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Diffstat (limited to '')
-rw-r--r-- | arch/powerpc/platforms/52xx/lite5200_sleep.S | 415 |
1 files changed, 415 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 000000000..afee8b151 --- /dev/null +++ b/arch/powerpc/platforms/52xx/lite5200_sleep.S @@ -0,0 +1,415 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#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_SWITCH 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 */ + add 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 +_ASM_NOKPROBE_SYMBOL(lite5200_wakeup) + + +/* ---------------------------------------------------------------------- */ +/* 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 +_ASM_NOKPROBE_SYMBOL(restore_regs) + + + +/* 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 |