/*
* ppc64 MMU hashtable management routines
*
* (c) Copyright IBM Corp. 2003, 2005
*
* Maintained by: Benjamin Herrenschmidt
* <benh@kernel.crashing.org>
*
* This file is covered by the GNU Public Licence v2 as
* described in the kernel's COPYING file.
*/
#include <asm/reg.h>
#include <asm/pgtable.h>
#include <asm/mmu.h>
#include <asm/page.h>
#include <asm/types.h>
#include <asm/ppc_asm.h>
#include <asm/asm-offsets.h>
#include <asm/cputable.h>
.text
/*
* Stackframe:
*
* +-> Back chain (SP + 256)
* | General register save area (SP + 112)
* | Parameter save area (SP + 48)
* | TOC save area (SP + 40)
* | link editor doubleword (SP + 32)
* | compiler doubleword (SP + 24)
* | LR save area (SP + 16)
* | CR save area (SP + 8)
* SP ---> +-- Back chain (SP + 0)
*/
#ifndef CONFIG_PPC_64K_PAGES
/*****************************************************************************
* *
* 4K SW & 4K HW pages implementation *
* *
*****************************************************************************/
/*
* _hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
* pte_t *ptep, unsigned long trap, int local, int ssize)
*
* Adds a 4K page to the hash table in a segment of 4K pages only
*/
_GLOBAL(__hash_page_4K)
mflr r0
std r0,16(r1)
stdu r1,-STACKFRAMESIZE(r1)
/* Save all params that we need after a function call */
std r6,STK_PARAM(R6)(r1)
std r8,STK_PARAM(R8)(r1)
std r9,STK_PARAM(R9)(r1)
/* Save non-volatile registers.
* r31 will hold "old PTE"
* r30 is "new PTE"
* r29 is vpn
* r28 is a hash value
* r27 is hashtab mask (maybe dynamic patched instead ?)
*/
std r27,STK_REG(R27)(r1)
std r28,STK_REG(R28)(r1)
std r29,STK_REG(R29)(r1)
std r30,STK_REG(R30)(r1)
std r31,STK_REG(R31)(r1)
/* Step 1:
*
* Check permissions, atomically mark the linux PTE busy
* and hashed.
*/
1:
ldarx r31,0,r6
/* Check access rights (access & ~(pte_val(*ptep))) */
andc. r0,r4,r31
bne- htab_wrong_access
/* Check if PTE is busy */
andi. r0,r31,_PAGE_BUSY
/* If so, just bail out and refault if needed. Someone else
* is changing this PTE anyway and might hash it.
*/
bne- htab_bail_ok
/* Prepare new PTE value (turn access RW into DIRTY, then
* add BUSY,HASHPTE and ACCESSED)
*/
rlwinm r30,r4,32-9+7,31-7,31-7 /* _PAGE_RW -> _PAGE_DIRTY */
or r30,r30,r31
ori r30,r30,_PAGE_BUSY | _PAGE_ACCESSED | _PAGE_HASHPTE
/* Write the linux PTE atomically (setting busy) */
stdcx. r30,0,r6
bne- 1b
isync
/* Step 2:
*
* Insert/Update the HPTE in the hash table. At this point,
* r4 (access) is re-useable, we use it for the new HPTE flags
*/
BEGIN_FTR_SECTION
cmpdi r9,0 /* check segment size */
bne 3f
END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT)
/* Calc vpn and put it in r29 */
sldi r29,r5,SID_SHIFT - VPN_SHIFT
rldicl r28,r3,64 - VPN_SHIFT,64 - (SID_SHIFT - VPN_SHIFT)
or r29,r28,r29
/*
* Calculate hash value for primary slot and store it in r28
* r3 = va, r5 = vsid
* r0 = (va >> 12) & ((1ul << (28 - 12)) -1)
*/
rldicl r0,r3,64-12,48
xor r28,r5,r0 /* hash */
b 4f
3: /* Calc vpn and put it in r29 */
sldi r29,r5,SID_SHIFT_1T - VPN_SHIFT
rldicl r28,r3,64 - VPN_SHIFT,64 - (SID_SHIFT_1T - VPN_SHIFT)
or r29,r28,r29
/*
* calculate hash value for primary slot and
* store it in r28 for 1T segment
* r3 = va, r5 = vsid
*/
sldi r28,r5,25 /* vsid << 25 */
/* r0 = (va >> 12) & ((1ul << (40 - 12)) -1) */
rldicl r0,r3,64-12,36
xor r28,r28,r5 /* vsid ^ ( vsid << 25) */
xor r28,r28,r0 /* hash */
/* Convert linux PTE bits into HW equivalents */
4: andi. r3,r30,0x1fe /* Get basic set of flags */
xori r3,r3,HPTE_R_N /* _PAGE_EXEC -> NOEXEC */
rlwinm r0,r30,32-9+1,30,30 /* _PAGE_RW -> _PAGE_USER (r0) */
rlwinm r4,r30,32-7+1,30,30 /* _PAGE_DIRTY -> _PAGE_USER (r4) */
and r0,r0,r4 /* _PAGE_RW & _PAGE_DIRTY ->r0 bit 30*/
andc r0,r30,r0 /* r0 = pte & ~r0 */
rlwimi r3,r0,32-1,31,31 /* Insert result into PP lsb */
/*
* Always add "C" bit for perf. Memory coherence is always enabled
*/
ori r3,r3,HPTE_R_C | HPTE_R_M
/* We eventually do the icache sync here (maybe inline that
* code rather than call a C function...)
