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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/powerpc/kernel/swsusp_32.S
Initial import
Diffstat (limited to 'arch/powerpc/kernel/swsusp_32.S')
-rw-r--r--arch/powerpc/kernel/swsusp_32.S350
1 files changed, 350 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/swsusp_32.S b/arch/powerpc/kernel/swsusp_32.S
new file mode 100644
index 000000000..ba4dee3d2
--- /dev/null
+++ b/arch/powerpc/kernel/swsusp_32.S
@@ -0,0 +1,350 @@
+#include <linux/threads.h>
+#include <asm/processor.h>
+#include <asm/page.h>
+#include <asm/cputable.h>
+#include <asm/thread_info.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/mmu.h>
+
+/*
+ * Structure for storing CPU registers on the save area.
+ */
+#define SL_SP 0
+#define SL_PC 4
+#define SL_MSR 8
+#define SL_SDR1 0xc
+#define SL_SPRG0 0x10 /* 4 sprg's */
+#define SL_DBAT0 0x20
+#define SL_IBAT0 0x28
+#define SL_DBAT1 0x30
+#define SL_IBAT1 0x38
+#define SL_DBAT2 0x40
+#define SL_IBAT2 0x48
+#define SL_DBAT3 0x50
+#define SL_IBAT3 0x58
+#define SL_TB 0x60
+#define SL_R2 0x68
+#define SL_CR 0x6c
+#define SL_LR 0x70
+#define SL_R12 0x74 /* r12 to r31 */
+#define SL_SIZE (SL_R12 + 80)
+
+ .section .data
+ .align 5
+
+_GLOBAL(swsusp_save_area)
+ .space SL_SIZE
+
+
+ .section .text
+ .align 5
+
+_GLOBAL(swsusp_arch_suspend)
+
+ lis r11,swsusp_save_area@h
+ ori r11,r11,swsusp_save_area@l
+
+ mflr r0
+ stw r0,SL_LR(r11)
+ mfcr r0
+ stw r0,SL_CR(r11)
+ stw r1,SL_SP(r11)
+ stw r2,SL_R2(r11)
+ stmw r12,SL_R12(r11)
+
+ /* Save MSR & SDR1 */
+ mfmsr r4
+ stw r4,SL_MSR(r11)
+ mfsdr1 r4
+ stw r4,SL_SDR1(r11)
+
+ /* Get a stable timebase and save it */
+1: mftbu r4
+ stw r4,SL_TB(r11)
+ mftb r5
+ stw r5,SL_TB+4(r11)
+ mftbu r3
+ cmpw r3,r4
+ bne 1b
+
+ /* Save SPRGs */
+ mfsprg r4,0
+ stw r4,SL_SPRG0(r11)
+ mfsprg r4,1
+ stw r4,SL_SPRG0+4(r11)
+ mfsprg r4,2
+ stw r4,SL_SPRG0+8(r11)
+ mfsprg r4,3
+ stw r4,SL_SPRG0+12(r11)
+
+ /* Save BATs */
+ mfdbatu r4,0
+ stw r4,SL_DBAT0(r11)
+ mfdbatl r4,0
+ stw r4,SL_DBAT0+4(r11)
+ mfdbatu r4,1
+ stw r4,SL_DBAT1(r11)
+ mfdbatl r4,1
+ stw r4,SL_DBAT1+4(r11)
+ mfdbatu r4,2
+ stw r4,SL_DBAT2(r11)
+ mfdbatl r4,2
+ stw r4,SL_DBAT2+4(r11)
+ mfdbatu r4,3
+ stw r4,SL_DBAT3(r11)
+ mfdbatl r4,3
+ stw r4,SL_DBAT3+4(r11)
+ mfibatu r4,0
+ stw r4,SL_IBAT0(r11)
+ mfibatl r4,0
+ stw r4,SL_IBAT0+4(r11)
+ mfibatu r4,1
+ stw r4,SL_IBAT1(r11)
+ mfibatl r4,1
+ stw r4,SL_IBAT1+4(r11)
+ mfibatu r4,2
+ stw r4,SL_IBAT2(r11)
+ mfibatl r4,2
+ stw r4,SL_IBAT2+4(r11)
+ mfibatu r4,3
+ stw r4,SL_IBAT3(r11)
+ mfibatl r4,3
+ stw r4,SL_IBAT3+4(r11)
+
+#if 0
+ /* Backup various CPU config stuffs */
+ bl __save_cpu_setup
+#endif
+ /* Call the low level suspend stuff (we should probably have made
+ * a stackframe...
