| /* SPDX-License-Identifier: GPL-2.0 */ |
| #include <linux/linkage.h> |
| |
| #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 */ |
| SYM_FUNC_START_LOCAL(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 |
| SYM_FUNC_END(udelay) |
| |
| 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); |
| |
| SYM_FUNC_START_LOCAL(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 |
| SYM_FUNC_END(save_regs) |
| |
| |
| /* 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); |
| |
| SYM_FUNC_START_LOCAL(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) |
| SYM_FUNC_END(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. |
| */ |
| SYM_FUNC_START_LOCAL(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 |
| SYM_FUNC_END(flush_data_cache) |