You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
291 lines
8.0 KiB
291 lines
8.0 KiB
/*
|
|
* Low-level SLB routines
|
|
*
|
|
* Copyright (C) 2004 David Gibson <dwg@au.ibm.com>, IBM
|
|
*
|
|
* Based on earlier C version:
|
|
* Dave Engebretsen and Mike Corrigan {engebret|mikejc}@us.ibm.com
|
|
* Copyright (c) 2001 Dave Engebretsen
|
|
* Copyright (C) 2002 Anton Blanchard <anton@au.ibm.com>, IBM
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#include <asm/processor.h>
|
|
#include <asm/ppc_asm.h>
|
|
#include <asm/asm-offsets.h>
|
|
#include <asm/cputable.h>
|
|
#include <asm/page.h>
|
|
#include <asm/mmu.h>
|
|
#include <asm/pgtable.h>
|
|
#include <asm/firmware.h>
|
|
|
|
/* void slb_allocate_realmode(unsigned long ea);
|
|
*
|
|
* Create an SLB entry for the given EA (user or kernel).
|
|
* r3 = faulting address, r13 = PACA
|
|
* r9, r10, r11 are clobbered by this function
|
|
* No other registers are examined or changed.
|
|
*/
|
|
_GLOBAL(slb_allocate_realmode)
|
|
/* r3 = faulting address */
|
|
|
|
srdi r9,r3,60 /* get region */
|
|
srdi r10,r3,28 /* get esid */
|
|
cmpldi cr7,r9,0xc /* cmp PAGE_OFFSET for later use */
|
|
|
|
/* r3 = address, r10 = esid, cr7 = <> PAGE_OFFSET */
|
|
blt cr7,0f /* user or kernel? */
|
|
|
|
/* kernel address: proto-VSID = ESID */
|
|
/* WARNING - MAGIC: we don't use the VSID 0xfffffffff, but
|
|
* this code will generate the protoVSID 0xfffffffff for the
|
|
* top segment. That's ok, the scramble below will translate
|
|
* it to VSID 0, which is reserved as a bad VSID - one which
|
|
* will never have any pages in it. */
|
|
|
|
/* Check if hitting the linear mapping of the vmalloc/ioremap
|
|
* kernel space
|
|
*/
|
|
bne cr7,1f
|
|
|
|
/* Linear mapping encoding bits, the "li" instruction below will
|
|
* be patched by the kernel at boot
|
|
*/
|
|
_GLOBAL(slb_miss_kernel_load_linear)
|
|
li r11,0
|
|
BEGIN_FTR_SECTION
|
|
b slb_finish_load
|
|
END_FTR_SECTION_IFCLR(CPU_FTR_1T_SEGMENT)
|
|
b slb_finish_load_1T
|
|
|
|
1: /* vmalloc/ioremap mapping encoding bits, the "li" instructions below
|
|
* will be patched by the kernel at boot
|
|
*/
|
|
BEGIN_FTR_SECTION
|
|
/* check whether this is in vmalloc or ioremap space */
|
|
clrldi r11,r10,48
|
|
cmpldi r11,(VMALLOC_SIZE >> 28) - 1
|
|
bgt 5f
|
|
lhz r11,PACAVMALLOCSLLP(r13)
|
|
b 6f
|
|
5:
|
|
END_FTR_SECTION_IFCLR(CPU_FTR_CI_LARGE_PAGE)
|
|
_GLOBAL(slb_miss_kernel_load_io)
|
|
li r11,0
|
|
6:
|
|
BEGIN_FTR_SECTION
|
|
b slb_finish_load
|
|
END_FTR_SECTION_IFCLR(CPU_FTR_1T_SEGMENT)
|
|
b slb_finish_load_1T
|
|
|
|
0: /* user address: proto-VSID = context << 15 | ESID. First check
|
|
* if the address is within the boundaries of the user region
|
|
*/
|
|
srdi. r9,r10,USER_ESID_BITS
|
|
bne- 8f /* invalid ea bits set */
|
|
|
|
|
|
/* when using slices, we extract the psize off the slice bitmaps
|
|
* and then we need to get the sllp encoding off the mmu_psize_defs
|
|
* array.
