ARM: mxs: Add serial number support for i.MX23, i.MX28 SoCs

i.MX23 and i.MX28 SoCs unique identifiers are factory-programmed
in On-Chip OTP memory. i.MX28's 64-bit unique id is in
HW_OCOTP_OPS2:HW_OCOTP_OPS3 (see MCIMX28 Ref. Man., sec. 20.4.22-23).

i.MX23 provides 32-bit long unique id in HW_OCOTP_OPS3.
Though not clearly documented, there is a clue in sec. 35.9.3.

The unique id is reported in /sys/devices/soc0/serial_number
and in /proc/cpuinfo

Signed-off-by: Ivan Zaentsev <ivan.zaentsev@wirenboard.ru>
Suggested-by: Evgeny Boger <boger@wirenboard.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
This commit is contained in:
Ivan Zaentsev 2020-11-16 19:58:26 +03:00 committed by Shawn Guo
parent 53cc6bc69e
commit 4ba79e25d7

View File

@ -22,6 +22,7 @@
#include <asm/mach/arch.h>
#include <asm/mach/map.h>
#include <asm/mach/time.h>
#include <asm/system_info.h>
#include <asm/system_misc.h>
#include "pm.h"
@ -51,6 +52,9 @@
#define MXS_CLR_ADDR 0x8
#define MXS_TOG_ADDR 0xc
#define HW_OCOTP_OPS2 19 /* offset 0x150 */
#define HW_OCOTP_OPS3 20 /* offset 0x160 */
static u32 chipid;
static u32 socid;
@ -379,6 +383,8 @@ static void __init mxs_machine_init(void)
struct device *parent;
struct soc_device *soc_dev;
struct soc_device_attribute *soc_dev_attr;
u64 soc_uid = 0;
const u32 *ocotp = mxs_get_ocotp();
int ret;
soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
@ -394,8 +400,21 @@ static void __init mxs_machine_init(void)
soc_dev_attr->soc_id = mxs_get_soc_id();
soc_dev_attr->revision = mxs_get_revision();
if (socid == HW_DIGCTL_CHIPID_MX23) {
soc_uid = system_serial_low = ocotp[HW_OCOTP_OPS3];
} else if (socid == HW_DIGCTL_CHIPID_MX28) {
soc_uid = system_serial_high = ocotp[HW_OCOTP_OPS2];
soc_uid <<= 32;
system_serial_low = ocotp[HW_OCOTP_OPS3];
soc_uid |= system_serial_low;
}
if (soc_uid)
soc_dev_attr->serial_number = kasprintf(GFP_KERNEL, "%016llX", soc_uid);
soc_dev = soc_device_register(soc_dev_attr);
if (IS_ERR(soc_dev)) {
kfree(soc_dev_attr->serial_number);
kfree(soc_dev_attr->revision);
kfree(soc_dev_attr);
return;