*/
BEGIN_FTR_SECTION
mr r4,r30
mr r5,r7
bl hash_page_do_lazy_icache
END_FTR_SECTION(CPU_FTR_NOEXECUTE|CPU_FTR_COHERENT_ICACHE, CPU_FTR_NOEXECUTE)
/* At this point, r3 contains new PP bits, save them in
* place of "access" in the param area (sic)
*/
std r3,STK_PARAM(R4)(r1)
/* Get htab_hash_mask */
ld r4,htab_hash_mask@got(2)
ld r27,0(r4) /* htab_hash_mask -> r27 */
/* Check if we may already be in the hashtable, in this case, we
* go to out-of-line code to try to modify the HPTE
*/
andi. r0,r31,_PAGE_HASHPTE
bne htab_modify_pte
htab_insert_pte:
/* Clear hpte bits in new pte (we also clear BUSY btw) and
* add _PAGE_HASHPTE
*/
lis r0,_PAGE_HPTEFLAGS@h
ori r0,r0,_PAGE_HPTEFLAGS@l
andc r30,r30,r0
ori r30,r30,_PAGE_HASHPTE
/* physical address r5 */
rldicl r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
sldi r5,r5,PAGE_SHIFT
/* Calculate primary group hash */
and r0,r28,r27
rldicr r3,r0,3,63-3 /* r3 = (hash & mask) << 3 */
/* Call ppc_md.hpte_insert */
ld r6,STK_PARAM(R4)(r1) /* Retrieve new pp bits */
mr r4,r29 /* Retrieve vpn */
li r7,0 /* !bolted, !secondary */
li r8,MMU_PAGE_4K /* page size */
li r9,MMU_PAGE_4K /* actual page size */
ld r10,STK_PARAM(R9)(r1) /* segment size */
.globl htab_call_hpte_insert1
htab_call_hpte_insert1:
bl . /* Patched by htab_finish_init() */
cmpdi 0,r3,0
bge htab_pte_insert_ok /* Insertion successful */
cmpdi 0,r3,-2 /* Critical failure */
beq- htab_pte_insert_failure
/* Now try secondary slot */
/* physical address r5 */
rldicl r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
sldi r5,r5,PAGE_SHIFT
/* Calculate secondary group hash */
andc r0,r27,r28
rldicr r3,r0,3,63-3 /* r0 = (~hash & mask) << 3 */
/* Call ppc_md.hpte_insert */
ld r6,STK_PARAM(R4)(r1) /* Retrieve new pp bits */
mr r4,r29 /* Retrieve vpn */
li r7,HPTE_V_SECONDARY /* !bolted, secondary */
li r8,MMU_PAGE_4K /* page size */
li r9,MMU_PAGE_4K /* actual page size */
ld r10,STK_PARAM(R9)(r1) /* segment size */
.globl htab_call_hpte_insert2
htab_call_hpte_insert2:
bl . /* Patched by htab_finish_init() */
cmpdi 0,r3,0
bge+ htab_pte_insert_ok /* Insertion successful */
cmpdi 0,r3,-2 /* Critical failure */
beq- htab_pte_insert_failure
/* Both are full, we need to evict something */
mftb r0
/* Pick a random group based on TB */
andi. r0,r0,1
mr r5,r28
bne 2f
not r5,r5
2: and r0,r5,r27
rldicr r3,r0,3,63-3 /* r0 = (hash & mask) << 3 */
/* Call ppc_md.hpte_remove */
.globl htab_call_hpte_remove
htab_call_hpte_remove:
bl . /* Patched by htab_finish_init() */
/* Try all again */
b htab_insert_pte
htab_bail_ok:
li r3,0
b htab_bail
htab_pte_insert_ok:
/* Insert slot number & secondary bit in PTE */
rldimi r30,r3,12,63-15
/* Write out the PTE with a normal write
* (maybe add eieio may be good still ?)
