linux/arch/sparc/lib/copy_page.S
David S. Miller b2d4383480 sparc64: Make PAGE_OFFSET variable.
Choose PAGE_OFFSET dynamically based upon cpu type.

Original UltraSPARC-I (spitfire) chips only supported a 44-bit
virtual address space.

Newer chips (T4 and later) support 52-bit virtual addresses
and up to 47-bits of physical memory space.

Therefore we have to adjust PAGE_SIZE dynamically based upon
the capabilities of the chip.

Note that this change alone does not allow us to support > 43-bit
physical memory, to do that we need to re-arrange our page table
support.  The current encodings of the pmd_t and pgd_t pointers
restricts us to "32 + 11" == 43 bits.

This change can waste quite a bit of memory for the various tables.
In particular, a future change should work to size and allocate
kern_linear_bitmap[] and sparc64_valid_addr_bitmap[] dynamically.
This isn't easy as we really cannot take a TLB miss when accessing
kern_linear_bitmap[].  We'd have to lock it into the TLB or similar.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Bob Picco <bob.picco@oracle.com>
2013-11-12 15:22:34 -08:00

251 lines
5.8 KiB
ArmAsm

/* clear_page.S: UltraSparc optimized copy page.
*
* Copyright (C) 1996, 1998, 1999, 2000, 2004 David S. Miller (davem@redhat.com)
* Copyright (C) 1997 Jakub Jelinek (jakub@redhat.com)
*/
#include <asm/visasm.h>
#include <asm/thread_info.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/spitfire.h>
#include <asm/head.h>
/* What we used to do was lock a TLB entry into a specific
* TLB slot, clear the page with interrupts disabled, then
* restore the original TLB entry. This was great for
* disturbing the TLB as little as possible, but it meant
* we had to keep interrupts disabled for a long time.
*
* Now, we simply use the normal TLB loading mechanism,
* and this makes the cpu choose a slot all by itself.
* Then we do a normal TLB flush on exit. We need only
* disable preemption during the clear.
*/
#define DCACHE_SIZE (PAGE_SIZE * 2)
#if (PAGE_SHIFT == 13)
#define PAGE_SIZE_REM 0x80
#elif (PAGE_SHIFT == 16)
#define PAGE_SIZE_REM 0x100
#else
#error Wrong PAGE_SHIFT specified
#endif
#define TOUCH(reg0, reg1, reg2, reg3, reg4, reg5, reg6, reg7) \
fsrc2 %reg0, %f48; fsrc2 %reg1, %f50; \
fsrc2 %reg2, %f52; fsrc2 %reg3, %f54; \
fsrc2 %reg4, %f56; fsrc2 %reg5, %f58; \
fsrc2 %reg6, %f60; fsrc2 %reg7, %f62;
.text
.align 32
.globl copy_user_page
.type copy_user_page,#function
copy_user_page: /* %o0=dest, %o1=src, %o2=vaddr */
lduw [%g6 + TI_PRE_COUNT], %o4
sethi %hi(PAGE_OFFSET), %g2
sethi %hi(PAGE_SIZE), %o3
ldx [%g2 + %lo(PAGE_OFFSET)], %g2
sethi %hi(PAGE_KERNEL_LOCKED), %g3
ldx [%g3 + %lo(PAGE_KERNEL_LOCKED)], %g3
sub %o0, %g2, %g1 ! dest paddr
sub %o1, %g2, %g2 ! src paddr
and %o2, %o3, %o0 ! vaddr D-cache alias bit
or %g1, %g3, %g1 ! dest TTE data
or %g2, %g3, %g2 ! src TTE data
sethi %hi(TLBTEMP_BASE), %o3
sethi %hi(DCACHE_SIZE), %o1
add %o0, %o3, %o0 ! dest TTE vaddr
add %o4, 1, %o2
add %o0, %o1, %o1 ! src TTE vaddr
/* Disable preemption. */
mov TLB_TAG_ACCESS, %g3
stw %o2, [%g6 + TI_PRE_COUNT]
/* Load TLB entries. */
rdpr %pstate, %o2
wrpr %o2, PSTATE_IE, %pstate
stxa %o0, [%g3] ASI_DMMU
stxa %g1, [%g0] ASI_DTLB_DATA_IN
membar #Sync
stxa %o1, [%g3] ASI_DMMU
stxa %g2, [%g0] ASI_DTLB_DATA_IN
membar #Sync
wrpr %o2, 0x0, %pstate
cheetah_copy_page_insn:
