1 files changed, 412 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/52xx/lite5200_sleep.S b/arch/powerpc/platforms/52xx/lite5200_sleep.S
new file mode 100644
index 000000000000..08ab6fefcf7a
--- /dev/null
+++ b/arch/powerpc/platforms/52xx/lite5200_sleep.S
@@ -0,0 +1,412 @@
+#include <asm/reg.h>
+#include <asm/ppc_asm.h>
+#include <asm/processor.h>
+#include <asm/cache.h>
+
+
+#define SDRAM_CTRL	0x104
+#define SC_MODE_EN	(1<<31)
+#define SC_CKE		(1<<30)
+#define SC_REF_EN	(1<<28)
+#define SC_SOFT_PRE	(1<<1)
+
+#define GPIOW_GPIOE	0xc00
+#define GPIOW_DDR	0xc08
+#define GPIOW_DVO	0xc0c
+
+#define CDM_CE		0x214
+#define CDM_SDRAM	(1<<3)
+
+
+/* helpers... beware: r10 and r4 are overwritten */
+#define SAVE_SPRN(reg, addr)		\
+	mfspr	r10, SPRN_##reg;	\
+	stw	r10, ((addr)*4)(r4);
+
+#define LOAD_SPRN(reg, addr)		\
+	lwz	r10, ((addr)*4)(r4);	\
+	mtspr	SPRN_##reg, r10;	\
+	sync;				\
+	isync;
+
+
+	.data
+registers:
+	.space 0x5c*4
+	.text
+
+/* ---------------------------------------------------------------------- */
+/* low-power mode with help of M68HLC908QT1 */
+
+	.globl lite5200_low_power
+lite5200_low_power:
+
+	mr	r7, r3	/* save SRAM va */
+	mr	r8, r4	/* save MBAR va */
+
+	/* setup wakeup address for u-boot at physical location 0x0 */
+	lis	r3, CONFIG_KERNEL_START@h
+	lis	r4, lite5200_wakeup@h
+	ori	r4, r4, lite5200_wakeup@l
+	sub	r4, r4, r3
+	stw	r4, 0(r3)
+
+
+	/*
+	 * save stuff BDI overwrites
+	 * 0xf0 (0xe0->0x100 gets overwritten when BDI connected;
+	 *   even when CONFIG_BDI* is disabled and MMU XLAT commented; heisenbug?))
+	 * WARNING: self-refresh doesn't seem to work when BDI2000 is connected,
+	 *   possibly because BDI sets SDRAM registers before wakeup code does
+	 */
+	lis	r4, registers@h
+	ori	r4, r4, registers@l
+	lwz	r10, 0xf0(r3)
+	stw	r10, (0x1d*4)(r4)
+
+	/* save registers to r4 [destroys r10] */
+	SAVE_SPRN(LR, 0x1c)
+	bl	save_regs
+
+	/* flush caches [destroys r3, r4] */
+	bl	flush_data_cache
+
+
+	/* copy code to sram */
+	mr	r4, r7
+	li	r3, (sram_code_end - sram_code)/4
+	mtctr	r3
+	lis	r3, sram_code@h
+	ori	r3, r3, sram_code@l
+1:
+	lwz	r5, 0(r3)
+	stw	r5, 0(r4)
+	addi	r3, r3, 4
+	addi	r4, r4, 4
+	bdnz	1b
+
+	/* get tb_ticks_per_usec */
+	lis	r3, tb_ticks_per_usec@h
+	lwz	r11, tb_ticks_per_usec@l(r3)
+
+	/* disable I and D caches */
+	mfspr	r3, SPRN_HID0
+	ori	r3, r3, HID0_ICE | HID0_DCE
+	xori	r3, r3, HID0_ICE | HID0_DCE
+	sync; isync;
+	mtspr	SPRN_HID0, r3
+	sync; isync;
+
+	/* jump to sram */
+	mtlr	r7
+	blrl
+	/* doesn't return */
+
+
+sram_code:
+	/* self refresh */
+	lwz	r4, SDRAM_CTRL(r8)
+
+	/* send NOP (precharge) */
+	oris	r4, r4, SC_MODE_EN@h	/* mode_en */
+	stw	r4, SDRAM_CTRL(r8)
+	sync
+
+	ori	r4, r4, SC_SOFT_PRE	/* soft_pre */
+	stw	r4, SDRAM_CTRL(r8)
+	sync
+	xori	r4, r4, SC_SOFT_PRE
+
+	xoris	r4, r4, SC_MODE_EN@h	/* !mode_en */
