[PATCH v5 11/12] mtd: rawnand: ingenic: Add support for the JZ4725B

From: Paul Cercueil
Date: Wed Mar 13 2019 - 18:23:28 EST


The boot ROM of the JZ4725B SoC expects a specific OOB layout on the
NAND, so we use it unconditionally in the ingenic-nand driver.

Also add the jz4725b-bch driver to support the JZ4725B-specific BCH
hardware.

Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
---

Notes:
v2: Instead of forcing the OOB layout, leave it to the board code or
devicetree to decide if the jz4725b-specific layout should be used
or not.

v3: - Revert the change in v2, as the previous behaviour was correct.
- Also add support for the hardware BCH of the JZ4725B in this
patch.

v4: - Add MODULE_* macros
- Add tweaks suggested by upstream feedback

v5: - Rename jz4740_ecc_init to jz4740_ecc_reset

drivers/mtd/nand/raw/ingenic/Kconfig | 10 +
drivers/mtd/nand/raw/ingenic/Makefile | 1 +
drivers/mtd/nand/raw/ingenic/ingenic_nand.c | 48 ++++-
drivers/mtd/nand/raw/ingenic/jz4725b_bch.c | 293 ++++++++++++++++++++++++++++
4 files changed, 351 insertions(+), 1 deletion(-)
create mode 100644 drivers/mtd/nand/raw/ingenic/jz4725b_bch.c

diff --git a/drivers/mtd/nand/raw/ingenic/Kconfig b/drivers/mtd/nand/raw/ingenic/Kconfig
index cc663cc15119..497b46b144f2 100644
--- a/drivers/mtd/nand/raw/ingenic/Kconfig
+++ b/drivers/mtd/nand/raw/ingenic/Kconfig
@@ -27,6 +27,16 @@ config MTD_NAND_JZ4740_ECC
This driver can also be built as a module. If so, the module
will be called jz4740-ecc.

+config MTD_NAND_JZ4725B_BCH
+ tristate "Hardware BCH support for JZ4725B SoC"
+ select MTD_NAND_INGENIC_ECC
+ help
+ Enable this driver to support the BCH error-correction hardware
+ present on the JZ4725B SoC from Ingenic.
+
+ This driver can also be built as a module. If so, the module
+ will be called jz4725b-bch.
+
config MTD_NAND_JZ4780_BCH
tristate "Hardware BCH support for JZ4780 SoC"
select MTD_NAND_INGENIC_ECC
diff --git a/drivers/mtd/nand/raw/ingenic/Makefile b/drivers/mtd/nand/raw/ingenic/Makefile
index 563b7effcf59..ab2c5f47e5b7 100644
--- a/drivers/mtd/nand/raw/ingenic/Makefile
+++ b/drivers/mtd/nand/raw/ingenic/Makefile
@@ -3,4 +3,5 @@ obj-$(CONFIG_MTD_NAND_JZ4780) += ingenic_nand.o

obj-$(CONFIG_MTD_NAND_INGENIC_ECC) += ingenic_ecc.o
obj-$(CONFIG_MTD_NAND_JZ4740_ECC) += jz4740_ecc.o
+obj-$(CONFIG_MTD_NAND_JZ4725B_BCH) += jz4725b_bch.o
obj-$(CONFIG_MTD_NAND_JZ4780_BCH) += jz4780_bch.o
diff --git a/drivers/mtd/nand/raw/ingenic/ingenic_nand.c b/drivers/mtd/nand/raw/ingenic/ingenic_nand.c
index 1bd1f18d4532..a2450e10932a 100644
--- a/drivers/mtd/nand/raw/ingenic/ingenic_nand.c
+++ b/drivers/mtd/nand/raw/ingenic/ingenic_nand.c
@@ -34,6 +34,7 @@ struct jz_soc_info {
unsigned long data_offset;
unsigned long addr_offset;
unsigned long cmd_offset;
+ const struct mtd_ooblayout_ops *oob_layout;
};

struct ingenic_nand_cs {
@@ -71,6 +72,41 @@ static inline struct ingenic_nfc *to_ingenic_nfc(struct nand_controller *ctrl)
return container_of(ctrl, struct ingenic_nfc, controller);
}

