/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * This file contains kexec low-level functions. * * Copyright (C) 2002-2003 Eric Biederman <ebiederm@xmission.com> * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz * PPC44x port. Copyright (C) 2011, IBM Corporation * Author: Suzuki Poulose <suzuki@in.ibm.com> */ #include <linux/objtool.h> #include <asm/reg.h> #include <asm/page.h> #include <asm/mmu.h> #include <asm/ppc_asm.h> #include <asm/kexec.h> .text /* * Must be relocatable PIC code callable as a C function. */ .globl relocate_new_kernel relocate_new_kernel: /* r3 = page_list */ /* r4 = reboot_code_buffer */ /* r5 = start_address */ #ifdef CONFIG_PPC_85xx mr r29, r3 mr r30, r4 mr r31, r5 #define ENTRY_MAPPING_KEXEC_SETUP #include <kernel/85xx_entry_mapping.S> #undef ENTRY_MAPPING_KEXEC_SETUP mr r3, r29 mr r4, r30 mr r5, r31 li r0, 0 #elif defined(CONFIG_44x) /* Save our parameters */ mr r29, r3 mr r30, r4 mr r31, r5 #ifdef CONFIG_PPC_47x /* Check for 47x cores */ mfspr r3,SPRN_PVR srwi r3,r3,16 cmplwi cr0,r3,PVR_476FPE@h beq setup_map_47x cmplwi cr0,r3,PVR_476@h beq setup_map_47x cmplwi cr0,r3,PVR_476_ISS@h beq setup_map_47x #endif /* CONFIG_PPC_47x */ /* * Code for setting up 1:1 mapping for PPC440x for KEXEC * * We cannot switch off the MMU on PPC44x. * So we: * 1) Invalidate all the mappings except the one we are running from. * 2) Create a tmp mapping for our code in the other address space(TS) and * jump to it. Invalidate the entry we started in. * 3) Create a 1:1 mapping for 0-2GiB in chunks of 256M in original TS. * 4) Jump to the 1:1 mapping in original TS. * 5) Invalidate the tmp mapping. * * - Based on the kexec support code for FSL BookE * */ /* * Load the PID with kernel PID (0). * Also load our MSR_IS and TID to MMUCR for TLB search. */ li r3, 0 mtspr SPRN_PID, r3 mfmsr r4 andi. r4,r4,MSR_IS@l beq wmmucr oris r3,r3,PPC44x_MMUCR_STS@h wmmucr: mtspr SPRN_MMUCR,r3 sync /* * Invalidate all the TLB entries except the current entry * where we are running from */ bcl 20,31,$+4 /* Find our address */ 0: mflr r5 /* Make it accessible */ tlbsx r23,0,r5 /* Find entry we are in */ li r4,0 /* Start at TLB entry 0 */ li r3,0 /* Set PAGEID inval value */ 1: cmpw r23,r4 /* Is this our entry? */ beq skip /* If so, skip the inval */ tlbwe r3,r4,PPC44x_TLB_PAGEID /* If not, inval the entry */ skip: addi r4,r4,1 /* Increment */ cmpwi r4,64 /* Are we done? */ bne 1b /* If not, repeat */ isync /* Create a temp mapping and jump to it */ andi. r6, r23, 1 /* Find the index to use */ addi r24, r6, 1 /* r24 will contain 1 or 2 */ mfmsr r9 /* get the MSR */ rlwinm r5, r9, 27, 31, 31 /* Extract the MSR[IS] */ xori r7, r5, 1 /* Use the other address space */ /* Read the current mapping entries */ tlbre r3, r23, PPC44x_TLB_PAGEID tlbre r4, r23, PPC44x_TLB_XLAT tlbre r5, r23, PPC44x_TLB_ATTRIB /* Save our current XLAT entry */ mr r25, r4 /* Extract the TLB PageSize */ li r10, 1 /* r10 will hold PageSize */ rlwinm r11, r3, 0, 24, 27 /* bits 24-27 */ /* XXX: As of now we use 256M, 4K pages */ cmpwi r11, PPC44x_TLB_256M bne tlb_4k rotlwi r10, r10, 28 /* r10 = 256M */ b write_out tlb_4k: cmpwi r11, PPC44x_TLB_4K bne default rotlwi r10, r10, 12 /* r10 = 4K */ b write_out default: rotlwi r10, r10, 10 /* r10 = 1K */ write_out: /* * Write out the tmp 1:1 mapping for this code in other address space * Fixup EPN = RPN , TS=other address space */ insrwi r3, r7, 1, 23 /* Bit 23 is TS for PAGEID field */ /* Write out the tmp mapping entries */ tlbwe r3, r24, PPC44x_TLB_PAGEID tlbwe r4, r24, PPC44x_TLB_XLAT tlbwe r5, r24, PPC44x_TLB_ATTRIB