arch: arm: meson: support Amlogic chip_id v1 and v2
Patch introduces:
* chip_id API - useful for various things, but used now for
device_id (did) generation as mentioned in [1] on our private board
code. Our device_id is calculated by means of permutations of
chip_id value.
* new SoCs (a1, s4, etc) are usually coming with the support of chip_id
v2 right away, whereas secure monitors on old SoCs (like axg, g12b,
g12a, etc) may support only chip_id v1. Chip_id API handles both
cases
* meson_sm_get_serial() is described via chip_id API.
Links:
[1] https://lore.kernel.org/linux-arm-kernel/202311242104.RjBPI3uI-lkp@intel.com/T/#m630fbeea6a6e7d531290b5c0af205af4fb979757
Signed-off-by: Viacheslav Bocharov <adeep@lexina.in>
Co-developed-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
Signed-off-by: Evgeny Bachinin <EABachinin@salutedevices.com>
Link: https://lore.kernel.org/r/20250210-meson_chip_id_all_vers-v1-3-b98f8b6880b8@salutedevices.com
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
diff --git a/arch/arm/include/asm/arch-meson/sm.h b/arch/arm/include/asm/arch-meson/sm.h
index 4b1d564..4d61495 100644
--- a/arch/arm/include/asm/arch-meson/sm.h
+++ b/arch/arm/include/asm/arch-meson/sm.h
@@ -6,6 +6,8 @@
#ifndef __MESON_SM_H__
#define __MESON_SM_H__
+#include <asm/types.h>
+
/**
* meson_sm_read_efuse - read efuse memory into buffer
*
@@ -27,16 +29,60 @@
ssize_t meson_sm_write_efuse(uintptr_t offset, void *buffer, size_t size);
#define SM_SERIAL_SIZE 12
+#define MESON_CPU_ID_SZ 4
+#define MESON_CHIP_ID_SZ 16
+
+/**
+ * union meson_cpu_id - Amlogic cpu_id.
+ * @raw: buffer to hold the cpu_id value as sequential bytes.
+ * @val: cpu_id represented as 32 bit value.
+ */
+union meson_cpu_id {
+ u8 raw[MESON_CPU_ID_SZ];
+ u32 val;
+};
/**
- * meson_sm_get_serial - read chip unique id into buffer
+ * struct meson_sm_chip_id - Amlogic chip_id.
+ * @cpu_id: cpu_id value, which is distinct from socinfo in that the order of
+ * PACK & MINOR bytes are swapped according to Amlogic chip_id format.
+ * @serial: 12 byte unique SoC number, identifying particular die, read
+ * usually from efuse OTP storage. Serial comes in little-endian
+ * order.
+ */
+struct meson_sm_chip_id {
+ union meson_cpu_id cpu_id;
+ u8 serial[SM_SERIAL_SIZE];
+};
+
+/**
+ * meson_sm_get_serial - read chip unique serial (OTP data) into buffer
*
* @buffer: pointer to buffer
* @size: buffer size.
+ *
+ * Serial is returned in big-endian order.
+ *
* @return: zero on success or -errno on failure
*/
int meson_sm_get_serial(void *buffer, size_t size);
+/**
+ * meson_sm_get_chip_id - read Amlogic chip_id
+ *
+ * @chip_id: pointer to buffer capable to hold the struct meson_sm_chip_id
+ *
+ * Amlogic SoCs support 2 versions of chip_id. Function requests the newest
+ * one (v2), but if chip_id v2 is not supported, then secure monitor returns
+ * v1. All differences between v1 and v2 versions are handled by this function
+ * and chip_id is returned in unified format.
+ *
+ * chip_id contains serial, which is returned here in little-endian order.
+ *
+ * @return: 0 on success or -errno on failure
+ */
+int meson_sm_get_chip_id(struct meson_sm_chip_id *chip_id);
+
enum {
REBOOT_REASON_COLD = 0,
REBOOT_REASON_NORMAL = 1,