TIMING_TWB(x) (((x) & 0xf) << 24)
+#define TIMING_TCR_TAR_TRR(x) (((x) & 0xf) << 20)
+#define TIMING_TWHR(x) (((x) & 0xf) << 16)
+#define TIMING_TCS(x) (((x) & 0x3) << 14)
+#define TIMING_TWH(x) (((x) & 0x3) << 12)
+#define TIMING_TWP(x) (((x) & 0xf) << 8)
+#define TIMING_TRH(x) (((x) & 0x3) << 4)
+#define TIMING_TRP(x) (((x) & 0xf) << 0)
+
+#define RESP 0x18
+
+#define TIMING_2 0x1c
+#define TIMING_TADL(x) ((x) & 0xf)
+
+#define CMD_1 0x20
+#define CMD_2 0x24
+#define ADDR_1 0x28
+#define ADDR_2 0x2c
+
+#define DMA_CTRL 0x30
+#define DMA_CTRL_GO BIT(31)
+#define DMA_CTRL_IN (0 << 30)
+#define DMA_CTRL_OUT BIT(30)
+#define DMA_CTRL_PERF_EN BIT(29)
+#define DMA_CTRL_IE_DONE BIT(28)
+#define DMA_CTRL_REUSE BIT(27)
+#define DMA_CTRL_BURST_1 (2 << 24)
+#define DMA_CTRL_BURST_4 (3 << 24)
+#define DMA_CTRL_BURST_8 (4 << 24)
+#define DMA_CTRL_BURST_16 (5 << 24)
+#define DMA_CTRL_IS_DONE BIT(20)
+#define DMA_CTRL_EN_A BIT(2)
+#define DMA_CTRL_EN_B BIT(1)
+
+#define DMA_CFG_A 0x34
+#define DMA_CFG_B 0x38
+
+#define FIFO_CTRL 0x3c
+#define FIFO_CTRL_CLR_ALL BIT(3)
+
+#define DATA_PTR 0x40
+#define TAG_PTR 0x44
+#define ECC_PTR 0x48
+
+#define DEC_STATUS 0x4c
+#define DEC_STATUS_A_ECC_FAIL BIT(1)
+#define DEC_STATUS_ERR_COUNT_MASK 0x00ff0000
+#define DEC_STATUS_ERR_COUNT_SHIFT 16
+
+#define HWSTATUS_CMD 0x50
+#define HWSTATUS_MASK 0x54
+#define HWSTATUS_RDSTATUS_MASK(x) (((x) & 0xff) << 24)
+#define HWSTATUS_RDSTATUS_VALUE(x) (((x) & 0xff) << 16)
+#define HWSTATUS_RBSY_MASK(x) (((x) & 0xff) << 8)
+#define HWSTATUS_RBSY_VALUE(x) (((x) & 0xff) << 0)
+
+#define BCH_CONFIG 0xcc
+#define BCH_ENABLE BIT(0)
+#define BCH_TVAL_4 (0 << 4)
+#define BCH_TVAL_8 (1 << 4)
+#define BCH_TVAL_14 (2 << 4)
+#define BCH_TVAL_16 (3 << 4)
+
+#define DEC_STAT_RESULT 0xd0
+#define DEC_STAT_BUF 0xd4
+#define DEC_STAT_BUF_FAIL_SEC_FLAG_MASK 0xff000000
+#define DEC_STAT_BUF_FAIL_SEC_FLAG_SHIFT 24
+#define DEC_STAT_BUF_CORR_SEC_FLAG_MASK 0x00ff0000
+#define DEC_STAT_BUF_CORR_SEC_FLAG_SHIFT 16
+#define DEC_STAT_BUF_MAX_CORR_CNT_MASK 0x00001f00
+#define DEC_STAT_BUF_MAX_CORR_CNT_SHIFT 8
+
+#define OFFSET(val, off) ((val) < (off) ? 0 : (val) - (off))
+
+#define SKIP_SPARE_BYTES 4
+#define BITS_PER_STEP_RS 18
+#define BITS_PER_STEP_BCH 13
+
+struct tegra_nand_controller {
+ struct nand_hw_control controller;
+ void __iomem *regs;
+ struct clk *clk;
+ struct device *dev;
+ struct completion command_complete;
+ struct completion dma_complete;
+ bool last_read_error;
+ int cur_chip;
+ struct nand_chip *chip;
+};
+
+struct tegra_nand_chip {
+ struct nand_chip chip;
+ struct gpio_desc *wp_gpio;
+ struct mtd_oob_region tag;
+};
+
+static inline struct tegra_nand_controller *to_tegra_ctrl(
+ struct nand_hw_control *hw_ctrl)
+{
+ return container_of(hw_ctrl, struct tegra_nand_controller, controller);
+}
+
+static inline struct tegra_nand_chip *to_tegra_chip(struct nand_chip *chip)
+{
+ return container_of(chip, struct tegra_nand_chip, chip);
+}
+
+static int tegra_nand_ooblayout_rs_ecc(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ int bytes_per_step = DIV_ROUND_UP(BITS_PER_STEP_RS * chip->ecc.strength,
+ BITS_PER_BYTE);
+
+ if (section > 0)
+ return -ERANGE;
+
+ oobregion->offset = SKIP_SPARE_BYTES;
+ oobregion->length = round_up(bytes_per_step * chip->ecc.steps, 4);
+
+ return 0;
+}
+
+static int tegra_nand_ooblayout_rs_free(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ int bytes_per_step = DIV_ROUND_UP(BITS_PER_STEP_RS * chip->ecc.strength,
+ BITS_PER_BYTE);
+
+ if (section > 0)
+ return -ERANGE;
+
+ oobregion->offset = SKIP_SPARE_BYTES +