subi r11, r10, 1 /* PageOffset Mask = PageSize - 1 */ not r10, r11 /* Mask for PageNum */ /* Switch to other address space in MSR */ insrwi r9, r7, 1, 26 /* Set MSR[IS] = r7 */ bcl 20,31,$+4 1: mflr r8 addi r8, r8, (2f-1b) /* Find the target offset */ /* Jump to the tmp mapping */ mtspr SPRN_SRR0, r8 mtspr SPRN_SRR1, r9 rfi 2: /* Invalidate the entry we were executing from */ li r3, 0 tlbwe r3, r23, PPC44x_TLB_PAGEID /* attribute fields. rwx for SUPERVISOR mode */ li r5, 0 ori r5, r5, (PPC44x_TLB_SW | PPC44x_TLB_SR | PPC44x_TLB_SX | PPC44x_TLB_G) /* Create 1:1 mapping in 256M pages */ xori r7, r7, 1 /* Revert back to Original TS */ li r8, 0 /* PageNumber */ li r6, 3 /* TLB Index, start at 3 */ next_tlb: rotlwi r3, r8, 28 /* Create EPN (bits 0-3) */ mr r4, r3 /* RPN = EPN */ ori r3, r3, (PPC44x_TLB_VALID | PPC44x_TLB_256M) /* SIZE = 256M, Valid */ insrwi r3, r7, 1, 23 /* Set TS from r7 */ tlbwe r3, r6, PPC44x_TLB_PAGEID /* PageID field : EPN, V, SIZE */ tlbwe r4, r6, PPC44x_TLB_XLAT /* Address translation : RPN */ tlbwe r5, r6, PPC44x_TLB_ATTRIB /* Attributes */ addi r8, r8, 1 /* Increment PN */ addi r6, r6, 1 /* Increment TLB Index */ cmpwi r8, 8 /* Are we done ? */ bne next_tlb isync /* Jump to the new mapping 1:1 */ li r9,0 insrwi r9, r7, 1, 26 /* Set MSR[IS] = r7 */ bcl 20,31,$+4 1: mflr r8 and r8, r8, r11 /* Get our offset within page */ addi r8, r8, (2f-1b) and r5, r25, r10 /* Get our target PageNum */ or r8, r8, r5 /* Target jump address */ mtspr SPRN_SRR0, r8 mtspr SPRN_SRR1, r9 rfi 2: /* Invalidate the tmp entry we used */ li r3, 0 tlbwe r3, r24, PPC44x_TLB_PAGEID sync b ppc44x_map_done #ifdef CONFIG_PPC_47x /* 1:1 mapping for 47x */ setup_map_47x: /* * Load the kernel pid (0) to PID and also to MMUCR[TID]. * Also set the MSR IS->MMUCR STS */ li r3, 0 mtspr SPRN_PID, r3 /* Set PID */ mfmsr r4 /* Get MSR */ andi. r4, r4, MSR_IS@l /* TS=1? */ beq 1f /* If not, leave STS=0 */ oris r3, r3, PPC47x_MMUCR_STS@h /* Set STS=1 */ 1: mtspr SPRN_MMUCR, r3 /* Put MMUCR */ sync /* Find the entry we are running from */ bcl 20,31,$+4 2: mflr r23 tlbsx r23, 0, r23 tlbre r24, r23, 0 /* TLB Word 0 */ tlbre r25, r23, 1 /* TLB Word 1 */ tlbre r26, r23, 2 /* TLB Word 2 */ /* * Invalidates all the tlb entries by writing to 256 RPNs(r4) * of 4k page size in all 4 ways (0-3 in r3). * This would invalidate the entire UTLB including the one we are * running from. However the shadow TLB entries would help us * to continue the execution, until we flush them (rfi/isync). */ addis r3, 0, 0x8000 /* specify the way */ addi r4, 0, 0 /* TLB Word0 = (EPN=0, VALID = 0) */ addi r5, 0, 0 b clear_utlb_entry /* Align the loop to speed things up. from head_44x.S */ .align 6 clear_utlb_entry: tlbwe r4, r3, 0 tlbwe r5, r3, 1 tlbwe r5, r3, 2 addis r3, r3, 0x2000 /* Increment the way */ cmpwi r3, 0 bne clear_utlb_entry addis r3, 0, 0x8000 addis r4, r4, 0x100 /* Increment the EPN */ cmpwi r4, 0 bne clear_utlb_entry /* Create the entries in the other address space */ mfmsr r5 rlwinm r7, r5, 27, 31, 31 /* Get the TS (Bit 26) from MSR */ xori r7, r7, 1 /* r7 = !TS */ insrwi r24, r7, 1, 21 /* Change the TS in the saved TLB word 0 */ /* * write out the TLB entries for the tmp mapping * Use way '0' so that we could easily invalidate it later. */ lis r3, 0x8000 /* Way '0' */ tlbwe r24, r3, 0 tlbwe r25, r3, 1 tlbwe r26, r3, 2 /* Update the msr to the new TS */ insrwi r5, r7, 1, 26 bcl 20,31,$+4 1: mflr r6 addi r6, r6, (2f-1b) mtspr SPRN_SRR0, r6 mtspr SPRN_SRR1, r5 rfi /* * Now we are in the tmp address space. * Create a 1:1 mapping for 0-2GiB