|
|
*
|
|
* XXX This is a bit inefficient especially for the normal case,
|
|
* so we should try to implement a fast path for the standard page
|
|
* size using the old sllp value so we avoid the array. We cannot
|
|
* really do dynamic patching unfortunately as processes might flip
|
|
* between 4k and 64k standard page size
|
|
*/
|
|
#ifdef CONFIG_PPC_MM_SLICES
|
|
cmpldi r10,16
|
|
|
|
/* Get the slice index * 4 in r11 and matching slice size mask in r9 */
|
|
ld r9,PACALOWSLICESPSIZE(r13)
|
|
sldi r11,r10,2
|
|
blt 5f
|
|
ld r9,PACAHIGHSLICEPSIZE(r13)
|
|
srdi r11,r10,(SLICE_HIGH_SHIFT - SLICE_LOW_SHIFT - 2)
|
|
andi. r11,r11,0x3c
|
|
|
|
5: /* Extract the psize and multiply to get an array offset */
|
|
srd r9,r9,r11
|
|
andi. r9,r9,0xf
|
|
mulli r9,r9,MMUPSIZEDEFSIZE
|
|
|
|
/* Now get to the array and obtain the sllp
|
|
*/
|
|
ld r11,PACATOC(r13)
|
|
ld r11,mmu_psize_defs@got(r11)
|
|
add r11,r11,r9
|
|
ld r11,MMUPSIZESLLP(r11)
|
|
ori r11,r11,SLB_VSID_USER
|
|
#else
|
|
/* paca context sllp already contains the SLB_VSID_USER bits */
|
|
lhz r11,PACACONTEXTSLLP(r13)
|
|
#endif /* CONFIG_PPC_MM_SLICES */
|
|
|
|
ld r9,PACACONTEXTID(r13)
|
|
BEGIN_FTR_SECTION
|
|
cmpldi r10,0x1000
|
|
END_FTR_SECTION_IFSET(CPU_FTR_1T_SEGMENT)
|
|
rldimi r10,r9,USER_ESID_BITS,0
|
|
BEGIN_FTR_SECTION
|
|
bge slb_finish_load_1T
|
|
END_FTR_SECTION_IFSET(CPU_FTR_1T_SEGMENT)
|
|
b slb_finish_load
|
|
|
|
8: /* invalid EA */
|
|
li r10,0 /* BAD_VSID */
|
|
li r11,SLB_VSID_USER /* flags don't much matter */
|
|
b slb_finish_load
|
|
|
|
#ifdef __DISABLED__
|
|
|
|
/* void slb_allocate_user(unsigned long ea);
|
|
*
|
|
* Create an SLB entry for the given EA (user or kernel).
|
|
* r3 = faulting address, r13 = PACA
|
|
* r9, r10, r11 are clobbered by this function
|
|
* No other registers are examined or changed.
|
|
*
|
|
* It is called with translation enabled in order to be able to walk the
|
|
* page tables. This is not currently used.
|
|
*/
|
|
_GLOBAL(slb_allocate_user)
|
|
/* r3 = faulting address */
|
|
srdi r10,r3,28 /* get esid */
|
|
|
|
crset 4*cr7+lt /* set "user" flag for later */
|
|
|
|
/* check if we fit in the range covered by the pagetables*/
|
|
srdi. r9,r3,PGTABLE_EADDR_SIZE
|
|
crnot 4*cr0+eq,4*cr0+eq
|
|
beqlr
|
|
|
|
/* now we need to get to the page tables in order to get the page
|
|
* size encoding from the PMD. In the future, we'll be able to deal
|
|
* with 1T segments too by getting the encoding from the PGD instead
|
|
*/
|
|
ld r9,PACAPGDIR(r13)
|
|
cmpldi cr0,r9,0
|
|
beqlr
|
|
rlwinm r11,r10,8,25,28
|
|
ldx r9,r9,r11 /* get pgd_t */
|
|
cmpldi cr0,r9,0
|
|
beqlr
|
|
rlwinm r11,r10,3,17,28
|
|
ldx r9,r9,r11 /* get pmd_t */
|
|
cmpldi cr0,r9,0
|
|
beqlr
|
|
|
|
/* build vsid flags */
|
|
andi. r11,r9,SLB_VSID_LLP
|
|
ori r11,r11,SLB_VSID_USER
|
|
|
|
/* get context to calculate proto-VSID */
|
|
ld r9,PACACONTEXTID(r13)
|
|
rldimi r10,r9,USER_ESID_BITS,0
|
|
|
|
/* fall through slb_finish_load */
|
|
|
|
#endif /* __DISABLED__ */
|
|
|
|
|
|
/*
|
|
* Finish loading of an SLB entry and return
|
|
*
|
|
* r3 = EA, r10 = proto-VSID, r11 = flags, clobbers r9, cr7 = <> PAGE_OFFSET
|
|
*/
|
|
slb_finish_load:
|
|
ASM_VSID_SCRAMBLE(r10,r9,256M)
|
|
rldimi r11,r10,SLB_VSID_SHIFT,16 /* combine VSID and flags */
|
|
|
|
/* r3 = EA, r11 = VSID data */
|
|
/*
|
|
* Find a slot, round robin. Previously we tried to find a
|
|
* free slot first but that took too long. Unfortunately we
|
|
* dont have any LRU information to help us choose a slot.
