[U-Boot] [PATCH 24/25] sf: Add a method to obtain the block-protect setting

Simon Glass
2018-11-06T22:21:41Z

It is useful to obtain the block-protect setting of the SPI flash, so we
know whether it is fully open or (perhaps partially) write-protected. Add
a method for this. Update the sandbox driver to process this operation and
add a test.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

arch/sandbox/include/asm/test.h | 8 ++++++++
drivers/mtd/spi/sandbox.c | 10 ++++++++++
drivers/mtd/spi/sf-uclass.c | 9 +++++++++
drivers/mtd/spi/sf_internal.h | 3 +++
drivers/mtd/spi/sf_probe.c | 8 ++++++++
drivers/mtd/spi/spi_flash.c | 12 ++++++++++++
include/spi_flash.h | 27 +++++++++++++++++++++++++++
test/dm/sf.c | 9 +++++++++
8 files changed, 86 insertions(+)

diff --git a/arch/sandbox/include/asm/test.h b/arch/sandbox/include/asm/test.h
index 8e60f80ae7f..5e818392959 100644
--- a/arch/sandbox/include/asm/test.h
+++ b/arch/sandbox/include/asm/test.h
@@ -113,4 +113,12 @@ int sandbox_osd_get_mem(struct udevice *dev, u8 *buf, size_t buflen);
int sandbox_pwm_get_config(struct udevice *dev, uint channel, uint *period_nsp,
uint *duty_nsp, bool *enablep, bool *polarityp);

+/**
+ * sandbox_sf_set_block_protect() - Set the BP bits of the status register
+ *
+ * @dev: Device to update
+ * @bp_mask: BP bits to set (bits 2:0, so a value of 0 to 7)
+ */
+void sandbox_sf_set_block_protect(struct udevice *dev, int bp_mask);
+
#endif
diff --git a/drivers/mtd/spi/sandbox.c b/drivers/mtd/spi/sandbox.c
index 7fef754c634..7b9891cb981 100644
--- a/drivers/mtd/spi/sandbox.c
+++ b/drivers/mtd/spi/sandbox.c
@@ -57,6 +57,8 @@ static const char *sandbox_sf_state_name(enum sandbox_sf_state state)
/* Bits for the status register */
#define STAT_WIP (1 << 0)
#define STAT_WEL (1 << 1)
+#define STAT_BP_SHIFT 2
+#define STAT_BP_MASK (7 << STAT_BP_SHIFT)

/* Assume all SPI flashes have 3 byte addresses since they do atm */
#define SF_ADDR_LEN 3
@@ -102,6 +104,14 @@ struct sandbox_spi_flash_plat_data {
int cs;
};

+void sandbox_sf_set_block_protect(struct udevice *dev, int bp_mask)
+{
+ struct sandbox_spi_flash *sbsf = dev_get_priv(dev);
+
+ sbsf->status &= ~STAT_BP_MASK;
+ sbsf->status |= bp_mask << STAT_BP_SHIFT;
+}
+
/**
* This is a very strange probe function. If it has platform data (which may
* have come from the device tree) then this function gets the filename and
diff --git a/drivers/mtd/spi/sf-uclass.c b/drivers/mtd/spi/sf-uclass.c
index 662525f016f..719a2fd23ae 100644
--- a/drivers/mtd/spi/sf-uclass.c
+++ b/drivers/mtd/spi/sf-uclass.c
@@ -28,6 +28,15 @@ int spi_flash_erase_dm(struct udevice *dev, u32 offset, size_t len)
return log_ret(sf_get_ops(dev)->erase(dev, offset, len));
}

+int spl_flash_get_sw_write_prot(struct udevice *dev)
+{
+ struct dm_spi_flash_ops *ops = sf_get_ops(dev);
+
+ if (!ops->get_sw_write_prot)
+ return -ENOSYS;
+ return log_ret(ops->get_sw_write_prot(dev));
+}
+
/*
* TODO(sjg at chromium.org): This is an old-style function. We should remove
* it when all SPI flash drivers use dm
diff --git a/drivers/mtd/spi/sf_internal.h b/drivers/mtd/spi/sf_internal.h
index 26f5c7c995e..46a50444175 100644
--- a/drivers/mtd/spi/sf_internal.h
+++ b/drivers/mtd/spi/sf_internal.h
@@ -170,6 +170,9 @@ int spi_flash_cmd_write(struct spi_slave *spi, const u8 *cmd, size_t cmd_len,
/* Flash erase(sectors) operation, support all possible erase commands */
int spi_flash_cmd_erase_ops(struct spi_flash *flash, u32 offset, size_t len);

+/* Get software write-protect value (BP bits) */
+int spi_flash_cmd_get_sw_write_prot(struct spi_flash *flash);
+
/* Lock stmicro spi flash region */
int stm_lock(struct spi_flash *flash, u32 ofs, size_t len);

diff --git a/drivers/mtd/spi/sf_probe.c b/drivers/mtd/spi/sf_probe.c
index 94fde2ae7a3..5a2e932de8f 100644
--- a/drivers/mtd/spi/sf_probe.c
+++ b/drivers/mtd/spi/sf_probe.c
@@ -124,6 +124,13 @@ static int spi_flash_std_erase(struct udevice *dev, u32 offset, size_t len)
return spi_flash_cmd_erase_ops(flash, offset, len);
}