ba,pt %xcc, 9f
nop
1:
VISEntryHalf
membar #StoreLoad | #StoreStore | #LoadStore
sethi %hi((PAGE_SIZE/64)-2), %o2
mov %o0, %g1
prefetch [%o1 + 0x000], #one_read
or %o2, %lo((PAGE_SIZE/64)-2), %o2
prefetch [%o1 + 0x040], #one_read
prefetch [%o1 + 0x080], #one_read
prefetch [%o1 + 0x0c0], #one_read
ldd [%o1 + 0x000], %f0
prefetch [%o1 + 0x100], #one_read
ldd [%o1 + 0x008], %f2
prefetch [%o1 + 0x140], #one_read
ldd [%o1 + 0x010], %f4
prefetch [%o1 + 0x180], #one_read
fsrc2 %f0, %f16
ldd [%o1 + 0x018], %f6
fsrc2 %f2, %f18
ldd [%o1 + 0x020], %f8
fsrc2 %f4, %f20
ldd [%o1 + 0x028], %f10
fsrc2 %f6, %f22
ldd [%o1 + 0x030], %f12
fsrc2 %f8, %f24
ldd [%o1 + 0x038], %f14
fsrc2 %f10, %f26
ldd [%o1 + 0x040], %f0
1: ldd [%o1 + 0x048], %f2
fsrc2 %f12, %f28
ldd [%o1 + 0x050], %f4
fsrc2 %f14, %f30
stda %f16, [%o0] ASI_BLK_P
ldd [%o1 + 0x058], %f6
fsrc2 %f0, %f16
ldd [%o1 + 0x060], %f8
fsrc2 %f2, %f18
ldd [%o1 + 0x068], %f10
fsrc2 %f4, %f20
ldd [%o1 + 0x070], %f12
fsrc2 %f6, %f22
ldd [%o1 + 0x078], %f14
fsrc2 %f8, %f24
ldd [%o1 + 0x080], %f0
prefetch [%o1 + 0x180], #one_read
fsrc2 %f10, %f26
subcc %o2, 1, %o2
add %o0, 0x40, %o0
bne,pt %xcc, 1b
add %o1, 0x40, %o1
ldd [%o1 + 0x048], %f2
fsrc2 %f12, %f28
ldd [%o1 + 0x050], %f4
fsrc2 %f14, %f30
stda %f16, [%o0] ASI_BLK_P
ldd [%o1 + 0x058], %f6
fsrc2 %f0, %f16
ldd [%o1 + 0x060], %f8
fsrc2 %f2, %f18
ldd [%o1 + 0x068], %f10
fsrc2 %f4, %f20
ldd [%o1 + 0x070], %f12
fsrc2 %f6, %f22
add %o0, 0x40, %o0
ldd [%o1 + 0x078], %f14
fsrc2 %f8, %f24
fsrc2 %f10, %f26
fsrc2 %f12, %f28
fsrc2 %f14, %f30
stda %f16, [%o0] ASI_BLK_P
membar #Sync
VISExitHalf
ba,pt %xcc, 5f
nop
9:
VISEntry
ldub [%g6 + TI_FAULT_CODE], %g3
mov %o0, %g1
cmp %g3, 0
rd %asi, %g3
be,a,pt %icc, 1f
wr %g0, ASI_BLK_P, %asi
wr %g0, ASI_BLK_COMMIT_P, %asi
1: ldda [%o1] ASI_BLK_P, %f0
add %o1, 0x40, %o1
ldda [%o1] ASI_BLK_P, %f16
add %o1, 0x40, %o1
sethi %hi(PAGE_SIZE), %o2
1: TOUCH(f0, f2, f4, f6, f8, f10, f12, f14)
ldda [%o1] ASI_BLK_P, %f32
stda %f48, [%o0] %asi
add %o1, 0x40, %o1
sub %o2, 0x40, %o2
add %o0, 0x40, %o0
TOUCH(f16, f18, f20, f22, f24, f26, f28, f30)
ldda [%o1] ASI_BLK_P, %f0
stda %f48, [%o0] %asi
add %o1, 0x40, %o1
sub %o2, 0x40, %o2
add %o0, 0x40, %o0
TOUCH(f32, f34, f36, f38, f40, f42, f44, f46)
ldda [%o1] ASI_BLK_P, %f16
stda %f48, [%o0] %asi
sub %o2, 0x40, %o2
add %o1, 0x40, %o1
cmp %o2, PAGE_SIZE_REM
bne,pt %xcc, 1b
add %o0, 0x40, %o0
#if (PAGE_SHIFT == 16)
TOUCH(f0, f2, f4, f6, f8, f10, f12, f14)
ldda [%o1] ASI_BLK_P, %f32
stda %f48, [%o0] %asi
add %o1, 0x40, %o1
sub %o2, 0x40, %o2
add %o0, 0x40, %o0
TOUCH(f16, f18, f20, f22, f24, f26, f28, f30)
ldda [%o1] ASI_BLK_P, %f0
stda %f48, [%o0] %asi
add %o1, 0x40, %o1
sub %o2, 0x40, %o2
add %o0, 0x40, %o0
membar #Sync
stda %f32, [%o0] %asi
add %o0, 0x40, %o0
stda %f0, [%o0] %asi
#else
membar #Sync
stda %f0, [%o0] %asi
add %o0, 0x40, %o0
stda %f16, [%o0] %asi
#endif
membar #Sync
wr %g3, 0x0, %asi
VISExit
5:
stxa %g0, [%g1] ASI_DMMU_DEMAP
membar #Sync
sethi %hi(DCACHE_SIZE), %g2
stxa %g0, [%g1 + %g2] ASI_DMMU_DEMAP
membar #Sync
retl
stw %o4, [%g6 + TI_PRE_COUNT]
.size copy_user_page, .-copy_user_page
.globl cheetah_patch_copy_page
cheetah_patch_copy_page:
sethi %hi(0x01000000), %o1 ! NOP
sethi %hi(cheetah_copy_page_insn), %o0
or %o0, %lo(cheetah_copy_page_insn), %o0
stw %o1, [%o0]
membar #StoreStore
flush %o0
retl
nop