+ */
+ bl swsusp_save
+
+ /* Restore LR from the save area */
+ lis r11,swsusp_save_area@h
+ ori r11,r11,swsusp_save_area@l
+ lwz r0,SL_LR(r11)
+ mtlr r0
+
+ blr
+
+
+/* Resume code */
+_GLOBAL(swsusp_arch_resume)
+
+#ifdef CONFIG_ALTIVEC
+ /* Stop pending alitvec streams and memory accesses */
+BEGIN_FTR_SECTION
+ DSSALL
+END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
+#endif
+ sync
+
+ /* Disable MSR:DR to make sure we don't take a TLB or
+ * hash miss during the copy, as our hash table will
+ * for a while be unusable. For .text, we assume we are
+ * covered by a BAT. This works only for non-G5 at this
+ * point. G5 will need a better approach, possibly using
+ * a small temporary hash table filled with large mappings,
+ * disabling the MMU completely isn't a good option for
+ * performance reasons.
+ * (Note that 750's may have the same performance issue as
+ * the G5 in this case, we should investigate using moving
+ * BATs for these CPUs)
+ */
+ mfmsr r0
+ sync
+ rlwinm r0,r0,0,28,26 /* clear MSR_DR */
+ mtmsr r0
+ sync
+ isync
+
+ /* Load ptr the list of pages to copy in r3 */
+ lis r11,(restore_pblist - KERNELBASE)@h
+ ori r11,r11,restore_pblist@l
+ lwz r10,0(r11)
+
+ /* Copy the pages. This is a very basic implementation, to
+ * be replaced by something more cache efficient */
+1:
+ tophys(r3,r10)
+ li r0,256
+ mtctr r0
+ lwz r11,pbe_address(r3) /* source */
+ tophys(r5,r11)
+ lwz r10,pbe_orig_address(r3) /* destination */
+ tophys(r6,r10)
+2:
+ lwz r8,0(r5)
+ lwz r9,4(r5)
+ lwz r10,8(r5)
+ lwz r11,12(r5)
+ addi r5,r5,16
+ stw r8,0(r6)
+ stw r9,4(r6)
+ stw r10,8(r6)
+ stw r11,12(r6)
+ addi r6,r6,16
+ bdnz 2b
+ lwz r10,pbe_next(r3)
+ cmpwi 0,r10,0
+ bne 1b
+
+ /* Do a very simple cache flush/inval of the L1 to ensure
+ * coherency of the icache
+ */
+ lis r3,0x0002
+ mtctr r3
+ li r3, 0
+1:
+ lwz r0,0(r3)
+ addi r3,r3,0x0020
+ bdnz 1b
+ isync
+ sync
+
+ /* Now flush those cache lines */
+ lis r3,0x0002
+ mtctr r3
+ li r3, 0
+1:
+ dcbf 0,r3
+ addi r3,r3,0x0020
+ bdnz 1b
+ sync
+
+ /* Ok, we are now running with the kernel data of the old
+ * kernel fully restored. We can get to the save area
+ * easily now. As for the rest of the code, it assumes the
+ * loader kernel and the booted one are exactly identical
+ */
+ lis r11,swsusp_save_area@h
+ ori r11,r11,swsusp_save_area@l
+ tophys(r11,r11)
+
+#if 0
+ /* Restore various CPU config stuffs */
+ bl __restore_cpu_setup
+#endif
+ /* Restore the BATs, and SDR1. Then we can turn on the MMU.