+ round_up(bytes_per_step * chip->ecc.steps, 4);
+ oobregion->length = mtd->oobsize - oobregion->offset;
+
+ return 0;
+}
+
+static const struct mtd_ooblayout_ops tegra_nand_oob_rs_ops = {
+ .ecc = tegra_nand_ooblayout_rs_ecc,
+ .free = tegra_nand_ooblayout_rs_free,
+};
+
+static int tegra_nand_ooblayout_bch_ecc(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ int bytes_per_step = DIV_ROUND_UP(BITS_PER_STEP_BCH * chip->ecc.strength,
+ BITS_PER_BYTE);
+
+ if (section > 0)
+ return -ERANGE;
+
+ oobregion->offset = SKIP_SPARE_BYTES;
+ oobregion->length = round_up(bytes_per_step * chip->ecc.steps, 4);
+
+ return 0;
+}
+
+static int tegra_nand_ooblayout_bch_free(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ int bytes_per_step = DIV_ROUND_UP(BITS_PER_STEP_BCH * chip->ecc.strength,
+ BITS_PER_BYTE);
+
+ if (section > 0)
+ return -ERANGE;
+
+ oobregion->offset = SKIP_SPARE_BYTES +
+ round_up(bytes_per_step * chip->ecc.steps, 4);
+ oobregion->length = mtd->oobsize - oobregion->offset;
+
+ return 0;
+}
+
+/*
+ * Layout with tag bytes is
+ *
+ * --------------------------------------------------------------------------
+ * | main area | skip bytes | tag bytes | parity | .. |
+ * --------------------------------------------------------------------------
+ *
+ * If not tag bytes are written, parity moves right after skip bytes!
+ */
+static const struct mtd_ooblayout_ops tegra_nand_oob_bch_ops = {
+ .ecc = tegra_nand_ooblayout_bch_ecc,
+ .free = tegra_nand_ooblayout_bch_free,
+};
+
+static irqreturn_t tegra_nand_irq(int irq, void *data)
+{
+ struct tegra_nand_controller *ctrl = data;
+ u32 isr, dma;
+
+ isr = readl_relaxed(ctrl->regs + ISR);
+ dma = readl_relaxed(ctrl->regs + DMA_CTRL);
+ dev_dbg(ctrl->dev, "isr %08x\n", isr);
+
+ if (!isr && !(dma & DMA_CTRL_IS_DONE))
+ return IRQ_NONE;
+
+ /*
+ * The bit name is somewhat missleading: This is also set when
+ * HW ECC was successful. The data sheet states:
+ * Correctable OR Un-correctable errors occurred in the DMA transfer...
+ */
+ if (isr & ISR_CORRFAIL_ERR)
+ ctrl->last_read_error = true;
+
+ if (isr & ISR_CMD_DONE)
+ complete(&ctrl->command_complete);
+
+ if (isr & ISR_UND)
+ dev_err(ctrl->dev, "FIFO underrun\n");
+
+ if (isr & ISR_OVR)
+ dev_err(ctrl->dev, "FIFO overrun\n");
+
+ /* handle DMA interrupts */
+ if (dma & DMA_CTRL_IS_DONE) {
+ writel_relaxed(dma, ctrl->regs + DMA_CTRL);
+ complete(&ctrl->dma_complete);
+ }
+
+ /* clear interrupts */
+ writel_relaxed(isr, ctrl->regs + ISR);
+
+ return IRQ_HANDLED;
+}
+
+static const char * const tegra_nand_reg_names[] = {
+ "COMMAND",
+ "STATUS",
+ "ISR",
+ "IER",
+ "CONFIG",
+ "TIMING",
+ NULL,
+ "TIMING2",
+ "CMD_REG1",
+ "CMD_REG2",
+ "ADDR_REG1",
+ "ADDR_REG2",
+ "DMA_MST_CTRL",
+ "DMA_CFG_A",
+ "DMA_CFG_B",
+ "FIFO_CTRL",
+};
+
+static void tegra_nand_dump_reg(struct tegra_nand_controller *ctrl)
+{
+ u32 reg;
+ int i;
+
+ dev_err(ctrl->dev, "Tegra NAND controller register dump\n");
+ for (i = 0; i < ARRAY_SIZE(tegra_nand_reg_names); i++) {
+ const char *reg_name = tegra_nand_reg_names[i];
+
+ if (!reg_name)
+ continue;
+
+ reg = readl_relaxed(ctrl->regs + (i * 4));
+ dev_err(ctrl->dev, "%s: 0x%08x\n", reg_name, reg);
+ }
+}
+
+static int tegra_nand_cmd(struct nand_chip *chip,
+ const struct nand_subop *subop)
+{
+ const struct nand_op_instr *instr;
+ const struct nand_op_instr *instr_data_in = NULL;
+ struct tegra_nand_controller *ctrl = to_tegra_ctrl(chip->controller);
+ unsigned int op_id, size = 0, offset = 0;
+ bool first_cmd = true;
+ u32 reg, cmd = 0;
+ int ret;
+
+ for (op_id = 0; op_id < subop->ninstrs; op_id++) {
