[PATCH v6 08/21] mtd: spi-nor-core: Introduce flash-specific fixup hooks
Pratyush Yadav
p.yadav at ti.com
Fri Jun 5 14:44:47 CEST 2020
Sometimes the information in a flash's SFDP tables is wrong. Sometimes
some information just can't be expressed in the SFDP table. So,
introduce the fixup hooks to allow tailoring settings for a specific
flash.
Three hooks are added: default_init, post_sfdp, and post_bfpt. These
allow tweaking the flash settings at different point in the probe
sequence. Since the hooks reside in nor->info, set that value just
before the call to spi_nor_init_params().
The hooks and at what points they are executed mimics Linux's spi-nor
framework. One major difference is that Linux puts the struct
spi_nor_fixups in nor->info. This is not possible in U-Boot because the
spi-nor-ids list is shared between spi-nor-core.c and spi-nor-tiny.c.
Since spi-nor-tiny shouldn't have those fixup hooks populated, add a
separate function that lets flashes populate their fixup hooks.
Signed-off-by: Pratyush Yadav <p.yadav at ti.com>
---
drivers/mtd/spi/spi-nor-core.c | 78 ++++++++++++++++++++++++++++++++--
include/linux/mtd/spi-nor.h | 2 +
2 files changed, 77 insertions(+), 3 deletions(-)
diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c
index 28f5f877b4..2494c2e724 100644
--- a/drivers/mtd/spi/spi-nor-core.c
+++ b/drivers/mtd/spi/spi-nor-core.c
@@ -150,6 +150,31 @@ struct sfdp_bfpt {
u32 dwords[BFPT_DWORD_MAX];
};
+/**
+ * struct spi_nor_fixups - SPI NOR fixup hooks
+ * @default_init: called after default flash parameters init. Used to tweak
+ * flash parameters when information provided by the flash_info
+ * table is incomplete or wrong.
+ * @post_bfpt: called after the BFPT table has been parsed
+ * @post_sfdp: called after SFDP has been parsed (is also called for SPI NORs
+ * that do not support RDSFDP). Typically used to tweak various
+ * parameters that could not be extracted by other means (i.e.
+ * when information provided by the SFDP/flash_info tables are
+ * incomplete or wrong).
+ *
+ * Those hooks can be used to tweak the SPI NOR configuration when the SFDP
+ * table is broken or not available.
+ */
+struct spi_nor_fixups {
+ void (*default_init)(struct spi_nor *nor);
+ int (*post_bfpt)(struct spi_nor *nor,
+ const struct sfdp_parameter_header *bfpt_header,
+ const struct sfdp_bfpt *bfpt,
+ struct spi_nor_flash_parameter *params);
+ void (*post_sfdp)(struct spi_nor *nor,
+ struct spi_nor_flash_parameter *params);
+};
+
static int spi_nor_read_write_reg(struct spi_nor *nor, struct spi_mem_op
*op, void *buf)
{
@@ -1747,6 +1772,18 @@ static const struct sfdp_bfpt_erase sfdp_bfpt_erases[] = {
static int spi_nor_hwcaps_read2cmd(u32 hwcaps);
+static int
+spi_nor_post_bfpt_fixups(struct spi_nor *nor,
+ const struct sfdp_parameter_header *bfpt_header,
+ const struct sfdp_bfpt *bfpt,
+ struct spi_nor_flash_parameter *params)
+{
+ if (nor->fixups && nor->fixups->post_bfpt)
+ return nor->fixups->post_bfpt(nor, bfpt_header, bfpt, params);
+
+ return 0;
+}
+
/**
* spi_nor_parse_bfpt() - read and parse the Basic Flash Parameter Table.
