--- /dev/null
+From 773bbe10449731c9525457873e0c2342e5cf883b Mon Sep 17 00:00:00 2001
+From: Michael Walle <michael@walle.cc>
+Date: Thu, 11 Aug 2022 00:06:53 +0200
+Subject: [PATCH] mtd: spi-nor: add generic flash driver
+
+Our SFDP parsing is everything we need to support all basic operations
+of a flash device. If the flash isn't found in our in-kernel flash
+database, gracefully fall back to a driver described solely by its SFDP
+tables.
+
+Signed-off-by: Michael Walle <michael@walle.cc>
+Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
+Tested-by: Tudor Ambarus <tudor.ambarus@microchip.com>
+Reviewed-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
+Link: https://lore.kernel.org/r/20220810220654.1297699-7-michael@walle.cc
+---
+ drivers/mtd/spi-nor/core.c | 26 ++++++++++++++++++++++++--
+ drivers/mtd/spi-nor/core.h | 1 +
+ drivers/mtd/spi-nor/sfdp.c | 27 +++++++++++++++++++++++++++
+ 3 files changed, 52 insertions(+), 2 deletions(-)
+
+--- a/drivers/mtd/spi-nor/core.c
++++ b/drivers/mtd/spi-nor/core.c
+@@ -1636,6 +1636,16 @@ static const struct spi_nor_manufacturer
+ &spi_nor_xmc,
+ };
+
++static const struct flash_info spi_nor_generic_flash = {
++ .name = "spi-nor-generic",
++ /*
++ * JESD216 rev A doesn't specify the page size, therefore we need a
++ * sane default.
++ */
++ .page_size = 256,
++ .parse_sfdp = true,
++};
++
+ static const struct flash_info *spi_nor_match_id(struct spi_nor *nor,
+ const u8 *id)
+ {
+@@ -1669,6 +1679,14 @@ static const struct flash_info *spi_nor_
+ }
+
+ info = spi_nor_match_id(nor, id);
++
++ /* Fallback to a generic flash described only by its SFDP data. */
++ if (!info) {
++ ret = spi_nor_check_sfdp_signature(nor);
++ if (!ret)
++ info = &spi_nor_generic_flash;
++ }
++
+ if (!info) {
+ dev_err(nor->dev, "unrecognized JEDEC id bytes: %*ph\n",
+ SPI_NOR_MAX_ID_LEN, id);
+@@ -2105,8 +2123,12 @@ static int spi_nor_select_pp(struct spi_
+ * spi_nor_select_uniform_erase() - select optimum uniform erase type
+ * @map: the erase map of the SPI NOR
+ * @wanted_size: the erase type size to search for. Contains the value of
+- * info->sector_size or of the "small sector" size in case
+- * CONFIG_MTD_SPI_NOR_USE_4K_SECTORS is defined.
++ * info->sector_size, the "small sector" size in case
++ * CONFIG_MTD_SPI_NOR_USE_4K_SECTORS is defined or 0 if
++ * there is no information about the sector size. The
++ * latter is the case if the flash parameters are parsed
++ * solely by SFDP, then the largest supported erase type
++ * is selected.
+ *
+ * Once the optimum uniform sector erase command is found, disable all the
+ * other.
+--- a/drivers/mtd/spi-nor/core.h
++++ b/drivers/mtd/spi-nor/core.h
+@@ -708,6 +708,8 @@ int spi_nor_controller_ops_read_reg(stru
+ int spi_nor_controller_ops_write_reg(struct spi_nor *nor, u8 opcode,
+ const u8 *buf, size_t len);
+
++int spi_nor_check_sfdp_signature(struct spi_nor *nor);
++
+ static inline struct spi_nor *mtd_to_spi_nor(struct mtd_info *mtd)
+ {
+ return container_of(mtd, struct spi_nor, mtd);
+--- a/drivers/mtd/spi-nor/sfdp.c
++++ b/drivers/mtd/spi-nor/sfdp.c
+@@ -1250,6 +1250,33 @@ static void spi_nor_post_sfdp_fixups(str
+ }
+
+ /**
++ * spi_nor_check_sfdp_signature() - check for a valid SFDP signature
++ * @nor: pointer to a 'struct spi_nor'
++ *
++ * Used to detect if the flash supports the RDSFDP command as well as the
++ * presence of a valid SFDP table.
++ *
++ * Return: 0 on success, -errno otherwise.
++ */
++int spi_nor_check_sfdp_signature(struct spi_nor *nor)
++{
++ u32 signature;
++ int err;
++
++ /* Get the SFDP header. */
++ err = spi_nor_read_sfdp_dma_unsafe(nor, 0, sizeof(signature),
++ &signature);
++ if (err < 0)
++ return err;
++
++ /* Check the SFDP signature. */
++ if (le32_to_cpu(signature) != SFDP_SIGNATURE)
++ return -EINVAL;
++
++ return 0;
++}
++
++/**
+ * spi_nor_parse_sfdp() - parse the Serial Flash Discoverable Parameters.
+ * @nor: pointer to a 'struct spi_nor'
+ *
return !!nor->params->erase_map.uniform_erase_type;
}
-@@ -2158,6 +2160,7 @@ static int spi_nor_select_erase(struct s
+@@ -2180,6 +2182,7 @@ static int spi_nor_select_erase(struct s
{
struct spi_nor_erase_map *map = &nor->params->erase_map;
const struct spi_nor_erase_type *erase = NULL;
struct mtd_info *mtd = &nor->mtd;
u32 wanted_size = nor->info->sector_size;
int i;
-@@ -2190,8 +2193,9 @@ static int spi_nor_select_erase(struct s
+@@ -2212,8 +2215,9 @@ static int spi_nor_select_erase(struct s
*/
for (i = SNOR_ERASE_TYPE_MAX - 1; i >= 0; i--) {
if (map->erase_type[i].size) {
}
}
-@@ -2199,6 +2203,9 @@ static int spi_nor_select_erase(struct s
+@@ -2221,6 +2225,9 @@ static int spi_nor_select_erase(struct s
return -EINVAL;
mtd->erasesize = erase->size;
projects / openwrt / staging / neocturne.git / commitdiff