+ unsigned int naddrs, i;
+ const u8 *addrs;
+ u32 addr1 = 0, addr2 = 0;
+
+ instr = &subop->instrs[op_id];
+
+ switch (instr->type) {
+ case NAND_OP_CMD_INSTR:
+ if (first_cmd) {
+ cmd |= CMD_CLE;
+ writel_relaxed(instr->ctx.cmd.opcode,
+ ctrl->regs + CMD_1);
+ } else {
+ cmd |= CMD_SEC_CMD;
+ writel_relaxed(instr->ctx.cmd.opcode,
+ ctrl->regs + CMD_2);
+ }
+ first_cmd = false;
+ break;
+ case NAND_OP_ADDR_INSTR:
+ offset = nand_subop_get_addr_start_off(subop, op_id);
+ naddrs = nand_subop_get_num_addr_cyc(subop, op_id);
+ addrs = &instr->ctx.addr.addrs[offset];
+
+ cmd |= CMD_ALE | CMD_ALE_SIZE(naddrs);
+ for (i = 0; i < min_t(unsigned int, 4, naddrs); i++)
+ addr1 |= *addrs++ << (BITS_PER_BYTE * i);
+ naddrs -= i;
+ for (i = 0; i < min_t(unsigned int, 4, naddrs); i++)
+ addr2 |= *addrs++ << (BITS_PER_BYTE * i);
+ writel_relaxed(addr1, ctrl->regs + ADDR_1);
+ writel_relaxed(addr2, ctrl->regs + ADDR_2);
+ break;
+
+ case NAND_OP_DATA_IN_INSTR:
+ size = nand_subop_get_data_len(subop, op_id);
+ offset = nand_subop_get_data_start_off(subop, op_id);
+
+ cmd |= CMD_TRANS_SIZE(size) | CMD_PIO | CMD_RX |
+ CMD_A_VALID;
+
+ instr_data_in = instr;
+ break;
+
+ case NAND_OP_DATA_OUT_INSTR:
+ size = nand_subop_get_data_len(subop, op_id);
+ offset = nand_subop_get_data_start_off(subop, op_id);
+
+ cmd |= CMD_TRANS_SIZE(size) | CMD_PIO | CMD_TX |
+ CMD_A_VALID;
+
+ memcpy(&reg, instr->ctx.data.buf.out + offset, size);
+ writel_relaxed(reg, ctrl->regs + RESP);
+
+ break;
+ case NAND_OP_WAITRDY_INSTR:
+ cmd |= CMD_RBSY_CHK;
+ break;
+
+ }
+ }
+
+ cmd |= CMD_GO | CMD_CE(ctrl->cur_chip);
+ writel_relaxed(cmd, ctrl->regs + CMD);
+ ret = wait_for_completion_timeout(&ctrl->command_complete,
+ msecs_to_jiffies(500));
+ if (!ret) {
+ dev_err(ctrl->dev, "CMD timeout\n");
+ tegra_nand_dump_reg(ctrl);
+ return -ETIMEDOUT;
+ }
+
+ if (instr_data_in) {
+ reg = readl_relaxed(ctrl->regs + RESP);
+ memcpy(instr_data_in->ctx.data.buf.in + offset, &reg, size);
+ }
+
+ return 0;
+}
+
+static const struct nand_op_parser tegra_nand_op_parser = NAND_OP_PARSER(
+ NAND_OP_PARSER_PATTERN(tegra_nand_cmd,
+ NAND_OP_PARSER_PAT_CMD_ELEM(true),
+ NAND_OP_PARSER_PAT_ADDR_ELEM(true, 8),
+ NAND_OP_PARSER_PAT_CMD_ELEM(true),
+ NAND_OP_PARSER_PAT_WAITRDY_ELEM(true)),
+ NAND_OP_PARSER_PATTERN(tegra_nand_cmd,
+ NAND_OP_PARSER_PAT_DATA_OUT_ELEM(false, 4)),
+ NAND_OP_PARSER_PATTERN(tegra_nand_cmd,
+ NAND_OP_PARSER_PAT_CMD_ELEM(true),
+ NAND_OP_PARSER_PAT_ADDR_ELEM(true, 8),
+ NAND_OP_PARSER_PAT_CMD_ELEM(true),
+ NAND_OP_PARSER_PAT_WAITRDY_ELEM(true),
+ NAND_OP_PARSER_PAT_DATA_IN_ELEM(true, 4)),
+ );
+
+static int tegra_nand_exec_op(struct nand_chip *chip,
+ const struct nand_operation *op,
+ bool check_only)
+{
+ return nand_op_parser_exec_op(chip, &tegra_nand_op_parser, op,
+ check_only);
+}
+static void tegra_nand_select_chip(struct mtd_info *mtd, int chip_nr)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct tegra_nand_controller *ctrl = to_tegra_ctrl(chip->controller);
+
+ ctrl->cur_chip = chip_nr;
+}
+
+static void tegra_nand_hw_ecc(struct tegra_nand_controller *ctrl,
+ struct nand_chip *chip, bool enable)
+{
+ u32 reg;
+
+ switch (chip->ecc.algo) {
+ case NAND_ECC_RS:
+ reg = readl_relaxed(ctrl->regs + CFG);
+ if (enable)
+ reg |= CFG_HW_ECC | CFG_ERR_COR;
+ else
+ reg &= ~(CFG_HW_ECC | CFG_ERR_COR);
+ writel_relaxed(reg, ctrl->regs + CFG);
+ break;
+ case NAND_ECC_BCH:
+ reg = readl_relaxed(ctrl->regs + BCH_CONFIG);
+ if (enable)
+ reg |= BCH_ENABLE;
+ else
+ reg &= ~BCH_ENABLE;
+ writel_relaxed(reg, ctrl->regs + BCH_CONFIG);
