[RESEND PATCH v3 10/20] mtd: spi-nor: Rework the SPI NOR lock/unlock logic

Tudor.Ambarus
2019-08-26T12:09:09Z

From: Boris Brezillon <boris.brezillon@bootlin.com>

Add the SNOR_F_HAS_LOCK flag and set it when SPI_NOR_HAS_LOCK is set
in the flash_info entry or when it's a Micron or ST flash.

Move the locking hooks in a separate struct so that we have just
one field to update when we change the locking implementation.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
[tudor.ambarus@microchip.com: use ->default_init() hook, introduce
spi_nor_late_init_params(), set ops in nor->params]
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
v3: no changes, clear_sr_bp() is handled in the last patch of the
series.

drivers/mtd/spi-nor/spi-nor.c | 50 ++++++++++++++++++++++++++++++++-----------
include/linux/mtd/spi-nor.h | 23 ++++++++++++++------
2 files changed, 53 insertions(+), 20 deletions(-)

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index 235e82a121a1..3f997797fa9d 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -1598,6 +1598,12 @@ static int stm_is_locked(struct spi_nor *nor, loff_t ofs, uint64_t len)
return stm_is_locked_sr(nor, ofs, len, status);
}

+static const struct spi_nor_locking_ops stm_locking_ops = {
+ .lock = stm_lock,
+ .unlock = stm_unlock,
+ .is_locked = stm_is_locked,
+};
+
static int spi_nor_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
{
struct spi_nor *nor = mtd_to_spi_nor(mtd);
@@ -1607,7 +1613,7 @@ static int spi_nor_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
if (ret)
return ret;

- ret = nor->flash_lock(nor, ofs, len);
+ ret = nor->params.locking_ops->lock(nor, ofs, len);

spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_UNLOCK);
return ret;
@@ -1622,7 +1628,7 @@ static int spi_nor_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
if (ret)
return ret;

- ret = nor->flash_unlock(nor, ofs, len);
+ ret = nor->params.locking_ops->unlock(nor, ofs, len);

spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_LOCK);
return ret;
@@ -1637,7 +1643,7 @@ static int spi_nor_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
if (ret)
return ret;

- ret = nor->flash_is_locked(nor, ofs, len);
+ ret = nor->params.locking_ops->is_locked(nor, ofs, len);

spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_LOCK);
return ret;
@@ -4148,6 +4154,7 @@ static void macronix_set_default_init(struct spi_nor *nor)

static void st_micron_set_default_init(struct spi_nor *nor)
{
+ nor->flags = SNOR_F_HAS_LOCK;
nor->params.quad_enable = NULL;
nor->params.set_4byte = st_micron_set_4byte;
}
@@ -4292,6 +4299,23 @@ static void spi_nor_info_init_params(struct spi_nor *nor)
}

/**
+ * spi_nor_late_init_params() - Late initialization of default flash parameters.
+ * @nor: pointer to a 'struct spi_nor'
+ *
+ * Used to set default flash parameters and settings when the ->default_init()
+ * hook or the SFDP parser let voids.
+ */
+static void spi_nor_late_init_params(struct spi_nor *nor)
+{
+ /*
+ * NOR protection support. When locking_ops are not provided, we pick
+ * the default ones.
+ */
+ if (nor->flags & SNOR_F_HAS_LOCK && !nor->params.locking_ops)
+ nor->params.locking_ops = &stm_locking_ops;
+}
+
+/**
* spi_nor_init_params() - Initialize the flash's parameters and settings.
* @nor: pointer to a 'struct spi-nor'.
*
@@ -4316,6 +4340,10 @@ static void spi_nor_info_init_params(struct spi_nor *nor)
* Please not that there is a ->post_bfpt() fixup hook that can overwrite the
* flash parameters and settings imediately after parsing the Basic Flash
* Parameter Table.
+ *
+ * 4/ Late default flash parameters initialization, used when the
+ * ->default_init() hook or the SFDP parser do not set specific params.
+ * spi_nor_late_init_params()
*/
static void spi_nor_init_params(struct spi_nor *nor)
{
@@ -4326,6 +4354,8 @@ static void spi_nor_init_params(struct spi_nor *nor)
if ((nor->info->flags & (SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ)) &&
!(nor->info->flags & SPI_NOR_SKIP_SFDP))
spi_nor_sfdp_init_params(nor);
+
+ spi_nor_late_init_params(nor);
}

static int spi_nor_select_read(struct spi_nor *nor,
@@ -4707,6 +4737,9 @@ int spi_nor_scan(struct spi_nor *nor, const char *name,
if (info->flags & SPI_S3AN)
nor->flags |= SNOR_F_READY_XSR_RDY;

