diff mbox series

[v3,12/25] mtd: spi-nor: core: Call spi_nor_post_sfdp_fixups() only when SFDP is defined

Message ID 20211029172633.886453-13-tudor.ambarus@microchip.com (mailing list archive)
State New, archived
Headers show
Series mtd: spi-nor: Clean params init | expand

Commit Message

Tudor Ambarus Oct. 29, 2021, 5:26 p.m. UTC 
spi_nor_post_sfdp_fixups() was called even when there were no SFDP
tables defined. late_init() should be instead used for flashes that
do not define SFDP tables.

Use spi_nor_post_sfdp_fixups() just to fix SFDP data. post_sfdp()
hook is as of now used just by s28hs512t, mt35xu512aba, and both
support SFDP, there's no functional change with this patch.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 drivers/mtd/spi-nor/core.c | 56 ++++++++++++++++++--------------------
 1 file changed, 26 insertions(+), 30 deletions(-)

Comments

Michael Walle Nov. 9, 2021, 10:18 a.m. UTC | #1 
Am 2021-10-29 19:26, schrieb Tudor Ambarus:
> spi_nor_post_sfdp_fixups() was called even when there were no SFDP
> tables defined. late_init() should be instead used for flashes that
> do not define SFDP tables.
> 
> Use spi_nor_post_sfdp_fixups() just to fix SFDP data. post_sfdp()
> hook is as of now used just by s28hs512t, mt35xu512aba, and both
> support SFDP, there's no functional change with this patch.
> 
> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
> ---
>  drivers/mtd/spi-nor/core.c | 56 ++++++++++++++++++--------------------
>  1 file changed, 26 insertions(+), 30 deletions(-)
> 
> diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
> index 4679298c5301..82cc56c9d09e 100644
> --- a/drivers/mtd/spi-nor/core.c
> +++ b/drivers/mtd/spi-nor/core.c
> @@ -2508,6 +2508,25 @@ static void
> spi_nor_manufacturer_init_params(struct spi_nor *nor)
>  		nor->info->fixups->default_init(nor);
>  }
> 
> +/**
> + * spi_nor_post_sfdp_fixups() - Updates the flash's parameters and 
> settings
> + * after SFDP has been parsed. Called only for flashes that define 
> JESD216 SFDP
> + * tables.
> + * @nor:	pointer to a 'struct spi_nor'
> + *
> + * Used to tweak various flash parameters when information provided by 
> the SFDP
> + * tables are wrong.
> + */
> +static void spi_nor_post_sfdp_fixups(struct spi_nor *nor)
> +{
> +	if (nor->manufacturer && nor->manufacturer->fixups &&
> +	    nor->manufacturer->fixups->post_sfdp)
> +		nor->manufacturer->fixups->post_sfdp(nor);
> +
> +	if (nor->info->fixups && nor->info->fixups->post_sfdp)
> +		nor->info->fixups->post_sfdp(nor);
> +}
> +
>  /**
>   * spi_nor_sfdp_init_params() - Initialize the flash's parameters and 
> settings
>   * based on JESD216 SFDP standard.
> @@ -2522,7 +2541,9 @@ static void spi_nor_sfdp_init_params(struct 
> spi_nor *nor)
> 
>  	memcpy(&sfdp_params, nor->params, sizeof(sfdp_params));
> 
> -	if (spi_nor_parse_sfdp(nor)) {
> +	if (!spi_nor_parse_sfdp(nor)) {
> +		spi_nor_post_sfdp_fixups(nor);

I find this function particulary confusing. Why is it
copying the params around? I know the function doc
says rollback, but can't we make this better?

Either make spi_nor_parse_sfdp() commit the nor->params update
atomically, or pass a second parameter sfdp_params, which are
copied to nor->params here if spi_nor_parse_sfdp() was successful.

Also the control flow could be better.

ret = spi_nor_parse_sfdp(nor, &sfdp_params);
if (!ret) {
     /* clever comment, why is addr_width = 0 here */
     nor->addr_width = 0;
     nor->flags &= ~SNOR_F_4B_OPCODES;
     return 0;
}

memcpy(nor->params, &sfdp_params, sizeof(*nor->params));
spi_nor_post_sfdp_fixups(nor);

Having an even closer look, addr_width is set to 0 because
spi_nor_parse_sfdp() is also changing that. nor->flags
is also changed and not only the SNOR_F_4B_OPCODES bit. But
only that one is cleared?!

