MX31 Reference Manual states the following possible values for the silicon revision:
.srev = 0x00, .srev = 0x10, .srev = 0x11, .srev = 0x12, .srev = 0x13, .srev = 0x14, .srev = 0x15, .srev = 0x28, .srev = 0x29,
However it is possible to find some pre-production silicon on some old hardware, such as MX31ADS that shows srev = 0x20.
The following message is the currently displayed on such MX31ADS board:
CPU: Freescale i.MX31 rev 2.0 unknown at 531 MHz.Reset cause: WDOG
With this patch we see a better message like:
CPU: Freescale i.MX31 rev 0.0 (unknown revision) at 531 MHz.Reset cause: WDOG
Reported-by: Felix Radensky felix@embedded-sol.com Signed-off-by: Fabio Estevam fabio.estevam@freescale.com --- arch/arm/cpu/arm1136/mx31/generic.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm/cpu/arm1136/mx31/generic.c b/arch/arm/cpu/arm1136/mx31/generic.c index 4ebf38d..770d359 100644 --- a/arch/arm/cpu/arm1136/mx31/generic.c +++ b/arch/arm/cpu/arm1136/mx31/generic.c @@ -130,7 +130,7 @@ u32 get_cpu_rev(void) if (srev == mx31_cpu_type[i].srev) return mx31_cpu_type[i].v;
- return srev | 0x8000; + return 0x8000; }
static char *get_reset_cause(void) @@ -162,7 +162,7 @@ int print_cpuinfo (void)
printf("CPU: Freescale i.MX31 rev %d.%d%s at %d MHz.", (srev & 0xF0) >> 4, (srev & 0x0F), - ((srev & 0x8000) ? " unknown" : ""), + ((srev & 0x8000) ? " (unknown revision)" : ""), mx31_get_mcu_main_clk() / 1000000); printf("Reset cause: %s\n", get_reset_cause()); return 0;