linux/arch/sparc64/kernel/ktlb.S
David S. Miller c4bce90ea2 [SPARC64]: Deal with PTE layout differences in SUN4V.
Yes, you heard it right, they changed the PTE layout for
SUN4V.  Ho hum...

This is the simple and inefficient way to support this.
It'll get optimized, don't worry.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 01:12:25 -08:00

236 lines
4.7 KiB
ArmAsm

/* arch/sparc64/kernel/ktlb.S: Kernel mapping TLB miss handling.
*
* Copyright (C) 1995, 1997, 2005 David S. Miller <davem@davemloft.net>
* Copyright (C) 1996 Eddie C. Dost (ecd@brainaid.de)
* Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
* Copyright (C) 1996,98,99 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
*/
#include <linux/config.h>
#include <asm/head.h>
#include <asm/asi.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/tsb.h>
.text
.align 32
kvmap_itlb:
/* g6: TAG TARGET */
mov TLB_TAG_ACCESS, %g4
ldxa [%g4] ASI_IMMU, %g4
/* sun4v_itlb_miss branches here with the missing virtual
* address already loaded into %g4
*/
kvmap_itlb_4v:
kvmap_itlb_nonlinear:
/* Catch kernel NULL pointer calls. */
sethi %hi(PAGE_SIZE), %g5
cmp %g4, %g5
bleu,pn %xcc, kvmap_dtlb_longpath
nop
KERN_TSB_LOOKUP_TL1(%g4, %g6, %g5, %g1, %g2, %g3, kvmap_itlb_load)
kvmap_itlb_tsb_miss:
sethi %hi(LOW_OBP_ADDRESS), %g5
cmp %g4, %g5
blu,pn %xcc, kvmap_itlb_vmalloc_addr
mov 0x1, %g5
sllx %g5, 32, %g5
cmp %g4, %g5
blu,pn %xcc, kvmap_itlb_obp
nop
kvmap_itlb_vmalloc_addr:
KERN_PGTABLE_WALK(%g4, %g5, %g2, kvmap_itlb_longpath)
KTSB_LOCK_TAG(%g1, %g2, %g7)
/* Load and check PTE. */
ldxa [%g5] ASI_PHYS_USE_EC, %g5
brgez,a,pn %g5, kvmap_itlb_longpath
KTSB_STORE(%g1, %g0)
KTSB_WRITE(%g1, %g5, %g6)
/* fallthrough to TLB load */
kvmap_itlb_load:
661: stxa %g5, [%g0] ASI_ITLB_DATA_IN
retry
.section .sun4v_2insn_patch, "ax"
.word 661b
nop
nop
.previous
/* For sun4v the ASI_ITLB_DATA_IN store and the retry
* instruction get nop'd out and we get here to branch
* to the sun4v tlb load code. The registers are setup
* as follows:
*
* %g4: vaddr
* %g5: PTE
* %g6: TAG
*
* The sun4v TLB load wants the PTE in %g3 so we fix that
* up here.
*/
ba,pt %xcc, sun4v_itlb_load
mov %g5, %g3
kvmap_itlb_longpath:
661: rdpr %pstate, %g5
wrpr %g5, PSTATE_AG | PSTATE_MG, %pstate
.section .sun4v_2insn_patch, "ax"
.word 661b
nop
nop
.previous
rdpr %tpc, %g5
ba,pt %xcc, sparc64_realfault_common
mov FAULT_CODE_ITLB, %g4
kvmap_itlb_obp:
OBP_TRANS_LOOKUP(%g4, %g5, %g2, %g3, kvmap_itlb_longpath)