* @nor: pointer to a 'struct spi_nor'
@@ -1885,7 +1922,8 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
/* Stop here if not JESD216 rev A or later. */
if (bfpt_header->length < BFPT_DWORD_MAX)
- return 0;
+ return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt,
+ params);
/* Page size: this field specifies 'N' so the page size = 2^N bytes. */
params->page_size = bfpt.dwords[BFPT_DWORD(11)];
@@ -1918,7 +1956,7 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
return -EINVAL;
}
- return 0;
+ return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt, params);
}
/**
@@ -2081,6 +2119,29 @@ static int spi_nor_parse_sfdp(struct spi_nor *nor,
}
#endif /* SPI_FLASH_SFDP_SUPPORT */
+/**
+ * spi_nor_post_sfdp_fixups() - Updates the flash's parameters and settings
+ * after SFDP has been parsed (is also called for SPI NORs that do not
+ * support RDSFDP).
+ * @nor: pointer to a 'struct spi_nor'
+ *
+ * Typically used to tweak various parameters that could not be extracted by
+ * other means (i.e. when information provided by the SFDP/flash_info tables
+ * are incomplete or wrong).
+ */
+static void spi_nor_post_sfdp_fixups(struct spi_nor *nor,
+ struct spi_nor_flash_parameter *params)
+{
+ if (nor->fixups && nor->fixups->post_sfdp)
+ nor->fixups->post_sfdp(nor, params);
+}
+
+static void spi_nor_default_init_fixups(struct spi_nor *nor)
+{
+ if (nor->fixups && nor->fixups->default_init)
+ nor->fixups->default_init(nor);
+}
+
static int spi_nor_init_params(struct spi_nor *nor,
const struct flash_info *info,
struct spi_nor_flash_parameter *params)
@@ -2159,6 +2220,8 @@ static int spi_nor_init_params(struct spi_nor *nor,
}
}
+ spi_nor_default_init_fixups(nor);
+
/* Override the parameters with data read from SFDP tables. */
nor->addr_width = 0;
nor->mtd.erasesize = 0;
@@ -2175,6 +2238,8 @@ static int spi_nor_init_params(struct spi_nor *nor,
}
}
+ spi_nor_post_sfdp_fixups(nor, params);
+
return 0;
}
@@ -2422,6 +2487,10 @@ static int spi_nor_init(struct spi_nor *nor)
return 0;
}
+void spi_nor_set_fixups(struct spi_nor *nor)
+{
+}
+
int spi_nor_scan(struct spi_nor *nor)
{
struct spi_nor_flash_parameter params;
@@ -2470,6 +2539,10 @@ int spi_nor_scan(struct spi_nor *nor)
info = spi_nor_read_id(nor);
if (IS_ERR_OR_NULL(info))
return -ENOENT;
+ nor->info = info;
+
+ spi_nor_set_fixups(nor);
+
/* Parse the Serial Flash Discoverable Parameters table. */
ret = spi_nor_init_params(nor, info, ¶ms);
if (ret)
@@ -2569,7 +2642,6 @@ int spi_nor_scan(struct spi_nor *nor)
}
/* Send all the required SPI flash commands to initialize device */
- nor->info = info;
ret = spi_nor_init(nor);
if (ret)
return ret;
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index 922e795ea6..5842e9d6ee 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -414,6 +414,7 @@ struct flash_info;
* @write_proto: the SPI protocol for write operations
* @reg_proto the SPI protocol for read_reg/write_reg/erase operations
* @cmd_buf: used by the write_reg
+ * @fixups: flash-specific fixup hooks.
* @prepare: [OPTIONAL] do some preparations for the
* read/write/erase/lock/unlock operations
* @unprepare: [OPTIONAL] do some post work after the
@@ -455,6 +456,7 @@ struct spi_nor {
bool sst_write_second;
u32 flags;
u8 cmd_buf[SPI_NOR_MAX_CMD_SIZE];
+ struct spi_nor_fixups *fixups;
int (*setup)(struct spi_nor *nor, const struct flash_info *info,
const struct spi_nor_flash_parameter *params,
--
2.27.0
More information about the U-Boot
mailing list