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

[Shawn Guo]

On Wed, Nov 11, 2020 at 08:18:59AM +0300, Ivan Zaentsev wrote:
> 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 at wirenboard.ru>
> Suggested-by: Evgeny Boger <boger at wirenboard.com>
> ---
>  arch/arm/mach-mxs/mach-mxs.c | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
> 
> diff --git a/arch/arm/mach-mxs/mach-mxs.c b/arch/arm/mach-mxs/mach-mxs.c
> index c109f47e9cbc..af96368cc16a 100644
> --- a/arch/arm/mach-mxs/mach-mxs.c
> +++ b/arch/arm/mach-mxs/mach-mxs.c
> @@ -23,6 +23,7 @@
>  #include <asm/mach/map.h>
>  #include <asm/mach/time.h>
>  #include <asm/system_misc.h>
> +#include <asm/system_info.h>

Can we move it above <asm/system_misc.h> to get them alphabetically
sorted?

>  
>  #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 */

Use tabs instead of spaces for indent.

> +
>  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 +400,22 @@ 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);
> +

Unnecessary newline.

Shawn

>  	if (IS_ERR(soc_dev)) {
> +		kfree(soc_dev_attr->serial_number);
>  		kfree(soc_dev_attr->revision);
>  		kfree(soc_dev_attr);
>  		return;
> -- 
> 2.25.1
>