+	stw	r4, SDRAM_CTRL(r8)
+	sync
+
+	/* delay (for NOP to finish) */
+	li	r12, 1
+	bl	udelay
+
+	/*
+	 * mode_en must not be set when enabling self-refresh
+	 * send AR with CKE low (self-refresh)
+	 */
+	oris	r4, r4, (SC_REF_EN | SC_CKE)@h
+	xoris	r4, r4, (SC_CKE)@h	/* ref_en !cke */
+	stw	r4, SDRAM_CTRL(r8)
+	sync
+
+	/* delay (after !CKE there should be two cycles) */
+	li	r12, 1
+	bl	udelay
+
+	/* disable clock */
+	lwz	r4, CDM_CE(r8)
+	ori	r4, r4, CDM_SDRAM
+	xori	r4, r4, CDM_SDRAM
+	stw	r4, CDM_CE(r8)
+	sync
+
+	/* delay a bit */
+	li	r12, 1
+	bl	udelay
+
+
+	/* turn off with QT chip */
+	li	r4, 0x02
+	stb	r4, GPIOW_GPIOE(r8)	/* enable gpio_wkup1 */
+	sync
+
+	stb	r4, GPIOW_DVO(r8)	/* "output" high */
+	sync
+	stb	r4, GPIOW_DDR(r8)	/* output */
+	sync
+	stb	r4, GPIOW_DVO(r8)	/* output high */
+	sync
+
+	/* 10uS delay */
+	li	r12, 10
+	bl	udelay
+
+	/* turn off */
+	li	r4, 0
+	stb	r4, GPIOW_DVO(r8)	/* output low */
+	sync
+
+	/* wait until we're offline */
+  1:
+	b	1b
+
+
+	/* local udelay in sram is needed */
+  udelay: /* r11 - tb_ticks_per_usec, r12 - usecs, overwrites r13 */
+	mullw	r12, r12, r11
+	mftb	r13	/* start */
+	addi	r12, r13, r12 /* end */
+    1:
+	mftb	r13	/* current */
+	cmp	cr0, r13, r12
+	blt	1b
+	blr
+
+sram_code_end:
+
+
+
+/* uboot jumps here on resume */
+lite5200_wakeup:
+	bl	restore_regs
+
+
+	/* HIDs, MSR */
+	LOAD_SPRN(HID1, 0x19)
+	LOAD_SPRN(HID2, 0x1a)
+
+
+	/* address translation is tricky (see turn_on_mmu) */
+	mfmsr	r10
+	ori	r10, r10, MSR_DR | MSR_IR
+
+
+	mtspr	SPRN_SRR1, r10
+	lis	r10, mmu_on@h
+	ori	r10, r10, mmu_on@l
+	mtspr	SPRN_SRR0, r10
+	sync
+	rfi
+mmu_on:
+	/* kernel offset (r4 is still set from restore_registers) */
+	addis	r4, r4, CONFIG_KERNEL_START@h
+
+
+	/* restore MSR */
+	lwz	r10, (4*0x1b)(r4)
+	mtmsr	r10
+	sync; isync;
+
+	/* invalidate caches */
+	mfspr	r10, SPRN_HID0
+	ori	r5, r10, HID0_ICFI | HID0_DCI
+	mtspr	SPRN_HID0, r5	/* invalidate caches */
+	sync; isync;
+	mtspr	SPRN_HID0, r10
+	sync; isync;
+
+	/* enable caches */
+	lwz	r10, (4*0x18)(r4)
+	mtspr	SPRN_HID0, r10	/* restore (enable caches, DPM) */
+	/* ^ this has to be after address translation set in MSR */
+	sync
+	isync
+
+
+	/* restore 0xf0 (BDI2000) */
+	lis	r3, CONFIG_KERNEL_START@h
+	lwz	r10, (0x1d*4)(r4)
+	stw	r10, 0xf0(r3)
+
+	LOAD_SPRN(LR, 0x1c)
+
+
+	blr
+
+
+/* ---------------------------------------------------------------------- */
+/* boring code: helpers */
+
+/* save registers */
+#define SAVE_BAT(n, addr)		\
+	SAVE_SPRN(DBAT##n##L, addr);	\
+	SAVE_SPRN(DBAT##n##U, addr+1);	\
+	SAVE_SPRN(IBAT##n##L, addr+2);	\
+	SAVE_SPRN(IBAT##n##U, addr+3);
+
+#define SAVE_SR(n, addr)		\
+	mfsr	r10, n;			\
+	stw	r10, ((addr)*4)(r4);
+
+#define SAVE_4SR(n, addr)	\
+	SAVE_SR(n, addr);	\
+	SAVE_SR(n+1, addr+1);	\
+	SAVE_SR(n+2, addr+2);	\
+	SAVE_SR(n+3, addr+3);
