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-rw-r--r--arch/arm/kernel/sleep.S125
1 files changed, 125 insertions, 0 deletions
diff --git a/arch/arm/kernel/sleep.S b/arch/arm/kernel/sleep.S
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--- /dev/null
+++ b/arch/arm/kernel/sleep.S
@@ -0,0 +1,125 @@
+#include <linux/linkage.h>
+#include <linux/threads.h>
+#include <asm/asm-offsets.h>
+#include <asm/assembler.h>
+#include <asm/glue-cache.h>
+#include <asm/glue-proc.h>
+#include "entry-header.S"
+ .text
+
+/*
+ * Save CPU state for a suspend. This saves the CPU general purpose
+ * registers, and allocates space on the kernel stack to save the CPU
+ * specific registers and some other data for resume.
+ * r0 = suspend function arg0
+ * r1 = suspend function
+ */
+ENTRY(__cpu_suspend)
+ stmfd sp!, {r4 - r11, lr}
+#ifdef MULTI_CPU
+ ldr r10, =processor
+ ldr r4, [r10, #CPU_SLEEP_SIZE] @ size of CPU sleep state
+#else
+ ldr r4, =cpu_suspend_size
+#endif
+ mov r5, sp @ current virtual SP
+ add r4, r4, #12 @ Space for pgd, virt sp, phys resume fn
+ sub sp, sp, r4 @ allocate CPU state on stack
+ stmfd sp!, {r0, r1} @ save suspend func arg and pointer
+ add r0, sp, #8 @ save pointer to save block
+ mov r1, r4 @ size of save block
+ mov r2, r5 @ virtual SP
+ ldr r3, =sleep_save_sp
+#ifdef CONFIG_SMP
+ get_thread_info r5
+ ldr lr, [r5, #TI_CPU] @ cpu logical index
+ add r3, r3, lr, lsl #2
+#endif
+ bl __cpu_suspend_save
+ adr lr, BSYM(cpu_suspend_abort)
+ ldmfd sp!, {r0, pc} @ call suspend fn
+ENDPROC(__cpu_suspend)
+ .ltorg
+
+cpu_suspend_abort:
+ ldmia sp!, {r1 - r3} @ pop phys pgd, virt SP, phys resume fn
+ teq r0, #0
+ moveq r0, #1 @ force non-zero value
+ mov sp, r2
+ ldmfd sp!, {r4 - r11, pc}
+ENDPROC(cpu_suspend_abort)
+
+/*
+ * r0 = control register value
+ */
+ .align 5
+ .pushsection .idmap.text,"ax"
+ENTRY(cpu_resume_mmu)
+ ldr r3, =cpu_resume_after_mmu
+ instr_sync
+ mcr p15, 0, r0, c1, c0, 0 @ turn on MMU, I-cache, etc
+ mrc p15, 0, r0, c0, c0, 0 @ read id reg
+ instr_sync
+ mov r0, r0
+ mov r0, r0
+ mov pc, r3 @ jump to virtual address
+ENDPROC(cpu_resume_mmu)
+ .popsection
+cpu_resume_after_mmu:
+ bl cpu_init @ restore the und/abt/irq banked regs
+ mov r0, #0 @ return zero on success
+ ldmfd sp!, {r4 - r11, pc}
+ENDPROC(cpu_resume_after_mmu)
+
+/*
+ * Note: Yes, part of the following code is located into the .data section.
+ * This is to allow sleep_save_sp to be accessed with a relative load
+ * while we can't rely on any MMU translation. We could have put
+ * sleep_save_sp in the .text section as well, but some setups might
+ * insist on it to be truly read-only.
+ */
+ .data
+ .align
+ENTRY(cpu_resume)
+ARM_BE8(setend be) @ ensure we are in BE mode
+#ifdef CONFIG_SMP
+ mov r1, #0 @ fall-back logical index for UP
+ ALT_SMP(mrc p15, 0, r0, c0, c0, 5)
+ ALT_UP_B(1f)
+ bic r0, #0xff000000
+ bl cpu_logical_index @ return logical index in r1
+1:
+ adr r0, sleep_save_sp
+ ldr r0, [r0, r1, lsl #2] @ stack phys addr
+#else
+ ldr r0, sleep_save_sp @ stack phys addr
+#endif
+ setmode PSR_I_BIT | PSR_F_BIT | SVC_MODE, r1 @ set SVC, irqs off
+ @ load phys pgd, stack, resume fn
+ ARM( ldmia r0!, {r1, sp, pc} )
+THUMB( ldmia r0!, {r1, r2, r3} )
+THUMB( mov sp, r2 )
+THUMB( bx r3 )
+ENDPROC(cpu_resume)
+
+sleep_save_sp:
+ .rept CONFIG_NR_CPUS
+ .long 0 @ preserve stack phys ptr here
+ .endr
+
+#ifdef CONFIG_SMP
+cpu_logical_index:
+ adr r3, cpu_map_ptr
+ ldr r2, [r3]
+ add r3, r3, r2 @ virt_to_phys(__cpu_logical_map)
+ mov r1, #0
+1:
+ ldr r2, [r3, r1, lsl #2]
+ cmp r2, r0
+ moveq pc, lr
+ add r1, r1, #1
+ b 1b
+
+cpu_map_ptr:
+ .long __cpu_logical_map - .
+#endif