+static int jz4725b_ooblayout_ecc(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+
+ if (section || !ecc->total)
+ return -ERANGE;
+
+ oobregion->length = ecc->total;
+ oobregion->offset = 3;
+
+ return 0;
+}
+
+static int jz4725b_ooblayout_free(struct mtd_info *mtd, int section,
+ struct mtd_oob_region *oobregion)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+
+ if (section)
+ return -ERANGE;
+
+ oobregion->length = mtd->oobsize - ecc->total - 3;
+ oobregion->offset = 3 + ecc->total;
+
+ return 0;
+}
+
+const struct mtd_ooblayout_ops jz4725b_ooblayout_ops = {
+ .ecc = jz4725b_ooblayout_ecc,
+ .free = jz4725b_ooblayout_free,
+};
+
static void ingenic_nand_select_chip(struct nand_chip *chip, int chipnr)
{
struct ingenic_nand *nand = to_ingenic_nand(nand_to_mtd(chip));
@@ -211,7 +247,7 @@ static int ingenic_nand_attach_chip(struct nand_chip *chip)
return -EINVAL;
}

- mtd_set_ooblayout(mtd, &nand_ooblayout_lp_ops);
+ mtd_set_ooblayout(mtd, nfc->soc_info->oob_layout);

return 0;
}
@@ -407,16 +443,26 @@ static const struct jz_soc_info jz4740_soc_info = {
.data_offset = 0x00000000,
.cmd_offset = 0x00008000,
.addr_offset = 0x00010000,
+ .oob_layout = &nand_ooblayout_lp_ops,
+};
+
+static const struct jz_soc_info jz4725b_soc_info = {
+ .data_offset = 0x00000000,
+ .cmd_offset = 0x00008000,
+ .addr_offset = 0x00010000,
+ .oob_layout = &jz4725b_ooblayout_ops,
};

static const struct jz_soc_info jz4780_soc_info = {
.data_offset = 0x00000000,
.cmd_offset = 0x00400000,
.addr_offset = 0x00800000,
+ .oob_layout = &nand_ooblayout_lp_ops,
};

