}
EXPORT_SYMBOL(nand_ecc_sw_bch_correct);
+/**
+ * nand_ecc_sw_bch_cleanup - Cleanup software BCH ECC resources
+ * @nand: NAND device
+ */
+static void nand_ecc_sw_bch_cleanup(struct nand_device *nand)
+{
+ struct nand_ecc_sw_bch_conf *engine_conf = nand->ecc.ctx.priv;
+
+ bch_free(engine_conf->bch);
+ kfree(engine_conf->errloc);
+ kfree(engine_conf->eccmask);
+}
+
/**
* nand_ecc_sw_bch_init - Initialize software BCH ECC engine
* @nand: NAND device
* step_size = 512 (thus, m = 13 is the smallest integer such that 2^m - 1 > 512 * 8)
* bytes = 7 (7 bytes are required to store m * t = 13 * 4 = 52 bits)
*/
-int nand_ecc_sw_bch_init(struct nand_device *nand)
+static int nand_ecc_sw_bch_init(struct nand_device *nand)
{
- struct mtd_info *mtd = nanddev_to_mtd(nand);
- unsigned int m, t, eccsteps, i;
struct nand_ecc_sw_bch_conf *engine_conf = nand->ecc.ctx.priv;
- unsigned char *erased_page;
unsigned int eccsize = nand->ecc.ctx.conf.step_size;
unsigned int eccbytes = engine_conf->code_size;
- unsigned int eccstrength = nand->ecc.ctx.conf.strength;
-
- if (!eccbytes && eccstrength) {
- eccbytes = DIV_ROUND_UP(eccstrength * fls(8 * eccsize), 8);
- engine_conf->code_size = eccbytes;
- }
-
- if (!eccsize || !eccbytes) {
- pr_warn("ecc parameters not supplied\n");
- return -EINVAL;
- }
+ unsigned int m, t, i;
+ unsigned char *erased_page;
+ int ret;
- m = fls(1+8*eccsize);
- t = (eccbytes*8)/m;
+ m = fls(1 + (8 * eccsize));
+ t = (eccbytes * 8) / m;
engine_conf->bch = bch_init(m, t, 0, false);
if (!engine_conf->bch)
return -EINVAL;
- /* verify that eccbytes has the expected value */
- if (engine_conf->bch->ecc_bytes != eccbytes) {
- pr_warn("invalid eccbytes %u, should be %u\n",
- eccbytes, engine_conf->bch->ecc_bytes);
- goto fail;
+ engine_conf->eccmask = kzalloc(eccbytes, GFP_KERNEL);
+ engine_conf->errloc = kmalloc_array(t, sizeof(*engine_conf->errloc),
+ GFP_KERNEL);
+ if (!engine_conf->eccmask || !engine_conf->errloc) {
+ ret = -ENOMEM;
+ goto cleanup;
+ }
+
+ /* Compute and store the inverted ECC of an erased step */
+ erased_page = kmalloc(eccsize, GFP_KERNEL);
+ if (!erased_page) {
+ ret = -ENOMEM;
+ goto cleanup;
}
- eccsteps = mtd->writesize/eccsize;
+ memset(erased_page, 0xff, eccsize);
+ bch_encode(engine_conf->bch, erased_page, eccsize,
+ engine_conf->eccmask);
+ kfree(erased_page);
+
+ for (i = 0; i < eccbytes; i++)
+ engine_conf->eccmask[i] ^= 0xff;
- /* Check that we have an oob layout description. */
- if (!mtd->ooblayout) {
- pr_warn("missing oob scheme");
- goto fail;
+ /* Verify that the number of code bytes has the expected value */
+ if (engine_conf->bch->ecc_bytes != eccbytes) {
+ pr_err("Invalid number of ECC bytes: %u, expected: %u\n",
+ eccbytes, engine_conf->bch->ecc_bytes);
+ ret = -EINVAL;
+ goto cleanup;
}
- /* sanity checks */
- if (8*(eccsize+eccbytes) >= (1 << m)) {
- pr_warn("eccsize %u is too large\n", eccsize);
- goto fail;
+ /* Sanity checks */
+ if (8 * (eccsize + eccbytes) >= (1 << m)) {
+ pr_err("ECC step size is too large (%u)\n", eccsize);
+ ret = -EINVAL;
+ goto cleanup;
}
- if (mtd_ooblayout_count_eccbytes(mtd) != (eccsteps*eccbytes)) {
- pr_warn("invalid ecc layout\n");
- goto fail;
+ return 0;
+
+cleanup:
+ nand_ecc_sw_bch_cleanup(nand);
+
+ return ret;
+}
+
+int nand_ecc_sw_bch_init_ctx(struct nand_device *nand)
+{
+ struct nand_ecc_props *conf = &nand->ecc.ctx.conf;
+ struct mtd_info *mtd = nanddev_to_mtd(nand);
+ struct nand_ecc_sw_bch_conf *engine_conf;
+ unsigned int code_size = 0, nsteps;
+ int ret;
+
+ /* 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;
}
- engine_conf->eccmask = kzalloc(eccbytes, GFP_KERNEL);
- engine_conf->errloc = kmalloc_array(t, sizeof(*engine_conf->errloc),
- GFP_KERNEL);
- if (!engine_conf->eccmask || !engine_conf->errloc)
- goto fail;
+ if (!mtd->ooblayout)
+ mtd_set_ooblayout(mtd, nand_get_large_page_ooblayout());
+
+ conf->engine_type = NAND_ECC_ENGINE_TYPE_SOFT;
+ conf->algo = NAND_ECC_ALGO_BCH;
+ conf->step_size = nand->ecc.user_conf.step_size;
+ conf->strength = nand->ecc.user_conf.strength;
/*
- * compute and store the inverted ecc of an erased ecc block
+ * Board driver should supply ECC size and ECC strength
+ * values to select how many bits are correctable.
