Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 139 insertions, 0 deletions

diff --git a/arch/ppc64/kernel/vdso32/gettimeofday.S b/arch/ppc64/kernel/vdso32/gettimeofday.S
new file mode 100644
index 000000000000..ca7f415195c4
--- /dev/null
+++ b/arch/ppc64/kernel/vdso32/gettimeofday.S
@@ -0,0 +1,139 @@
+/*
+ * 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/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
+	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	r6,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