linux_dsm_epyc7002/arch/powerpc/kernel/swsusp_32.S
Christophe Leroy 5f32e8361c powerpc/32: Blacklist functions running with MMU disabled for kprobe
kprobe does not handle events happening in real mode, all
functions running with MMU disabled have to be blacklisted.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/3bf57066d05518644dee0840af69d36ab5086729.1585670437.git.christophe.leroy@c-s.fr
2020-06-02 20:59:11 +10:00

412 lines
8.1 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
#include <linux/threads.h>
#include <asm/processor.h>
#include <asm/page.h>
#include <asm/cputable.h>
#include <asm/thread_info.h>
#include <asm/ppc_asm.h>
#include <asm/asm-offsets.h>
#include <asm/mmu.h>
#include <asm/feature-fixups.h>
/*
* 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_DBAT4 0x60
#define SL_IBAT4 0x68
#define SL_DBAT5 0x70
#define SL_IBAT5 0x78
#define SL_DBAT6 0x80
#define SL_IBAT6 0x88
#define SL_DBAT7 0x90
#define SL_IBAT7 0x98
#define SL_TB 0xa0
#define SL_R2 0xa8
#define SL_CR 0xac
#define SL_LR 0xb0
#define SL_R12 0xb4 /* 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)
BEGIN_MMU_FTR_SECTION
mfspr r4,SPRN_DBAT4U
stw r4,SL_DBAT4(r11)
mfspr r4,SPRN_DBAT4L
stw r4,SL_DBAT4+4(r11)
mfspr r4,SPRN_DBAT5U
stw r4,SL_DBAT5(r11)
mfspr r4,SPRN_DBAT5L
stw r4,SL_DBAT5+4(r11)
mfspr r4,SPRN_DBAT6U
stw r4,SL_DBAT6(r11)
mfspr r4,SPRN_DBAT6L
stw r4,SL_DBAT6+4(r11)
mfspr r4,SPRN_DBAT7U
stw r4,SL_DBAT7(r11)
mfspr r4,SPRN_DBAT7L
stw r4,SL_DBAT7+4(r11)
mfspr r4,SPRN_IBAT4U
stw r4,SL_IBAT4(r11)
mfspr r4,SPRN_IBAT4L
stw r4,SL_IBAT4+4(r11)
mfspr r4,SPRN_IBAT5U
stw r4,SL_IBAT5(r11)
mfspr r4,SPRN_IBAT5L
stw r4,SL_IBAT5+4(r11)
mfspr r4,SPRN_IBAT6U
stw r4,SL_IBAT6(r11)
mfspr r4,SPRN_IBAT6L
stw r4,SL_IBAT6+4(r11)
mfspr r4,SPRN_IBAT7U
stw r4,SL_IBAT7(r11)
mfspr r4,SPRN_IBAT7L
stw r4,SL_IBAT7+4(r11)
END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
#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
BEGIN_MMU_FTR_SECTION
lwz r4,SL_DBAT4(r11)
mtspr SPRN_DBAT4U,r4
lwz r4,SL_DBAT4+4(r11)
mtspr SPRN_DBAT4L,r4
lwz r4,SL_DBAT5(r11)
mtspr SPRN_DBAT5U,r4
lwz r4,SL_DBAT5+4(r11)
mtspr SPRN_DBAT5L,r4
lwz r4,SL_DBAT6(r11)
mtspr SPRN_DBAT6U,r4
lwz r4,SL_DBAT6+4(r11)
mtspr SPRN_DBAT6L,r4
lwz r4,SL_DBAT7(r11)
mtspr SPRN_DBAT7U,r4
lwz r4,SL_DBAT7+4(r11)
mtspr SPRN_DBAT7L,r4
lwz r4,SL_IBAT4(r11)
mtspr SPRN_IBAT4U,r4
lwz r4,SL_IBAT4+4(r11)
mtspr SPRN_IBAT4L,r4
lwz r4,SL_IBAT5(r11)
mtspr SPRN_IBAT5U,r4
lwz r4,SL_IBAT5+4(r11)
mtspr SPRN_IBAT5L,r4
lwz r4,SL_IBAT6(r11)
mtspr SPRN_IBAT6U,r4
lwz r4,SL_IBAT6+4(r11)
mtspr SPRN_IBAT6L,r4
lwz r4,SL_IBAT7(r11)
mtspr SPRN_IBAT7U,r4
lwz r4,SL_IBAT7+4(r11)
mtspr SPRN_IBAT7L,r4
END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
#endif
/* 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
_ASM_NOKPROBE_SYMBOL(swsusp_arch_resume)
/* 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
_ASM_NOKPROBE_SYMBOL(turn_on_mmu)