diff options
Diffstat (limited to 'drivers/mtd/nand/ecc-mxic.c')
| -rw-r--r-- | drivers/mtd/nand/ecc-mxic.c | 880 |
1 files changed, 880 insertions, 0 deletions
diff --git a/drivers/mtd/nand/ecc-mxic.c b/drivers/mtd/nand/ecc-mxic.c new file mode 100644 index 000000000..6b487ffe2 --- /dev/null +++ b/drivers/mtd/nand/ecc-mxic.c @@ -0,0 +1,880 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Support for Macronix external hardware ECC engine for NAND devices, also + * called DPE for Data Processing Engine. + * + * Copyright © 2019 Macronix + * Author: Miquel Raynal <miquel.raynal@bootlin.com> + */ + +#include <linux/dma-mapping.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/nand.h> +#include <linux/mtd/nand-ecc-mxic.h> +#include <linux/mutex.h> +#include <linux/of_device.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +/* DPE Configuration */ +#define DP_CONFIG 0x00 +#define ECC_EN BIT(0) +#define ECC_TYP(idx) (((idx) << 3) & GENMASK(6, 3)) +/* DPE Interrupt Status */ +#define INTRPT_STS 0x04 +#define TRANS_CMPLT BIT(0) +#define SDMA_MAIN BIT(1) +#define SDMA_SPARE BIT(2) +#define ECC_ERR BIT(3) +#define TO_SPARE BIT(4) +#define TO_MAIN BIT(5) +/* DPE Interrupt Status Enable */ +#define INTRPT_STS_EN 0x08 +/* DPE Interrupt Signal Enable */ +#define INTRPT_SIG_EN 0x0C +/* Host Controller Configuration */ +#define HC_CONFIG 0x10 +#define DEV2MEM 0 /* TRANS_TYP_DMA in the spec */ +#define MEM2MEM BIT(4) /* TRANS_TYP_IO in the spec */ +#define MAPPING BIT(5) /* TRANS_TYP_MAPPING in the spec */ +#define ECC_PACKED 0 /* LAYOUT_TYP_INTEGRATED in the spec */ +#define ECC_INTERLEAVED BIT(2) /* LAYOUT_TYP_DISTRIBUTED in the spec */ +#define BURST_TYP_FIXED 0 +#define BURST_TYP_INCREASING BIT(0) +/* Host Controller Slave Address */ +#define HC_SLV_ADDR 0x14 +/* ECC Chunk Size */ +#define CHUNK_SIZE 0x20 +/* Main Data Size */ +#define MAIN_SIZE 0x24 +/* Spare Data Size */ +#define SPARE_SIZE 0x28 +#define META_SZ(reg) ((reg) & GENMASK(7, 0)) +#define PARITY_SZ(reg) (((reg) & GENMASK(15, 8)) >> 8) +#define RSV_SZ(reg) (((reg) & GENMASK(23, 16)) >> 16) +#define SPARE_SZ(reg) ((reg) >> 24) +/* ECC Chunk Count */ +#define CHUNK_CNT 0x30 +/* SDMA Control */ +#define SDMA_CTRL 0x40 +#define WRITE_NAND 0 +#define READ_NAND BIT(1) +#define CONT_NAND BIT(29) +#define CONT_SYSM BIT(30) /* Continue System Memory? */ +#define SDMA_STRT BIT(31) +/* SDMA Address of Main Data */ +#define SDMA_MAIN_ADDR 0x44 +/* SDMA Address of Spare Data */ +#define SDMA_SPARE_ADDR 0x48 +/* DPE Version Number */ +#define DP_VER 0xD0 +#define DP_VER_OFFSET 16 + +/* Status bytes between each chunk of spare data */ +#define STAT_BYTES 4 +#define NO_ERR 0x00 +#define MAX_CORR_ERR 0x28 +#define UNCORR_ERR 0xFE +#define ERASED_CHUNK 0xFF + +struct mxic_ecc_engine { + struct device *dev; + void __iomem *regs; + int irq; + struct completion complete; + struct nand_ecc_engine external_engine; + struct nand_ecc_engine pipelined_engine; + struct mutex lock; +}; + +struct mxic_ecc_ctx { + /* ECC machinery */ + unsigned int data_step_sz; + unsigned int oob_step_sz; + unsigned int parity_sz; + unsigned int meta_sz; + u8 *status; + int steps; + + /* DMA boilerplate */ + struct nand_ecc_req_tweak_ctx req_ctx; + u8 *oobwithstat; + struct scatterlist sg[2]; + struct nand_page_io_req *req; + unsigned int pageoffs; +}; + +static struct mxic_ecc_engine *ext_ecc_eng_to_mxic(struct nand_ecc_engine *eng) +{ + return container_of(eng, struct mxic_ecc_engine, external_engine); +} + +static struct mxic_ecc_engine *pip_ecc_eng_to_mxic(struct nand_ecc_engine *eng) +{ + return container_of(eng, struct mxic_ecc_engine, pipelined_engine); +} + +static struct mxic_ecc_engine *nand_to_mxic(struct nand_device *nand) +{ + struct nand_ecc_engine *eng = nand->ecc.engine; + + if (eng->integration == NAND_ECC_ENGINE_INTEGRATION_EXTERNAL) + return ext_ecc_eng_to_mxic(eng); + else + return pip_ecc_eng_to_mxic(eng); +} + +static int mxic_ecc_ooblayout_ecc(struct mtd_info *mtd, int section, + struct mtd_oob_region *oobregion) +{ + struct nand_device *nand = mtd_to_nanddev(mtd); + struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); + + if (section < 0 || section >= ctx->steps) + return -ERANGE; + + oobregion->offset = (section * ctx->oob_step_sz) + ctx->meta_sz; + oobregion->length = ctx->parity_sz; + + return 0; +} + +static int mxic_ecc_ooblayout_free(struct mtd_info *mtd, int section, + struct mtd_oob_region *oobregion) +{ + struct nand_device *nand = mtd_to_nanddev(mtd); + struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); + + if (section < 0 || section >= ctx->steps) + return -ERANGE; + + if (!section) { + oobregion->offset = 2; + oobregion->length = ctx->meta_sz - 2; + } else { + oobregion->offset = section * ctx->oob_step_sz; + oobregion->length = ctx->meta_sz; + } + + return 0; +} + +static const struct mtd_ooblayout_ops mxic_ecc_ooblayout_ops = { + .ecc = mxic_ecc_ooblayout_ecc, + .free = mxic_ecc_ooblayout_free, +}; + +static void mxic_ecc_disable_engine(struct mxic_ecc_engine *mxic) +{ + u32 reg; + + reg = readl(mxic->regs + DP_CONFIG); + reg &= ~ECC_EN; + writel(reg, mxic->regs + DP_CONFIG); +} + +static void mxic_ecc_enable_engine(struct mxic_ecc_engine *mxic) +{ + u32 reg; + + reg = readl(mxic->regs + DP_CONFIG); + reg |= ECC_EN; + writel(reg, mxic->regs + DP_CONFIG); +} + +static void mxic_ecc_disable_int(struct mxic_ecc_engine *mxic) +{ + writel(0, mxic->regs + INTRPT_SIG_EN); +} + +static void mxic_ecc_enable_int(struct mxic_ecc_engine *mxic) +{ + writel(TRANS_CMPLT, mxic->regs + INTRPT_SIG_EN); +} + +static irqreturn_t mxic_ecc_isr(int irq, void *dev_id) +{ + struct mxic_ecc_engine *mxic = dev_id; + u32 sts; + + sts = readl(mxic->regs + INTRPT_STS); + if (!sts) + return IRQ_NONE; + + if (sts & TRANS_CMPLT) + complete(&mxic->complete); + + writel(sts, mxic->regs + INTRPT_STS); + + return IRQ_HANDLED; +} + +static int mxic_ecc_init_ctx(struct nand_device *nand, struct device *dev) +{ + struct mxic_ecc_engine *mxic = nand_to_mxic(nand); + struct nand_ecc_props *conf = &nand->ecc.ctx.conf; + struct nand_ecc_props *reqs = &nand->ecc.requirements; + struct nand_ecc_props *user = &nand->ecc.user_conf; + struct mtd_info *mtd = nanddev_to_mtd(nand); + int step_size = 0, strength = 0, desired_correction = 0, steps, idx; + static const int possible_strength[] = {4, 8, 40, 48}; + static const int spare_size[] = {32, 32, 96, 96}; + struct mxic_ecc_ctx *ctx; + u32 spare_reg; + int ret; + + ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + + nand->ecc.ctx.priv = ctx; + + /* Only large page NAND chips may use BCH */ + if (mtd->oobsize < 64) { + pr_err("BCH cannot be used with small page NAND chips\n"); + return -EINVAL; + } + + mtd_set_ooblayout(mtd, &mxic_ecc_ooblayout_ops); + + /* Enable all status bits */ + writel(TRANS_CMPLT | SDMA_MAIN | SDMA_SPARE | ECC_ERR | + TO_SPARE | TO_MAIN, mxic->regs + INTRPT_STS_EN); + + /* Configure the correction depending on the NAND device topology */ + if (user->step_size && user->strength) { + step_size = user->step_size; + strength = user->strength; + } else if (reqs->step_size && reqs->strength) { + step_size = reqs->step_size; + strength = reqs->strength; + } + + if (step_size && strength) { + steps = mtd->writesize / step_size; + desired_correction = steps * strength; + } + + /* Step size is fixed to 1kiB, strength may vary (4 possible values) */ + conf->step_size = SZ_1K; + steps = mtd->writesize / conf->step_size; + + ctx->status = devm_kzalloc(dev, steps * sizeof(u8), GFP_KERNEL); + if (!ctx->status) + return -ENOMEM; + + if (desired_correction) { + strength = desired_correction / steps; + + for (idx = 0; idx < ARRAY_SIZE(possible_strength); idx++) + if (possible_strength[idx] >= strength) + break; + + idx = min_t(unsigned int, idx, + ARRAY_SIZE(possible_strength) - 1); + } else { + /* Missing data, maximize the correction */ + idx = ARRAY_SIZE(possible_strength) - 1; + } + + /* Tune the selected strength until it fits in the OOB area */ + for (; idx >= 0; idx--) { + if (spare_size[idx] * steps <= mtd->oobsize) + break; + } + + /* This engine cannot be used with this NAND device */ + if (idx < 0) + return -EINVAL; + + /* Configure the engine for the desired strength */ + writel(ECC_TYP(idx), mxic->regs + DP_CONFIG); + conf->strength = possible_strength[idx]; + spare_reg = readl(mxic->regs + SPARE_SIZE); + + ctx->steps = steps; + ctx->data_step_sz = mtd->writesize / steps; + ctx->oob_step_sz = mtd->oobsize / steps; + ctx->parity_sz = PARITY_SZ(spare_reg); + ctx->meta_sz = META_SZ(spare_reg); + + /* Ensure buffers will contain enough bytes to store the STAT_BYTES */ + ctx->req_ctx.oob_buffer_size = nanddev_per_page_oobsize(nand) + + (ctx->steps * STAT_BYTES); + ret = nand_ecc_init_req_tweaking(&ctx->req_ctx, nand); + if (ret) + return ret; + + ctx->oobwithstat = kmalloc(mtd->oobsize + (ctx->steps * STAT_BYTES), + GFP_KERNEL); + if (!ctx->oobwithstat) { + ret = -ENOMEM; + goto cleanup_req_tweak; + } + + sg_init_table(ctx->sg, 