linux/arch/powerpc/kernel/fsl_booke_entry_mapping.S
Jason Yan 2b0e86cc5d powerpc/fsl_booke/32: implement KASLR infrastructure
This patch add support to boot kernel from places other than KERNELBASE.
Since CONFIG_RELOCATABLE has already supported, what we need to do is
map or copy kernel to a proper place and relocate. Freescale Book-E
parts expect lowmem to be mapped by fixed TLB entries(TLB1). The TLB1
entries are not suitable to map the kernel directly in a randomized
region, so we chose to copy the kernel to a proper place and restart to
relocate.

The offset of the kernel was not randomized yet(a fixed 64M is set). We
will randomize it in the next patch.

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Tested-by: Diana Craciun <diana.craciun@nxp.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
[mpe: Use PTRRELOC() in early_init()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-11-13 19:27:40 +11:00

231 lines
5.4 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
/* 1. Find the index of the entry we're executing in */
bl invstr /* Find our address */
invstr: mflr r6 /* Make it accessible */
mfmsr r7
rlwinm r4,r7,27,31,31 /* extract MSR[IS] */
mfspr r7, SPRN_PID0
slwi r7,r7,16
or r7,r7,r4
mtspr SPRN_MAS6,r7
tlbsx 0,r6 /* search MSR[IS], SPID=PID0 */
mfspr r7,SPRN_MAS1
andis. r7,r7,MAS1_VALID@h
bne match_TLB
mfspr r7,SPRN_MMUCFG
rlwinm r7,r7,21,28,31 /* extract MMUCFG[NPIDS] */
cmpwi r7,3
bne match_TLB /* skip if NPIDS != 3 */
mfspr r7,SPRN_PID1
slwi r7,r7,16
or r7,r7,r4
mtspr SPRN_MAS6,r7
tlbsx 0,r6 /* search MSR[IS], SPID=PID1 */
mfspr r7,SPRN_MAS1
andis. r7,r7,MAS1_VALID@h
bne match_TLB
mfspr r7, SPRN_PID2
slwi r7,r7,16
or r7,r7,r4
mtspr SPRN_MAS6,r7
tlbsx 0,r6 /* Fall through, we had to match */
match_TLB:
mfspr r7,SPRN_MAS0
rlwinm r3,r7,16,20,31 /* Extract MAS0(Entry) */
mfspr r7,SPRN_MAS1 /* Insure IPROT set */
oris r7,r7,MAS1_IPROT@h
mtspr SPRN_MAS1,r7
tlbwe
/* 2. Invalidate all entries except the entry we're executing in */
mfspr r9,SPRN_TLB1CFG
andi. r9,r9,0xfff
li r6,0 /* Set Entry counter to 0 */
1: lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */
rlwimi r7,r6,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r6) */
mtspr SPRN_MAS0,r7
tlbre
mfspr r7,SPRN_MAS1
rlwinm r7,r7,0,2,31 /* Clear MAS1 Valid and IPROT */
cmpw r3,r6
beq skpinv /* Dont update the current execution TLB */
mtspr SPRN_MAS1,r7
tlbwe
isync
skpinv: addi r6,r6,1 /* Increment */
cmpw r6,r9 /* Are we done? */
bne 1b /* If not, repeat */
/* Invalidate TLB0 */
li r6,0x04
tlbivax 0,r6
TLBSYNC
/* Invalidate TLB1 */
li r6,0x0c
tlbivax 0,r6
TLBSYNC
/* 3. Setup a temp mapping and jump to it */
andi. r5, r3, 0x1 /* Find an entry not used and is non-zero */
addi r5, r5, 0x1
lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */
rlwimi r7,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r3) */
mtspr SPRN_MAS0,r7
tlbre
/* grab and fixup the RPN */
mfspr r6,SPRN_MAS1 /* extract MAS1[SIZE] */
rlwinm r6,r6,25,27,31
li r8,-1
addi r6,r6,10
slw r6,r8,r6 /* convert to mask */
bl 1f /* Find our address */
1: mflr r7
mfspr r8,SPRN_MAS3
#ifdef CONFIG_PHYS_64BIT
mfspr r23,SPRN_MAS7
#endif
and r8,r6,r8