|
|
*/
|
|
#ifdef CONFIG_PPC_ISERIES
|
|
BEGIN_FW_FTR_SECTION
|
|
/*
|
|
* On iSeries, the "bolted" stack segment can be cast out on
|
|
* shared processor switch so we need to check for a miss on
|
|
* it and restore it to the right slot.
|
|
*/
|
|
ld r9,PACAKSAVE(r13)
|
|
clrrdi r9,r9,28
|
|
clrrdi r3,r3,28
|
|
li r10,SLB_NUM_BOLTED-1 /* Stack goes in last bolted slot */
|
|
cmpld r9,r3
|
|
beq 3f
|
|
END_FW_FTR_SECTION_IFSET(FW_FEATURE_ISERIES)
|
|
#endif /* CONFIG_PPC_ISERIES */
|
|
|
|
7: ld r10,PACASTABRR(r13)
|
|
addi r10,r10,1
|
|
/* This gets soft patched on boot. */
|
|
_GLOBAL(slb_compare_rr_to_size)
|
|
cmpldi r10,0
|
|
|
|
blt+ 4f
|
|
li r10,SLB_NUM_BOLTED
|
|
|
|
4:
|
|
std r10,PACASTABRR(r13)
|
|
|
|
3:
|
|
rldimi r3,r10,0,36 /* r3= EA[0:35] | entry */
|
|
oris r10,r3,SLB_ESID_V@h /* r3 |= SLB_ESID_V */
|
|
|
|
/* r3 = ESID data, r11 = VSID data */
|
|
|
|
/*
|
|
* No need for an isync before or after this slbmte. The exception
|
|
* we enter with and the rfid we exit with are context synchronizing.
|
|
*/
|
|
slbmte r11,r10
|
|
|
|
/* we're done for kernel addresses */
|
|
crclr 4*cr0+eq /* set result to "success" */
|
|
bgelr cr7
|
|
|
|
/* Update the slb cache */
|
|
lhz r3,PACASLBCACHEPTR(r13) /* offset = paca->slb_cache_ptr */
|
|
cmpldi r3,SLB_CACHE_ENTRIES
|
|
bge 1f
|
|
|
|
/* still room in the slb cache */
|
|
sldi r11,r3,1 /* r11 = offset * sizeof(u16) */
|
|
rldicl r10,r10,36,28 /* get low 16 bits of the ESID */
|
|
add r11,r11,r13 /* r11 = (u16 *)paca + offset */
|
|
sth r10,PACASLBCACHE(r11) /* paca->slb_cache[offset] = esid */
|
|
addi r3,r3,1 /* offset++ */
|
|
b 2f
|
|
1: /* offset >= SLB_CACHE_ENTRIES */
|
|
li r3,SLB_CACHE_ENTRIES+1
|
|
2:
|
|
sth r3,PACASLBCACHEPTR(r13) /* paca->slb_cache_ptr = offset */
|
|
crclr 4*cr0+eq /* set result to "success" */
|
|
blr
|
|
|
|
/*
|
|
* Finish loading of a 1T SLB entry (for the kernel linear mapping) and return.
|
|
* We assume legacy iSeries will never have 1T segments.
|
|
*
|
|
* r3 = EA, r10 = proto-VSID, r11 = flags, clobbers r9
|
|
*/
|
|
slb_finish_load_1T:
|
|
srdi r10,r10,40-28 /* get 1T ESID */
|
|
ASM_VSID_SCRAMBLE(r10,r9,1T)
|
|
rldimi r11,r10,SLB_VSID_SHIFT_1T,16 /* combine VSID and flags */
|
|
li r10,MMU_SEGSIZE_1T
|
|
rldimi r11,r10,SLB_VSID_SSIZE_SHIFT,0 /* insert segment size */
|
|
|
|
/* r3 = EA, r11 = VSID data */
|
|
clrrdi r3,r3,SID_SHIFT_1T /* clear out non-ESID bits */
|
|
b 7b
|
|
|
|
|