+ break;
+ default:
+ dev_err(ctrl->dev, "Unsupported hardware ECC algorithm\n");
+ break;
+ }
+}
+
+static int tegra_nand_page_xfer(struct mtd_info *mtd, struct nand_chip *chip,
+ void *buf, int oob_required, int page,
+ bool read)
+{
+ struct tegra_nand_controller *ctrl = to_tegra_ctrl(chip->controller);
+ struct tegra_nand_chip *nand = to_tegra_chip(chip);
+ enum dma_data_direction dir = read ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
+ dma_addr_t dma_addr;
+ u32 cmd, dma_ctrl;
+ int ret, dma_len;
+
+ if (read) {
+ writel_relaxed(NAND_CMD_READ0, ctrl->regs + CMD_1);
+ writel_relaxed(NAND_CMD_READSTART, ctrl->regs + CMD_2);
+ } else {
+ writel_relaxed(NAND_CMD_SEQIN, ctrl->regs + CMD_1);
+ writel_relaxed(NAND_CMD_PAGEPROG, ctrl->regs + CMD_2);
+ }
+ cmd = CMD_CLE | CMD_SEC_CMD;
+
+ /* Lower 16-bits are column, always 0 */
+ writel_relaxed(page << 16, ctrl->regs + ADDR_1);
+
+ if (chip->options & NAND_ROW_ADDR_3) {
+ writel_relaxed(page >> 16, ctrl->regs + ADDR_2);
+ cmd |= CMD_ALE | CMD_ALE_SIZE(5);
+ } else {
+ cmd |= CMD_ALE | CMD_ALE_SIZE(4);
+ }
+
+ dma_len = mtd->writesize + (oob_required ? mtd->oobsize : 0);
+ dma_addr = dma_map_single(ctrl->dev, buf, dma_len, dir);
+ ret = dma_mapping_error(ctrl->dev, dma_addr);
+ if (ret) {
+ dev_err(ctrl->dev, "dma mapping error\n");
+ return -EINVAL;
+ }
+
+ writel_relaxed(mtd->writesize - 1, ctrl->regs + DMA_CFG_A);
+ writel_relaxed(dma_addr, ctrl->regs + DATA_PTR);
+
+ if (oob_required) {
+ dma_addr_t dma_addr_tag = dma_addr + mtd->writesize;
+
+ writel_relaxed(nand->tag.length - 1, ctrl->regs + DMA_CFG_B);
+ writel_relaxed(dma_addr_tag + nand->tag.offset,
+ ctrl->regs + TAG_PTR);
+ } else {
+ writel_relaxed(0, ctrl->regs + DMA_CFG_B);
+ writel_relaxed(0, ctrl->regs + TAG_PTR);
+ }
+
+ dma_ctrl = DMA_CTRL_GO | DMA_CTRL_PERF_EN |
+ DMA_CTRL_IE_DONE | DMA_CTRL_IS_DONE |
+ DMA_CTRL_BURST_16 | DMA_CTRL_EN_A;
+ if (oob_required)
+ dma_ctrl |= DMA_CTRL_EN_B;
+ if (read)
+ dma_ctrl |= DMA_CTRL_IN | DMA_CTRL_REUSE;
+ else
+ dma_ctrl |= DMA_CTRL_OUT;
+
+ writel_relaxed(dma_ctrl, ctrl->regs + DMA_CTRL);
+
+ cmd |= CMD_GO | CMD_RBSY_CHK | CMD_TRANS_SIZE(9) |
+ CMD_CE(ctrl->cur_chip) | CMD_A_VALID;
+ if (oob_required)
+ cmd |= CMD_B_VALID;
+ if (read)
+ cmd |= CMD_RX;
+ else
+ cmd |= CMD_TX | CMD_AFT_DAT;
+
+ writel_relaxed(cmd, ctrl->regs + CMD);
+
+ ret = wait_for_completion_timeout(&ctrl->command_complete,
+ msecs_to_jiffies(500));
+ if (!ret) {
+ dev_err(ctrl->dev, "CMD timeout\n");
+ tegra_nand_dump_reg(ctrl);
+ ret = -ETIMEDOUT;
+ goto err_unmap_dma;
+ }
+
+ ret = wait_for_completion_timeout(&ctrl->dma_complete,
+ msecs_to_jiffies(500));
+ if (!ret) {
+ dev_err(ctrl->dev, "DMA timeout\n");
+ tegra_nand_dump_reg(ctrl);
+ ret = -ETIMEDOUT;
+ goto err_unmap_dma;
+ }
+ ret = 0;
+
+err_unmap_dma:
+ dma_unmap_single(ctrl->dev, dma_addr, dma_len, dir);
+
+ return ret;
+}
+
+static int tegra_nand_read_page_hwecc(struct mtd_info *mtd,
+ struct nand_chip *chip,
+ uint8_t *buf, int oob_required, int page)
+{
+ struct tegra_nand_controller *ctrl = to_tegra_ctrl(chip->controller);
+ u32 dec_stat, max_corr_cnt;
+ unsigned long fail_sec_flag;
+ int ret;
+
+ tegra_nand_hw_ecc(ctrl, chip, true);
+ ret = tegra_nand_page_xfer(mtd, chip, buf, oob_required, page, true);
+ tegra_nand_hw_ecc(ctrl, chip, false);
+ if (ret)
+ return ret;
+
+ /* No correctable or un-correctable errors, page must have 0 bitflips */
+ if (!ctrl->last_read_error)
+ return 0;
+
+ /*
+ * Correctable or un-correctable errors occurred. Use DEC_STAT_BUF
+ * which contains information for all ECC selections.
