/* SPDX-License-Identifier: GPL-2.0 */ #include #include #include #include #include #include #include #include #include /* * 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