diff options
Diffstat (limited to 'arch/powerpc/kernel/vdso64/gettimeofday.S')
-rw-r--r-- | arch/powerpc/kernel/vdso64/gettimeofday.S | 88 |
1 files changed, 20 insertions, 68 deletions
diff --git a/arch/powerpc/kernel/vdso64/gettimeofday.S b/arch/powerpc/kernel/vdso64/gettimeofday.S index 262cd5857a5..e97a9a0dc4a 100644 --- a/arch/powerpc/kernel/vdso64/gettimeofday.S +++ b/arch/powerpc/kernel/vdso64/gettimeofday.S @@ -33,18 +33,11 @@ V_FUNCTION_BEGIN(__kernel_gettimeofday) bl V_LOCAL_FUNC(__get_datapage) /* get data page */ cmpldi r11,0 /* check if tv is NULL */ beq 2f - bl V_LOCAL_FUNC(__do_get_xsec) /* get xsec from tb & kernel */ - lis r7,15 /* r7 = 1000000 = USEC_PER_SEC */ - ori r7,r7,16960 - rldicl r5,r4,44,20 /* r5 = sec = xsec / XSEC_PER_SEC */ - rldicr r6,r5,20,43 /* r6 = sec * XSEC_PER_SEC */ - std r5,TVAL64_TV_SEC(r11) /* store sec in tv */ - subf r0,r6,r4 /* r0 = xsec = (xsec - r6) */ - mulld r0,r0,r7 /* usec = (xsec * USEC_PER_SEC) / - * XSEC_PER_SEC - */ - rldicl r0,r0,44,20 - std r0,TVAL64_TV_USEC(r11) /* store usec in tv */ + lis r7,1000000@ha /* load up USEC_PER_SEC */ + addi r7,r7,1000000@l + bl V_LOCAL_FUNC(__do_get_tspec) /* get sec/us from tb & kernel */ + std r4,TVAL64_TV_SEC(r11) /* store sec in tv */ + std r5,TVAL64_TV_USEC(r11) /* store usec in tv */ 2: cmpldi r10,0 /* check if tz is NULL */ beq 1f lwz r4,CFG_TZ_MINUTEWEST(r3)/* fill tz */ @@ -77,6 +70,8 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime) .cfi_register lr,r12 mr r11,r4 /* r11 saves tp */ bl V_LOCAL_FUNC(__get_datapage) /* get data page */ + lis r7,NSEC_PER_SEC@h /* want nanoseconds */ + ori r7,r7,NSEC_PER_SEC@l 50: bl V_LOCAL_FUNC(__do_get_tspec) /* get time from tb & kernel */ bne cr1,80f /* if not monotonic, all done */ @@ -171,49 +166,12 @@ V_FUNCTION_END(__kernel_clock_getres) /* - * This is the core of gettimeofday(), it returns the xsec - * value in r4 and expects the datapage ptr (non clobbered) - * in r3. clobbers r0,r4,r5,r6,r7,r8 - * When returning, r8 contains the counter value that can be reused - */ -V_FUNCTION_BEGIN(__do_get_xsec) - .cfi_startproc - /* check for update count & load values */ -1: ld r8,CFG_TB_UPDATE_COUNT(r3) - andi. r0,r8,1 /* pending update ? loop */ - bne- 1b - xor r0,r8,r8 /* create dependency */ - add r3,r3,r0 - - /* Get TB & offset it. We use the MFTB macro which will generate - * workaround code for Cell. - */ - MFTB(r7) - ld r9,CFG_TB_ORIG_STAMP(r3) - subf r7,r9,r7 - - /* Scale result */ - ld r5,CFG_TB_TO_XS(r3) - mulhdu r7,r7,r5 - - /* Add stamp since epoch */ - ld r6,CFG_STAMP_XSEC(r3) - add r4,r6,r7 - - xor r0,r4,r4 - add r3,r3,r0 - ld r0,CFG_TB_UPDATE_COUNT(r3) - cmpld cr0,r0,r8 /* check if updated */ - bne- 1b - blr - .cfi_endproc -V_FUNCTION_END(__do_get_xsec) - -/* - * This is the core of clock_gettime(), it returns the current - * time in seconds and nanoseconds in r4 and r5. + * This is the core of clock_gettime() and gettimeofday(), + * it returns the current time in r4 (seconds) and r5. + * On entry, r7 gives the resolution of r5, either USEC_PER_SEC + * or NSEC_PER_SEC, giving r5 in microseconds or nanoseconds. * It expects the datapage ptr in r3 and doesn't clobber it. - * It clobbers r0 and r6 and returns NSEC_PER_SEC in r7. + * It clobbers r0, r6 and r9. * On return, r8 contains the counter value that can be reused. * This clobbers cr0 but not any other cr field. */ @@ -229,18 +187,18 @@ V_FUNCTION_BEGIN(__do_get_tspec) /* Get TB & offset it. We use the MFTB macro which will generate * workaround code for Cell. */ - MFTB(r7) + MFTB(r6) ld r9,CFG_TB_ORIG_STAMP(r3) - subf r7,r9,r7 + subf r6,r9,r6 /* Scale result */ ld r5,CFG_TB_TO_XS(r3) - sldi r7,r7,12 /* compute time since stamp_xtime */ - mulhdu r6,r7,r5 /* in units of 2^-32 seconds */ + sldi r6,r6,12 /* compute time since stamp_xtime */ + mulhdu r6,r6,r5 /* in units of 2^-32 seconds */ /* Add stamp since epoch */ ld r4,STAMP_XTIME+TSPC64_TV_SEC(r3) - ld r5,STAMP_XTIME+TSPC64_TV_NSEC(r3) + lwz r5,STAMP_SEC_FRAC(r3) or r0,r4,r5 or r0,r0,r6 xor r0,r0,r0 @@ -250,17 +208,11 @@ V_FUNCTION_BEGIN(__do_get_tspec) bne- 1b /* reload if so */ /* convert to seconds & nanoseconds and add to stamp */ - lis r7,NSEC_PER_SEC@h - ori r7,r7,NSEC_PER_SEC@l - mulhwu r0,r6,r7 /* compute nanoseconds and */ + add r6,r6,r5 /* add on fractional seconds of xtime */ + mulhwu r5,r6,r7 /* compute micro or nanoseconds and */ srdi r6,r6,32 /* seconds since stamp_xtime */ - clrldi r0,r0,32 - add r5,r5,r0 /* add nanoseconds together */ - cmpd r5,r7 /* overflow? */ + clrldi r5,r5,32 add r4,r4,r6 - bltlr /* all done if no overflow */ - subf r5,r7,r5 /* if overflow, adjust */ - addi r4,r4,1 blr .cfi_endproc V_FUNCTION_END(__do_get_tspec) |