+ *
+ * Note that since we do not use Command Queues DEC_RESULT does not
+ * state the number of pages we can read from the DEC_STAT_BUF. But
+ * since CORRFAIL_ERR did occur during page read we do have a valid
+ * result in DEC_STAT_BUF.
+ */
+ ctrl->last_read_error = false;
+ dec_stat = readl_relaxed(ctrl->regs + DEC_STAT_BUF);
+
+ fail_sec_flag = (dec_stat & DEC_STAT_BUF_FAIL_SEC_FLAG_MASK) >>
+ DEC_STAT_BUF_FAIL_SEC_FLAG_SHIFT;
+
+ max_corr_cnt = (dec_stat & DEC_STAT_BUF_MAX_CORR_CNT_MASK) >>
+ DEC_STAT_BUF_MAX_CORR_CNT_SHIFT;
+
+ if (fail_sec_flag) {
+ int bit, max_bitflips = 0;
+
+ /*
+ * Check if all sectors in a page failed. If only some failed
+ * its definitly not an erased page and we can return error
+ * stats right away.
+ *
+ * E.g. controller might return fail_sec_flag with 0x4, which
+ * would mean only the third sector failed to correct.
+ */
+ if (fail_sec_flag ^ GENMASK(chip->ecc.steps - 1, 0)) {
+ mtd->ecc_stats.failed += hweight8(fail_sec_flag);
+ return max_corr_cnt;
+ }
+
+ /*
+ * All sectors failed to correct, but the ECC isn't smart
+ * enough to figure out if a page is really completely erased.
+ * We check the read data here to figure out if it's a
+ * legitimate ECC error or only an erased page.
+ */
+ for_each_set_bit(bit, &fail_sec_flag, chip->ecc.steps) {
+ u8 *data = buf + (chip->ecc.size * bit);
+
+ ret = nand_check_erased_ecc_chunk(data, chip->ecc.size,
+ NULL, 0,
+ NULL, 0,
+ chip->ecc.strength);
+ if (ret < 0)
+ mtd->ecc_stats.failed++;
+ else
+ max_bitflips = max(ret, max_bitflips);
+ }
+
+ return max_t(unsigned int, max_corr_cnt, max_bitflips);
+ } else {
+ int corr_sec_flag;
+
+ corr_sec_flag = (dec_stat & DEC_STAT_BUF_CORR_SEC_FLAG_MASK) >>
+ DEC_STAT_BUF_CORR_SEC_FLAG_SHIFT;
+
+ /*
+ * The value returned in the register is the maximum of
+ * bitflips encountered in any of the ECC regions. As there is
+ * no way to get the number of bitflips in a specific regions
+ * we are not able to deliver correct stats but instead
+ * overestimate the number of corrected bitflips by assuming
+ * that all regions where errors have been corrected
+ * encountered the maximum number of bitflips.
+ */
+ mtd->ecc_stats.corrected += max_corr_cnt * hweight8(corr_sec_flag);
+
+ return max_corr_cnt;
+ }
+
+}
+
+static int tegra_nand_write_page_hwecc(struct mtd_info *mtd,
+ struct nand_chip *chip,
+ const uint8_t *buf, int oob_required,
+ int page)
+{
+ struct tegra_nand_controller *ctrl = to_tegra_ctrl(chip->controller);
+ int ret;
+
+ tegra_nand_hw_ecc(ctrl, chip, true);
+ ret = tegra_nand_page_xfer(mtd, chip, (void *)buf, oob_required, page,
+ false);
+ tegra_nand_hw_ecc(ctrl, chip, false);
+
+ return ret;
+}
+
+static void tegra_nand_setup_timing(struct tegra_nand_controller *ctrl,
+ const struct nand_sdr_timings *timings)
+{
+ /*
+ * The period (and all other timings in this function) is in ps,
+ * so need to take care here to avoid integer overflows.
