/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* This file contains kexec low-level functions.
*
* Copyright (C) 2002-2003 Eric Biederman <[email protected]>
* GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
* PPC44x port. Copyright (C) 2011, IBM Corporation
* Author: Suzuki Poulose <[email protected]>
*/
#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,$+4
1: mflr r6
addi r6, r6, (2f-1b)
mtspr SPRN_SRR0, r6
mtspr SPRN_SRR1, r5
rfi
/*
* Now we are in the tmp address space.
* Create a 1:1 mapping for 0-2GiB in the original TS.
*/
2:
li r3, 0
li r4, 0 /* TLB Word 0 */
li r5, 0 /* TLB Word 1 */
li r6, 0
ori r6, r6, PPC47x_TLB2_S_RWX /* TLB word 2 */
li r8, 0 /* PageIndex */
xori r7, r7, 1 /* revert back to original TS */
write_utlb:
rotlwi r5, r8, 28 /* RPN = PageIndex * 256M */
/* ERPN = 0 as we don't use memory above 2G */
mr r4, r5 /* EPN = RPN */
ori r4, r4, (PPC47x_TLB0_VALID | PPC47x_TLB0_256M)
insrwi r4, r7, 1, 21 /* Insert the TS to Word 0 */
tlbwe r4, r3, 0 /* Write out the entries */
tlbwe r5, r3, 1
tlbwe r6, r3, 2
addi r8, r8, 1
cmpwi r8, 8 /* Have we completed ? */
bne write_utlb
/* make sure we complete the TLB write up */
isync
/*
* Prepare to jump to the 1:1 mapping.
* 1) Extract page size of the tmp mapping
* DSIZ = TLB_Word0[22:27]
* 2) Calculate the physical address of the address
* to jump to.
*/
rlwinm r10, r24, 0, 22, 27
cmpwi r10, PPC47x_TLB0_4K
bne 0f
li r10, 0x1000 /* r10 = 4k */
ANNOTATE_INTRA_FUNCTION_CALL
bl 1f
0:
/* Defaults to 256M */
lis r10, 0x1000
bcl 20,31,$+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
Codebase Browser
linux