KTSB_LOCK_TAG(%g1, %g2, %g7)
KTSB_WRITE(%g1, %g5, %g6)
ba,pt %xcc, kvmap_itlb_load
nop
kvmap_dtlb_obp:
OBP_TRANS_LOOKUP(%g4, %g5, %g2, %g3, kvmap_dtlb_longpath)
KTSB_LOCK_TAG(%g1, %g2, %g7)
KTSB_WRITE(%g1, %g5, %g6)
ba,pt %xcc, kvmap_dtlb_load
nop
.align 32
kvmap_dtlb:
/* %g6: TAG TARGET */
mov TLB_TAG_ACCESS, %g4
ldxa [%g4] ASI_DMMU, %g4
/* sun4v_dtlb_miss branches here with the missing virtual
* address already loaded into %g4
*/
kvmap_dtlb_4v:
brgez,pn %g4, kvmap_dtlb_nonlinear
nop
sethi %hi(kern_linear_pte_xor), %g2
ldx [%g2 + %lo(kern_linear_pte_xor)], %g2
.globl kvmap_linear_patch
kvmap_linear_patch:
ba,pt %xcc, kvmap_dtlb_load
xor %g2, %g4, %g5
kvmap_dtlb_vmalloc_addr:
KERN_PGTABLE_WALK(%g4, %g5, %g2, kvmap_dtlb_longpath)
KTSB_LOCK_TAG(%g1, %g2, %g7)
/* Load and check PTE. */
ldxa [%g5] ASI_PHYS_USE_EC, %g5
brgez,a,pn %g5, kvmap_dtlb_longpath
KTSB_STORE(%g1, %g0)
KTSB_WRITE(%g1, %g5, %g6)
/* fallthrough to TLB load */
kvmap_dtlb_load:
661: stxa %g5, [%g0] ASI_DTLB_DATA_IN ! Reload TLB
retry
.section .sun4v_2insn_patch, "ax"
.word 661b
nop
nop
.previous
/* For sun4v the ASI_DTLB_DATA_IN store and the retry
* instruction get nop'd out and we get here to branch
* to the sun4v tlb load code. The registers are setup
* as follows:
*
* %g4: vaddr
* %g5: PTE
* %g6: TAG
*
* The sun4v TLB load wants the PTE in %g3 so we fix that
* up here.
*/
ba,pt %xcc, sun4v_dtlb_load
mov %g5, %g3
kvmap_dtlb_nonlinear:
/* Catch kernel NULL pointer derefs. */
sethi %hi(PAGE_SIZE), %g5
cmp %g4, %g5
bleu,pn %xcc, kvmap_dtlb_longpath
nop
KERN_TSB_LOOKUP_TL1(%g4, %g6, %g5, %g1, %g2, %g3, kvmap_dtlb_load)
kvmap_dtlb_tsbmiss:
sethi %hi(MODULES_VADDR), %g5
cmp %g4, %g5
blu,pn %xcc, kvmap_dtlb_longpath
mov (VMALLOC_END >> 24), %g5
sllx %g5, 24, %g5
cmp %g4, %g5
bgeu,pn %xcc, kvmap_dtlb_longpath
nop
kvmap_check_obp:
sethi %hi(LOW_OBP_ADDRESS), %g5
cmp %g4, %g5
blu,pn %xcc, kvmap_dtlb_vmalloc_addr
mov 0x1, %g5
sllx %g5, 32, %g5
cmp %g4, %g5
blu,pn %xcc, kvmap_dtlb_obp
nop
ba,pt %xcc, kvmap_dtlb_vmalloc_addr
nop
kvmap_dtlb_longpath:
661: rdpr %pstate, %g5
wrpr %g5, PSTATE_AG | PSTATE_MG, %pstate
.section .sun4v_2insn_patch, "ax"
.word 661b
nop
nop
.previous
rdpr %tl, %g3
cmp %g3, 1
661: mov TLB_TAG_ACCESS, %g4
ldxa [%g4] ASI_DMMU, %g5
.section .sun4v_2insn_patch, "ax"
.word 661b
mov %g4, %g5
nop
.previous
be,pt %xcc, sparc64_realfault_common
mov FAULT_CODE_DTLB, %g4
ba,pt %xcc, winfix_trampoline
nop