static const struct of_device_id ingenic_nand_dt_match[] = {
{ .compatible = "ingenic,jz4740-nand", .data = &jz4740_soc_info },
+ { .compatible = "ingenic,jz4725b-nand", .data = &jz4725b_soc_info },
{ .compatible = "ingenic,jz4780-nand", .data = &jz4780_soc_info },
{},
};
diff --git a/drivers/mtd/nand/raw/ingenic/jz4725b_bch.c b/drivers/mtd/nand/raw/ingenic/jz4725b_bch.c
new file mode 100644
index 000000000000..355fee4d3e1c
--- /dev/null
+++ b/drivers/mtd/nand/raw/ingenic/jz4725b_bch.c
@@ -0,0 +1,293 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * JZ4725B BCH controller driver
+ *
+ * Copyright (C) 2019 Paul Cercueil <paul@xxxxxxxxxxxxxxx>
+ *
+ * Based on jz4780_bch.c
+ */
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+
+#include "ingenic_ecc.h"
+
+#define BCH_BHCR 0x0
+#define BCH_BHCSR 0x4
+#define BCH_BHCCR 0x8
+#define BCH_BHCNT 0xc
+#define BCH_BHDR 0x10
+#define BCH_BHPAR0 0x14
+#define BCH_BHERR0 0x28
+#define BCH_BHINT 0x24
+#define BCH_BHINTES 0x3c
+#define BCH_BHINTEC 0x40
+#define BCH_BHINTE 0x38
+
+#define BCH_BHCR_ENCE BIT(3)
+#define BCH_BHCR_BSEL BIT(2)
+#define BCH_BHCR_INIT BIT(1)
+#define BCH_BHCR_BCHE BIT(0)
+
+#define BCH_BHCNT_DEC_COUNT_SHIFT 16
+#define BCH_BHCNT_DEC_COUNT_MASK (0x3ff << BCH_BHCNT_DEC_COUNT_SHIFT)
+#define BCH_BHCNT_ENC_COUNT_SHIFT 0
+#define BCH_BHCNT_ENC_COUNT_MASK (0x3ff << BCH_BHCNT_ENC_COUNT_SHIFT)
+
+#define BCH_BHERR_INDEX0_SHIFT 0
+#define BCH_BHERR_INDEX0_MASK (0x1fff << BCH_BHERR_INDEX0_SHIFT)
+#define BCH_BHERR_INDEX1_SHIFT 16
+#define BCH_BHERR_INDEX1_MASK (0x1fff << BCH_BHERR_INDEX1_SHIFT)
+
+#define BCH_BHINT_ERRC_SHIFT 28
+#define BCH_BHINT_ERRC_MASK (0xf << BCH_BHINT_ERRC_SHIFT)
+#define BCH_BHINT_TERRC_SHIFT 16
+#define BCH_BHINT_TERRC_MASK (0x7f << BCH_BHINT_TERRC_SHIFT)
+#define BCH_BHINT_ALL_0 BIT(5)
+#define BCH_BHINT_ALL_F BIT(4)
+#define BCH_BHINT_DECF BIT(3)
+#define BCH_BHINT_ENCF BIT(2)
+#define BCH_BHINT_UNCOR BIT(1)
+#define BCH_BHINT_ERR BIT(0)
+
+/* Timeout for BCH calculation/correction. */
+#define BCH_TIMEOUT_US 100000
+
+static inline void jz4725b_bch_config_set(struct ingenic_ecc *bch, u32 cfg)
+{
+ writel(cfg, bch->base + BCH_BHCSR);
+}
+
+static inline void jz4725b_bch_config_clear(struct ingenic_ecc *bch, u32 cfg)
+{
+ writel(cfg, bch->base + BCH_BHCCR);
+}
+
+static int jz4725b_bch_reset(struct ingenic_ecc *bch,
+ struct ingenic_ecc_params *params, bool calc_ecc)
+{
+ u32 reg, max_value;
+
+ /* Clear interrupt status. */
+ writel(readl(bch->base + BCH_BHINT), bch->base + BCH_BHINT);
+
+ /* Initialise and enable BCH. */
+ jz4725b_bch_config_clear(bch, 0x1f);
+ jz4725b_bch_config_set(bch, BCH_BHCR_BCHE);
+
+ if (params->strength == 8)
+ jz4725b_bch_config_set(bch, BCH_BHCR_BSEL);
+ else
+ jz4725b_bch_config_clear(bch, BCH_BHCR_BSEL);
+
+ if (calc_ecc) /* calculate ECC from data */
+ jz4725b_bch_config_set(bch, BCH_BHCR_ENCE);
+ else /* correct data from ECC */
+ jz4725b_bch_config_clear(bch, BCH_BHCR_ENCE);
+
+ jz4725b_bch_config_set(bch, BCH_BHCR_INIT);
+
+ max_value = BCH_BHCNT_ENC_COUNT_MASK >> BCH_BHCNT_ENC_COUNT_SHIFT;
+ if (params->size > max_value)
+ return -EINVAL;
+
+ max_value = BCH_BHCNT_DEC_COUNT_MASK >> BCH_BHCNT_DEC_COUNT_SHIFT;
+ if (params->size + params->bytes > max_value)
+ return -EINVAL;
+
+ /* Set up BCH count register. */
+ reg = params->size << BCH_BHCNT_ENC_COUNT_SHIFT;
+ reg |= (params->size + params->bytes) << BCH_BHCNT_DEC_COUNT_SHIFT;
+ writel(reg, bch->base + BCH_BHCNT);
+
+ return 0;
+}
+
+static void jz4725b_bch_disable(struct ingenic_ecc *bch)
+{
+ /* Clear interrupts */
+ writel(readl(bch->base + BCH_BHINT), bch->base + BCH_BHINT);
+
+ /* Disable the hardware */
+ jz4725b_bch_config_clear(bch, BCH_BHCR_BCHE);
+}
+
+static void jz4725b_bch_write_data(struct ingenic_ecc *bch, const u8 *buf,
+ size_t size)
+{
+ while (size--)
+ writeb(*buf++, bch->base + BCH_BHDR);
+}
+
+static void jz4725b_bch_read_parity(struct ingenic_ecc *bch, u8 *buf,
