[U-Boot] [PATCH] mx31: Improve the handling of unidentified silicon version

[Fabio Estevam]

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 at embedded-sol.com>
Signed-off-by: Fabio Estevam <fabio.estevam at 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;
-- 
1.6.0.4