This is an automated email from the ASF dual-hosted git repository.
acassis pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/nuttx.git
The following commit(s) were added to refs/heads/master by this push:
new 440be49862f arch/arm/src/common/stm32: read UID with 32-bit accesses
440be49862f is described below
commit 440be49862f83bca497673f7f44f08d7883b6e05
Author: raiden00pl <[email protected]>
AuthorDate: Fri Aug 14 15:59:10 2026 +0200
arch/arm/src/common/stm32: read UID with 32-bit accesses
STM32H5 stores the UID in flash memory that supports only 16-bit or
32-bit read accesses. The 8-bit reads introduced with the stm32_uid
unification generate an AHB bus error and hard fault the chip when
the Ethernet driver reads the MAC address.
Read the UID as three 32-bit words into an aligned buffer and copy it
to the caller's buffer. On little-endian ARM the resulting byte order
is identical to byte reads, so behavior is unchanged for the other
STM32 families.
Fixes: https://github.com/apache/nuttx/issues/19771
Signed-off-by: raiden00pl <[email protected]>
Assisted-by: Claude Code
---
arch/arm/src/common/stm32/stm32_uid.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/arch/arm/src/common/stm32/stm32_uid.c
b/arch/arm/src/common/stm32/stm32_uid.c
index 190f38b975f..e710dabcf64 100644
--- a/arch/arm/src/common/stm32/stm32_uid.c
+++ b/arch/arm/src/common/stm32/stm32_uid.c
@@ -40,6 +40,9 @@
#include <nuttx/config.h>
+#include <string.h>
+
+#include "arm_internal.h"
#include "chip.h"
#include "stm32_uid.h"
@@ -51,12 +54,19 @@
void stm32_get_uniqueid(uint8_t uniqueid[12])
{
+ uint32_t uid[3];
int i;
- for (i = 0; i < 12; i++)
+ /* Read the UID with 32-bit accesses. Some parts (STM32H5) store the UID
+ * in flash memory that does not support 8-bit reads.
+ */
+
+ for (i = 0; i < 3; i++)
{
- uniqueid[i] = *((uint8_t *)(STM32_SYSMEM_UID) + i);
+ uid[i] = getreg32(STM32_SYSMEM_UID + 4 * i);
}
+
+ memcpy(uniqueid, uid, 12);
}
#endif /* STM32_SYSMEM_UID */
