aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-imx/headsmp.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mach-imx/headsmp.S')
-rw-r--r--arch/arm/mach-imx/headsmp.S106
1 files changed, 106 insertions, 0 deletions
diff --git a/arch/arm/mach-imx/headsmp.S b/arch/arm/mach-imx/headsmp.S
new file mode 100644
index 0000000..7e49deb
--- /dev/null
+++ b/arch/arm/mach-imx/headsmp.S
@@ -0,0 +1,106 @@
+/*
+ * Copyright 2011 Freescale Semiconductor, Inc.
+ * Copyright 2011 Linaro Ltd.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/linkage.h>
+#include <linux/init.h>
+#include <asm/asm-offsets.h>
+#include <asm/hardware/cache-l2x0.h>
+
+ .section ".text.head", "ax"
+
+/*
+ * The secondary kernel init calls v7_flush_dcache_all before it enables
+ * the L1; however, the L1 comes out of reset in an undefined state, so
+ * the clean + invalidate performed by v7_flush_dcache_all causes a bunch
+ * of cache lines with uninitialized data and uninitialized tags to get
+ * written out to memory, which does really unpleasant things to the main
+ * processor. We fix this by performing an invalidate, rather than a
+ * clean + invalidate, before jumping into the kernel.
+ *
+ * This funciton is cloned from arch/arm/mach-tegra/headsmp.S, and needs
+ * to be called for both secondary cores startup and primary core resume
+ * procedures. Ideally, it should be moved into arch/arm/mm/cache-v7.S.
+ */
+ENTRY(v7_invalidate_l1)
+ mov r0, #0
+ mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
+ mcr p15, 2, r0, c0, c0, 0
+ mrc p15, 1, r0, c0, c0, 0
+
+ ldr r1, =0x7fff
+ and r2, r1, r0, lsr #13
+
+ ldr r1, =0x3ff
+
+ and r3, r1, r0, lsr #3 @ NumWays - 1
+ add r2, r2, #1 @ NumSets
+
+ and r0, r0, #0x7
+ add r0, r0, #4 @ SetShift
+
+ clz r1, r3 @ WayShift
+ add r4, r3, #1 @ NumWays
+1: sub r2, r2, #1 @ NumSets--
+ mov r3, r4 @ Temp = NumWays
+2: subs r3, r3, #1 @ Temp--
+ mov r5, r3, lsl r1
+ mov r6, r2, lsl r0
+ orr r5, r5, r6 @ Reg = (Temp<<WayShift)|(NumSets<<SetShift)
+ mcr p15, 0, r5, c7, c6, 2
+ bgt 2b
+ cmp r2, #0
+ bgt 1b
+ dsb
+ isb
+ mov pc, lr
+ENDPROC(v7_invalidate_l1)
+
+#ifdef CONFIG_SMP
+ENTRY(v7_secondary_startup)
+ bl v7_invalidate_l1
+ b secondary_startup
+ENDPROC(v7_secondary_startup)
+#endif
+
+#ifdef CONFIG_PM
+/*
+ * The following code is located into the .data section. This is to
+ * allow phys_l2x0_saved_regs to be accessed with a relative load
+ * as we are running on physical address here.
+ */
+ .data
+ .align
+
+#ifdef CONFIG_CACHE_L2X0
+ .macro pl310_resume
+ ldr r2, phys_l2x0_saved_regs
+ ldr r0, [r2, #L2X0_R_PHY_BASE] @ get physical base of l2x0
+ ldr r1, [r2, #L2X0_R_AUX_CTRL] @ get aux_ctrl value
+ str r1, [r0, #L2X0_AUX_CTRL] @ restore aux_ctrl
+ mov r1, #0x1
+ str r1, [r0, #L2X0_CTRL] @ re-enable L2
+ .endm
+
+ .globl phys_l2x0_saved_regs
+phys_l2x0_saved_regs:
+ .long 0
+#else
+ .macro pl310_resume
+ .endm
+#endif
+
+ENTRY(v7_cpu_resume)
+ bl v7_invalidate_l1
+ pl310_resume
+ b cpu_resume
+ENDPROC(v7_cpu_resume)
+#endif