X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/21362eb3e66fd2c787aee132bce100a44d71a99c..4a3eedf9ecc9bbe3f3a5c6ce5e53ad199d639d32:/osfmk/ppc/commpage/gettimeofday.s diff --git a/osfmk/ppc/commpage/gettimeofday.s b/osfmk/ppc/commpage/gettimeofday.s index e92b9f846..e9645ee37 100644 --- a/osfmk/ppc/commpage/gettimeofday.s +++ b/osfmk/ppc/commpage/gettimeofday.s @@ -1,5 +1,5 @@ /* - * Copyright (c) 2003 Apple Computer, Inc. All rights reserved. + * Copyright (c) 2003-2005 Apple Computer, Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * @@ -26,15 +26,11 @@ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ -#define ASSEMBLER #include #include // EXT, LEXT #include #include -#define USEC_PER_SEC 1000000 - - /* The red zone is used to move data between GPRs and FPRs: */ #define rzTicks -8 // elapsed ticks since timestamp (double) @@ -54,7 +50,7 @@ // in user mode, usually without having to make a system call. We do not deal with // the timezone. The kernel maintains the following values in the comm page: // -// _COMM_PAGE_TIMESTAMP = a BSD-style pair of uint_32's for seconds and microseconds +// _COMM_PAGE_TIMESTAMP = 64 bit seconds timestamp // // _COMM_PAGE_TIMEBASE = the timebase at which the timestamp was valid // @@ -75,8 +71,7 @@ gettimeofday_32: // int gettimeofday(timeval *tp); 0: lwz r5,_COMM_PAGE_TIMEBASE+0(0) // r5,r6 = TBR at timestamp lwz r6,_COMM_PAGE_TIMEBASE+4(0) - lwz r7,_COMM_PAGE_TIMESTAMP+0(0) // r7 = timestamp seconds - lwz r8,_COMM_PAGE_TIMESTAMP+4(0) // r8 = timestamp microseconds + lwz r8,_COMM_PAGE_TIMESTAMP+4(0) // r8 = timestamp 32 bit seconds lfd f1,_COMM_PAGE_SEC_PER_TICK(0) 1: mftbu r10 // r10,r11 = current timebase @@ -90,31 +85,28 @@ gettimeofday_32: // int gettimeofday(timeval *tp); lwz r0,_COMM_PAGE_TIMEBASE+0(0) // then load data a 2nd time lwz r12,_COMM_PAGE_TIMEBASE+4(0) - lwz r2,_COMM_PAGE_TIMESTAMP+0(0) lwz r9,_COMM_PAGE_TIMESTAMP+4(0) cmplw cr6,r5,r0 // did we read a consistent set? cmplw cr7,r6,r12 beq- 3f // timestamp is disabled so return bad status - cmplw cr1,r2,r7 cmplw cr5,r9,r8 crand cr0_eq,cr6_eq,cr7_eq - crand cr1_eq,cr1_eq,cr5_eq - crand cr0_eq,cr0_eq,cr1_eq + crand cr0_eq,cr0_eq,cr5_eq bne- 0b // loop until we have a consistent set of data subfc r11,r6,r11 // compute ticks since timestamp lwz r9,_COMM_PAGE_2_TO_52(0) // get exponent for (2**52) subfe r10,r5,r10 // complete 64-bit subtract - lfd f2,_COMM_PAGE_2_TO_52(0) // f3 <- (2**52) + lfd f2,_COMM_PAGE_2_TO_52(0) // f2 <- (2**52) srwi. r0,r10,2 // if more than 2**34 ticks have elapsed... stw r11,rzTicks+4(r1) // store elapsed ticks into red zone or r10,r10,r9 // convert long-long in (r10,r11) into double bne- 3f // ...call kernel to reprime timestamp stw r10,rzTicks(r1) // complete double - lis r12,hi16(USEC_PER_SEC) - ori r12,r12,lo16(USEC_PER_SEC) - + + mffs f7 + mtfsfi 7,1 lfd f3,rzTicks(r1) // get elapsed ticks since timestamp + 2**52 fsub f4,f3,f2 // subtract 2**52 and normalize fmul f5,f4,f1 // f5 <- elapsed seconds since timestamp @@ -128,19 +120,14 @@ gettimeofday_32: // int gettimeofday(timeval *tp); fmul f6,f6,f3 // f6 <- fractional elapsed useconds fctiwz f6,f6 // convert useconds to integer stfd f6,rzUSeconds(r1) // store useconds into red zone + mtfsf 0xff,f7 lwz r5,rzSeconds+4(r1) // r5 <- seconds since timestamp - lwz r6,rzUSeconds+4(r1) // r6 <- useconds since timestamp - add r7,r7,r5 // add elapsed seconds to timestamp seconds - add r8,r8,r6 // ditto useconds + lwz r7,rzUSeconds+4(r1) // r7 <- useconds since timestamp + add r6,r8,r5 // add elapsed seconds to timestamp seconds - cmplw r8,r12 // r8 >= USEC_PER_SEC ? - blt 2f // no - addi r7,r7,1 // add 1 to secs - sub r8,r8,r12 // subtract USEC_PER_SEC from usecs -2: - stw r7,0(r3) // store secs//usecs into user's timeval - stw r8,4(r3) + stw r6,0(r3) // store secs//usecs into user's timeval + stw r7,4(r3) li r3,0 // return success blr 3: // too long since last timestamp or this code is disabled @@ -155,12 +142,12 @@ gettimeofday_32: // int gettimeofday(timeval *tp); // *************************************** // // This routine is called in 32-bit mode on 64-bit processors. A timeval