+ size_t size)
+{
+ size_t size32 = size / sizeof(u32);
+ size_t size8 = size % sizeof(u32);
+ u32 *dest32;
+ u8 *dest8;
+ u32 val, offset = 0;
+
+ dest32 = (u32 *)buf;
+ while (size32--) {
+ *dest32++ = readl_relaxed(bch->base + BCH_BHPAR0 + offset);
+ offset += sizeof(u32);
+ }
+
+ dest8 = (u8 *)dest32;
+ val = readl_relaxed(bch->base + BCH_BHPAR0 + offset);
+ switch (size8) {
+ case 3:
+ dest8[2] = (val >> 16) & 0xff;
+ case 2: /* fall-through */
+ dest8[1] = (val >> 8) & 0xff;
+ case 1: /* fall-through */
+ dest8[0] = val & 0xff;
+ break;
+ }
+}
+
+static int jz4725b_bch_wait_complete(struct ingenic_ecc *bch, unsigned int irq,
+ u32 *status)
+{
+ u32 reg;
+ int ret;
+
+ /*
+ * While we could use interrupts here and sleep until the operation
+ * completes, the controller works fairly quickly (usually a few
+ * microseconds) and so the overhead of sleeping until we get an
+ * interrupt quite noticeably decreases performance.
+ */
+ ret = readl_relaxed_poll_timeout(bch->base + BCH_BHINT, reg,
+ reg & irq, 0, BCH_TIMEOUT_US);
+ if (ret)
+ return ret;
+
+ if (status)
+ *status = reg;
+
+ writel(reg, bch->base + BCH_BHINT);
+
+ return 0;
+}
+
+static int jz4725b_calculate(struct ingenic_ecc *bch,
+ struct ingenic_ecc_params *params,
+ const u8 *buf, u8 *ecc_code)
+{
+ int ret;
+
+ mutex_lock(&bch->lock);
+
+ ret = jz4725b_bch_reset(bch, params, true);
+ if (ret) {
+ dev_err(bch->dev, "Unable to init BCH with given parameters\n");
+ goto out_disable;
+ }
+
+ jz4725b_bch_write_data(bch, buf, params->size);
+
+ ret = jz4725b_bch_wait_complete(bch, BCH_BHINT_ENCF, NULL);
+ if (ret) {
+ dev_err(bch->dev, "timed out while calculating ECC\n");
+ goto out_disable;
+ }
+
+ jz4725b_bch_read_parity(bch, ecc_code, params->bytes);
+
+out_disable:
+ jz4725b_bch_disable(bch);
+ mutex_unlock(&bch->lock);
+
+ return ret;
+}
+
+static int jz4725b_correct(struct ingenic_ecc *bch,
+ struct ingenic_ecc_params *params,
+ u8 *buf, u8 *ecc_code)
+{
+ u32 reg, errors, bit;
+ unsigned int i;
+ int ret;
+
+ mutex_lock(&bch->lock);
+
+ ret = jz4725b_bch_reset(bch, params, false);
+ if (ret) {
+ dev_err(bch->dev, "Unable to init BCH with given parameters\n");
+ goto out;
+ }
+
+ jz4725b_bch_write_data(bch, buf, params->size);
+ jz4725b_bch_write_data(bch, ecc_code, params->bytes);
+
+ ret = jz4725b_bch_wait_complete(bch, BCH_BHINT_DECF, &reg);
+ if (ret) {
+ dev_err(bch->dev, "timed out while correcting data\n");
+ goto out;
+ }
+
+ if (reg & (BCH_BHINT_ALL_F | BCH_BHINT_ALL_0)) {
+ /* Data and ECC is all 0xff or 0x00 - nothing to correct */
+ ret = 0;
+ goto out;
+ }
+
+ if (reg & BCH_BHINT_UNCOR) {
+ /* Uncorrectable ECC error */
+ ret = -EBADMSG;
+ goto out;
+ }
+
+ errors = (reg & BCH_BHINT_ERRC_MASK) >> BCH_BHINT_ERRC_SHIFT;
+
+ /* Correct any detected errors. */
+ for (i = 0; i < errors; i++) {
+ if (i & 1) {
+ bit = (reg & BCH_BHERR_INDEX1_MASK) >> BCH_BHERR_INDEX1_SHIFT;
+ } else {
+ reg = readl(bch->base + BCH_BHERR0 + (i * 4));
+ bit = (reg & BCH_BHERR_INDEX0_MASK) >> BCH_BHERR_INDEX0_SHIFT;
+ }
+
+ buf[(bit >> 3)] ^= BIT(bit & 0x7);
+ }
+
+out:
+ jz4725b_bch_disable(bch);
+ mutex_unlock(&bch->lock);
+
+ return ret;
+}
+
+static const struct ingenic_ecc_ops jz4725b_bch_ops = {
+ .disable = jz4725b_bch_disable,
+ .calculate = jz4725b_calculate,
+ .correct = jz4725b_correct,
+};
+
+static const struct of_device_id jz4725b_bch_dt_match[] = {
+ { .compatible = "ingenic,jz4725b-bch", .data = &jz4725b_bch_ops },
+ {},
+};
+MODULE_DEVICE_TABLE(of, jz4725b_bch_dt_match);
+
+static struct platform_driver jz4725b_bch_driver = {
+ .probe = ingenic_ecc_probe,
+ .driver = {
+ .name = "jz4725b-bch",
+ .of_match_table = jz4725b_bch_dt_match,
+ },
+};
+module_platform_driver(jz4725b_bch_driver);
+
+MODULE_AUTHOR("Paul Cercueil <paul@xxxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Ingenic JZ4725B BCH controller driver");
+MODULE_LICENSE("GPL v2");
--
2.11.0