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-rw-r--r--arch/powerpc/kexec/relocate_32.S500
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diff --git a/arch/powerpc/kexec/relocate_32.S b/arch/powerpc/kexec/relocate_32.S
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+++ b/arch/powerpc/kexec/relocate_32.S
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+/* 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 <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,$+4
+1: mflr r6
+ addi r6, r6, (2f-1b)
+
+ mtspr SPRN_SRR0, r6
+ mtspr SPRN_SRR1, r5
+ rfi
+
+ /*
+ * Now we are in the tmp address space.
+ * Create a 1:1 mapping for 0-2GiB in the original TS.
+ */
+2:
+ li r3, 0
+ li r4, 0 /* TLB Word 0 */
+ li r5, 0 /* TLB Word 1 */
+ li r6, 0
+ ori r6, r6, PPC47x_TLB2_S_RWX /* TLB word 2 */
+
+ li r8, 0 /* PageIndex */
+
+ xori r7, r7, 1 /* revert back to original TS */
+
+write_utlb:
+ rotlwi r5, r8, 28 /* RPN = PageIndex * 256M */
+ /* ERPN = 0 as we don't use memory above 2G */
+
+ mr r4, r5 /* EPN = RPN */
+ ori r4, r4, (PPC47x_TLB0_VALID | PPC47x_TLB0_256M)
+ insrwi r4, r7, 1, 21 /* Insert the TS to Word 0 */
+
+ tlbwe r4, r3, 0 /* Write out the entries */
+ tlbwe r5, r3, 1
+ tlbwe r6, r3, 2
+ addi r8, r8, 1
+ cmpwi r8, 8 /* Have we completed ? */
+ bne write_utlb
+
+ /* make sure we complete the TLB write up */
+ isync
+
+ /*
+ * Prepare to jump to the 1:1 mapping.
+ * 1) Extract page size of the tmp mapping
+ * DSIZ = TLB_Word0[22:27]
+ * 2) Calculate the physical address of the address
+ * to jump to.
+ */
+ rlwinm r10, r24, 0, 22, 27
+
+ cmpwi r10, PPC47x_TLB0_4K
+ bne 0f
+ li r10, 0x1000 /* r10 = 4k */
+ bl 1f
+
+0:
+ /* Defaults to 256M */
+ lis r10, 0x1000
+
+ bcl 20,31,$+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