4 files changed, 63 insertions, 3 deletions

diff --git a/arch/arm/mach-mx3/Makefile b/arch/arm/mach-mx3/Makefile
index ed492d32b664..940035cacae8 100644
--- a/arch/arm/mach-mx3/Makefile
+++ b/arch/arm/mach-mx3/Makefile
@@ -4,7 +4,7 @@
 
 # Object file lists.
 
-obj-y                           := mm.o devices.o
+obj-y                           := mm.o devices.o cpu.o
 obj-$(CONFIG_ARCH_MX31)         += clock.o iomux.o
 obj-$(CONFIG_ARCH_MX35)         += clock-imx35.o
 obj-$(CONFIG_MACH_MX31ADS)      += mx31ads.o
diff --git a/arch/arm/mach-mx3/clock.c b/arch/arm/mach-mx3/clock.c
index b2a3bcf8266e..bec097d176e6 100644
--- a/arch/arm/mach-mx3/clock.c
+++ b/arch/arm/mach-mx3/clock.c
@@ -616,6 +616,8 @@ int __init mx31_clocks_init(unsigned long fref)
 
         clk_enable(&serial_pll_clk);
 
+        mx31_read_cpu_rev();
+
         if (mx31_revision() >= CHIP_REV_2_0) {
                 reg = __raw_readl(MXC_CCM_PMCR1);
                 /* No PLL restart on DVFS switch; enable auto EMI handshake */
diff --git a/arch/arm/mach-mx3/cpu.c b/arch/arm/mach-mx3/cpu.c
new file mode 100644
index 000000000000..db828809c675
--- /dev/null
+++ b/arch/arm/mach-mx3/cpu.c
@@ -0,0 +1,57 @@
+/*
+ * MX3 CPU type detection
+ *
+ * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/io.h>
+#include <mach/hardware.h>
+#include <mach/iim.h>
+
+unsigned int mx31_cpu_rev;
+EXPORT_SYMBOL(mx31_cpu_rev);
+
+struct mx3_cpu_type {
+        u8 srev;
+        const char *name;
+        const char *v;
+        unsigned int rev;
+};
+
+static struct mx3_cpu_type mx31_cpu_type[] __initdata = {
+        { .srev = 0x00, .name = "i.MX31(L)", .v = "1.0",  .rev = CHIP_REV_1_0   },
+        { .srev = 0x10, .name = "i.MX31",    .v = "1.1",  .rev = CHIP_REV_1_1   },
+        { .srev = 0x11, .name = "i.MX31L",   .v = "1.1",  .rev = CHIP_REV_1_1   },
+        { .srev = 0x12, .name = "i.MX31",    .v = "1.15", .rev = CHIP_REV_1_1   },
+        { .srev = 0x13, .name = "i.MX31L",   .v = "1.15", .rev = CHIP_REV_1_1   },
+        { .srev = 0x14, .name = "i.MX31",    .v = "1.2",  .rev = CHIP_REV_1_2   },
+        { .srev = 0x15, .name = "i.MX31L",   .v = "1.2",  .rev = CHIP_REV_1_2   },
+        { .srev = 0x28, .name = "i.MX31",    .v = "2.0",  .rev = CHIP_REV_2_0   },
+        { .srev = 0x29, .name = "i.MX31L",   .v = "2.0",  .rev = CHIP_REV_2_0   },
+};
+
+void __init mx31_read_cpu_rev(void)
+{
+        u32 i, srev;
+
+        /* read SREV register from IIM module */
+        srev = __raw_readl(IO_ADDRESS(IIM_BASE_ADDR) + MXC_IIMSREV);
+
+        for (i = 0; i < ARRAY_SIZE(mx31_cpu_type); i++)
+                if (srev == mx31_cpu_type[i].srev) {
+                        printk(KERN_INFO
+                                "CPU identified as %s, silicon rev %s\n",
+                                mx31_cpu_type[i].name, mx31_cpu_type[i].v);
+
+                        mx31_cpu_rev = mx31_cpu_type[i].rev;
+                        return;
+                }
+
+        printk(KERN_WARNING "Unknown CPU identifier. srev = %02x\n", srev);
+}
diff --git a/arch/arm/plat-mxc/include/mach/mx3x.h b/arch/arm/plat-mxc/include/mach/mx3x.h
index 8cedf29eee16..be69272407ad 100644
--- a/arch/arm/plat-mxc/include/mach/mx3x.h
+++ b/arch/arm/plat-mxc/include/mach/mx3x.h
@@ -260,11 +260,12 @@
 
 #if !defined(__ASSEMBLY__) && !defined(__MXC_BOOT_UNCOMPRESS)
 
-extern unsigned int system_rev;
+extern unsigned int mx31_cpu_rev;
+extern void mx31_read_cpu_rev(void);
 
 static inline int mx31_revision(void)
 {
-        return system_rev;
+        return mx31_cpu_rev;
 }
 #endif