arm: ls102xa: workaround for cache coherency problem

The RCPM FSM may not be reset after power-on, for example,
in the cases of cold boot and wakeup from deep sleep.
It causes cache coherency problem and may block deep sleep.
Therefore, reset them if they are not be reset.

Signed-off-by: Chenhui Zhao <chenhui.zhao@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>

diff --git a/arch/arm/cpu/armv7/ls102xa/cpu.c b/arch/arm/cpu/armv7/ls102xa/cpu.c
index 18665a3..1a640bb 100644 (file)
--- a/arch/arm/cpu/armv7/ls102xa/cpu.c
+++ b/arch/arm/cpu/armv7/ls102xa/cpu.c
@@ -16,6 +16,13 @@
 
 #include "fsl_epu.h"
 
+#define DCSR_RCPM2_BLOCK_OFFSET        0x223000
+#define DCSR_RCPM2_CPMFSMCR0   0x400
+#define DCSR_RCPM2_CPMFSMSR0   0x404
+#define DCSR_RCPM2_CPMFSMCR1   0x414
+#define DCSR_RCPM2_CPMFSMSR1   0x418
+#define CPMFSMSR_FSM_STATE_MASK        0x7f
+
 DECLARE_GLOBAL_DATA_PTR;
 
 #ifndef CONFIG_SYS_DCACHE_OFF
@@ -290,6 +297,27 @@ int cpu_eth_init(bd_t *bis)
 int arch_cpu_init(void)
 {
        void *epu_base = (void *)(CONFIG_SYS_DCSRBAR + EPU_BLOCK_OFFSET);
+       void *rcpm2_base =
+               (void *)(CONFIG_SYS_DCSRBAR + DCSR_RCPM2_BLOCK_OFFSET);
+       u32 state;
+
+       /*
+        * The RCPM FSM state may not be reset after power-on.
+        * So, reset them.
+        */
+       state = in_be32(rcpm2_base + DCSR_RCPM2_CPMFSMSR0) &
+               CPMFSMSR_FSM_STATE_MASK;
+       if (state != 0) {
+               out_be32(rcpm2_base + DCSR_RCPM2_CPMFSMCR0, 0x80);
+               out_be32(rcpm2_base + DCSR_RCPM2_CPMFSMCR0, 0x0);
+       }
+
+       state = in_be32(rcpm2_base + DCSR_RCPM2_CPMFSMSR1) &
+               CPMFSMSR_FSM_STATE_MASK;
+       if (state != 0) {
+               out_be32(rcpm2_base + DCSR_RCPM2_CPMFSMCR1, 0x80);
+               out_be32(rcpm2_base + DCSR_RCPM2_CPMFSMCR1, 0x0);
+       }
 
        /*
         * After wakeup from deep sleep, Clear EPU registers