From: Michiel Schelfhout <michiel.schelfhout@xxxxxxxxxxx>
Introduce support for retrieving the board-specific serial number from
BSEC registers via the OP-TEE interface. The serial number is stored
across three 4-byte registers (58, 59, 60), with only the lower 16 bits
of register 58 being relevant.
Signed-off-by: Michiel Schelfhout <michiel.schelfhout@xxxxxxxxxxx>
Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
---
arch/arm/boards/protonic-stm32mp1/board.c | 61 +++++++++++++++++++++++
1 file changed, 61 insertions(+)
diff --git a/arch/arm/boards/protonic-stm32mp1/board.c b/arch/arm/boards/protonic-stm32mp1/board.c
index 0b46dccb3247..cafdc20c2b42 100644
--- a/arch/arm/boards/protonic-stm32mp1/board.c
+++ b/arch/arm/boards/protonic-stm32mp1/board.c
@@ -6,14 +6,20 @@
#include <common.h>
#include <init.h>
#include <mach/stm32mp/bbu.h>
+#include <mach/stm32mp/bsec.h>
#include <of_device.h>
#include <deep-probe.h>
+#include <soc/stm32/stm32-bsec-optee-ta.h>
/* board specific flags */
#define PRT_STM32_BOOTSRC_SD BIT(2)
#define PRT_STM32_BOOTSRC_EMMC BIT(1)
#define PRT_STM32_BOOTSRC_SPI_NOR BIT(0)
+/* board specific serial number length is 10 characters without '\0' */
+#define PRT_STM32_SERIAL_LEN 10
+#define PRT_STM32_SERIAL_OFFSET 58
+
struct prt_stm32_machine_data {
u32 flags;
};
@@ -54,6 +60,59 @@ static const struct prt_stm32_boot_dev prt_stm32_boot_devs[] = {
},
};
+static int prt_stm32_set_serial(struct device *dev, char *serial)
+{
+ dev_info(dev, "Serial number: %s\n", serial);
+ barebox_set_serial_number(serial);
+
+ return 0;
+}
+
+static int prt_stm32_read_serial(struct device *dev)
+{
+ /* including first 2 non-serial bytes */
+ char raw_serial[PRT_STM32_SERIAL_LEN + 2];
+ /* board specific serial number + one char for '\0' */
+ char serial[PRT_STM32_SERIAL_LEN + 1];
+ struct tee_context *ctx;
+ int ret;
+
+ /* the ctx pointer will be set in the stm32_bsec_optee_ta_open */
+ ret = stm32_bsec_optee_ta_open(&ctx);
+ if (ret) {
+ dev_err(dev, "Failed to open BSEC TA: %pe\n", ERR_PTR(ret));
+ return ret;
+ }
+
+ ret = stm32_bsec_optee_ta_read(ctx, PRT_STM32_SERIAL_OFFSET * 4,
+ &raw_serial, sizeof(raw_serial));
+ if (ret)
+ goto exit_pta_read;
+
+ /*
+ * Shift the serial data left by 2 bytes to remove the non-serial data.
+ * The serial number is stored across three 4-byte BSEC registers:
+ * - Register 58 (4 bytes): Only the lower 16 bits contain serial data.
+ * - Register 59 (4 bytes): Fully part of the serial number.
+ * - Register 60 (4 bytes): Fully part of the serial number.
+ * Since we read all three registers as a continuous block (12 bytes),
+ * the first 2 bytes of Register 58 contain irrelevant data and must
+ * be discarded.
+ */
+ memmove(serial, raw_serial + 2, sizeof(serial) - 1);
+
+ serial[PRT_STM32_SERIAL_LEN] = 0;
+
+ stm32_bsec_optee_ta_close(&ctx);
+
+ return prt_stm32_set_serial(dev, serial);
+
+exit_pta_read:
+ stm32_bsec_optee_ta_close(&ctx);
+ dev_err(dev, "Failed to read serial: %pe\n", ERR_PTR(ret));
+ return ret;
+}
+
static int prt_stm32_probe(struct device *dev)
{
const struct prt_stm32_machine_data *dcfg;
@@ -66,6 +125,8 @@ static int prt_stm32_probe(struct device *dev)
goto exit_get_dcfg;
}
+ prt_stm32_read_serial(dev);
+
for (i = 0; i < ARRAY_SIZE(prt_stm32_boot_devs); i++) {
const struct prt_stm32_boot_dev *bd = &prt_stm32_boot_devs[i];
int bbu_flags = 0;
--
2.39.5