is a struct of -// a long seconds and int useconds, so it's size depends on mode. +// a long seconds and int useconds, so its size depends on mode. gettimeofday_g5_32: // int gettimeofday(timeval *tp); 0: ld r6,_COMM_PAGE_TIMEBASE(0) // r6 = TBR at timestamp - ld r8,_COMM_PAGE_TIMESTAMP(0) // r8 = timestamp (seconds,useconds) + ld r8,_COMM_PAGE_TIMESTAMP(0) // r8 = timestamp (seconds) lfd f1,_COMM_PAGE_SEC_PER_TICK(0) mftb r10 // r10 = get current timebase lwsync // create a barrier if MP (patched to NOP if UP) @@ -178,6 +165,8 @@ gettimeofday_g5_32: // int gettimeofday(timeval *tp); std r11,rzTicks(r1) // put ticks in redzone where we can "lfd" it bne-- 3f // timestamp too old, so reprime + mffs f7 + mtfsfi 7,1 lfd f3,rzTicks(r1) // get elapsed ticks since timestamp (fixed pt) fcfid f4,f3 // float the tick count fmul f5,f4,f1 // f5 <- elapsed seconds since timestamp @@ -189,22 +178,14 @@ gettimeofday_g5_32: // int gettimeofday(timeval *tp); fmul f6,f6,f3 // f6 <- fractional elapsed useconds fctidz f6,f6 // convert useconds to fixed pt integer stfd f6,rzUSeconds(r1) // store useconds into red zone + mtfsf 0xff,f7 - lis r12,hi16(USEC_PER_SEC) // r12 <- 10**6 - srdi r7,r8,32 // extract seconds from doubleword timestamp lwz r5,rzSeconds+4(r1) // r5 <- seconds since timestamp - ori r12,r12,lo16(USEC_PER_SEC) - lwz r6,rzUSeconds+4(r1) // r6 <- useconds since timestamp - add r7,r7,r5 // add elapsed seconds to timestamp seconds - add r8,r8,r6 // ditto useconds + lwz r7,rzUSeconds+4(r1) // r7 <- useconds since timestamp + add r6,r8,r5 // add elapsed seconds to timestamp seconds - cmplw r8,r12 // r8 >= USEC_PER_SEC ? - blt 2f // no - addi r7,r7,1 // add 1 to secs - sub r8,r8,r12 // subtract USEC_PER_SEC from usecs -2: - stw r7,0(r3) // store secs//usecs into user's timeval - stw r8,4(r3) + stw r6,0(r3) // store secs//usecs into user's timeval + stw r7,4(r3) li r3,0 // return success blr 3: // too long since last timestamp or this code is disabled @@ -219,12 +200,12 @@ gettimeofday_g5_32: // int gettimeofday(timeval *tp); // *************************************** // // This routine is called in 64-bit mode on 64-bit processors. A timeval is a struct of -// a long seconds and int useconds, so it's size depends on mode. +// a long seconds and int useconds, so its size depends on mode. gettimeofday_g5_64: // int gettimeofday(timeval *tp); 0: ld r6,_COMM_PAGE_TIMEBASE(0) // r6 = TBR at timestamp - ld r8,_COMM_PAGE_TIMESTAMP(0) // r8 = timestamp (seconds,useconds) + ld r8,_COMM_PAGE_TIMESTAMP(0) // r8 = timestamp (seconds) lfd f1,_COMM_PAGE_SEC_PER_TICK(0) mftb r10 // r10 = get current timebase lwsync // create a barrier if MP (patched to NOP if UP) @@ -242,6 +223,8 @@ gettimeofday_g5_64: // int gettimeofday(timeval *tp); std r11,rzTicks(r1) // put ticks in redzone where we can "lfd" it bne-- 3f // timestamp too old, so reprime + mffs f7 + mtfsfi 7,1 lfd f3,rzTicks(r1) // get elapsed ticks since timestamp (fixed pt) fcfid f4,f3 // float the tick count fmul f5,f4,f1 // f5 <- elapsed seconds since timestamp @@ -253,22 +236,14 @@ gettimeofday_g5_64: // int gettimeofday(timeval *tp); fmul f6,f6,f3 // f6 <- fractional elapsed useconds fctidz f6,f6 // convert useconds to fixed pt integer stfd f6,rzUSeconds(r1) // store useconds into red zone + mtfsf 0xff,f7 - lis r12,hi16(USEC_PER_SEC) // r12 <- 10**6 - srdi r7,r8,32 // extract seconds from doubleword timestamp lwz r5,rzSeconds+4(r1) // r5 <- seconds since timestamp - ori r12,r12,lo16(USEC_PER_SEC) - lwz r6,rzUSeconds+4(r1) // r6 <- useconds since timestamp - add r7,r7,r5 // add elapsed seconds to timestamp seconds - add r8,r8,r6 // ditto useconds + lwz r7,rzUSeconds+4(r1) // r7 <- useconds since timestamp + add r6,r8,r5 // add elapsed seconds to timestamp seconds - cmplw r8,r12 // r8 >= USEC_PER_SEC ? - blt 2f // no - addi r7,r7,1 // add 1 to secs - sub r8,r8,r12 // subtract USEC_PER_SEC from usecs -2: - std r7,0(r3) // store secs//usecs into user's timeval - stw r8,8(r3) + std r6,0(r3) // store secs//usecs into user's timeval + stw r7,8(r3) li r3,0 // return success blr 3: // too long since last timestamp or this code is disabled