subfic r9,r6,-4096
and r9,r9,r7
or r25,r8,r9
ori r8,r25,(MAS3_SX|MAS3_SW|MAS3_SR)
/* Just modify the entry ID and EPN for the temp mapping */
lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */
rlwimi r7,r5,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r5) */
mtspr SPRN_MAS0,r7
xori r6,r4,1 /* Setup TMP mapping in the other Address space */
slwi r6,r6,12
oris r6,r6,(MAS1_VALID|MAS1_IPROT)@h
ori r6,r6,(MAS1_TSIZE(BOOK3E_PAGESZ_4K))@l
mtspr SPRN_MAS1,r6
mfspr r6,SPRN_MAS2
li r7,0 /* temp EPN = 0 */
rlwimi r7,r6,0,20,31
mtspr SPRN_MAS2,r7
mtspr SPRN_MAS3,r8
tlbwe
xori r6,r4,1
slwi r6,r6,5 /* setup new context with other address space */
bl 1f /* Find our address */
1: mflr r9
rlwimi r7,r9,0,20,31
addi r7,r7,(2f - 1b)
mtspr SPRN_SRR0,r7
mtspr SPRN_SRR1,r6
rfi
2:
/* 4. Clear out PIDs & Search info */
li r6,0
mtspr SPRN_MAS6,r6
mtspr SPRN_PID0,r6
mfspr r7,SPRN_MMUCFG
rlwinm r7,r7,21,28,31 /* extract MMUCFG[NPIDS] */
cmpwi r7,3
bne 2f /* skip if NPIDS != 3 */
mtspr SPRN_PID1,r6
mtspr SPRN_PID2,r6
/* 5. Invalidate mapping we started in */
2:
lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */
rlwimi r7,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r3) */
mtspr SPRN_MAS0,r7
tlbre
mfspr r6,SPRN_MAS1
rlwinm r6,r6,0,2,0 /* clear IPROT */
mtspr SPRN_MAS1,r6
tlbwe
/* Invalidate TLB1 */
li r9,0x0c
tlbivax 0,r9
TLBSYNC
#if defined(ENTRY_MAPPING_BOOT_SETUP)
/* 6. Setup kernstart_virt_addr mapping in TLB1[0] */
lis r6,0x1000 /* Set MAS0(TLBSEL) = TLB1(1), ESEL = 0 */
mtspr SPRN_MAS0,r6
lis r6,(MAS1_VALID|MAS1_IPROT)@h
ori r6,r6,(MAS1_TSIZE(BOOK3E_PAGESZ_64M))@l
mtspr SPRN_MAS1,r6
lis r6,MAS2_EPN_MASK(BOOK3E_PAGESZ_64M)@h
ori r6,r6,MAS2_EPN_MASK(BOOK3E_PAGESZ_64M)@l
and r6,r6,r20
ori r6,r6,MAS2_M_IF_NEEDED@l
mtspr SPRN_MAS2,r6
mtspr SPRN_MAS3,r8
tlbwe
/* 7. Jump to kernstart_virt_addr mapping */
mr r6,r20
#elif defined(ENTRY_MAPPING_KEXEC_SETUP)
/*
* 6. Setup a 1:1 mapping in TLB1. Esel 0 is unsued, 1 or 2 contains the tmp
* mapping so we start at 3. We setup 8 mappings, each 256MiB in size. This
* will cover the first 2GiB of memory.
*/
lis r10, (MAS1_VALID|MAS1_IPROT)@h
ori r10,r10, (MAS1_TSIZE(BOOK3E_PAGESZ_256M))@l
li r11, 0
li r0, 8
mtctr r0
next_tlb_setup:
addi r0, r11, 3
rlwinm r0, r0, 16, 4, 15 // Compute esel
rlwinm r9, r11, 28, 0, 3 // Compute [ER]PN
oris r0, r0, (MAS0_TLBSEL(1))@h
mtspr SPRN_MAS0,r0
mtspr SPRN_MAS1,r10
mtspr SPRN_MAS2,r9
ori r9, r9, (MAS3_SX|MAS3_SW|MAS3_SR)
mtspr SPRN_MAS3,r9
tlbwe
addi r11, r11, 1
bdnz+ next_tlb_setup
/* 7. Jump to our 1:1 mapping */
mr r6, r25
#else
#error You need to specify the mapping or not use this at all.
#endif
lis r7,MSR_KERNEL@h
ori r7,r7,MSR_KERNEL@l
bl 1f /* Find our address */
1: mflr r9
rlwimi r6,r9,0,20,31
addi r6,r6,(2f - 1b)
mtspr SPRN_SRR0,r6
mtspr SPRN_SRR1,r7
rfi /* start execution out of TLB1[0] entry */
/* 8. Clear out the temp mapping */
2: lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */
rlwimi r7,r5,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r5) */
mtspr SPRN_MAS0,r7
tlbre
mfspr r8,SPRN_MAS1
rlwinm r8,r8,0,2,0 /* clear IPROT */
mtspr SPRN_MAS1,r8
tlbwe
/* Invalidate TLB1 */
li r9,0x0c
tlbivax 0,r9
TLBSYNC