+
+save_regs:
+	stw	r0, 0(r4)
+	stw	r1, 0x4(r4)
+	stw	r2, 0x8(r4)
+	stmw	r11, 0xc(r4) /* 0xc -> 0x5f, (0x18*4-1) */
+
+	SAVE_SPRN(HID0, 0x18)
+	SAVE_SPRN(HID1, 0x19)
+	SAVE_SPRN(HID2, 0x1a)
+	mfmsr	r10
+	stw	r10, (4*0x1b)(r4)
+	/*SAVE_SPRN(LR, 0x1c) have to save it before the call */
+	/* 0x1d reserved by 0xf0 */
+	SAVE_SPRN(RPA,   0x1e)
+	SAVE_SPRN(SDR1,  0x1f)
+
+	/* save MMU regs */
+	SAVE_BAT(0, 0x20)
+	SAVE_BAT(1, 0x24)
+	SAVE_BAT(2, 0x28)
+	SAVE_BAT(3, 0x2c)
+	SAVE_BAT(4, 0x30)
+	SAVE_BAT(5, 0x34)
+	SAVE_BAT(6, 0x38)
+	SAVE_BAT(7, 0x3c)
+
+	SAVE_4SR(0, 0x40)
+	SAVE_4SR(4, 0x44)
+	SAVE_4SR(8, 0x48)
+	SAVE_4SR(12, 0x4c)
+
+	SAVE_SPRN(SPRG0, 0x50)
+	SAVE_SPRN(SPRG1, 0x51)
+	SAVE_SPRN(SPRG2, 0x52)
+	SAVE_SPRN(SPRG3, 0x53)
+	SAVE_SPRN(SPRG4, 0x54)
+	SAVE_SPRN(SPRG5, 0x55)
+	SAVE_SPRN(SPRG6, 0x56)
+	SAVE_SPRN(SPRG7, 0x57)
+
+	SAVE_SPRN(IABR,  0x58)
+	SAVE_SPRN(DABR,  0x59)
+	SAVE_SPRN(TBRL,  0x5a)
+	SAVE_SPRN(TBRU,  0x5b)
+
+	blr
+
+
+/* restore registers */
+#define LOAD_BAT(n, addr)		\
+	LOAD_SPRN(DBAT##n##L, addr);	\
+	LOAD_SPRN(DBAT##n##U, addr+1);	\
+	LOAD_SPRN(IBAT##n##L, addr+2);	\
+	LOAD_SPRN(IBAT##n##U, addr+3);
+
+#define LOAD_SR(n, addr)		\
+	lwz	r10, ((addr)*4)(r4);	\
+	mtsr	n, r10;
+
+#define LOAD_4SR(n, addr)	\
+	LOAD_SR(n, addr);	\
+	LOAD_SR(n+1, addr+1);	\
+	LOAD_SR(n+2, addr+2);	\
+	LOAD_SR(n+3, addr+3);
+
+restore_regs:
+	lis	r4, registers@h
+	ori	r4, r4, registers@l
+
+	/* MMU is not up yet */
+	subis	r4, r4, CONFIG_KERNEL_START@h
+
+	lwz	r0, 0(r4)
+	lwz	r1, 0x4(r4)
+	lwz	r2, 0x8(r4)
+	lmw	r11, 0xc(r4)
+
+	/*
+	 * these are a bit tricky
+	 *
+	 * 0x18 - HID0
+	 * 0x19 - HID1
+	 * 0x1a - HID2
+	 * 0x1b - MSR
+	 * 0x1c - LR
+	 * 0x1d - reserved by 0xf0 (BDI2000)
+	 */
+	LOAD_SPRN(RPA,   0x1e);
+	LOAD_SPRN(SDR1,  0x1f);
+
+	/* restore MMU regs */
+	LOAD_BAT(0, 0x20)
+	LOAD_BAT(1, 0x24)
+	LOAD_BAT(2, 0x28)
+	LOAD_BAT(3, 0x2c)
+	LOAD_BAT(4, 0x30)
+	LOAD_BAT(5, 0x34)
+	LOAD_BAT(6, 0x38)
+	LOAD_BAT(7, 0x3c)
+
+	LOAD_4SR(0, 0x40)
+	LOAD_4SR(4, 0x44)
+	LOAD_4SR(8, 0x48)
+	LOAD_4SR(12, 0x4c)
+
+	/* rest of regs */
+	LOAD_SPRN(SPRG0, 0x50);
+	LOAD_SPRN(SPRG1, 0x51);
+	LOAD_SPRN(SPRG2, 0x52);
+	LOAD_SPRN(SPRG3, 0x53);
+	LOAD_SPRN(SPRG4, 0x54);
+	LOAD_SPRN(SPRG5, 0x55);
+	LOAD_SPRN(SPRG6, 0x56);
+	LOAD_SPRN(SPRG7, 0x57);
+
+	LOAD_SPRN(IABR,  0x58);
+	LOAD_SPRN(DABR,  0x59);
+	LOAD_SPRN(TBWL,  0x5a);	/* these two have separate R/W regs */
+	LOAD_SPRN(TBWU,  0x5b);
+
+	blr
+
+
+
+/* cache flushing code. copied from arch/ppc/boot/util.S */
+#define NUM_CACHE_LINES (128*8)
+
+/*
+ * Flush data cache
+ * Do this by just reading lots of stuff into the cache.
+ */
+flush_data_cache:
+	lis	r3,CONFIG_KERNEL_START@h
+	ori	r3,r3,CONFIG_KERNEL_START@l
+	li	r4,NUM_CACHE_LINES
+	mtctr	r4
+1:
+	lwz	r4,0(r3)
+	addi	r3,r3,L1_CACHE_BYTES	/* Next line, please */
+	bdnz	1b
+	blr