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authorRussell King <rmk+kernel@arm.linux.org.uk>2014-04-05 14:39:57 +0400
committerRussell King <rmk+kernel@arm.linux.org.uk>2014-05-30 03:49:01 +0400
commitde7e75326c05c10ebd96aed9440c870f0ff1e34f (patch)
treeab355bd6cbca63d6e0eccb565485e6fff24762b9 /arch/arm
parent805604ef8596968e5f251c69fd92bd3b8f466317 (diff)
downloadlinux-de7e75326c05c10ebd96aed9440c870f0ff1e34f.tar.xz
ARM: l2c: provide common PL310 early resume code
Provide a common assembly implementation for PL310 resume code. Certain platforms need to re-initialise the L2C cache early as it may preserve data across a S2RAM cycle, and therefore must be enabled along with the L1 cache and MMU. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm')
-rw-r--r--arch/arm/mm/Makefile2
-rw-r--r--arch/arm/mm/l2c-l2x0-resume.S58
2 files changed, 59 insertions, 1 deletions
diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile
index de5a6a27081b..91da64de440f 100644
--- a/arch/arm/mm/Makefile
+++ b/arch/arm/mm/Makefile
@@ -97,6 +97,6 @@ AFLAGS_proc-v7.o :=-Wa,-march=armv7-a
obj-$(CONFIG_OUTER_CACHE) += l2c-common.o
obj-$(CONFIG_CACHE_FEROCEON_L2) += cache-feroceon-l2.o
-obj-$(CONFIG_CACHE_L2X0) += cache-l2x0.o
+obj-$(CONFIG_CACHE_L2X0) += cache-l2x0.o l2c-l2x0-resume.o
obj-$(CONFIG_CACHE_XSC3L2) += cache-xsc3l2.o
obj-$(CONFIG_CACHE_TAUROS2) += cache-tauros2.o
diff --git a/arch/arm/mm/l2c-l2x0-resume.S b/arch/arm/mm/l2c-l2x0-resume.S
new file mode 100644
index 000000000000..99b05f21a59a
--- /dev/null
+++ b/arch/arm/mm/l2c-l2x0-resume.S
@@ -0,0 +1,58 @@
+/*
+ * L2C-310 early resume code. This can be used by platforms to restore
+ * the settings of their L2 cache controller before restoring the
+ * processor state.
+ *
+ * This code can only be used to if you are running in the secure world.
+ */
+#include <linux/linkage.h>
+#include <asm/hardware/cache-l2x0.h>
+
+ .text
+
+ENTRY(l2c310_early_resume)
+ adr r0, 1f
+ ldr r2, [r0]
+ add r0, r2, r0
+
+ ldmia r0, {r1, r2, r3, r4, r5, r6, r7, r8}
+ @ r1 = phys address of L2C-310 controller
+ @ r2 = aux_ctrl
+ @ r3 = tag_latency
+ @ r4 = data_latency
+ @ r5 = filter_start
+ @ r6 = filter_end
+ @ r7 = prefetch_ctrl
+ @ r8 = pwr_ctrl
+
+ @ Check that the address has been initialised
+ teq r1, #0
+ moveq pc, lr
+
+ @ The prefetch and power control registers are revision dependent
+ @ and can be written whether or not the L2 cache is enabled
+ ldr r0, [r1, #L2X0_CACHE_ID]
+ and r0, r0, #L2X0_CACHE_ID_RTL_MASK
+ cmp r0, #L310_CACHE_ID_RTL_R2P0
+ strcs r7, [r1, #L310_PREFETCH_CTRL]
+ cmp r0, #L310_CACHE_ID_RTL_R3P0
+ strcs r8, [r1, #L310_POWER_CTRL]
+
+ @ Don't setup the L2 cache if it is already enabled
+ ldr r0, [r1, #L2X0_CTRL]
+ tst r0, #L2X0_CTRL_EN
+ movne pc, lr
+
+ str r3, [r1, #L310_TAG_LATENCY_CTRL]
+ str r4, [r1, #L310_DATA_LATENCY_CTRL]
+ str r6, [r1, #L310_ADDR_FILTER_END]
+ str r5, [r1, #L310_ADDR_FILTER_START]
+
+ str r2, [r1, #L2X0_AUX_CTRL]
+ mov r9, #L2X0_CTRL_EN
+ str r9, [r1, #L2X0_CTRL]
+ mov pc, lr
+ENDPROC(l2c310_early_resume)
+
+ .align
+1: .long l2x0_saved_regs - .