diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/mm/copypage-v4wb.S | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/arm/mm/copypage-v4wb.S')
-rw-r--r-- | arch/arm/mm/copypage-v4wb.S | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/arch/arm/mm/copypage-v4wb.S b/arch/arm/mm/copypage-v4wb.S new file mode 100644 index 0000000..b94c345 --- /dev/null +++ b/arch/arm/mm/copypage-v4wb.S @@ -0,0 +1,79 @@ +/* + * linux/arch/arm/lib/copypage.S + * + * Copyright (C) 1995-1999 Russell King + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * ASM optimised string functions + */ +#include <linux/linkage.h> +#include <linux/init.h> +#include <asm/constants.h> + + .text + .align 5 +/* + * ARMv4 optimised copy_user_page + * + * We flush the destination cache lines just before we write the data into the + * corresponding address. Since the Dcache is read-allocate, this removes the + * Dcache aliasing issue. The writes will be forwarded to the write buffer, + * and merged as appropriate. + * + * Note: We rely on all ARMv4 processors implementing the "invalidate D line" + * instruction. If your processor does not supply this, you have to write your + * own copy_user_page that does the right thing. + */ +ENTRY(v4wb_copy_user_page) + stmfd sp!, {r4, lr} @ 2 + mov r2, #PAGE_SZ/64 @ 1 + ldmia r1!, {r3, r4, ip, lr} @ 4 +1: mcr p15, 0, r0, c7, c6, 1 @ 1 invalidate D line + stmia r0!, {r3, r4, ip, lr} @ 4 + ldmia r1!, {r3, r4, ip, lr} @ 4+1 + stmia r0!, {r3, r4, ip, lr} @ 4 + ldmia r1!, {r3, r4, ip, lr} @ 4 + mcr p15, 0, r0, c7, c6, 1 @ 1 invalidate D line + stmia r0!, {r3, r4, ip, lr} @ 4 + ldmia r1!, {r3, r4, ip, lr} @ 4 + subs r2, r2, #1 @ 1 + stmia r0!, {r3, r4, ip, lr} @ 4 + ldmneia r1!, {r3, r4, ip, lr} @ 4 + bne 1b @ 1 + mcr p15, 0, r1, c7, c10, 4 @ 1 drain WB + ldmfd sp!, {r4, pc} @ 3 + + .align 5 +/* + * ARMv4 optimised clear_user_page + * + * Same story as above. + */ +ENTRY(v4wb_clear_user_page) + str lr, [sp, #-4]! + mov r1, #PAGE_SZ/64 @ 1 + mov r2, #0 @ 1 + mov r3, #0 @ 1 + mov ip, #0 @ 1 + mov lr, #0 @ 1 +1: mcr p15, 0, r0, c7, c6, 1 @ 1 invalidate D line + stmia r0!, {r2, r3, ip, lr} @ 4 + stmia r0!, {r2, r3, ip, lr} @ 4 + mcr p15, 0, r0, c7, c6, 1 @ 1 invalidate D line + stmia r0!, {r2, r3, ip, lr} @ 4 + stmia r0!, {r2, r3, ip, lr} @ 4 + subs r1, r1, #1 @ 1 + bne 1b @ 1 + mcr p15, 0, r1, c7, c10, 4 @ 1 drain WB + ldr pc, [sp], #4 + + __INITDATA + + .type v4wb_user_fns, #object +ENTRY(v4wb_user_fns) + .long v4wb_clear_user_page + .long v4wb_copy_user_page + .size v4wb_user_fns, . - v4wb_user_fns |