+ */
+ unsigned int rate = clk_get_rate(ctrl->clk) / 1000000;
+ unsigned int period = DIV_ROUND_UP(1000000, rate);
+ u32 val, reg = 0;
+
+ val = DIV_ROUND_UP(max3(timings->tAR_min, timings->tRR_min,
+ timings->tRC_min), period);
+ reg |= TIMING_TCR_TAR_TRR(OFFSET(val, 3));
+
+ val = DIV_ROUND_UP(max(max(timings->tCS_min, timings->tCH_min),
+ max(timings->tALS_min, timings->tALH_min)),
+ period);
+ reg |= TIMING_TCS(OFFSET(val, 2));
+
+ val = DIV_ROUND_UP(max(timings->tRP_min, timings->tREA_max) + 6000,
+ period);
+ reg |= TIMING_TRP(OFFSET(val, 1)) | TIMING_TRP_RESP(OFFSET(val, 1));
+
+ reg |= TIMING_TWB(OFFSET(DIV_ROUND_UP(timings->tWB_max, period), 1));
+ reg |= TIMING_TWHR(OFFSET(DIV_ROUND_UP(timings->tWHR_min, period), 1));
+ reg |= TIMING_TWH(OFFSET(DIV_ROUND_UP(timings->tWH_min, period), 1));
+ reg |= TIMING_TWP(OFFSET(DIV_ROUND_UP(timings->tWP_min, period), 1));
+ reg |= TIMING_TRH(OFFSET(DIV_ROUND_UP(timings->tREH_min, period), 1));
+
+ writel_relaxed(reg, ctrl->regs + TIMING_1);
+
+ val = DIV_ROUND_UP(timings->tADL_min, period);
+ reg = TIMING_TADL(OFFSET(val, 3));
+
+ writel_relaxed(reg, ctrl->regs + TIMING_2);
+}
+
+static int tegra_nand_setup_data_interface(struct mtd_info *mtd, int csline,
+ const struct nand_data_interface *conf)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct tegra_nand_controller *ctrl = to_tegra_ctrl(chip->controller);
+ const struct nand_sdr_timings *timings;
+
+ timings = nand_get_sdr_timings(conf);
+ if (IS_ERR(timings))
+ return PTR_ERR(timings);
+
+ if (csline == NAND_DATA_IFACE_CHECK_ONLY)
+ return 0;
+
+ tegra_nand_setup_timing(ctrl, timings);
+
+ return 0;
+}
+
+
+const int rs_strength_bootable[] = { 4 };
+const int rs_strength[] = { 4, 6, 8 };
+const int bch_strength_bootable[] = { 8, 16 };
+const int bch_strength[] = { 4, 8, 14, 16 };
+
+static int tegra_nand_get_strength(struct nand_chip *chip, const int *strength,
+ int strength_len, int oobsize)
+{
+ bool maximize = chip->ecc.options & NAND_ECC_MAXIMIZE;
+ int i;
+
+ /*
+ * Loop through available strengths. Backwards in case we try to
+ * maximize the BCH strength.
+ */
+ for (i = 0; i < strength_len; i++) {
+ int strength_sel, bytes_per_step, bytes_per_page;
+
+ if (maximize) {
+ strength_sel = strength[strength_len - i - 1];
+ } else {
+ strength_sel = strength[i];
+
+ if (strength_sel < chip->ecc_strength_ds)
+ continue;
+ }
+
+ bytes_per_step = DIV_ROUND_UP(BITS_PER_STEP_BCH * strength_sel,
+ BITS_PER_BYTE);
+ bytes_per_page = round_up(bytes_per_step * chip->ecc.steps, 4);
+
+ /* Check whether strength fits OOB */
+ if (bytes_per_page < (oobsize - SKIP_SPARE_BYTES))
+ return strength_sel;
+ }
+
+ return -EINVAL;
+}
+
+static int tegra_nand_select_strength(struct nand_chip *chip, int oobsize)
+{
+ const int *strength;
+ int strength_len;
+
+ switch (chip->ecc.algo) {
+ case NAND_ECC_RS:
+ if (chip->options & NAND_IS_BOOT_MEDIUM) {
+ strength = rs_strength_bootable;
+ strength_len = ARRAY_SIZE(rs_strength_bootable);
+ } else {
+ strength = rs_strength;
+ strength_len = ARRAY_SIZE(rs_strength);
+ }
+ break;
+ case NAND_ECC_BCH:
+ if (chip->options & NAND_IS_BOOT_MEDIUM) {
+ strength = bch_strength_bootable;
+ strength_len = ARRAY_SIZE(bch_strength_bootable);
+ } else {
+ strength = bch_strength;
+ strength_len = ARRAY_SIZE(bch_strength);
+ }
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return tegra_nand_get_strength(chip, strength, strength_len, oobsize);
+}
+
+static int tegra_nand_chips_init(struct device *dev,
+ struct tegra_nand_controller *ctrl)
+{
+ struct device_node *np = dev->of_node;
+ struct device_node *np_nand;