+ if (info->flags & SPI_NOR_HAS_LOCK)
+ nor->flags |= SNOR_F_HAS_LOCK;
+
/*
* Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up
* with the software protection bits set.
@@ -4731,16 +4764,7 @@ int spi_nor_scan(struct spi_nor *nor, const char *name,
mtd->_read = spi_nor_read;
mtd->_resume = spi_nor_resume;

- /* NOR protection support for STmicro/Micron chips and similar */
- if (JEDEC_MFR(info) == SNOR_MFR_ST ||
- JEDEC_MFR(info) == SNOR_MFR_MICRON ||
- info->flags & SPI_NOR_HAS_LOCK) {
- nor->flash_lock = stm_lock;
- nor->flash_unlock = stm_unlock;
- nor->flash_is_locked = stm_is_locked;
- }
-
- if (nor->flash_lock && nor->flash_unlock && nor->flash_is_locked) {
+ if (nor->params.locking_ops) {
mtd->_lock = spi_nor_lock;
mtd->_unlock = spi_nor_unlock;
mtd->_is_locked = spi_nor_is_locked;
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index 7da89dd483cb..ea3bcac54dc2 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -243,6 +243,7 @@ enum spi_nor_option_flags {
SNOR_F_BROKEN_RESET = BIT(6),
SNOR_F_4B_OPCODES = BIT(7),
SNOR_F_HAS_4BAIT = BIT(8),
+ SNOR_F_HAS_LOCK = BIT(9),
};

/**
@@ -466,6 +467,18 @@ enum spi_nor_pp_command_index {
struct spi_nor;

/**
+ * struct spi_nor_locking_ops - SPI NOR locking methods
+ * @lock: lock a region of the SPI NOR.
+ * @unlock: unlock a region of the SPI NOR.
+ * @is_locked: check if a region of the SPI NOR is completely locked
+ */
+struct spi_nor_locking_ops {
+ int (*lock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
+ int (*unlock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
+ int (*is_locked)(struct spi_nor *nor, loff_t ofs, uint64_t len);
+};
+
+/**
* struct spi_nor_flash_parameter - SPI NOR flash parameters and settings.
* Includes legacy flash parameters and settings that can be overwritten
* by the spi_nor_fixups hooks, or dynamically when parsing the JESD216
@@ -483,6 +496,7 @@ struct spi_nor;
* Table.
* @quad_enable: enables SPI NOR quad mode.
* @set_4byte: puts the SPI NOR in 4 byte addressing mode.
+ * @locking_ops: SPI NOR locking methods.
*/
struct spi_nor_flash_parameter {
u64 size;
@@ -496,6 +510,8 @@ struct spi_nor_flash_parameter {

int (*quad_enable)(struct spi_nor *nor);
int (*set_4byte)(struct spi_nor *nor, bool enable);
+
+ const struct spi_nor_locking_ops *locking_ops;
};

/**
@@ -536,10 +552,6 @@ struct flash_info;
* @erase: [DRIVER-SPECIFIC] erase a sector of the SPI NOR
* at the offset @offs; if not provided by the driver,
* spi-nor will send the erase opcode via write_reg()
- * @flash_lock: [FLASH-SPECIFIC] lock a region of the SPI NOR
- * @flash_unlock: [FLASH-SPECIFIC] unlock a region of the SPI NOR
- * @flash_is_locked: [FLASH-SPECIFIC] check if a region of the SPI NOR is
- * completely locked
* @clear_sr_bp: [FLASH-SPECIFIC] clears the Block Protection Bits from
* the SPI NOR Status Register.
* @params: [FLASH-SPECIFIC] SPI-NOR flash parameters and settings.
@@ -579,9 +591,6 @@ struct spi_nor {
size_t len, const u_char *write_buf);
int (*erase)(struct spi_nor *nor, loff_t offs);

- int (*flash_lock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
- int (*flash_unlock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
- int (*flash_is_locked)(struct spi_nor *nor, loff_t ofs, uint64_t len);
int (*clear_sr_bp)(struct spi_nor *nor);
struct spi_nor_flash_parameter params;

--
2.9.5