in the original TS. */ 2: li r3, 0 li r4, 0 /* TLB Word 0 */ li r5, 0 /* TLB Word 1 */ li r6, 0 ori r6, r6, PPC47x_TLB2_S_RWX /* TLB word 2 */ li r8, 0 /* PageIndex */ xori r7, r7, 1 /* revert back to original TS */ write_utlb: rotlwi r5, r8, 28 /* RPN = PageIndex * 256M */ /* ERPN = 0 as we don't use memory above 2G */ mr r4, r5 /* EPN = RPN */ ori r4, r4, (PPC47x_TLB0_VALID | PPC47x_TLB0_256M) insrwi r4, r7, 1, 21 /* Insert the TS to Word 0 */ tlbwe r4, r3, 0 /* Write out the entries */ tlbwe r5, r3, 1 tlbwe r6, r3, 2 addi r8, r8, 1 cmpwi r8, 8 /* Have we completed ? */ bne write_utlb /* make sure we complete the TLB write up */ isync /* * Prepare to jump to the 1:1 mapping. * 1) Extract page size of the tmp mapping * DSIZ = TLB_Word0[22:27] * 2) Calculate the physical address of the address * to jump to. */ rlwinm r10, r24, 0, 22, 27 cmpwi r10, PPC47x_TLB0_4K li r10, 0x1000 /* r10 = 4k */ beq 0f /* Defaults to 256M */ lis r10, 0x1000 0: bcl 20,31,$+4 1: mflr r4 addi r4, r4, (2f-1b) /* virtual address of 2f */ subi r11, r10, 1 /* offsetmask = Pagesize - 1 */ not r10, r11 /* Pagemask = ~(offsetmask) */ and r5, r25, r10 /* Physical page */ and r6, r4, r11 /* offset within the current page */ or r5, r5, r6 /* Physical address for 2f */ /* Switch the TS in MSR to the original one */ mfmsr r8 insrwi r8, r7, 1, 26 mtspr SPRN_SRR1, r8 mtspr SPRN_SRR0, r5 rfi 2: /* Invalidate the tmp mapping */ lis r3, 0x8000 /* Way '0' */ clrrwi r24, r24, 12 /* Clear the valid bit */ tlbwe r24, r3, 0 tlbwe r25, r3, 1 tlbwe r26, r3, 2 /* Make sure we complete the TLB write and flush the shadow TLB */ isync #endif ppc44x_map_done: /* Restore the parameters */ mr r3, r29 mr r4, r30 mr r5, r31 li r0, 0 #else li r0, 0 /* * Set Machine Status Register to a known status, * switch the MMU off and jump to 1: in a single step. */ mr r8, r0 ori r8, r8, MSR_RI|MSR_ME mtspr SPRN_SRR1, r8 addi r8, r4, 1f - relocate_new_kernel mtspr SPRN_SRR0, r8 sync rfi 1: #endif /* from this point address translation is turned off */ /* and interrupts are disabled */ /* set a new stack at the bottom of our page... */ /* (not really needed now) */ addi r1, r4, KEXEC_CONTROL_PAGE_SIZE - 8 /* for LR Save+Back Chain */ stw r0, 0(r1) /* Do the copies */ li r6, 0 /* checksum */ mr r0, r3 b 1f 0: /* top, read another word for the indirection page */ lwzu r0, 4(r3) 1: /* is it a destination page? (r8) */ rlwinm. r7, r0, 0, 31, 31 /* IND_DESTINATION (1<<0) */ beq 2f rlwinm r8, r0, 0, 0, 19 /* clear kexec flags, page align */ b 0b 2: /* is it an indirection page? (r3) */ rlwinm. r7, r0, 0, 30, 30 /* IND_INDIRECTION (1<<1) */ beq 2f rlwinm r3, r0, 0, 0, 19 /* clear kexec flags, page align */ subi r3, r3, 4 b 0b 2: /* are we done? */ rlwinm. r7, r0, 0, 29, 29 /* IND_DONE (1<<2) */ beq 2f b 3f 2: /* is it a source page? (r9) */ rlwinm. r7, r0, 0, 28, 28 /* IND_SOURCE (1<<3) */ beq 0b rlwinm r9, r0, 0, 0, 19 /* clear kexec flags, page align */ li r7, PAGE_SIZE / 4 mtctr r7 subi r9, r9, 4 subi r8, r8, 4 9: lwzu r0, 4(r9) /* do the copy */ xor r6, r6, r0 stwu r0, 4(r8) dcbst 0, r8 sync icbi 0, r8 bdnz 9b addi r9, r9, 4 addi r8, r8, 4 b 0b 3: /* To be certain of avoiding problems with self-modifying code * execute a serializing instruction here. */ isync sync mfspr r3, SPRN_PIR /* current core we are running on */ mr r4, r5 /* load physical address of chunk called */ /* jump to the entry point, usually the setup routine */ mtlr r5 blrl 1: b 1b relocate_new_kernel_end: .globl relocate_new_kernel_size relocate_new_kernel_size: .long relocate_new_kernel_end - relocate_new_kernel