+ int nchips = of_get_child_count(np);
+ struct tegra_nand_chip *nand;
+ struct mtd_info *mtd;
+ struct nand_chip *chip;
+ unsigned long config, bch_config = 0;
+ int bits_per_step;
+ int ret;
+
+ if (nchips != 1) {
+ dev_err(dev, "Currently only one NAND chip supported\n");
+ return -EINVAL;
+ }
+
+ np_nand = of_get_next_child(np, NULL);
+
+ nand = devm_kzalloc(dev, sizeof(*nand), GFP_KERNEL);
+ if (!nand)
+ return -ENOMEM;
+
+ nand->wp_gpio = devm_gpiod_get_optional(dev, "wp", GPIOD_OUT_LOW);
+
+ if (IS_ERR(nand->wp_gpio)) {
+ ret = PTR_ERR(nand->wp_gpio);
+ dev_err(dev, "Failed to request WP GPIO: %d\n", ret);
+ return ret;
+ }
+
+ chip = &nand->chip;
+ chip->controller = &ctrl->controller;
+
+ mtd = nand_to_mtd(chip);
+
+ mtd->dev.parent = dev;
+ if (!mtd->name)
+ mtd->name = "tegra_nand";
+ mtd->owner = THIS_MODULE;
+
+ nand_set_flash_node(chip, np_nand);
+
+ chip->options = NAND_NO_SUBPAGE_WRITE | NAND_USE_BOUNCE_BUFFER;
+ chip->exec_op = tegra_nand_exec_op;
+ chip->select_chip = tegra_nand_select_chip;
+ chip->setup_data_interface = tegra_nand_setup_data_interface;
+
+ ret = nand_scan_ident(mtd, 1, NULL);
+ if (ret)
+ return ret;
+
+ if (chip->bbt_options & NAND_BBT_USE_FLASH)
+ chip->bbt_options |= NAND_BBT_NO_OOB;
+
+ chip->ecc.mode = NAND_ECC_HW;
+ chip->ecc.size = 512;
+ chip->ecc.steps = mtd->writesize / chip->ecc.size;
+ if (chip->ecc_step_ds != 512) {
+ dev_err(dev, "Unsupported step size %d\n", chip->ecc_step_ds);
+ return -EINVAL;
+ }
+
+ chip->ecc.read_page = tegra_nand_read_page_hwecc;
+ chip->ecc.write_page = tegra_nand_write_page_hwecc;
+
+ config = readl_relaxed(ctrl->regs + CFG);
+ config |= CFG_PIPE_EN | CFG_SKIP_SPARE | CFG_SKIP_SPARE_SIZE_4;
+
+ if (chip->options & NAND_BUSWIDTH_16)
+ config |= CFG_BUS_WIDTH_16;
+
+ if (chip->ecc.algo == NAND_ECC_UNKNOWN) {
+ if (mtd->writesize < 2048)
+ chip->ecc.algo = NAND_ECC_RS;
+ else
+ chip->ecc.algo = NAND_ECC_BCH;
+ }
+
+ if (chip->ecc.algo == NAND_ECC_BCH && mtd->writesize < 2048) {
+ dev_err(dev, "BCH supportes 2K or 4K page size only\n");
+ return -EINVAL;
+ }
+
+ if (!chip->ecc.strength) {
+ ret = tegra_nand_select_strength(chip, mtd->oobsize);
+ if (ret < 0) {
+ dev_err(dev, "No valid strenght found, minimum %d\n",
+ chip->ecc_strength_ds);
+ return ret;
+ }
+
+ chip->ecc.strength = ret;
+ }
+
+ switch (chip->ecc.algo) {
+ case NAND_ECC_RS:
+ bits_per_step = BITS_PER_STEP_RS * chip->ecc.strength;
+ mtd_set_ooblayout(mtd, &tegra_nand_oob_rs_ops);
+ switch (chip->ecc.strength) {
+ case 4:
+ config |= CFG_ECC_SEL | CFG_TVAL_4;
+ break;
+ case 6:
+ config |= CFG_ECC_SEL | CFG_TVAL_6;
+ break;
+ case 8:
+ config |= CFG_ECC_SEL | CFG_TVAL_8;
+ break;
+ default:
+ dev_err(dev, "ECC strength %d not supported\n",
+ chip->ecc.strength);
+ return -EINVAL;
+ }
+ break;
+ case NAND_ECC_BCH:
+ bits_per_step = BITS_PER_STEP_BCH * chip->ecc.strength;
+ mtd_set_ooblayout(mtd, &tegra_nand_oob_bch_ops);
+ switch (chip->ecc.strength) {
+ case 4:
+ bch_config = BCH_TVAL_4;
+ break;
+ case 8:
+ bch_config = BCH_TVAL_8;
+ break;
+ case 14:
+ bch_config = BCH_TVAL_14;
+ break;
+ case 16:
+ bch_config = BCH_TVAL_16;
+ break;
+ default:
+ dev_err(dev, "ECC strength %d not supported\n",
+ chip->ecc.strength);
+ return -EINVAL;
+ }
+ break;
+ default:
+ dev_err(dev, "ECC algorithm not supported\n");
+ return -EINVAL;
+ }
+
+ dev_info(dev, "Using %s with strength %d per 512 byte step\n",
+ chip->ecc.algo == NAND_ECC_BCH ? "BCH" : "RS",
+ chip->ecc.strength);
+
+ chip->ecc.bytes = DIV_ROUND_UP(bits_per_step, BITS_PER_BYTE);
+
+ switch (mtd->writesize) {
+ case 256:
+ config |= CFG_PS_256;
+ break;
+ case 512:
