diff options
Diffstat (limited to 'arch/powerpc/kernel/vdso64/gettimeofday.S')
| -rw-r--r-- | arch/powerpc/kernel/vdso64/gettimeofday.S | 173 |
1 files changed, 81 insertions, 92 deletions
diff --git a/arch/powerpc/kernel/vdso64/gettimeofday.S b/arch/powerpc/kernel/vdso64/gettimeofday.S index c6401f9e37f..a76b4af37ef 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 */ @@ -75,90 +68,51 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime) mflr r12 /* r12 saves lr */ .cfi_register lr,r12 - mr r10,r3 /* r10 saves id */ mr r11,r4 /* r11 saves tp */ bl V_LOCAL_FUNC(__get_datapage) /* get data page */ - beq cr1,50f /* if monotonic -> jump there */ - - /* - * CLOCK_REALTIME - */ - - 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,TSPC64_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 - mulli r0,r0,1000 /* nsec = usec * 1000 */ - std r0,TSPC64_TV_NSEC(r11) /* store nsec in tp */ - - mtlr r12 - crclr cr0*4+so - li r3,0 - blr + 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 */ /* * CLOCK_MONOTONIC */ -50: 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 */ - subf r0,r6,r4 /* r0 = xsec = (xsec - r6) */ - mulld r0,r0,r7 /* usec = (xsec * USEC_PER_SEC) / - * XSEC_PER_SEC - */ - rldicl r6,r0,44,20 - mulli r6,r6,1000 /* nsec = usec * 1000 */ - /* now we must fixup using wall to monotonic. We need to snapshot * that value and do the counter trick again. Fortunately, we still - * have the counter value in r8 that was returned by __do_get_xsec. - * At this point, r5,r6 contain our sec/nsec values. - * can be used + * have the counter value in r8 that was returned by __do_get_tspec. + * At this point, r4,r5 contain our sec/nsec values. */ - lwa r4,WTOM_CLOCK_SEC(r3) - lwa r7,WTOM_CLOCK_NSEC(r3) + lwa r6,WTOM_CLOCK_SEC(r3) + lwa r9,WTOM_CLOCK_NSEC(r3) - /* We now have our result in r4,r7. We create a fake dependency + /* We now have our result in r6,r9. We create a fake dependency * on that result and re-check the counter */ - or r9,r4,r7 - xor r0,r9,r9 + or r0,r6,r9 + xor r0,r0,r0 add r3,r3,r0 ld r0,CFG_TB_UPDATE_COUNT(r3) cmpld cr0,r0,r8 /* check if updated */ bne- 50b - /* Calculate and store result. Note that this mimmics the C code, - * which may cause funny results if nsec goes negative... is that - * possible at all ? + /* Add wall->monotonic offset and check for overflow or underflow. */ - add r4,r4,r5 - add r7,r7,r6 - lis r9,NSEC_PER_SEC@h - ori r9,r9,NSEC_PER_SEC@l - cmpl cr0,r7,r9 - cmpli cr1,r7,0 + add r4,r4,r6 + add r5,r5,r9 + cmpd cr0,r5,r7 + cmpdi cr1,r5,0 blt 1f - subf r7,r9,r7 + subf r5,r7,r5 addi r4,r4,1 -1: bge cr1,1f +1: bge cr1,80f addi r4,r4,-1 - add r7,r7,r9 -1: std r4,TSPC64_TV_SEC(r11) - std r7,TSPC64_TV_NSEC(r11) + add r5,r5,r7 + +80: std r4,TSPC64_TV_SEC(r11) + std r5,TSPC64_TV_NSEC(r11) mtlr r12 crclr cr0*4+so @@ -168,10 +122,6 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime) /* * syscall fallback */ -98: - mtlr r12 - mr r3,r10 - mr r4,r11 99: li r0,__NR_clock_gettime sc @@ -214,14 +164,44 @@ V_FUNCTION_BEGIN(__kernel_clock_getres) .cfi_endproc V_FUNCTION_END(__kernel_clock_getres) +/* + * Exact prototype of time() + * + * time_t time(time *t); + * + */ +V_FUNCTION_BEGIN(__kernel_time) + .cfi_startproc + mflr r12 + .cfi_register lr,r12 + + mr r11,r3 /* r11 holds t */ + bl V_LOCAL_FUNC(__get_datapage) + + ld r4,STAMP_XTIME+TSPC64_TV_SEC(r3) + + cmpldi r11,0 /* check if t is NULL */ + beq 2f + std r4,0(r11) /* store result at *t */ +2: mtlr r12 + crclr cr0*4+so + mr r3,r4 + blr + .cfi_endproc +V_FUNCTION_END(__kernel_time) + /* - * 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 + * 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, r6 and r9. + * On return, r8 contains the counter value that can be reused. + * This clobbers cr0 but not any other cr field. */ -V_FUNCTION_BEGIN(__do_get_xsec) +V_FUNCTION_BEGIN(__do_get_tspec) .cfi_startproc /* check for update count & load values */ 1: ld r8,CFG_TB_UPDATE_COUNT(r3) @@ -233,23 +213,32 @@ V_FUNCTION_BEGIN(__do_get_xsec) /* 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) - mulhdu r7,r7,r5 + sldi r6,r6,12 /* compute time since stamp_xtime */ + mulhdu r6,r6,r5 /* in units of 2^-32 seconds */ /* Add stamp since epoch */ - ld r6,CFG_STAMP_XSEC(r3) - add r4,r6,r7 - - xor r0,r4,r4 + ld r4,STAMP_XTIME+TSPC64_TV_SEC(r3) + lwz r5,STAMP_SEC_FRAC(r3) + or r0,r4,r5 + or r0,r0,r6 + xor r0,r0,r0 add r3,r3,r0 ld r0,CFG_TB_UPDATE_COUNT(r3) - cmpld cr0,r0,r8 /* check if updated */ - bne- 1b + cmpld r0,r8 /* check if updated */ + bne- 1b /* reload if so */ + + /* convert to seconds & nanoseconds and add to stamp */ + 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 r5,r5,32 + add r4,r4,r6 blr .cfi_endproc -V_FUNCTION_END(__do_get_xsec) +V_FUNCTION_END(__do_get_tspec) |