diff options
author | Michael Neuling <mikey@neuling.org> | 2013-05-29 19:34:29 (GMT) |
---|---|---|
committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2013-05-31 22:29:26 (GMT) |
commit | 280a5ba22ca35575721d42e536176a3561f4ec43 (patch) | |
tree | 1f3d8d44e8fe3fdcd30bd45a0b881a0d878cd7b2 /arch/powerpc/lib/copypage_power7.S | |
parent | a515348fc69fd1d9e8ebd34a16f1026d7fe32048 (diff) | |
download | linux-280a5ba22ca35575721d42e536176a3561f4ec43.tar.xz |
powerpc/pseries: Improve stream generation comments in copypage/user
No code changes, just documenting what's happening a little better.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/lib/copypage_power7.S')
-rw-r--r-- | arch/powerpc/lib/copypage_power7.S | 19 |
1 files changed, 11 insertions, 8 deletions
diff --git a/arch/powerpc/lib/copypage_power7.S b/arch/powerpc/lib/copypage_power7.S index 0ef75bf..395c594 100644 --- a/arch/powerpc/lib/copypage_power7.S +++ b/arch/powerpc/lib/copypage_power7.S @@ -28,13 +28,14 @@ _GLOBAL(copypage_power7) * aligned we don't need to clear the bottom 7 bits of either * address. */ - ori r9,r3,1 /* stream=1 */ + ori r9,r3,1 /* stream=1 => to */ #ifdef CONFIG_PPC_64K_PAGES - lis r7,0x0E01 /* depth=7, units=512 */ + lis r7,0x0E01 /* depth=7 + * units/cachelines=512 */ #else lis r7,0x0E00 /* depth=7 */ - ori r7,r7,0x1000 /* units=32 */ + ori r7,r7,0x1000 /* units/cachelines=32 */ #endif ori r10,r7,1 /* stream=1 */ @@ -43,12 +44,14 @@ _GLOBAL(copypage_power7) .machine push .machine "power4" - dcbt r0,r4,0b01000 - dcbt r0,r7,0b01010 - dcbtst r0,r9,0b01000 - dcbtst r0,r10,0b01010 + /* setup read stream 0 */ + dcbt r0,r4,0b01000 /* addr from */ + dcbt r0,r7,0b01010 /* length and depth from */ + /* setup write stream 1 */ + dcbtst r0,r9,0b01000 /* addr to */ + dcbtst r0,r10,0b01010 /* length and depth to */ eieio - dcbt r0,r8,0b01010 /* GO */ + dcbt r0,r8,0b01010 /* all streams GO */ .machine pop #ifdef CONFIG_ALTIVEC |