*/
htab_write_out_pte:
ld r6,STK_PARAM(R6)(r1)
std r30,0(r6)
li r3, 0
htab_bail:
ld r27,STK_REG(R27)(r1)
ld r28,STK_REG(R28)(r1)
ld r29,STK_REG(R29)(r1)
ld r30,STK_REG(R30)(r1)
ld r31,STK_REG(R31)(r1)
addi r1,r1,STACKFRAMESIZE
ld r0,16(r1)
mtlr r0
blr
htab_modify_pte:
/* Keep PP bits in r4 and slot idx from the PTE around in r3 */
mr r4,r3
rlwinm r3,r31,32-12,29,31
/* Secondary group ? if yes, get a inverted hash value */
mr r5,r28
andi. r0,r31,_PAGE_SECONDARY
beq 1f
not r5,r5
1:
/* Calculate proper slot value for ppc_md.hpte_updatepp */
and r0,r5,r27
rldicr r0,r0,3,63-3 /* r0 = (hash & mask) << 3 */
add r3,r0,r3 /* add slot idx */
/* Call ppc_md.hpte_updatepp */
mr r5,r29 /* vpn */
li r6,MMU_PAGE_4K /* base page size */
li r7,MMU_PAGE_4K /* actual page size */
ld r8,STK_PARAM(R9)(r1) /* segment size */
ld r9,STK_PARAM(R8)(r1) /* get "local" param */
.globl htab_call_hpte_updatepp
htab_call_hpte_updatepp:
bl . /* Patched by htab_finish_init() */
/* if we failed because typically the HPTE wasn't really here
* we try an insertion.
*/
cmpdi 0,r3,-1
beq- htab_insert_pte
/* Clear the BUSY bit and Write out the PTE */
li r0,_PAGE_BUSY
andc r30,r30,r0
b htab_write_out_pte
htab_wrong_access:
/* Bail out clearing reservation */
stdcx. r31,0,r6
li r3,1
b htab_bail
htab_pte_insert_failure:
/* Bail out restoring old PTE */
ld r6,STK_PARAM(R6)(r1)
std r31,0(r6)
li r3,-1
b htab_bail
#else /* CONFIG_PPC_64K_PAGES */
/*****************************************************************************
* *
* 64K SW & 4K or 64K HW in a 4K segment pages implementation *
* *
*****************************************************************************/
/* _hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
* pte_t *ptep, unsigned long trap, int local, int ssize,
* int subpg_prot)
*/
/*
* For now, we do NOT implement Admixed pages
*/
_GLOBAL(__hash_page_4K)
mflr r0
std r0,16(r1)
stdu r1,-STACKFRAMESIZE(r1)
/* Save all params that we need after a function call */
std r6,STK_PARAM(R6)(r1)
std r8,STK_PARAM(R8)(r1)
std r9,STK_PARAM(R9)(r1)
/* Save non-volatile registers.
* r31 will hold "old PTE"
* r30 is "new PTE"
* r29 is vpn
* r28 is a hash value
* r27 is hashtab mask (maybe dynamic patched instead ?)
* r26 is the hidx mask
* r25 is the index in combo page
*/
std r25,STK_REG(R25)(r1)
std r26,STK_REG(R26)(r1)
std r27,STK_REG(R27)(r1)
std r28,STK_REG(R28)(r1)
std r29,STK_REG(R29)(r1)
std r30,STK_REG(R30)(r1)
std r31,STK_REG(R31)(r1)
/* Step 1:
*
* Check permissions, atomically mark the linux PTE busy
* and hashed.
*/
1:
ldarx r31,0,r6
/* Check access rights (access & ~(pte_val(*ptep))) */
andc. r0,r4,r31
bne- htab_wrong_access
/* Check if PTE is busy */
andi. r0,r31,_PAGE_BUSY
/* If so, just bail out and refault if needed. Someone else
* is changing this PTE anyway and might hash it.