+ * Otherwise, default to 512 bytes for large page devices and 256 for
+ * small page devices.
*/
- erased_page = kmalloc(eccsize, GFP_KERNEL);
- if (!erased_page)
- goto fail;
+ if (!conf->step_size) {
+ if (mtd->oobsize >= 64)
+ conf->step_size = 512;
+ else
+ conf->step_size = 256;
- memset(erased_page, 0xff, eccsize);
- bch_encode(engine_conf->bch, erased_page, eccsize,
- engine_conf->eccmask);
- kfree(erased_page);
+ conf->strength = 4;
+ }
- for (i = 0; i < eccbytes; i++)
- engine_conf->eccmask[i] ^= 0xff;
+ nsteps = mtd->writesize / conf->step_size;
+
+ /* Maximize */
+ if (nand->ecc.user_conf.flags & NAND_ECC_MAXIMIZE_STRENGTH) {
+ conf->step_size = 1024;
+ nsteps = mtd->writesize / conf->step_size;
+ /* Reserve 2 bytes for the BBM */
+ code_size = (mtd->oobsize - 2) / nsteps;
+ conf->strength = code_size * 8 / fls(8 * conf->step_size);
+ }
+
+ if (!code_size)
+ code_size = DIV_ROUND_UP(conf->strength *
+ fls(8 * conf->step_size), 8);
+
+ if (!conf->strength)
+ conf->strength = (code_size * 8) / fls(8 * conf->step_size);
+
+ if (!code_size && !conf->strength) {
+ pr_err("Missing ECC parameters\n");
+ return -EINVAL;
+ }
+
+ engine_conf = kzalloc(sizeof(*engine_conf), GFP_KERNEL);
+ if (!engine_conf)
+ return -ENOMEM;
+
+ ret = nand_ecc_init_req_tweaking(&engine_conf->req_ctx, nand);
+ if (ret)
+ goto free_engine_conf;
+
+ engine_conf->code_size = code_size;
+ engine_conf->nsteps = nsteps;
+ engine_conf->calc_buf = kzalloc(mtd->oobsize, GFP_KERNEL);
+ engine_conf->code_buf = kzalloc(mtd->oobsize, GFP_KERNEL);
+ if (!engine_conf->calc_buf || !engine_conf->code_buf) {
+ ret = -ENOMEM;
+ goto free_bufs;
+ }
- if (!eccstrength)
- nand->ecc.ctx.conf.strength = (eccbytes * 8) / fls(8 * eccsize);
+ nand->ecc.ctx.priv = engine_conf;
+ nand->ecc.ctx.total = nsteps * code_size;
+
+ ret = nand_ecc_sw_bch_init(nand);
+ if (ret)
+ goto free_bufs;
+
+ /* Verify the layout validity */
+ if (mtd_ooblayout_count_eccbytes(mtd) !=
+ engine_conf->nsteps * engine_conf->code_size) {
+ pr_err("Invalid ECC layout\n");
+ ret = -EINVAL;
+ goto cleanup_bch_ctx;
+ }
return 0;
-fail:
+cleanup_bch_ctx:
nand_ecc_sw_bch_cleanup(nand);
+free_bufs:
+ nand_ecc_cleanup_req_tweaking(&engine_conf->req_ctx);
+ kfree(engine_conf->calc_buf);
+ kfree(engine_conf->code_buf);
+free_engine_conf:
+ kfree(engine_conf);
- return -EINVAL;
+ return ret;
}
-EXPORT_SYMBOL(nand_ecc_sw_bch_init);
+EXPORT_SYMBOL(nand_ecc_sw_bch_init_ctx);
-/**
- * nand_ecc_sw_bch_cleanup - Cleanup software BCH ECC resources
- * @nand: NAND device
- */
-void nand_ecc_sw_bch_cleanup(struct nand_device *nand)
+void nand_ecc_sw_bch_cleanup_ctx(struct nand_device *nand)
{
struct nand_ecc_sw_bch_conf *engine_conf = nand->ecc.ctx.priv;
if (engine_conf) {
- bch_free(engine_conf->bch);
- kfree(engine_conf->errloc);
- kfree(engine_conf->eccmask);
+ nand_ecc_sw_bch_cleanup(nand);
+ nand_ecc_cleanup_req_tweaking(&engine_conf->req_ctx);
+ kfree(engine_conf->calc_buf);
+ kfree(engine_conf->code_buf);
