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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/mtd/nand/raw/ingenic/jz4780_bch.c
parentInitial commit. (diff)
downloadlinux-upstream/5.10.209.tar.xz
linux-upstream/5.10.209.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/mtd/nand/raw/ingenic/jz4780_bch.c')
-rw-r--r--drivers/mtd/nand/raw/ingenic/jz4780_bch.c271
1 files changed, 271 insertions, 0 deletions
diff --git a/drivers/mtd/nand/raw/ingenic/jz4780_bch.c b/drivers/mtd/nand/raw/ingenic/jz4780_bch.c
new file mode 100644
index 000000000..d67dbfff7
--- /dev/null
+++ b/drivers/mtd/nand/raw/ingenic/jz4780_bch.c
@@ -0,0 +1,271 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * JZ4780 BCH controller driver
+ *
+ * Copyright (c) 2015 Imagination Technologies
+ * Author: Alex Smith <alex.smith@imgtec.com>
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.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_BHCCR 0x8
+#define BCH_BHCNT 0xc
+#define BCH_BHDR 0x10
+#define BCH_BHPAR0 0x14
+#define BCH_BHERR0 0x84
+#define BCH_BHINT 0x184
+#define BCH_BHINTES 0x188
+#define BCH_BHINTEC 0x18c
+#define BCH_BHINTE 0x190
+
+#define BCH_BHCR_BSEL_SHIFT 4
+#define BCH_BHCR_BSEL_MASK (0x7f << BCH_BHCR_BSEL_SHIFT)
+#define BCH_BHCR_ENCE BIT(2)
+#define BCH_BHCR_INIT BIT(1)
+#define BCH_BHCR_BCHE BIT(0)
+
+#define BCH_BHCNT_PARITYSIZE_SHIFT 16
+#define BCH_BHCNT_PARITYSIZE_MASK (0x7f << BCH_BHCNT_PARITYSIZE_SHIFT)
+#define BCH_BHCNT_BLOCKSIZE_SHIFT 0
+#define BCH_BHCNT_BLOCKSIZE_MASK (0x7ff << BCH_BHCNT_BLOCKSIZE_SHIFT)
+
+#define BCH_BHERR_MASK_SHIFT 16
+#define BCH_BHERR_MASK_MASK (0xffff << BCH_BHERR_MASK_SHIFT)
+#define BCH_BHERR_INDEX_SHIFT 0
+#define BCH_BHERR_INDEX_MASK (0x7ff << BCH_BHERR_INDEX_SHIFT)
+
+#define BCH_BHINT_ERRC_SHIFT 24
+#define BCH_BHINT_ERRC_MASK (0x7f << BCH_BHINT_ERRC_SHIFT)
+#define BCH_BHINT_TERRC_SHIFT 16
+#define BCH_BHINT_TERRC_MASK (0x7f << BCH_BHINT_TERRC_SHIFT)
+#define BCH_BHINT_DECF BIT(3)
+#define BCH_BHINT_ENCF BIT(2)
+#define BCH_BHINT_UNCOR BIT(1)
+#define BCH_BHINT_ERR BIT(0)
+
+#define BCH_CLK_RATE (200 * 1000 * 1000)
+
+/* Timeout for BCH calculation/correction. */
+#define BCH_TIMEOUT_US 100000
+
+static void jz4780_bch_reset(struct ingenic_ecc *bch,
+ struct ingenic_ecc_params *params, bool encode)
+{
+ u32 reg;
+
+ /* Clear interrupt status. */
+ writel(readl(bch->base + BCH_BHINT), bch->base + BCH_BHINT);
+
+ /* Set up BCH count register. */
+ reg = params->size << BCH_BHCNT_BLOCKSIZE_SHIFT;
+ reg |= params->bytes << BCH_BHCNT_PARITYSIZE_SHIFT;
+ writel(reg, bch->base + BCH_BHCNT);
+
+ /* Initialise and enable BCH. */
+ reg = BCH_BHCR_BCHE | BCH_BHCR_INIT;
+ reg |= params->strength << BCH_BHCR_BSEL_SHIFT;
+ if (encode)
+ reg |= BCH_BHCR_ENCE;
+ writel(reg, bch->base + BCH_BHCR);
+}
+
+static void jz4780_bch_disable(struct ingenic_ecc *bch)
+{
+ writel(readl(bch->base + BCH_BHINT), bch->base + BCH_BHINT);
+ writel(BCH_BHCR_BCHE, bch->base + BCH_BHCCR);
+}
+
+static void jz4780_bch_write_data(struct ingenic_ecc *bch, const void *buf,
+ size_t size)
+{
+ size_t size32 = size / sizeof(u32);
+ size_t size8 = size % sizeof(u32);
+ const u32 *src32;
+ const u8 *src8;
+
+ src32 = (const u32 *)buf;
+ while (size32--)
+ writel(*src32++, bch->base + BCH_BHDR);
+
+ src8 = (const u8 *)src32;
+ while (size8--)
+ writeb(*src8++, bch->base + BCH_BHDR);
+}
+