*/
bne- htab_bail_ok
/* Prepare new PTE value (turn access RW into DIRTY, then
* add BUSY and ACCESSED)
*/
rlwinm r30,r4,32-9+7,31-7,31-7 /* _PAGE_RW -> _PAGE_DIRTY */
or r30,r30,r31
ori r30,r30,_PAGE_BUSY | _PAGE_ACCESSED
oris r30,r30,_PAGE_COMBO@h
/* Write the linux PTE atomically (setting busy) */
stdcx. r30,0,r6
bne- 1b
isync
/* Step 2:
*
* Insert/Update the HPTE in the hash table. At this point,
* r4 (access) is re-useable, we use it for the new HPTE flags
*/
/* Load the hidx index */
rldicl r25,r3,64-12,60
BEGIN_FTR_SECTION
cmpdi r9,0 /* check segment size */
bne 3f
END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT)
/* Calc vpn and put it in r29 */
sldi r29,r5,SID_SHIFT - VPN_SHIFT
/*
* clrldi r3,r3,64 - SID_SHIFT --> ea & 0xfffffff
* srdi r28,r3,VPN_SHIFT
*/
rldicl r28,r3,64 - VPN_SHIFT,64 - (SID_SHIFT - VPN_SHIFT)
or r29,r28,r29
/*
* Calculate hash value for primary slot and store it in r28
* r3 = va, r5 = vsid
* r0 = (va >> 12) & ((1ul << (28 - 12)) -1)
*/
rldicl r0,r3,64-12,48
xor r28,r5,r0 /* hash */
b 4f
3: /* Calc vpn and put it in r29 */
sldi r29,r5,SID_SHIFT_1T - VPN_SHIFT
/*
* clrldi r3,r3,64 - SID_SHIFT_1T --> ea & 0xffffffffff
* srdi r28,r3,VPN_SHIFT
*/
rldicl r28,r3,64 - VPN_SHIFT,64 - (SID_SHIFT_1T - VPN_SHIFT)
or r29,r28,r29
/*
* Calculate hash value for primary slot and
* store it in r28 for 1T segment
* r3 = va, r5 = vsid
*/
sldi r28,r5,25 /* vsid << 25 */
/* r0 = (va >> 12) & ((1ul << (40 - 12)) -1) */
rldicl r0,r3,64-12,36
xor r28,r28,r5 /* vsid ^ ( vsid << 25) */
xor r28,r28,r0 /* hash */
/* Convert linux PTE bits into HW equivalents */
4:
#ifdef CONFIG_PPC_SUBPAGE_PROT
andc r10,r30,r10
andi. r3,r10,0x1fe /* Get basic set of flags */
rlwinm r0,r10,32-9+1,30,30 /* _PAGE_RW -> _PAGE_USER (r0) */
#else
andi. r3,r30,0x1fe /* Get basic set of flags */
rlwinm r0,r30,32-9+1,30,30 /* _PAGE_RW -> _PAGE_USER (r0) */
#endif
xori r3,r3,HPTE_R_N /* _PAGE_EXEC -> NOEXEC */
rlwinm r4,r30,32-7+1,30,30 /* _PAGE_DIRTY -> _PAGE_USER (r4) */
and r0,r0,r4 /* _PAGE_RW & _PAGE_DIRTY ->r0 bit 30*/
andc r0,r3,r0 /* r0 = pte & ~r0 */
rlwimi r3,r0,32-1,31,31 /* Insert result into PP lsb */
/*
* Always add "C" bit for perf. Memory coherence is always enabled
*/
ori r3,r3,HPTE_R_C | HPTE_R_M
/* We eventually do the icache sync here (maybe inline that
* code rather than call a C function...)
*/
BEGIN_FTR_SECTION
mr r4,r30
mr r5,r7
bl hash_page_do_lazy_icache
END_FTR_SECTION(CPU_FTR_NOEXECUTE|CPU_FTR_COHERENT_ICACHE, CPU_FTR_NOEXECUTE)
/* At this point, r3 contains new PP bits, save them in
* place of "access" in the param area (sic)
*/
std r3,STK_PARAM(R4)(r1)
/* Get htab_hash_mask */
ld r4,htab_hash_mask@got(2)
ld r27,0(r4) /* htab_hash_mask -> r27 */
/* Check if we may already be in the hashtable, in this case, we
* go to out-of-line code to try to modify the HPTE. We look for
* the bit at (1 >> (index + 32))
*/
rldicl. r0,r31,64-12,48
li r26,0 /* Default hidx */
beq htab_insert_pte
/*
* Check if the pte was already inserted into the hash table
* as a 64k HW page, and invalidate the 64k HPTE if so.