2); + + /* Configuration dump and sanity checks */ + dev_err(dev, "DPE version number: %d\n", + readl(mxic->regs + DP_VER) >> DP_VER_OFFSET); + dev_err(dev, "Chunk size: %d\n", readl(mxic->regs + CHUNK_SIZE)); + dev_err(dev, "Main size: %d\n", readl(mxic->regs + MAIN_SIZE)); + dev_err(dev, "Spare size: %d\n", SPARE_SZ(spare_reg)); + dev_err(dev, "Rsv size: %ld\n", RSV_SZ(spare_reg)); + dev_err(dev, "Parity size: %d\n", ctx->parity_sz); + dev_err(dev, "Meta size: %d\n", ctx->meta_sz); + + if ((ctx->meta_sz + ctx->parity_sz + RSV_SZ(spare_reg)) != + SPARE_SZ(spare_reg)) { + dev_err(dev, "Wrong OOB configuration: %d + %d + %ld != %d\n", + ctx->meta_sz, ctx->parity_sz, RSV_SZ(spare_reg), + SPARE_SZ(spare_reg)); + ret = -EINVAL; + goto free_oobwithstat; + } + + if (ctx->oob_step_sz != SPARE_SZ(spare_reg)) { + dev_err(dev, "Wrong OOB configuration: %d != %d\n", + ctx->oob_step_sz, SPARE_SZ(spare_reg)); + ret = -EINVAL; + goto free_oobwithstat; + } + + return 0; + +free_oobwithstat: + kfree(ctx->oobwithstat); +cleanup_req_tweak: + nand_ecc_cleanup_req_tweaking(&ctx->req_ctx); + + return ret; +} + +static int mxic_ecc_init_ctx_external(struct nand_device *nand) +{ + struct mxic_ecc_engine *mxic = nand_to_mxic(nand); + struct device *dev = nand->ecc.engine->dev; + int ret; + + dev_info(dev, "Macronix ECC engine in external mode\n"); + + ret = mxic_ecc_init_ctx(nand, dev); + if (ret) + return ret; + + /* Trigger each step manually */ + writel(1, mxic->regs + CHUNK_CNT); + writel(BURST_TYP_INCREASING | ECC_PACKED | MEM2MEM, + mxic->regs + HC_CONFIG); + + return 0; +} + +static int mxic_ecc_init_ctx_pipelined(struct nand_device *nand) +{ + struct mxic_ecc_engine *mxic = nand_to_mxic(nand); + struct mxic_ecc_ctx *ctx; + struct device *dev; + int ret; + + dev = nand_ecc_get_engine_dev(nand->ecc.engine->dev); + if (!dev) + return -EINVAL; + + dev_info(dev, "Macronix ECC engine in pipelined/mapping mode\n"); + + ret = mxic_ecc_init_ctx(nand, dev); + if (ret) + return ret; + + ctx = nand_to_ecc_ctx(nand); + + /* All steps should be handled in one go directly by the internal DMA */ + writel(ctx->steps, mxic->regs + CHUNK_CNT); + + /* + * Interleaved ECC scheme cannot be used otherwise factory bad block + * markers would be lost. A packed layout is mandatory. + */ + writel(BURST_TYP_INCREASING | ECC_PACKED | MAPPING, + mxic->regs + HC_CONFIG); + + return 0; +} + +static void mxic_ecc_cleanup_ctx(struct nand_device *nand) +{ + struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); + + if (ctx) { + nand_ecc_cleanup_req_tweaking(&ctx->req_ctx); + kfree(ctx->oobwithstat); + } +} + +static int mxic_ecc_data_xfer_wait_for_completion(struct mxic_ecc_engine *mxic) +{ + u32 val; + int ret; + + if (mxic->irq) { + reinit_completion(&mxic->complete); + mxic_ecc_enable_int(mxic); + ret = wait_for_completion_timeout(&mxic->complete, + msecs_to_jiffies(1000)); + ret = ret ? 