+ kfree(engine_conf);
+ }
+}
+EXPORT_SYMBOL(nand_ecc_sw_bch_cleanup_ctx);
+
+static int nand_ecc_sw_bch_prepare_io_req(struct nand_device *nand,
+ struct nand_page_io_req *req)
+{
+ struct nand_ecc_sw_bch_conf *engine_conf = nand->ecc.ctx.priv;
+ struct mtd_info *mtd = nanddev_to_mtd(nand);
+ int eccsize = nand->ecc.ctx.conf.step_size;
+ int eccbytes = engine_conf->code_size;
+ int eccsteps = engine_conf->nsteps;
+ int total = nand->ecc.ctx.total;
+ u8 *ecccalc = engine_conf->calc_buf;
+ const u8 *data;
+ int i;
+
+ /* Nothing to do for a raw operation */
+ if (req->mode == MTD_OPS_RAW)
+ return 0;
+
+ /* This engine does not provide BBM/free OOB bytes protection */
+ if (!req->datalen)
+ return 0;
+
+ nand_ecc_tweak_req(&engine_conf->req_ctx, req);
+
+ /* No more preparation for page read */
+ if (req->type == NAND_PAGE_READ)
+ return 0;
+
+ /* Preparation for page write: derive the ECC bytes and place them */
+ for (i = 0, data = req->databuf.out;
+ eccsteps;
+ eccsteps--, i += eccbytes, data += eccsize)
+ nand_ecc_sw_bch_calculate(nand, data, &ecccalc[i]);
+
+ return mtd_ooblayout_set_eccbytes(mtd, ecccalc, (void *)req->oobbuf.out,
+ 0, total);
+}
+
+static int nand_ecc_sw_bch_finish_io_req(struct nand_device *nand,
+ struct nand_page_io_req *req)
+{
+ struct nand_ecc_sw_bch_conf *engine_conf = nand->ecc.ctx.priv;
+ struct mtd_info *mtd = nanddev_to_mtd(nand);
+ int eccsize = nand->ecc.ctx.conf.step_size;
+ int total = nand->ecc.ctx.total;
+ int eccbytes = engine_conf->code_size;
+ int eccsteps = engine_conf->nsteps;
+ u8 *ecccalc = engine_conf->calc_buf;
+ u8 *ecccode = engine_conf->code_buf;
+ unsigned int max_bitflips = 0;
+ u8 *data = req->databuf.in;
+ int i, ret;
+
+ /* Nothing to do for a raw operation */
+ if (req->mode == MTD_OPS_RAW)
+ return 0;
+
+ /* This engine does not provide BBM/free OOB bytes protection */
+ if (!req->datalen)
+ return 0;
+
+ /* No more preparation for page write */
+ if (req->type == NAND_PAGE_WRITE) {
+ nand_ecc_restore_req(&engine_conf->req_ctx, req);
+ return 0;
}
+
+ /* Finish a page read: retrieve the (raw) ECC bytes*/
+ ret = mtd_ooblayout_get_eccbytes(mtd, ecccode, req->oobbuf.in, 0,
+ total);
+ if (ret)
+ return ret;
+
+ /* Calculate the ECC bytes */
+ for (i = 0; eccsteps; eccsteps--, i += eccbytes, data += eccsize)
+ nand_ecc_sw_bch_calculate(nand, data, &ecccalc[i]);
+
+ /* Finish a page read: compare and correct */
+ for (eccsteps = engine_conf->nsteps, i = 0, data = req->databuf.in;
+ eccsteps;
+ eccsteps--, i += eccbytes, data += eccsize) {
+ int stat = nand_ecc_sw_bch_correct(nand, data,
+ &ecccode[i],
+ &ecccalc[i]);
+ if (stat < 0) {
+ mtd->ecc_stats.failed++;
+ } else {
+ mtd->ecc_stats.corrected += stat;
+ max_bitflips = max_t(unsigned int, max_bitflips, stat);
+ }
+ }
+
+ nand_ecc_restore_req(&engine_conf->req_ctx, req);
+
+ return max_bitflips;
+}
+
+static struct nand_ecc_engine_ops nand_ecc_sw_bch_engine_ops = {
+ .init_ctx = nand_ecc_sw_bch_init_ctx,
+ .cleanup_ctx = nand_ecc_sw_bch_cleanup_ctx,
