diff options
Diffstat (limited to 'drivers/mtd/nand/raw/jz4780_bch.c')
| -rw-r--r-- | drivers/mtd/nand/raw/jz4780_bch.c | 382 |
1 files changed, 0 insertions, 382 deletions
diff --git a/drivers/mtd/nand/raw/jz4780_bch.c b/drivers/mtd/nand/raw/jz4780_bch.c deleted file mode 100644 index 7201827809e9..000000000000 --- a/drivers/mtd/nand/raw/jz4780_bch.c +++ /dev/null @@ -1,382 +0,0 @@ -/* - * JZ4780 BCH controller - * - * Copyright (c) 2015 Imagination Technologies - * Author: Alex Smith <alex.smith@imgtec.com> - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License version 2 as published - * by the Free Software Foundation. - */ - -#include <linux/bitops.h> -#include <linux/clk.h> -#include <linux/delay.h> -#include <linux/init.h> -#include <linux/iopoll.h> -#include <linux/module.h> -#include <linux/mutex.h> -#include <linux/of.h> -#include <linux/of_platform.h> -#include <linux/platform_device.h> -#include <linux/sched.h> -#include <linux/slab.h> - -#include "jz4780_bch.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 - -struct jz4780_bch { - struct device *dev; - void __iomem *base; - struct clk *clk; - struct mutex lock; -}; - -static void jz4780_bch_init(struct jz4780_bch *bch, - struct jz4780_bch_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 jz4780_bch *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 jz4780_bch *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 jz4780_bch *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; - /* fall through */ - case 2: - dest8[1] = (val >> 8) & 0xff; - /* fall through */ - case 1: - dest8[0] = val & 0xff; - break; - } -} - -static bool jz4780_bch_wait_complete(struct jz4780_bch *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; -} - -/** - * jz4780_bch_calculate() - calculate ECC for a data buffer - * @bch: BCH device. - * @params: BCH parameters. - * @buf: input buffer with raw data. - * @ecc_code: output buffer with ECC. - * - * Return: 0 on success, -ETIMEDOUT if timed out while waiting for BCH - * controller. - */ -int jz4780_bch_calculate(struct jz4780_bch *bch, struct jz4780_bch_params *params, - const u8 *buf, u8 *ecc_code) -{ - int ret = 0; - - mutex_lock(&bch->lock); - jz4780_bch_init(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; -} -EXPORT_SYMBOL(jz4780_bch_calculate); - -/** - * jz4780_bch_correct() - detect and correct bit errors - * @bch: BCH device. - * @params: BCH parameters. - * @buf: raw data read from the chip. - * @ecc_code: ECC read from the chip. - * - * Given the raw data and the ECC read from the NAND device, detects and - * corrects errors in the data. - * - * Return: the number of bit errors corrected, -EBADMSG if there are too many - * errors to correct or -ETIMEDOUT if we timed out waiting for the controller. - */ -int jz4780_bch_correct(struct jz4780_bch *bch, struct jz4780_bch_params *params, - u8 *buf, u8 *ecc_code) -{ - u32 reg, mask, index; - int i, ret, count; - - mutex_lock(&bch->lock); - - jz4780_bch_init(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, ®)) { - 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; -} -EXPORT_SYMBOL(jz4780_bch_correct); - -/** - * jz4780_bch_get() - get the BCH controller device - * @np: BCH device tree node. - * - * Gets the BCH controller device from the specified device tree node. The - * device must be released with jz4780_bch_release() when it is no longer being - * used. - * - * Return: a pointer to jz4780_bch, errors are encoded into the pointer. - * PTR_ERR(-EPROBE_DEFER) if the device hasn't been initialised yet. - */ -static struct jz4780_bch *jz4780_bch_get(struct device_node *np) -{ - struct platform_device *pdev; - struct jz4780_bch *bch; - - pdev = of_find_device_by_node(np); - if (!pdev || !platform_get_drvdata(pdev)) - return ERR_PTR(-EPROBE_DEFER); - - get_device(&pdev->dev); - - bch = platform_get_drvdata(pdev); - clk_prepare_enable(bch->clk); - - return bch; -} - -/** - * of_jz4780_bch_get() - get the BCH controller from a DT node - * @of_node: the node that contains a bch-controller property. - * - * Get the bch-controller property from the given device tree - * node and pass it to jz4780_bch_get to do the work. - * - * Return: a pointer to jz4780_bch, errors are encoded into the pointer. - * PTR_ERR(-EPROBE_DEFER) if the device hasn't been initialised yet. - */ -struct jz4780_bch *of_jz4780_bch_get(struct device_node *of_node) -{ - struct jz4780_bch *bch = NULL; - struct device_node *np; - - np = of_parse_phandle(of_node, "ingenic,bch-controller", 0); - - if (np) { - bch = jz4780_bch_get(np); - of_node_put(np); - } - return bch; -} -EXPORT_SYMBOL(of_jz4780_bch_get); - -/** - * jz4780_bch_release() - release the BCH controller device - * @bch: BCH device. - */ -void jz4780_bch_release(struct jz4780_bch *bch) -{ - clk_disable_unprepare(bch->clk); - put_device(bch->dev); -} -EXPORT_SYMBOL(jz4780_bch_release); - -static int jz4780_bch_probe(struct platform_device *pdev) -{ - struct device *dev = &pdev->dev; - struct jz4780_bch *bch; - struct resource *res; - - bch = devm_kzalloc(dev, sizeof(*bch), GFP_KERNEL); - if (!bch) - return -ENOMEM; - - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - bch->base = devm_ioremap_resource(dev, res); - if (IS_ERR(bch->base)) - return PTR_ERR(bch->base); - - jz4780_bch_disable(bch); - - bch->clk = devm_clk_get(dev, NULL); - if (IS_ERR(bch->clk)) { - dev_err(dev, "failed to get clock: %ld\n", PTR_ERR(bch->clk)); - return PTR_ERR(bch->clk); - } - - clk_set_rate(bch->clk, BCH_CLK_RATE); - - mutex_init(&bch->lock); - - bch->dev = dev; - platform_set_drvdata(pdev, bch); - - return 0; -} - -static const struct of_device_id jz4780_bch_dt_match[] = { - { .compatible = "ingenic,jz4780-bch" }, - {}, -}; -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"); |