0 : -ETIMEDOUT; + mxic_ecc_disable_int(mxic); + } else { + ret = readl_poll_timeout(mxic->regs + INTRPT_STS, val, + val & TRANS_CMPLT, 10, USEC_PER_SEC); + writel(val, mxic->regs + INTRPT_STS); + } + + if (ret) { + dev_err(mxic->dev, "Timeout on data xfer completion\n"); + return -ETIMEDOUT; + } + + return 0; +} + +static int mxic_ecc_process_data(struct mxic_ecc_engine *mxic, + unsigned int direction) +{ + unsigned int dir = (direction == NAND_PAGE_READ) ? + READ_NAND : WRITE_NAND; + int ret; + + mxic_ecc_enable_engine(mxic); + + /* Trigger processing */ + writel(SDMA_STRT | dir, mxic->regs + SDMA_CTRL); + + /* Wait for completion */ + ret = mxic_ecc_data_xfer_wait_for_completion(mxic); + + mxic_ecc_disable_engine(mxic); + + return ret; +} + +int mxic_ecc_process_data_pipelined(struct nand_ecc_engine *eng, + unsigned int direction, dma_addr_t dirmap) +{ + struct mxic_ecc_engine *mxic = pip_ecc_eng_to_mxic(eng); + + if (dirmap) + writel(dirmap, mxic->regs + HC_SLV_ADDR); + + return mxic_ecc_process_data(mxic, direction); +} +EXPORT_SYMBOL_GPL(mxic_ecc_process_data_pipelined); + +static void mxic_ecc_extract_status_bytes(struct mxic_ecc_ctx *ctx) +{ + u8 *buf = ctx->oobwithstat; + int next_stat_pos; + int step; + + /* Extract the ECC status */ + for (step = 0; step < ctx->steps; step++) { + next_stat_pos = ctx->oob_step_sz + + ((STAT_BYTES + ctx->oob_step_sz) * step); + + ctx->status[step] = buf[next_stat_pos]; + } +} + +static void mxic_ecc_reconstruct_oobbuf(struct mxic_ecc_ctx *ctx, + u8 *dst, const u8 *src) +{ + int step; + + /* Reconstruct the OOB buffer linearly (without the ECC status bytes) */ + for (step = 0; step < ctx->steps; step++) + memcpy(dst + (step * ctx->oob_step_sz), + src + (step * (ctx->oob_step_sz + STAT_BYTES)), + ctx->oob_step_sz); +} + +static void mxic_ecc_add_room_in_oobbuf(struct mxic_ecc_ctx *ctx, + u8 *dst, const u8 *src) +{ + int step; + + /* Add some space in the OOB buffer for the status bytes */ + for (step = 0; step < ctx->steps; step++) + memcpy(dst + (step * (ctx->oob_step_sz + STAT_BYTES)), + src + (step * ctx->oob_step_sz), + ctx->oob_step_sz); +} + +static int mxic_ecc_count_biterrs(struct mxic_ecc_engine *mxic, + struct nand_device *nand) +{ + struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); + struct mtd_info *mtd = nanddev_to_mtd(nand); + struct device *dev = mxic->dev; + unsigned int max_bf = 0; + bool failure = false; + int step; + + for (step = 0; step < ctx->steps; step++) { + u8 stat = ctx->status[step]; + + if (stat == NO_ERR) { + dev_dbg(dev, "ECC step %d: no error\n", step); + } else if (stat == ERASED_CHUNK) { + dev_dbg(dev, "ECC step %d: erased\n", step); + } else if (stat == UNCORR_ERR || stat > MAX_CORR_ERR) { + dev_dbg(dev, "ECC step %d: uncorrectable\n", step); + mtd->ecc_stats.failed++; + failure = true; + } else { + dev_dbg(dev, "ECC step %d: %d bits corrected\n", + step, stat); + max_bf = max_t(unsigned int, max_bf, stat); + mtd->ecc_stats.corrected += stat; + } + } + + return failure ? -EBADMSG : max_bf; +} + +/* External ECC engine helpers */ +static