*/
andis. r0,r31,_PAGE_COMBO@h
beq htab_inval_old_hpte
ld r6,STK_PARAM(R6)(r1)
ori r26,r6,PTE_PAGE_HIDX_OFFSET /* Load the hidx mask. */
ld r26,0(r26)
addi r5,r25,36 /* Check actual HPTE_SUB bit, this */
rldcr. r0,r31,r5,0 /* must match pgtable.h definition */
bne htab_modify_pte
htab_insert_pte:
/* real page number in r5, PTE RPN value + index */
andis. r0,r31,_PAGE_4K_PFN@h
srdi r5,r31,PTE_RPN_SHIFT
bne- htab_special_pfn
sldi r5,r5,PAGE_SHIFT-HW_PAGE_SHIFT
add r5,r5,r25
htab_special_pfn:
sldi r5,r5,HW_PAGE_SHIFT
/* Calculate primary group hash */
and r0,r28,r27
rldicr r3,r0,3,63-3 /* r0 = (hash & mask) << 3 */
/* Call ppc_md.hpte_insert */
ld r6,STK_PARAM(R4)(r1) /* Retrieve new pp bits */
mr r4,r29 /* Retrieve vpn */
li r7,0 /* !bolted, !secondary */
li r8,MMU_PAGE_4K /* page size */
li r9,MMU_PAGE_4K /* actual page size */
ld r10,STK_PARAM(R9)(r1) /* segment size */
.globl htab_call_hpte_insert1
htab_call_hpte_insert1:
bl . /* patched by htab_finish_init() */
cmpdi 0,r3,0
bge htab_pte_insert_ok /* Insertion successful */
cmpdi 0,r3,-2 /* Critical failure */
beq- htab_pte_insert_failure
/* Now try secondary slot */
/* real page number in r5, PTE RPN value + index */
andis. r0,r31,_PAGE_4K_PFN@h
srdi r5,r31,PTE_RPN_SHIFT
bne- 3f
sldi r5,r5,PAGE_SHIFT-HW_PAGE_SHIFT
add r5,r5,r25
3: sldi r5,r5,HW_PAGE_SHIFT
/* Calculate secondary group hash */
andc r0,r27,r28
rldicr r3,r0,3,63-3 /* r0 = (~hash & mask) << 3 */
/* Call ppc_md.hpte_insert */
ld r6,STK_PARAM(R4)(r1) /* Retrieve new pp bits */
mr r4,r29 /* Retrieve vpn */
li r7,HPTE_V_SECONDARY /* !bolted, secondary */
li r8,MMU_PAGE_4K /* page size */
li r9,MMU_PAGE_4K /* actual page size */
ld r10,STK_PARAM(R9)(r1) /* segment size */
.globl htab_call_hpte_insert2
htab_call_hpte_insert2:
bl . /* patched by htab_finish_init() */
cmpdi 0,r3,0
bge+ htab_pte_insert_ok /* Insertion successful */
cmpdi 0,r3,-2 /* Critical failure */
beq- htab_pte_insert_failure
/* Both are full, we need to evict something */
mftb r0
/* Pick a random group based on TB */
andi. r0,r0,1
mr r5,r28
bne 2f
not r5,r5
2: and r0,r5,r27
rldicr r3,r0,3,63-3 /* r0 = (hash & mask) << 3 */
/* Call ppc_md.hpte_remove */
.globl htab_call_hpte_remove
htab_call_hpte_remove:
bl . /* patched by htab_finish_init() */
/* Try all again */
b htab_insert_pte
/*
* Call out to C code to invalidate an 64k HW HPTE that is
* useless now that the segment has been switched to 4k pages.