+ config |= CFG_PS_512;
+ break;
+ case 1024:
+ config |= CFG_PS_1024;
+ break;
+ case 2048:
+ config |= CFG_PS_2048;
+ break;
+ case 4096:
+ config |= CFG_PS_4096;
+ break;
+ default:
+ dev_err(dev, "Unsupported writesize %d\n", mtd->writesize);
+ return -ENODEV;
+ }
+
+ writel_relaxed(config, ctrl->regs + CFG);
+ writel_relaxed(bch_config, ctrl->regs + BCH_CONFIG);
+
+ ret = nand_scan_tail(mtd);
+ if (ret)
+ return ret;
+
+ mtd_ooblayout_free(mtd, 0, &nand->tag);
+
+ config |= CFG_TAG_BYTE_SIZE(nand->tag.length - 1);
+ writel_relaxed(config, ctrl->regs + CFG);
+
+ ret = mtd_device_register(mtd, NULL, 0);
+ if (ret) {
+ dev_err(dev, "Failed to register mtd device: %d\n", ret);
+ nand_cleanup(chip);
+ return ret;
+ }
+
+ ctrl->chip = chip;
+
+ return 0;
+}
+
+static int tegra_nand_probe(struct platform_device *pdev)
+{
+ struct reset_control *rst;
+ struct tegra_nand_controller *ctrl;
+ struct resource *res;
+ unsigned long reg;
+ int irq, err = 0;
+
+ ctrl = devm_kzalloc(&pdev->dev, sizeof(*ctrl), GFP_KERNEL);
+ if (!ctrl)
+ return -ENOMEM;
+
+ ctrl->dev = &pdev->dev;
+ nand_hw_control_init(&ctrl->controller);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ ctrl->regs = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(ctrl->regs))
+ return PTR_ERR(ctrl->regs);
+
+ rst = devm_reset_control_get(&pdev->dev, "nand");
+ if (IS_ERR(rst))
+ return PTR_ERR(rst);
+
+ ctrl->clk = devm_clk_get(&pdev->dev, "nand");
+ if (IS_ERR(ctrl->clk))
+ return PTR_ERR(ctrl->clk);
+
+ err = clk_prepare_enable(ctrl->clk);
+ if (err)
+ return err;
+
+ err = reset_control_reset(rst);
+ if (err)
+ goto err_disable_clk;
+
+ reg = HWSTATUS_RDSTATUS_MASK(1) | HWSTATUS_RDSTATUS_VALUE(0) |
+ HWSTATUS_RBSY_MASK(NAND_STATUS_READY) |
+ HWSTATUS_RBSY_VALUE(NAND_STATUS_READY);
+ writel_relaxed(NAND_CMD_STATUS, ctrl->regs + HWSTATUS_CMD);
+ writel_relaxed(reg, ctrl->regs + HWSTATUS_MASK);
+
+ init_completion(&ctrl->command_complete);
+ init_completion(&ctrl->dma_complete);
+
+ /* clear interrupts */
+ reg = readl_relaxed(ctrl->regs + ISR);
+ writel_relaxed(reg, ctrl->regs + ISR);
+
+ irq = platform_get_irq(pdev, 0);
+ err = devm_request_irq(&pdev->dev, irq, tegra_nand_irq, 0,
+ dev_name(&pdev->dev), ctrl);
+ if (err)
+ goto err_disable_clk;
+
+ writel_relaxed(DMA_CTRL_IS_DONE, ctrl->regs + DMA_CTRL);
+
+ /* enable interrupts */
+ reg = IER_UND | IER_OVR | IER_CMD_DONE | IER_GIE;
+ writel_relaxed(reg, ctrl->regs + IER);
+
+ /* reset config */
+ writel_relaxed(0, ctrl->regs + CFG);
+
+ err = tegra_nand_chips_init(ctrl->dev, ctrl);
+ if (err)
+ goto err_disable_clk;
+
+ platform_set_drvdata(pdev, ctrl);
+
+ return 0;
+
+err_disable_clk:
+ clk_disable_unprepare(ctrl->clk);
+ return err;
+}
+
+static int tegra_nand_remove(struct platform_device *pdev)
+{
+ struct tegra_nand_controller *ctrl = platform_get_drvdata(pdev);
+
+ nand_release(nand_to_mtd(ctrl->chip));
+
+ clk_disable_unprepare(ctrl->clk);
+
+ return 0;
+}
+
+static const struct of_device_id tegra_nand_of_match[] = {
+ { .compatible = "nvidia,tegra20-nand" },
+ { /* sentinel */ }
+};
+
+static struct platform_driver tegra_nand_driver = {
+ .driver = {
+ .name = "tegra-nand",
+ .of_match_table = tegra_nand_of_match,
+ },
+ .probe = tegra_nand_probe,
+ .remove = tegra_nand_remove,
+};
+module_platform_driver(tegra_nand_driver);
+
+MODULE_DESCRIPTION("NVIDIA Tegra NAND driver");
+MODULE_AUTHOR("Thierry Reding <thierry.reding@xxxxxxxxxx>");
+MODULE_AUTHOR("Lucas Stach <dev@xxxxxxxxxx>");
+MODULE_AUTHOR("Stefan Agner <stefan@xxxxxxxx>");
+MODULE_LICENSE("GPL v2");
+MODULE_DEVICE_TABLE(of, tegra_nand_of_match);
--
2.17.0