int mxic_ecc_prepare_io_req_external(struct nand_device *nand, + struct nand_page_io_req *req) +{ + struct mxic_ecc_engine *mxic = nand_to_mxic(nand); + struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); + struct mtd_info *mtd = nanddev_to_mtd(nand); + int offset, nents, step, ret; + + if (req->mode == MTD_OPS_RAW) + return 0; + + nand_ecc_tweak_req(&ctx->req_ctx, req); + ctx->req = req; + + if (req->type == NAND_PAGE_READ) + return 0; + + mxic_ecc_add_room_in_oobbuf(ctx, ctx->oobwithstat, + ctx->req->oobbuf.out); + + sg_set_buf(&ctx->sg[0], req->databuf.out, req->datalen); + sg_set_buf(&ctx->sg[1], ctx->oobwithstat, + req->ooblen + (ctx->steps * STAT_BYTES)); + + nents = dma_map_sg(mxic->dev, ctx->sg, 2, DMA_BIDIRECTIONAL); + if (!nents) + return -EINVAL; + + mutex_lock(&mxic->lock); + + for (step = 0; step < ctx->steps; step++) { + writel(sg_dma_address(&ctx->sg[0]) + (step * ctx->data_step_sz), + mxic->regs + SDMA_MAIN_ADDR); + writel(sg_dma_address(&ctx->sg[1]) + (step * (ctx->oob_step_sz + STAT_BYTES)), + mxic->regs + SDMA_SPARE_ADDR); + ret = mxic_ecc_process_data(mxic, ctx->req->type); + if (ret) + break; + } + + mutex_unlock(&mxic->lock); + + dma_unmap_sg(mxic->dev, ctx->sg, 2, DMA_BIDIRECTIONAL); + + if (ret) + return ret; + + /* Retrieve the calculated ECC bytes */ + for (step = 0; step < ctx->steps; step++) { + offset = ctx->meta_sz + (step * ctx->oob_step_sz); + mtd_ooblayout_get_eccbytes(mtd, + (u8 *)ctx->req->oobbuf.out + offset, + ctx->oobwithstat + (step * STAT_BYTES), + step * ctx->parity_sz, + ctx->parity_sz); + } + + return 0; +} + +static int mxic_ecc_finish_io_req_external(struct nand_device *nand, + struct nand_page_io_req *req) +{ + struct mxic_ecc_engine *mxic = nand_to_mxic(nand); + struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); + int nents, step, ret; + + if (req->mode == MTD_OPS_RAW) + return 0; + + if (req->type == NAND_PAGE_WRITE) { + nand_ecc_restore_req(&ctx->req_ctx, req); + return 0; + } + + /* Copy the OOB buffer and add room for the ECC engine status bytes */ + mxic_ecc_add_room_in_oobbuf(ctx, ctx->oobwithstat, ctx->req->oobbuf.in); + + sg_set_buf(&ctx->sg[0], req->databuf.in, req->datalen); + sg_set_buf(&ctx->sg[1], ctx->oobwithstat, + req->ooblen + (ctx->steps * STAT_BYTES)); + nents = dma_map_sg(mxic->dev, ctx->sg, 2, DMA_BIDIRECTIONAL); + if (!nents) + return -EINVAL; + + mutex_lock(&mxic->lock); + + for (step = 0; step < ctx->steps; step++) { + writel(sg_dma_address(&ctx->sg[0]) + (step * ctx->data_step_sz), + mxic->regs + SDMA_MAIN_ADDR); + writel(sg_dma_address(&ctx->sg[1]) + (step * (ctx->oob_step_sz + STAT_BYTES)), + mxic->regs + SDMA_SPARE_ADDR); + ret = mxic_ecc_process_data(mxic, ctx->req->type); + if (ret) + break; + } + + mutex_unlock(&mxic->lock); + + dma_unmap_sg(mxic->dev, ctx->sg, 2, DMA_BIDIRECTIONAL); + + if (ret) { + nand_ecc_restore_req(&ctx->req_ctx, req); + return ret; + } + + /* Extract the status bytes and reconstruct the buffer */ + mxic_ecc_extract_status_bytes(ctx); + mxic_ecc_reconstruct_oobbuf(ctx, ctx->req->oobbuf.in, ctx->oobwithstat); + + nand_ecc_restore_req(&ctx->req_ctx, req); + + return mxic_ecc_count_biterrs(mxic, nand); +} + +/* Pipelined ECC engine helpers */ +static int mxic_ecc_prepare_io_req_pipelined(struct nand_device *nand, + struct nand_page_io_req *req) +{ + struct mxic_ecc_engine *mxic = nand_to_mxic(nand); + struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); + int nents; + + if (req->mode == MTD_OPS_RAW) + return 0; + + nand_ecc_tweak_req(&ctx->req_ctx, req); + ctx->req = req; + + /* Copy the OOB buffer and add room for the ECC engine status bytes */ + mxic_ecc_add_room_in_oobbuf(ctx, ctx->oobwithstat, ctx->req->oobbuf.in); + + sg_set_buf(&ctx->sg[0], req->databuf.in, req->datalen); + sg_set_buf(&ctx->sg[1], ctx->oobwithstat, + req->ooblen + (ctx->steps * STAT_BYTES)); + + nents = dma_map_sg(mxic->dev, ctx->sg, 2, DMA_BIDIRECTIONAL); + if (!nents) + return -EINVAL; + + mutex_lock(&mxic->lock); + + writel(sg_dma_address(&ctx->sg[0]), mxic->regs + SDMA_MAIN_ADDR); + writel(sg_dma_address(&ctx->sg[1]), mxic->regs + SDMA_SPARE_ADDR); + + return 0; +} + +static int mxic_ecc_finish_io_req_pipelined(struct nand_device *nand, + struct nand_page_io_req *req) +{ + struct mxic_ecc_engine *mxic = nand_to_mxic(nand); + struct mxic_ecc_ctx *ctx = nand_to_ecc_ctx(nand); + int ret = 0; + + if (req->mode == MTD_OPS_RAW) + return 0; + + mutex_unlock(&mxic->lock); + + dma_unmap_sg(mxic->dev, ctx->sg, 2, DMA_BIDIRECTIONAL); + + if (req->type == NAND_PAGE_READ) { + mxic_ecc_extract_status_bytes(ctx); + mxic_ecc_reconstruct_oobbuf(ctx, ctx->req->oobbuf.in, + ctx->oobwithstat); + ret = mxic_ecc_count_biterrs(mxic, nand); + } + + nand_ecc_restore_req(&ctx->req_ctx, req); + + return ret; +} + +static struct nand_ecc_engine_ops mxic_ecc_engine_external_ops = { + .init_ctx = mxic_ecc_init_ctx_external, + .cleanup_ctx = mxic_ecc_cleanup_ctx, + .prepare_io_req = mxic_ecc_prepare_io_req_external, + .finish_io_req = mxic_ecc_finish_io_req_external, +}; + +static struct nand_ecc_engine_ops mxic_ecc_engine_pipelined_ops = { + .init_ctx = mxic_ecc_init_ctx_pipelined, + .cleanup_ctx = mxic_ecc_cleanup_ctx, + .prepare_io_req = mxic_ecc_prepare_io_req_pipelined, + .finish_io_req = mxic_ecc_finish_io_req_pipelined, +}; + +struct nand_ecc_engine_ops *mxic_ecc_get_pipelined_ops(void) +{ + return &mxic_ecc_engine_pipelined_ops; +} +EXPORT_SYMBOL_GPL(mxic_ecc_get_pipelined_ops); + +static struct platform_device * +mxic_ecc_get_pdev(struct platform_device *spi_pdev) +{ + struct platform_device *eng_pdev; + struct device_node *np; + + /* Retrieve the nand-ecc-engine phandle */ + np = of_parse_phandle(spi_pdev->dev.of_node, "nand-ecc-engine", 0); + if (!np) + return NULL; + + /* Jump to the engine's device node */ + eng_pdev = of_find_device_by_node(np); + of_node_put(np); + + return eng_pdev; +} + +void mxic_ecc_put_pipelined_engine(struct nand_ecc_engine *eng) +{ + struct mxic_ecc_engine *mxic = pip_ecc_eng_to_mxic(eng); + + platform_device_put(to_platform_device(mxic->dev)); +} +EXPORT_SYMBOL_GPL(mxic_ecc_put_pipelined_engine); + +struct nand_ecc_engine * +mxic_ecc_get_pipelined_engine(struct platform_device *spi_pdev) +{ + struct platform_device *eng_pdev; + struct mxic_ecc_engine *mxic; + + eng_pdev = mxic_ecc_get_pdev(spi_pdev); + if (!eng_pdev) + return ERR_PTR(-ENODEV); + + mxic = platform_get_drvdata(eng_pdev); + if (!mxic) { + platform_device_put(eng_pdev); + return ERR_PTR(-EPROBE_DEFER); + } + + return &mxic->pipelined_engine; +} +EXPORT_SYMBOL_GPL(mxic_ecc_get_pipelined_engine); + +/* + * Only the external ECC engine is exported as the pipelined is SoC specific, so + * it is registered directly by the drivers that wrap it. + */ +static int mxic_ecc_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct mxic_ecc_engine *mxic; + int ret; + + mxic = devm_kzalloc(&pdev->dev, sizeof(*mxic), GFP_KERNEL); + if (!mxic) + return -ENOMEM; + + mxic->dev = &pdev->dev; + + /* + * Both memory regions for the ECC engine itself and the AXI slave + * address are mandatory. + */ + mxic->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(mxic->regs)) { + dev_err(&pdev->dev, "Missing memory region\n"); + return PTR_ERR(mxic->regs); + } + + mxic_ecc_disable_engine(mxic); + mxic_ecc_disable_int(mxic); + + /* IRQ is optional yet much more efficient */ + mxic->irq = platform_get_irq_byname_optional(pdev, "ecc-engine"); + if (mxic->irq > 0) { + ret = devm_request_irq(&pdev->dev, mxic->irq, mxic_ecc_isr, 0, + "mxic-ecc", mxic); + if (ret) + return ret; + } else { + dev_info(dev, "Invalid or missing IRQ, fallback to polling\n"); + mxic->irq = 0; + } + + mutex_init(&mxic->lock); + + /* + * In external mode, the device is the ECC engine. In pipelined mode, + * the device is the host controller. The device is used to match the + * right ECC engine based on the DT properties. + */ + mxic->external_engine.dev = &pdev->dev; + mxic->external_engine.integration = NAND_ECC_ENGINE_INTEGRATION_EXTERNAL; + mxic->external_engine.ops = &mxic_ecc_engine_external_ops; + + nand_ecc_register_on_host_hw_engine(&mxic->external_engine); + + platform_set_drvdata(pdev, mxic); + + return 0; +} + +static int mxic_ecc_remove(struct platform_device *pdev) +{ + struct mxic_ecc_engine *mxic = platform_get_drvdata(pdev); + + nand_ecc_unregister_on_host_hw_engine(&mxic->external_engine); + + return 0; +} + +static const struct of_device_id mxic_ecc_of_ids[] = { + { + .compatible = "mxicy,nand-ecc-engine-rev3", + }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, mxic_ecc_of_ids); + +static struct platform_driver mxic_ecc_driver = { + .driver = { + .name = "mxic-nand-ecc-engine", + .of_match_table = mxic_ecc_of_ids, + }, + .probe = mxic_ecc_probe, + .remove = mxic_ecc_remove, +}; +module_platform_driver(mxic_ecc_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Miquel Raynal <miquel.raynal@bootlin.com>"); +MODULE_DESCRIPTION("Macronix NAND hardware ECC controller"); |