+ * This is a bit hairy as we are running out of those BATs,
+ * but first, our code is probably in the icache, and we are
+ * writing the same value to the BAT, so that should be fine,
+ * though a better solution will have to be found long-term
+ */
+ lwz r4,SL_SDR1(r11)
+ mtsdr1 r4
+ lwz r4,SL_SPRG0(r11)
+ mtsprg 0,r4
+ lwz r4,SL_SPRG0+4(r11)
+ mtsprg 1,r4
+ lwz r4,SL_SPRG0+8(r11)
+ mtsprg 2,r4
+ lwz r4,SL_SPRG0+12(r11)
+ mtsprg 3,r4
+
+#if 0
+ lwz r4,SL_DBAT0(r11)
+ mtdbatu 0,r4
+ lwz r4,SL_DBAT0+4(r11)
+ mtdbatl 0,r4
+ lwz r4,SL_DBAT1(r11)
+ mtdbatu 1,r4
+ lwz r4,SL_DBAT1+4(r11)
+ mtdbatl 1,r4
+ lwz r4,SL_DBAT2(r11)
+ mtdbatu 2,r4
+ lwz r4,SL_DBAT2+4(r11)
+ mtdbatl 2,r4
+ lwz r4,SL_DBAT3(r11)
+ mtdbatu 3,r4
+ lwz r4,SL_DBAT3+4(r11)
+ mtdbatl 3,r4
+ lwz r4,SL_IBAT0(r11)
+ mtibatu 0,r4
+ lwz r4,SL_IBAT0+4(r11)
+ mtibatl 0,r4
+ lwz r4,SL_IBAT1(r11)
+ mtibatu 1,r4
+ lwz r4,SL_IBAT1+4(r11)
+ mtibatl 1,r4
+ lwz r4,SL_IBAT2(r11)
+ mtibatu 2,r4
+ lwz r4,SL_IBAT2+4(r11)
+ mtibatl 2,r4
+ lwz r4,SL_IBAT3(r11)
+ mtibatu 3,r4
+ lwz r4,SL_IBAT3+4(r11)
+ mtibatl 3,r4
+#endif
+
+BEGIN_MMU_FTR_SECTION
+ li r4,0
+ mtspr SPRN_DBAT4U,r4
+ mtspr SPRN_DBAT4L,r4
+ mtspr SPRN_DBAT5U,r4
+ mtspr SPRN_DBAT5L,r4
+ mtspr SPRN_DBAT6U,r4
+ mtspr SPRN_DBAT6L,r4
+ mtspr SPRN_DBAT7U,r4
+ mtspr SPRN_DBAT7L,r4
+ mtspr SPRN_IBAT4U,r4
+ mtspr SPRN_IBAT4L,r4
+ mtspr SPRN_IBAT5U,r4
+ mtspr SPRN_IBAT5L,r4
+ mtspr SPRN_IBAT6U,r4
+ mtspr SPRN_IBAT6L,r4
+ mtspr SPRN_IBAT7U,r4
+ mtspr SPRN_IBAT7L,r4
+END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
+
+ /* Flush all TLBs */
+ lis r4,0x1000
+1: addic. r4,r4,-0x1000
+ tlbie r4
+ bgt 1b
+ sync
+
+ /* restore the MSR and turn on the MMU */
+ lwz r3,SL_MSR(r11)
+ bl turn_on_mmu
+ tovirt(r11,r11)
+
+ /* Restore TB */
+ li r3,0
+ mttbl r3
+ lwz r3,SL_TB(r11)
+ lwz r4,SL_TB+4(r11)
+ mttbu r3
+ mttbl r4
+
+ /* Kick decrementer */
+ li r0,1
+ mtdec r0
+
+ /* Restore the callee-saved registers and return */
+ lwz r0,SL_CR(r11)
+ mtcr r0
+ lwz r2,SL_R2(r11)
+ lmw r12,SL_R12(r11)
+ lwz r1,SL_SP(r11)
+ lwz r0,SL_LR(r11)
+ mtlr r0
+
+ // XXX Note: we don't really need to call swsusp_resume
+
+ li r3,0
+ blr
+
+/* FIXME:This construct is actually not useful since we don't shut
+ * down the instruction MMU, we could just flip back MSR-DR on.
+ */
+turn_on_mmu:
+ mflr r4
+ mtsrr0 r4
+ mtsrr1 r3
+ sync
+ isync
+ rfi
+