+static void jz4780_bch_read_parity(struct ingenic_ecc *bch, void *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(bch->base + BCH_BHPAR0 + offset);
+ offset += sizeof(u32);
+ }
+
+ dest8 = (u8 *)dest32;
+ val = readl(bch->base + BCH_BHPAR0 + offset);
+ switch (size8) {
+ case 3:
+ dest8[2] = (val >> 16) & 0xff;
+ fallthrough;
+ case 2:
+ dest8[1] = (val >> 8) & 0xff;
+ fallthrough;
+ case 1:
+ dest8[0] = val & 0xff;
+ break;
+ }
+}
+
+static bool jz4780_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_poll_timeout(bch->base + BCH_BHINT, reg,
+ (reg & irq) == irq, 0, BCH_TIMEOUT_US);
+ if (ret)
+ return false;
+
+ if (status)
+ *status = reg;
+
+ writel(reg, bch->base + BCH_BHINT);
+ return true;
+}
+
+static int jz4780_calculate(struct ingenic_ecc *bch,
+ struct ingenic_ecc_params *params,
+ const u8 *buf, u8 *ecc_code)
+{
+ int ret = 0;
+
+ mutex_lock(&bch->lock);
+
+ jz4780_bch_reset(bch, params, true);
+ jz4780_bch_write_data(bch, buf, params->size);
+
+ if (jz4780_bch_wait_complete(bch, BCH_BHINT_ENCF, NULL)) {
+ jz4780_bch_read_parity(bch, ecc_code, params->bytes);
+ } else {
+ dev_err(bch->dev, "timed out while calculating ECC\n");
+ ret = -ETIMEDOUT;
+ }
+
+ jz4780_bch_disable(bch);
+ mutex_unlock(&bch->lock);
+ return ret;
+}
+
+static int jz4780_correct(struct ingenic_ecc *bch,
+ struct ingenic_ecc_params *params,
+ u8 *buf, u8 *ecc_code)
+{
+ u32 reg, mask, index;
+ int i, ret, count;
+
+ mutex_lock(&bch->lock);
+
+ jz4780_bch_reset(bch, params, false);
+ jz4780_bch_write_data(bch, buf, params->size);
+ jz4780_bch_write_data(bch, ecc_code, params->bytes);
+
+ if (!jz4780_bch_wait_complete(bch, BCH_BHINT_DECF, &reg)) {
+ dev_err(bch->dev, "timed out while correcting data\n");
+ ret = -ETIMEDOUT;
+ goto out;
+ }
+
+ if (reg & BCH_BHINT_UNCOR) {
+ dev_warn(bch->dev, "uncorrectable ECC error\n");
+ ret = -EBADMSG;
+ goto out;
+ }
+
+ /* Correct any detected errors. */
+ if (reg & BCH_BHINT_ERR) {
+ count = (reg & BCH_BHINT_ERRC_MASK) >> BCH_BHINT_ERRC_SHIFT;
+ ret = (reg & BCH_BHINT_TERRC_MASK) >> BCH_BHINT_TERRC_SHIFT;
+
+ for (i = 0; i < count; i++) {
+ reg = readl(bch->base + BCH_BHERR0 + (i * 4));
+ mask = (reg & BCH_BHERR_MASK_MASK) >>
+ BCH_BHERR_MASK_SHIFT;
+ index = (reg & BCH_BHERR_INDEX_MASK) >>
+ BCH_BHERR_INDEX_SHIFT;
+ buf[(index * 2) + 0] ^= mask;
+ buf[(index * 2) + 1] ^= mask >> 8;
+ }
+ } else {
+ ret = 0;
+ }
+
+out:
+ jz4780_bch_disable(bch);
+ mutex_unlock(&bch->lock);
+ return ret;
+}
+
+static int jz4780_bch_probe(struct platform_device *pdev)
+{
+ struct ingenic_ecc *bch;
+ int ret;
+
+ ret = ingenic_ecc_probe(pdev);
+ if (ret)
+ return ret;
+
+ bch = platform_get_drvdata(pdev);
+ clk_set_rate(bch->clk, BCH_CLK_RATE);
+
+ return 0;
+}
+
+static const struct ingenic_ecc_ops jz4780_bch_ops = {
+ .disable = jz4780_bch_disable,
+ .calculate = jz4780_calculate,
+ .correct = jz4780_correct,
+};
+
+static const struct of_device_id jz4780_bch_dt_match[] = {
+ { .compatible = "ingenic,jz4780-bch", .data = &jz4780_bch_ops },
+ {},
+};
+MODULE_DEVICE_TABLE(of, jz4780_bch_dt_match);
+
+static struct platform_driver jz4780_bch_driver = {
+ .probe = jz4780_bch_probe,
+ .driver = {
+ .name = "jz4780-bch",
+ .of_match_table = of_match_ptr(jz4780_bch_dt_match),
+ },
+};
+module_platform_driver(jz4780_bch_driver);
+
+MODULE_AUTHOR("Alex Smith <alex@alex-smith.me.uk>");
+MODULE_AUTHOR("Harvey Hunt <harveyhuntnexus@gmail.com>");
+MODULE_DESCRIPTION("Ingenic JZ4780 BCH error correction driver");
+MODULE_LICENSE("GPL v2");