diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2008-01-29 08:52:50 +1100 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-01-29 08:52:50 +1100 |
commit | e189f3495c4e30fc84fc9241096edf3932e23439 (patch) | |
tree | 5916c89ace81537a02ae01869386ba6caafdab9c /arch/sh/lib64/clear_page.S | |
parent | f4798748dee00c807a63f5518f08b3df161e0f6d (diff) | |
parent | 6582d7b7376aa587d74b08c74457dc28abc1a9fa (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (197 commits)
sh: add spi header and r2d platform data V3
sh: update r7780rp interrupt code
sh: remove consistent alloc stuff from the machine vector
sh: use declared coherent memory for dreamcast pci ethernet adapter
sh: declared coherent memory support V2
sh: Add support for SDK7780 board.
sh: constify function pointer tables
sh: Kill off -traditional for linker script.
cdrom: Add support for Sega Dreamcast GD-ROM.
sh: Kill off hs7751rvoip reference from arch/sh/Kconfig.
sh: Drop r7780rp_defconfig, use r7780mp_defconfig as kbuild default.
sh: Kill off dead HS771RVoIP board support.
sh: r7785rp: Fix up DECLARE_INTC_DESC() arg mismatch.
sh: r7785rp: Hook up the rest of the HL7785 FPGA IRQ vectors.
sh: r2d - enable sm501 usb host function
sh: remove voyagergx
sh: r2d - add lcd planel timings to sm501 platform data
sh: Add OHCI and UDC platform devices for SH7720.
sh: intc - remove default interrupt priority tables
sh: Correct pte size mismatch for X2 TLB.
...
Diffstat (limited to 'arch/sh/lib64/clear_page.S')
-rw-r--r-- | arch/sh/lib64/clear_page.S | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/arch/sh/lib64/clear_page.S b/arch/sh/lib64/clear_page.S new file mode 100644 index 00000000000..007ab48ecc1 --- /dev/null +++ b/arch/sh/lib64/clear_page.S @@ -0,0 +1,54 @@ +/* + Copyright 2003 Richard Curnow, SuperH (UK) Ltd. + + This file is subject to the terms and conditions of the GNU General Public + License. See the file "COPYING" in the main directory of this archive + for more details. + + Tight version of memset for the case of just clearing a page. It turns out + that having the alloco's spaced out slightly due to the increment/branch + pair causes them to contend less for access to the cache. Similarly, + keeping the stores apart from the allocos causes less contention. => Do two + separate loops. Do multiple stores per loop to amortise the + increment/branch cost a little. + + Parameters: + r2 : source effective address (start of page) + + Always clears 4096 bytes. + + Note : alloco guarded by synco to avoid TAKum03020 erratum + +*/ + + .section .text..SHmedia32,"ax" + .little + + .balign 8 + .global clear_page +clear_page: + pta/l 1f, tr1 + pta/l 2f, tr2 + ptabs/l r18, tr0 + + movi 4096, r7 + add r2, r7, r7 + add r2, r63, r6 +1: + alloco r6, 0 + synco ! TAKum03020 + addi r6, 32, r6 + bgt/l r7, r6, tr1 + + add r2, r63, r6 +2: + st.q r6, 0, r63 + st.q r6, 8, r63 + st.q r6, 16, r63 + st.q r6, 24, r63 + addi r6, 32, r6 + bgt/l r7, r6, tr2 + + blink tr0, r63 + + |