diff options
author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2005-11-11 21:15:21 +1100 |
---|---|---|
committer | Paul Mackerras <paulus@samba.org> | 2005-11-11 22:25:39 +1100 |
commit | a7f290dad32ee34d931561b7943c858fe2aae503 (patch) | |
tree | 850f04ed9ffba8aef6e151fa9c9e8a0c667bb795 /arch/ppc64/kernel/vdso32/gettimeofday.S | |
parent | 6761c4a07378e19e3710bb69cea65795774529b1 (diff) |
[PATCH] powerpc: Merge vdso's and add vdso support to 32 bits kernel
This patch moves the vdso's to arch/powerpc, adds support for the 32
bits vdso to the 32 bits kernel, rename systemcfg (finally !), and adds
some new (still untested) routines to both vdso's: clock_gettime() with
support for CLOCK_REALTIME and CLOCK_MONOTONIC, clock_getres() (same
clocks) and get_tbfreq() for glibc to retreive the timebase frequency.
Tom,Steve: The implementation of get_tbfreq() I've done for 32 bits
returns a long long (r3, r4) not a long. This is such that if we ever
add support for >4Ghz timebases on ppc32, the userland interface won't
have to change.
I have tested gettimeofday() using some glibc patches in both ppc32 and
ppc64 kernels using 32 bits userland (I haven't had a chance to test a
64 bits userland yet, but the implementation didn't change and was
tested earlier). I haven't tested yet the new functions.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/ppc64/kernel/vdso32/gettimeofday.S')
-rw-r--r-- | arch/ppc64/kernel/vdso32/gettimeofday.S | 140 |
1 files changed, 0 insertions, 140 deletions
diff --git a/arch/ppc64/kernel/vdso32/gettimeofday.S b/arch/ppc64/kernel/vdso32/gettimeofday.S deleted file mode 100644 index e243c1d24af7..000000000000 --- a/arch/ppc64/kernel/vdso32/gettimeofday.S +++ /dev/null @@ -1,140 +0,0 @@ -/* - * Userland implementation of gettimeofday() for 32 bits processes in a - * ppc64 kernel for use in the vDSO - * - * Copyright (C) 2004 Benjamin Herrenschmuidt (benh@kernel.crashing.org), IBM Corp. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - */ -#include <linux/config.h> -#include <asm/processor.h> -#include <asm/ppc_asm.h> -#include <asm/vdso.h> -#include <asm/asm-offsets.h> -#include <asm/unistd.h> - - .text -/* - * Exact prototype of gettimeofday - * - * int __kernel_gettimeofday(struct timeval *tv, struct timezone *tz); - * - */ -V_FUNCTION_BEGIN(__kernel_gettimeofday) - .cfi_startproc - mflr r12 - .cfi_register lr,r12 - - mr r10,r3 /* r10 saves tv */ - mr r11,r4 /* r11 saves tz */ - bl __get_datapage@local /* get data page */ - mr r9, r3 /* datapage ptr in r9 */ - bl __do_get_xsec@local /* get xsec from tb & kernel */ - bne- 2f /* out of line -> do syscall */ - - /* seconds are xsec >> 20 */ - rlwinm r5,r4,12,20,31 - rlwimi r5,r3,12,0,19 - stw r5,TVAL32_TV_SEC(r10) - - /* get remaining xsec and convert to usec. we scale - * up remaining xsec by 12 bits and get the top 32 bits - * of the multiplication - */ - rlwinm r5,r4,12,0,19 - lis r6,1000000@h - ori r6,r6,1000000@l - mulhwu r5,r5,r6 - stw r5,TVAL32_TV_USEC(r10) - - cmpli cr0,r11,0 /* check if tz is NULL */ - beq 1f - lwz r4,CFG_TZ_MINUTEWEST(r9)/* fill tz */ - lwz r5,CFG_TZ_DSTTIME(r9) - stw r4,TZONE_TZ_MINWEST(r11) - stw r5,TZONE_TZ_DSTTIME(r11) - -1: mtlr r12 - li r3,0 - blr - -2: mr r3,r10 - mr r4,r11 - li r0,__NR_gettimeofday - sc - b 1b - .cfi_endproc -V_FUNCTION_END(__kernel_gettimeofday) - -/* - * This is the core of gettimeofday(), it returns the xsec - * value in r3 & r4 and expects the datapage ptr (non clobbered) - * in r9. clobbers r0,r4,r5,r6,r7,r8 -*/ -__do_get_xsec: - .cfi_startproc - /* Check for update count & load values. We use the low - * order 32 bits of the update count - */ -1: lwz r8,(CFG_TB_UPDATE_COUNT+4)(r9) - andi. r0,r8,1 /* pending update ? loop */ - bne- 1b - xor r0,r8,r8 /* create dependency */ - add r9,r9,r0 - - /* Load orig stamp (offset to TB) */ - lwz r5,CFG_TB_ORIG_STAMP(r9) - lwz r6,(CFG_TB_ORIG_STAMP+4)(r9) - - /* Get a stable TB value */ -2: mftbu r3 - mftbl r4 - mftbu r0 - cmpl cr0,r3,r0 - bne- 2b - - /* Substract tb orig stamp. If the high part is non-zero, we jump to the - * slow path which call the syscall. If it's ok, then we have our 32 bits - * tb_ticks value in r7 - */ - subfc r7,r6,r4 - subfe. r0,r5,r3 - bne- 3f - - /* Load scale factor & do multiplication */ - lwz r5,CFG_TB_TO_XS(r9) /* load values */ - lwz r6,(CFG_TB_TO_XS+4)(r9) - mulhwu r4,r7,r5 - mulhwu r6,r7,r6 - mullw r0,r7,r5 - addc r6,r6,r0 - - /* At this point, we have the scaled xsec value in r4 + XER:CA - * we load & add the stamp since epoch - */ - lwz r5,CFG_STAMP_XSEC(r9) - lwz r6,(CFG_STAMP_XSEC+4)(r9) - adde r4,r4,r6 - addze r3,r5 - - /* We now have our result in r3,r4. We create a fake dependency - * on that result and re-check the counter - */ - xor r0,r4,r4 - add r9,r9,r0 - lwz r0,(CFG_TB_UPDATE_COUNT+4)(r9) - cmpl cr0,r8,r0 /* check if updated */ - bne- 1b - - /* Warning ! The caller expects CR:EQ to be set to indicate a - * successful calculation (so it won't fallback to the syscall - * method). We have overriden that CR bit in the counter check, - * but fortunately, the loop exit condition _is_ CR:EQ set, so - * we can exit safely here. If you change this code, be careful - * of that side effect. - */ -3: blr - .cfi_endproc |