I think this deserves another cleanup series. Having the
rollback here makes no sense. You'd have to keep both in
sync.

IMHO best would be a second parameter and make sure all
code in sfdp.c don't change anything else. Which would
probably mean that addr_width and flags will move to
nor->params.

Anyway, for now:
Reviewed-by: Michael Walle <michael@walle.cc>

-michael
diff mbox series

Patch

diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index 4679298c5301..82cc56c9d09e 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -2508,6 +2508,25 @@  static void spi_nor_manufacturer_init_params(struct spi_nor *nor)
 		nor->info->fixups->default_init(nor);
 }
 
+/**
+ * spi_nor_post_sfdp_fixups() - Updates the flash's parameters and settings
+ * after SFDP has been parsed. Called only for flashes that define JESD216 SFDP
+ * tables.
+ * @nor:	pointer to a 'struct spi_nor'
+ *
+ * Used to tweak various flash parameters when information provided by the SFDP
+ * tables are wrong.
+ */
+static void spi_nor_post_sfdp_fixups(struct spi_nor *nor)
+{
+	if (nor->manufacturer && nor->manufacturer->fixups &&
+	    nor->manufacturer->fixups->post_sfdp)
+		nor->manufacturer->fixups->post_sfdp(nor);
+
+	if (nor->info->fixups && nor->info->fixups->post_sfdp)
+		nor->info->fixups->post_sfdp(nor);
+}
+
 /**
  * spi_nor_sfdp_init_params() - Initialize the flash's parameters and settings
  * based on JESD216 SFDP standard.
@@ -2522,7 +2541,9 @@  static void spi_nor_sfdp_init_params(struct spi_nor *nor)
 
 	memcpy(&sfdp_params, nor->params, sizeof(sfdp_params));
 
-	if (spi_nor_parse_sfdp(nor)) {
+	if (!spi_nor_parse_sfdp(nor)) {
+		spi_nor_post_sfdp_fixups(nor);
+	} else {
 		memcpy(nor->params, &sfdp_params, sizeof(*nor->params));
 		nor->addr_width = 0;
 		nor->flags &= ~SNOR_F_4B_OPCODES;
@@ -2642,26 +2663,6 @@  static void spi_nor_info_init_params(struct spi_nor *nor)
 	spi_nor_init_uniform_erase_map(map, erase_mask, params->size);
 }
 
-/**
- * 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)
-{
-	if (nor->manufacturer && nor->manufacturer->fixups &&
-	    nor->manufacturer->fixups->post_sfdp)
-		nor->manufacturer->fixups->post_sfdp(nor);
-
-	if (nor->info->fixups && nor->info->fixups->post_sfdp)
-		nor->info->fixups->post_sfdp(nor);
-}
-
 /**
  * spi_nor_late_init_params() - Late initialization of default flash parameters.
  * @nor:	pointer to a 'struct spi_nor'
@@ -2712,15 +2713,12 @@  static void spi_nor_late_init_params(struct spi_nor *nor)
  *    Please note that there is a ->post_bfpt() fixup hook that can overwrite
  *    the flash parameters and settings immediately after parsing the Basic
  *    Flash Parameter Table.
+ *    spi_nor_post_sfdp_fixups() is called after the SFDP tables are parsed.
+ *    It is used to tweak various flash parameters when information provided
+ *    by the SFDP tables are wrong.
  *
  * which can be overwritten by:
- * 4/ Post SFDP flash parameters initialization. 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).
- *		spi_nor_post_sfdp_fixups()
- *
- * 5/ Late flash parameters initialization, used to initialize flash
+ * 4/ Late flash parameters initialization, used to initialize flash
  * parameters that are not declared in the JESD216 SFDP standard, or where SFDP
  * tables are not defined at all.
  *		spi_nor_late_init_params()
@@ -2740,8 +2738,6 @@  static int spi_nor_init_params(struct spi_nor *nor)
 	    !(nor->info->flags & SPI_NOR_SKIP_SFDP))
 		spi_nor_sfdp_init_params(nor);
 
-	spi_nor_post_sfdp_fixups(nor);
-
 	spi_nor_late_init_params(nor);
 
 	return 0;