+ .prepare_io_req = nand_ecc_sw_bch_prepare_io_req,
+ .finish_io_req = nand_ecc_sw_bch_finish_io_req,
+};
+
+static struct nand_ecc_engine nand_ecc_sw_bch_engine = {
+ .ops = &nand_ecc_sw_bch_engine_ops,
+};
+
+struct nand_ecc_engine *nand_ecc_sw_bch_get_engine(void)
+{
+ return &nand_ecc_sw_bch_engine;
}
-EXPORT_SYMBOL(nand_ecc_sw_bch_cleanup);
+EXPORT_SYMBOL(nand_ecc_sw_bch_get_engine);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ivan Djelic <ivan.djelic@parrot.com>");
base->ecc.user_conf.step_size = chip->ecc.size;
base->ecc.user_conf.strength = chip->ecc.strength;
- engine_conf = kzalloc(sizeof(*engine_conf), GFP_KERNEL);
- if (!engine_conf)
- return -ENOMEM;
-
- engine_conf->code_size = chip->ecc.bytes;
-
- base->ecc.ctx.priv = engine_conf;
-
- ret = nand_ecc_sw_bch_init(base);
+ ret = nand_ecc_sw_bch_init_ctx(base);
if (ret)
- kfree(base->ecc.ctx.priv);
+ return ret;
+
+ engine_conf = base->ecc.ctx.priv;
chip->ecc.size = base->ecc.ctx.conf.step_size;
chip->ecc.strength = base->ecc.ctx.conf.strength;
chip->ecc.steps = engine_conf->nsteps;
chip->ecc.bytes = engine_conf->code_size;
- return ret;
+ return 0;
}
EXPORT_SYMBOL(rawnand_sw_bch_init);
{
struct nand_device *base = &chip->base;
- nand_ecc_sw_bch_cleanup(base);
-
- kfree(base->ecc.ctx.priv);
+ nand_ecc_sw_bch_cleanup_ctx(base);
}
EXPORT_SYMBOL(rawnand_sw_bch_cleanup);
ecc->read_oob = nand_read_oob_std;
ecc->write_oob = nand_write_oob_std;
- /*
- * Board driver should supply ecc.size and ecc.strength
- * values to select how many bits are correctable.
- * Otherwise, default to 4 bits for large page devices.
- */
- if (!ecc->size && (mtd->oobsize >= 64)) {
- ecc->size = 512;
- ecc->strength = 4;
- }
-
- /*
- * if no ecc placement scheme was provided pickup the default
- * large page one.
- */
- if (!mtd->ooblayout) {
- /* handle large page devices only */
- if (mtd->oobsize < 64) {
- WARN(1, "OOB layout is required when using software BCH on small pages\n");
- return -EINVAL;
- }
-
- mtd_set_ooblayout(mtd, nand_get_large_page_ooblayout());
-
- }
-
/*
* We can only maximize ECC config when the default layout is
* used, otherwise we don't know how many bytes can really be
* used.
*/
- if (mtd->ooblayout == nand_get_large_page_ooblayout() &&
- nanddev->ecc.user_conf.flags & NAND_ECC_MAXIMIZE_STRENGTH) {
- int steps, bytes;
-
- /* Always prefer 1k blocks over 512bytes ones */
- ecc->size = 1024;
- steps = mtd->writesize / ecc->size;
+ if (nanddev->ecc.user_conf.flags & NAND_ECC_MAXIMIZE_STRENGTH &&
+ mtd->ooblayout != nand_get_large_page_ooblayout())
+ nanddev->ecc.user_conf.flags &= ~NAND_ECC_MAXIMIZE_STRENGTH;
- /* Reserve 2 bytes for the BBM */
- bytes = (mtd->oobsize - 2) / steps;
- ecc->strength = bytes * 8 / fls(8 * ecc->size);
- }
-
- /* See the software BCH ECC initialization for details */
- ecc->bytes = 0;
ret = rawnand_sw_bch_init(chip);
if (ret) {
WARN(1, "BCH ECC initialization failed!\n");
projects / linux-2.6-microblaze.git / commitdiff