[PATCH] ARM: mx6: Add function to read UNIQUE_ID

[Tom Rini]

On Thu, Feb 04, 2021 at 03:52:51PM -0500, Sean Anderson wrote:
> 
> 
> On 2/4/21 3:41 PM, Tom Rini wrote:
> > On Thu, Feb 04, 2021 at 03:29:48PM -0500, Sean Anderson wrote:
> >
> >> This is almost identical to the imx7 version, except that the register
> >> names are different.
> >>
> >> Signed-off-by: Sean Anderson <sean.anderson at seco.com>
> >> ---
> >>
> >>   arch/arm/mach-imx/mx6/soc.c | 33 +++++++++++++++++++++++++++++++++
> >>   1 file changed, 33 insertions(+)
> >>
> >> diff --git a/arch/arm/mach-imx/mx6/soc.c b/arch/arm/mach-imx/mx6/soc.c
> >> index bf6dddfdc9..cb729be46f 100644
> >> --- a/arch/arm/mach-imx/mx6/soc.c
> >> +++ b/arch/arm/mach-imx/mx6/soc.c
> >> @@ -11,6 +11,7 @@
> >>   #include <linux/delay.h>
> >>   #include <linux/errno.h>
> >>   #include <asm/io.h>
> >> +#include <asm/setup.h>
> >>   #include <asm/arch/imx-regs.h>
> >>   #include <asm/arch/clock.h>
> >>   #include <asm/arch/sys_proto.h>
> >> @@ -705,6 +706,38 @@ int arch_misc_init(void)
> >>   }
> >>   #endif
> >>
> >> +#ifdef CONFIG_SERIAL_TAG
> >> +/*
> >> + * UNIQUE_ID describes a unique ID based on silicon wafer
> >> + * and die X/Y position
> >> + *
> >> + * UNIQUE_ID offset 0x410
> >> + * 31:0 fuse 0
> >> + * FSL-wide unique, encoded LOT ID STD II/SJC CHALLENGE/ Unique ID
> >> + *
> >> + * UNIQUE_ID offset 0x420
> >> + * 31:24 fuse 1
> >> + * The X-coordinate of the die location on the wafer/SJC CHALLENGE/
> Unique ID
> >> + * 23:16 fuse 1
> >> + * The Y-coordinate of the die location on the wafer/SJC CHALLENGE/
> Unique ID
> >> + * 15:11 fuse 1
> >> + * The wafer number of the wafer on which the device was fabricated/SJC
> >> + * CHALLENGE/ Unique ID
> >> + * 10:0 fuse 1
> >> + * FSL-wide unique, encoded LOT ID STD II/SJC CHALLENGE/ Unique ID
> >> + */
> >> +void get_board_serial(struct tag_serialnr *serialnr)
> >> +{
> >> +	struct ocotp_regs *ocotp = (struct ocotp_regs *)OCOTP_BASE_ADDR;
> >> +	struct fuse_bank *bank = &ocotp->bank[0];
> >> +	struct fuse_bank0_regs *fuse =
> >> +		(struct fuse_bank0_regs *)bank->fuse_regs;
> >> +
> >> +	serialnr->low = fuse->uid_low;
> >> +	serialnr->high = fuse->uid_high;
> >> +}
> >> +#endif
> >> +
> >>   /*
> >>    * gpr_init() function is common for boards using MX6S, MX6DL, MX6D,
> >>    * MX6Q and MX6QP processors
> >
> > NAK.  This needs to use the normal mechanism to populate "serial#"
> > directly and not abuse the old ATAG infrastructure.
> 
> What is the "normal" mechanism? Define something like
> omap_die_id_serial which sets serial# directly? From what I can tell,
> get_board_serial is the "generic" function for separating the getting of
> the serial from the setting of serial#.

The normal method is more like stm32 (arch/arm/mach-stm32mp/cpu.c) or
rockchip (arch/arm/mach-rockchip/misc.c) where there's no ATAGs legacy
design (which is where omap_die_id_serial is).

-- 
Tom
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 659 bytes
Desc: not available
URL: <https://lists.denx.de/pipermail/u-boot/attachments/20210204/c98d5fc1/attachment.sig>