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author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/arm/lib/memzero.S | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/arm/lib/memzero.S')
-rw-r--r-- | kernel/arch/arm/lib/memzero.S | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/kernel/arch/arm/lib/memzero.S b/kernel/arch/arm/lib/memzero.S new file mode 100644 index 000000000..0eded952e --- /dev/null +++ b/kernel/arch/arm/lib/memzero.S @@ -0,0 +1,137 @@ +/* + * linux/arch/arm/lib/memzero.S + * + * Copyright (C) 1995-2000 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. + */ +#include <linux/linkage.h> +#include <asm/assembler.h> +#include <asm/unwind.h> + + .text + .align 5 + .word 0 +/* + * Align the pointer in r0. r3 contains the number of bytes that we are + * mis-aligned by, and r1 is the number of bytes. If r1 < 4, then we + * don't bother; we use byte stores instead. + */ +UNWIND( .fnstart ) +1: subs r1, r1, #4 @ 1 do we have enough + blt 5f @ 1 bytes to align with? + cmp r3, #2 @ 1 + strltb r2, [r0], #1 @ 1 + strleb r2, [r0], #1 @ 1 + strb r2, [r0], #1 @ 1 + add r1, r1, r3 @ 1 (r1 = r1 - (4 - r3)) +/* + * The pointer is now aligned and the length is adjusted. Try doing the + * memzero again. + */ + +ENTRY(__memzero) + mov r2, #0 @ 1 + ands r3, r0, #3 @ 1 unaligned? + bne 1b @ 1 +/* + * r3 = 0, and we know that the pointer in r0 is aligned to a word boundary. + */ + cmp r1, #16 @ 1 we can skip this chunk if we + blt 4f @ 1 have < 16 bytes + +#if ! CALGN(1)+0 + +/* + * We need an extra register for this loop - save the return address and + * use the LR + */ + str lr, [sp, #-4]! @ 1 +UNWIND( .fnend ) +UNWIND( .fnstart ) +UNWIND( .save {lr} ) + mov ip, r2 @ 1 + mov lr, r2 @ 1 + +3: subs r1, r1, #64 @ 1 write 32 bytes out per loop + stmgeia r0!, {r2, r3, ip, lr} @ 4 + stmgeia r0!, {r2, r3, ip, lr} @ 4 + stmgeia r0!, {r2, r3, ip, lr} @ 4 + stmgeia r0!, {r2, r3, ip, lr} @ 4 + bgt 3b @ 1 + ldmeqfd sp!, {pc} @ 1/2 quick exit +/* + * No need to correct the count; we're only testing bits from now on + */ + tst r1, #32 @ 1 + stmneia r0!, {r2, r3, ip, lr} @ 4 + stmneia r0!, {r2, r3, ip, lr} @ 4 + tst r1, #16 @ 1 16 bytes or more? + stmneia r0!, {r2, r3, ip, lr} @ 4 + ldr lr, [sp], #4 @ 1 +UNWIND( .fnend ) + +#else + +/* + * This version aligns the destination pointer in order to write + * whole cache lines at once. + */ + + stmfd sp!, {r4-r7, lr} +UNWIND( .fnend ) +UNWIND( .fnstart ) +UNWIND( .save {r4-r7, lr} ) + mov r4, r2 + mov r5, r2 + mov r6, r2 + mov r7, r2 + mov ip, r2 + mov lr, r2 + + cmp r1, #96 + andgts ip, r0, #31 + ble 3f + + rsb ip, ip, #32 + sub r1, r1, ip + movs ip, ip, lsl #(32 - 4) + stmcsia r0!, {r4, r5, r6, r7} + stmmiia r0!, {r4, r5} + movs ip, ip, lsl #2 + strcs r2, [r0], #4 + +3: subs r1, r1, #64 + stmgeia r0!, {r2-r7, ip, lr} + stmgeia r0!, {r2-r7, ip, lr} + bgt 3b + ldmeqfd sp!, {r4-r7, pc} + + tst r1, #32 + stmneia r0!, {r2-r7, ip, lr} + tst r1, #16 + stmneia r0!, {r4-r7} + ldmfd sp!, {r4-r7, lr} +UNWIND( .fnend ) + +#endif + +UNWIND( .fnstart ) +4: tst r1, #8 @ 1 8 bytes or more? + stmneia r0!, {r2, r3} @ 2 + tst r1, #4 @ 1 4 bytes or more? + strne r2, [r0], #4 @ 1 +/* + * When we get here, we've got less than 4 bytes to zero. We + * may have an unaligned pointer as well. + */ +5: tst r1, #2 @ 1 2 bytes or more? + strneb r2, [r0], #1 @ 1 + strneb r2, [r0], #1 @ 1 + tst r1, #1 @ 1 a byte left over + strneb r2, [r0], #1 @ 1 + ret lr @ 1 +UNWIND( .fnend ) +ENDPROC(__memzero) |