*/
htab_inval_old_hpte:
mr r3,r29 /* vpn */
mr r4,r31 /* PTE.pte */
li r5,0 /* PTE.hidx */
li r6,MMU_PAGE_64K /* psize */
ld r7,STK_PARAM(R9)(r1) /* ssize */
ld r8,STK_PARAM(R8)(r1) /* local */
bl flush_hash_page
/* Clear out _PAGE_HPTE_SUB bits in the new linux PTE */
lis r0,_PAGE_HPTE_SUB@h
ori r0,r0,_PAGE_HPTE_SUB@l
andc r30,r30,r0
b htab_insert_pte
htab_bail_ok:
li r3,0
b htab_bail
htab_pte_insert_ok:
/* Insert slot number & secondary bit in PTE second half,
* clear _PAGE_BUSY and set approriate HPTE slot bit
*/
ld r6,STK_PARAM(R6)(r1)
li r0,_PAGE_BUSY
andc r30,r30,r0
/* HPTE SUB bit */
li r0,1
subfic r5,r25,27 /* Must match bit position in */
sld r0,r0,r5 /* pgtable.h */
or r30,r30,r0
/* hindx */
sldi r5,r25,2
sld r3,r3,r5
li r4,0xf
sld r4,r4,r5
andc r26,r26,r4
or r26,r26,r3
ori r5,r6,PTE_PAGE_HIDX_OFFSET
std r26,0(r5)
lwsync
std r30,0(r6)
li r3, 0
htab_bail:
ld r25,STK_REG(R25)(r1)
ld r26,STK_REG(R26)(r1)
ld r27,STK_REG(R27)(r1)
ld r28,STK_REG(R28)(r1)
ld r29,STK_REG(R29)(r1)
ld r30,STK_REG(R30)(r1)
ld r31,STK_REG(R31)(r1)
addi r1,r1,STACKFRAMESIZE
ld r0,16(r1)
mtlr r0
blr
htab_modify_pte:
/* Keep PP bits in r4 and slot idx from the PTE around in r3 */
mr r4,r3
sldi r5,r25,2
srd r3,r26,r5
/* Secondary group ? if yes, get a inverted hash value */
mr r5,r28
andi. r0,r3,0x8 /* page secondary ? */
beq 1f
not r5,r5
1: andi. r3,r3,0x7 /* extract idx alone */
/* Calculate proper slot value for ppc_md.hpte_updatepp */
and r0,r5,r27
rldicr r0,r0,3,63-3 /* r0 = (hash & mask) << 3 */
add r3,r0,r3 /* add slot idx */
/* Call ppc_md.hpte_updatepp */
mr r5,r29 /* vpn */
li r6,MMU_PAGE_4K /* base page size */
li r7,MMU_PAGE_4K /* actual page size */
ld r8,STK_PARAM(R9)(r1) /* segment size */
ld r9,STK_PARAM(R8)(r1) /* get "local" param */
.globl htab_call_hpte_updatepp
htab_call_hpte_updatepp:
bl . /* patched by htab_finish_init() */
/* if we failed because typically the HPTE wasn't really here
* we try an insertion.
*/
cmpdi 0,r3,-1
beq- htab_insert_pte
/* Clear the BUSY bit and Write out the PTE */
li r0,_PAGE_BUSY
andc r30,r30,r0
ld r6,STK_PARAM(R6)(r1)
std r30,0(r6)
li r3,0
b htab_bail
htab_wrong_access:
/* Bail out clearing reservation */
stdcx. r31,0,r6
li r3,1
b htab_bail
htab_pte_insert_failure:
/* Bail out restoring old PTE */
ld r6,STK_PARAM(R6)(r1)
std r31,0(r6)
li r3,-1
b htab_bail
#endif /* CONFIG_PPC_64K_PAGES */
#ifdef CONFIG_PPC_HAS_HASH_64K
/*****************************************************************************
* *
* 64K SW & 64K HW in a 64K segment pages implementation *
* *
*****************************************************************************/
_GLOBAL(__hash_page_64K)
mflr r0
std r0,16(r1)
stdu r1,-STACKFRAMESIZE(r1)
/* Save all params that we need after a function call */
std r6,STK_PARAM(R6)(r1)
std r8,STK_PARAM(R8)(r1)
std r9,STK_PARAM(R9)(r1)
/* Save non-volatile registers.
* r31 will hold "old PTE"
* r30 is "new PTE"
* r29 is vpn
* r28 is a hash value
* r27 is hashtab mask (maybe dynamic patched instead ?)
*/
std r27,STK_REG(R27)(r1)
std r28,STK_REG(R28)(r1)
std r29,STK_REG(R29)(r1)
std r30,STK_REG(R30)(r1)
std r31,STK_REG(R31)(r1)
/* Step 1:
*
* Check permissions, atomically mark the linux PTE busy
* and hashed.
*/
1:
ldarx r31,0,r6
/* Check access rights (access & ~(pte_val(*ptep))) */
andc. r0,r4,r31
bne- ht64_wrong_access
/* Check if PTE is busy */
andi. r0,r31,_PAGE_BUSY
/* If so, just bail out and refault if needed. Someone else
* is changing this PTE anyway and might hash it.
