ARM: imx6q: print silicon version on boot

i.MX6Q has 3 revisions 1.0, 1.1 and 1.2.  Print revision on boot.

Signed-off-by: Drew Moseley <drew_moseley@mentor.com>
[drew: add proper error checking for function imx6q_revision()]
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

1 files changed, 35 insertions, 0 deletions

diff --git a/arch/arm/mach-imx/mach-imx6q.c b/arch/arm/mach-imx/mach-imx6q.c
index 978b6dd00de4..9511142d436c 100644
--- a/arch/arm/mach-imx/mach-imx6q.c
+++ b/arch/arm/mach-imx/mach-imx6q.c
@@ -38,6 +38,40 @@
 #include "cpuidle.h"
 #include "hardware.h"
 
+#define IMX6Q_ANALOG_DIGPROG    0x260
+
+static int imx6q_revision(void)
+{
+        struct device_node *np;
+        void __iomem *base;
+        static u32 rev;
+
+        if (!rev) {
+                np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-anatop");
+                if (!np)
+                        return IMX_CHIP_REVISION_UNKNOWN;
+                base = of_iomap(np, 0);
+                if (!base) {
+                        of_node_put(np);
+                        return IMX_CHIP_REVISION_UNKNOWN;
+                }
+                rev =  readl_relaxed(base + IMX6Q_ANALOG_DIGPROG);
+                iounmap(base);
+                of_node_put(np);
+        }
+
+        switch (rev & 0xff) {
+        case 0:
+                return IMX_CHIP_REVISION_1_0;
+        case 1:
+                return IMX_CHIP_REVISION_1_1;
+        case 2:
+                return IMX_CHIP_REVISION_1_2;
+        default:
+                return IMX_CHIP_REVISION_UNKNOWN;
+        }
+}
+
 void imx6q_restart(char mode, const char *cmd)
 {
         struct device_node *np;
@@ -192,6 +226,7 @@ static void __init imx6q_timer_init(void)
 {
         mx6q_clocks_init();
         twd_local_timer_of_register();
+        imx_print_silicon_rev("i.MX6Q", imx6q_revision());
 }
 
 static struct sys_timer imx6q_timer = {