powerpc: Move swsusp.S over to arch/powerpc

... and rename it to swsusp_32.S, since it's 32-bit only at this stage.

Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 349 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/swsusp_32.S b/arch/powerpc/kernel/swsusp_32.S
new file mode 100644
index 000000000000..69773cc1a85f
--- /dev/null
+++ b/arch/powerpc/kernel/swsusp_32.S
@@ -0,0 +1,349 @@
+#include <linux/config.h>
+#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>
+
+
+/*
+ * 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)
+
+	/* Stop pending alitvec streams and memory accesses */
+BEGIN_FTR_SECTION
+	DSSALL
+END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
+ 	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 unuseable. 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,(pagedir_nosave - KERNELBASE)@h
+	ori	r11,r11,pagedir_nosave@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_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_FTR_SECTION_IFSET(CPU_FTR_HAS_HIGH_BATS)
+
+	/* Flush all TLBs */
+	lis	r4,0x1000
+1:	addic.	r4,r4,-0x1000
+	tlbie	r4
+	blt	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
+