*/
bne- ht64_bail_ok
BEGIN_FTR_SECTION
/* Check if PTE has the cache-inhibit bit set */
andi. r0,r31,_PAGE_NO_CACHE
/* If so, bail out and refault as a 4k page */
bne- ht64_bail_ok
END_MMU_FTR_SECTION_IFCLR(MMU_FTR_CI_LARGE_PAGE)
/* Prepare new PTE value (turn access RW into DIRTY, then
* add BUSY and ACCESSED)
*/
rlwinm r30,r4,32-9+7,31-7,31-7 /* _PAGE_RW -> _PAGE_DIRTY */
or r30,r30,r31
ori r30,r30,_PAGE_BUSY | _PAGE_ACCESSED
/* Write the linux PTE atomically (setting busy) */
stdcx. r30,0,r6
bne- 1b
isync
/* Step 2:
*
* Insert/Update the HPTE in the hash table. At this point,
* r4 (access) is re-useable, we use it for the new HPTE flags
*/
BEGIN_FTR_SECTION
cmpdi r9,0 /* check segment size */
bne 3f
END_MMU_FTR_SECTION_IFSET(MMU_FTR_1T_SEGMENT)
/* Calc vpn and put it in r29 */
sldi r29,r5,SID_SHIFT - VPN_SHIFT
rldicl r28,r3,64 - VPN_SHIFT,64 - (SID_SHIFT - VPN_SHIFT)
or r29,r28,r29
/* Calculate hash value for primary slot and store it in r28
* r3 = va, r5 = vsid
* r0 = (va >> 16) & ((1ul << (28 - 16)) -1)
*/
rldicl r0,r3,64-16,52
xor r28,r5,r0 /* hash */
b 4f
3: /* Calc vpn and put it in r29 */
sldi r29,r5,SID_SHIFT_1T - VPN_SHIFT
rldicl r28,r3,64 - VPN_SHIFT,64 - (SID_SHIFT_1T - VPN_SHIFT)
or r29,r28,r29
/*
* calculate hash value for primary slot and
* store it in r28 for 1T segment
* r3 = va, r5 = vsid
*/
sldi r28,r5,25 /* vsid << 25 */
/* r0 = (va >> 16) & ((1ul << (40 - 16)) -1) */
rldicl r0,r3,64-16,40
xor r28,r28,r5 /* vsid ^ ( vsid << 25) */
xor r28,r28,r0 /* hash */
/* Convert linux PTE bits into HW equivalents */
4: andi. r3,r30,0x1fe /* Get basic set of flags */
xori r3,r3,HPTE_R_N /* _PAGE_EXEC -> NOEXEC */
rlwinm r0,r30,32-9+1,30,30 /* _PAGE_RW -> _PAGE_USER (r0) */
rlwinm r4,r30,32-7+1,30,30 /* _PAGE_DIRTY -> _PAGE_USER (r4) */
and r0,r0,r4 /* _PAGE_RW & _PAGE_DIRTY ->r0 bit 30*/
andc r0,r30,r0 /* r0 = pte & ~r0 */
rlwimi r3,r0,32-1,31,31 /* Insert result into PP lsb */
/*
* Always add "C" bit for perf. Memory coherence is always enabled
*/
ori r3,r3,HPTE_R_C | HPTE_R_M
/* We eventually do the icache sync here (maybe inline that
* code rather than call a C function...)
*/
BEGIN_FTR_SECTION
mr r4,r30
mr r5,r7
bl hash_page_do_lazy_icache
END_FTR_SECTION(CPU_FTR_NOEXECUTE|CPU_FTR_COHERENT_ICACHE, CPU_FTR_NOEXECUTE)
/* At this point, r3 contains new PP bits, save them in
* place of "access" in the param area (sic)
*/
std r3,STK_PARAM(R4)(r1)
/* Get htab_hash_mask */
ld r4,htab_hash_mask@got(2)
ld r27,0(r4) /* htab_hash_mask -> r27 */
/* Check if we may already be in the hashtable, in this case, we
* go to out-of-line code to try to modify the HPTE
*/
rldicl. r0,r31,64-12,48
bne ht64_modify_pte
ht64_insert_pte:
/* Clear hpte bits in new pte (we also clear BUSY btw) and
* add _PAGE_HPTE_SUB0
*/
lis r0,_PAGE_HPTEFLAGS@h
ori r0,r0,_PAGE_HPTEFLAGS@l
andc r30,r30,r0
#ifdef CONFIG_PPC_64K_PAGES
oris r30,r30,_PAGE_HPTE_SUB0@h
#else
ori r30,r30,_PAGE_HASHPTE
#endif
/* Phyical address in r5 */
rldicl r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
sldi r5,r5,PAGE_SHIFT
/* Calculate primary group hash */
and r0,r28,r27
rldicr r3,r0,3,63-3 /* r0 = (hash & mask) << 3 */
/* Call ppc_md.hpte_insert */
ld r6,STK_PARAM(R4)(r1) /* Retrieve new pp bits */
mr r4,r29 /* Retrieve vpn */
li r7,0 /* !bolted, !secondary */