+static int spi_flash_std_get_sw_write_prot(struct udevice *dev)
+{
+ struct spi_flash *flash = dev_get_uclass_priv(dev);
+
+ return spi_flash_cmd_get_sw_write_prot(flash);
+}
+
static int spi_flash_std_probe(struct udevice *dev)
{
struct spi_slave *slave = dev_get_parent_priv(dev);
@@ -141,6 +148,7 @@ static const struct dm_spi_flash_ops spi_flash_std_ops = {
.read = spi_flash_std_read,
.write = spi_flash_std_write,
.erase = spi_flash_std_erase,
+ .get_sw_write_prot = spi_flash_std_get_sw_write_prot,
};

static const struct udevice_id spi_flash_std_ids[] = {
diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
index a87bacd4ac7..0c2392f28a4 100644
--- a/drivers/mtd/spi/spi_flash.c
+++ b/drivers/mtd/spi/spi_flash.c
@@ -110,6 +110,18 @@ static int write_cr(struct spi_flash *flash, u8 wc)
}
#endif

+int spi_flash_cmd_get_sw_write_prot(struct spi_flash *flash)
+{
+ u8 status;
+ int ret;
+
+ ret = read_sr(flash, &status);
+ if (ret)
+ return ret;
+
+ return (status >> 2) & 7;
+}
+
#ifdef CONFIG_SPI_FLASH_BAR
/*
* This "clean_bar" is necessary in a situation when one was accessing
diff --git a/include/spi_flash.h b/include/spi_flash.h
index 0ec98fb55df..e427e960d54 100644
--- a/include/spi_flash.h
+++ b/include/spi_flash.h
@@ -112,6 +112,19 @@ struct dm_spi_flash_ops {
int (*write)(struct udevice *dev, u32 offset, size_t len,
const void *buf);
int (*erase)(struct udevice *dev, u32 offset, size_t len);
+ /**
+ * get_sw_write_prot() - Check state of software write-protect feature
+ *
+ * SPI flash chips can lock a region of the flash defined by a
+ * 'protected area'. This function checks if this protected area is
+ * defined.
+ *
+ * @dev: SPI flash device
+ * @return 0 if no region is write-protected, 1 if a region is
+ * write-protected, -ENOSYS if the driver does not implement this,
+ * other -ve value on error
+ */
+ int (*get_sw_write_prot)(struct udevice *dev);
};

/* Access the serial operations for a device */
@@ -153,6 +166,20 @@ int spi_flash_write_dm(struct udevice *dev, u32 offset, size_t len,
*/
int spi_flash_erase_dm(struct udevice *dev, u32 offset, size_t len);

+/**
+ * spl_flash_get_sw_write_prot() - Check state of software write-protect feature
+ *
+ * SPI flash chips can lock a region of the flash defined by a
+ * 'protected area'. This function checks if this protected area is
+ * defined.
+ *
+ * @dev: SPI flash device
+ * @return 0 if no region is write-protected, 1 if a region is
+ * write-protected, -ENOSYS if the driver does not implement this,
+ * other -ve value on error
+ */
+int spl_flash_get_sw_write_prot(struct udevice *dev);
+
int spi_flash_probe_bus_cs(unsigned int busnum, unsigned int cs,
unsigned int max_hz, unsigned int spi_mode,
struct udevice **devp);
diff --git a/test/dm/sf.c b/test/dm/sf.c
index b23e7f8edd4..35dce4e4c98 100644
--- a/test/dm/sf.c
+++ b/test/dm/sf.c
@@ -11,6 +11,7 @@
#include <spi.h>
#include <spi_flash.h>
#include <asm/state.h>
+#include <asm/test.h>
#include <dm/test.h>
#include <dm/util.h>
#include <test/ut.h>
@@ -45,6 +46,14 @@ static int dm_test_spi_flash(struct unit_test_state *uts)
ut_assertok(spi_flash_read_dm(dev, 0, size, dst));
ut_assertok(memcmp(src, dst, size));

+ /* Try the write-protect stuff */
+ ut_assertok(uclass_first_device_err(UCLASS_SPI_EMUL, &emul));
+ ut_asserteq(0, spl_flash_get_sw_write_prot(dev));
+ sandbox_sf_set_block_protect(emul, 1);
+ ut_asserteq(1, spl_flash_get_sw_write_prot(dev));
+ sandbox_sf_set_block_protect(emul, 0);
+ ut_asserteq(0, spl_flash_get_sw_write_prot(dev));
+
/*
* Since we are about to destroy all devices, we must tell sandbox
* to forget the emulation device
--
2.19.1.930.g4563a0d9d0-goog