ARM: EXYNOS: Do not resume l2x0 if not enabled before suspend

Trying to resume l2x0 if it was not enabled before suspend leads to
system crash. This patch prevents this by checking if l2x0_regs_phys is
a valid pointer to l2x0 context data saved on initialization.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

diff --git a/arch/arm/plat-samsung/s5p-sleep.S b/arch/arm/plat-samsung/s5p-sleep.S
index a030e7301da86a3654fb16cb0f9412280e192594..20764bd5518e43d2fd8bc9100dda32cc9e670119 100644 (file)
--- a/arch/arm/plat-samsung/s5p-sleep.S
+++ b/arch/arm/plat-samsung/s5p-sleep.S
@@ -59,13 +59,15 @@ ENTRY(s3c_cpu_resume)
        and     r0, r0, r1
        ldr     r1, =CPU_CORTEX_A9
        cmp     r0, r1
-       bne     resume_l2on
+       bne     skip_l2_resume
        adr     r0, l2x0_regs_phys
        ldr     r0, [r0]
+       cmp     r0, #0
+       beq     skip_l2_resume
        ldr     r1, [r0, #L2X0_R_PHY_BASE]
        ldr     r2, [r1, #L2X0_CTRL]
        tst     r2, #0x1
-       bne     resume_l2on
+       bne     skip_l2_resume
        ldr     r2, [r0, #L2X0_R_AUX_CTRL]
        str     r2, [r1, #L2X0_AUX_CTRL]
        ldr     r2, [r0, #L2X0_R_TAG_LATENCY]
@@ -78,7 +80,7 @@ ENTRY(s3c_cpu_resume)
        str     r2, [r1, #L2X0_POWER_CTRL]
        mov     r2, #1
        str     r2, [r1, #L2X0_CTRL]
-resume_l2on:
+skip_l2_resume:
 #endif
        b       cpu_resume
 ENDPROC(s3c_cpu_resume)