li r8,MMU_PAGE_64K
li r9,MMU_PAGE_64K /* actual page size */
ld r10,STK_PARAM(R9)(r1) /* segment size */
.globl ht64_call_hpte_insert1
ht64_call_hpte_insert1:
bl . /* patched by htab_finish_init() */
cmpdi 0,r3,0
bge ht64_pte_insert_ok /* Insertion successful */
cmpdi 0,r3,-2 /* Critical failure */
beq- ht64_pte_insert_failure
/* Now try secondary slot */
/* Phyical address in r5 */
rldicl r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
sldi r5,r5,PAGE_SHIFT
/* Calculate secondary group hash */
andc r0,r27,r28
rldicr r3,r0,3,63-3 /* r0 = (~hash & mask) << 3 */
/* Call ppc_md.hpte_insert */
ld r6,STK_PARAM(R4)(r1) /* Retrieve new pp bits */
mr r4,r29 /* Retrieve vpn */
li r7,HPTE_V_SECONDARY /* !bolted, secondary */
li r8,MMU_PAGE_64K
li r9,MMU_PAGE_64K /* actual page size */
ld r10,STK_PARAM(R9)(r1) /* segment size */
.globl ht64_call_hpte_insert2
ht64_call_hpte_insert2:
bl . /* patched by htab_finish_init() */
cmpdi 0,r3,0
bge+ ht64_pte_insert_ok /* Insertion successful */
cmpdi 0,r3,-2 /* Critical failure */
beq- ht64_pte_insert_failure
/* Both are full, we need to evict something */
mftb r0
/* Pick a random group based on TB */
andi. r0,r0,1
mr r5,r28
bne 2f
not r5,r5
2: and r0,r5,r27
rldicr r3,r0,3,63-3 /* r0 = (hash & mask) << 3 */
/* Call ppc_md.hpte_remove */
.globl ht64_call_hpte_remove
ht64_call_hpte_remove:
bl . /* patched by htab_finish_init() */
/* Try all again */
b ht64_insert_pte
ht64_bail_ok:
li r3,0
b ht64_bail
ht64_pte_insert_ok:
/* Insert slot number & secondary bit in PTE */
rldimi r30,r3,12,63-15
/* Write out the PTE with a normal write
* (maybe add eieio may be good still ?)
*/
ht64_write_out_pte:
ld r6,STK_PARAM(R6)(r1)
std r30,0(r6)
li r3, 0
ht64_bail:
ld r27,STK_REG(R27)(r1)
ld r28,STK_REG(R28)(r1)
ld r29,STK_REG(R29)(r1)
ld r30,STK_REG(R30)(r1)
ld r31,STK_REG(R31)(r1)
addi r1,r1,STACKFRAMESIZE
ld r0,16(r1)
mtlr r0
blr
ht64_modify_pte:
/* Keep PP bits in r4 and slot idx from the PTE around in r3 */
mr r4,r3
rlwinm r3,r31,32-12,29,31
/* Secondary group ? if yes, get a inverted hash value */
mr r5,r28
andi. r0,r31,_PAGE_F_SECOND
beq 1f
not r5,r5
1:
/* Calculate proper slot value for ppc_md.hpte_updatepp */
and r0,r5,r27
rldicr r0,r0,3,63-3 /* r0 = (hash & mask) << 3 */
add r3,r0,r3 /* add slot idx */
/* Call ppc_md.hpte_updatepp */
mr r5,r29 /* vpn */
li r6,MMU_PAGE_64K /* base page size */
li r7,MMU_PAGE_64K /* actual page size */
ld r8,STK_PARAM(R9)(r1) /* segment size */
ld r9,STK_PARAM(R8)(r1) /* get "local" param */
.globl ht64_call_hpte_updatepp
ht64_call_hpte_updatepp:
bl . /* patched by htab_finish_init() */
/* if we failed because typically the HPTE wasn't really here
* we try an insertion.
*/
cmpdi 0,r3,-1
beq- ht64_insert_pte
/* Clear the BUSY bit and Write out the PTE */
li r0,_PAGE_BUSY
andc r30,r30,r0
b ht64_write_out_pte
ht64_wrong_access:
/* Bail out clearing reservation */
stdcx. r31,0,r6
li r3,1
b ht64_bail
ht64_pte_insert_failure:
/* Bail out restoring old PTE */
ld r6,STK_PARAM(R6)(r1)
std r31,0(r6)
li r3,-1
b ht64_bail
#endif /* CONFIG_PPC_HAS_HASH_64K */
/*****************************************************************************
* *
* Huge pages implementation is in hugetlbpage.c *
* *
*****************************************************************************/
