[PATCH] powerpc: vdso fixes (take #2)

This fixes various errors in the new functions added in the vDSO's,
I've now verified all functions on both 32 and 64 bits vDSOs. It also
fix a sign extension bug getting the initial time of day at boot that
could cause the monotonic clock value to be completely on bogus for
64 bits applications (with either the vDSO or the syscall) on
powermacs.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

2 files changed, 20 insertions, 12 deletions

diff --git a/arch/powerpc/kernel/vdso64/datapage.S b/arch/powerpc/kernel/vdso64/datapage.S
index e67eda0f8cda..6393e4137bc7 100644
--- a/arch/powerpc/kernel/vdso64/datapage.S
+++ b/arch/powerpc/kernel/vdso64/datapage.S
@@ -80,5 +80,6 @@ V_FUNCTION_BEGIN(__kernel_get_tbfreq)
 	bl	V_LOCAL_FUNC(__get_datapage)
 	ld	r3,CFG_TB_TICKS_PER_SEC(r3)
 	mtlr	r12
+	blr
   .cfi_endproc
 V_FUNCTION_END(__kernel_get_tbfreq)
diff --git a/arch/powerpc/kernel/vdso64/gettimeofday.S b/arch/powerpc/kernel/vdso64/gettimeofday.S
index d371c02a8c0e..1a89094715cc 100644
--- a/arch/powerpc/kernel/vdso64/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso64/gettimeofday.S
@@ -1,4 +1,5 @@
-/*
+
+	/*
  * Userland implementation of gettimeofday() for 64 bits processes in a
  * ppc64 kernel for use in the vDSO
  *
@@ -68,7 +69,7 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
 	/* Check for supported clock IDs */
 	cmpwi	cr0,r3,CLOCK_REALTIME
 	cmpwi	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0,cr0,cr1
+	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
 	bne	cr0,99f
 
 	mflr	r12			/* r12 saves lr */
@@ -84,16 +85,17 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
 
 	bl	V_LOCAL_FUNC(__do_get_xsec)	/* get xsec from tb & kernel */
 
-	lis     r7,0x3b9a		/* r7 = 1000000000 = NSEC_PER_SEC */
-	ori     r7,r7,0xca00
+	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		/* nsec = (xsec * NSEC_PER_SEC) /
+	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
@@ -106,15 +108,16 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
 
 50:	bl	V_LOCAL_FUNC(__do_get_xsec)	/* get xsec from tb & kernel */
 
-	lis     r7,0x3b9a		/* r7 = 1000000000 = NSEC_PER_SEC */
-	ori     r7,r7,0xca00
+	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		/* nsec = (xsec * NSEC_PER_SEC) /
+	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
@@ -123,8 +126,8 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
 	 * can be used
 	 */
 
-	lwz	r4,WTOM_CLOCK_SEC(r9)
-	lwz	r7,WTOM_CLOCK_NSEC(r9)
+	lwa	r4,WTOM_CLOCK_SEC(r3)
+	lwa	r7,WTOM_CLOCK_NSEC(r3)
 
 	/* We now have our result in r4,r7. We create a fake dependency
 	 * on that result and re-check the counter
@@ -144,10 +147,14 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
 	add	r7,r7,r6
 	lis	r9,NSEC_PER_SEC@h
 	ori	r9,r9,NSEC_PER_SEC@l
-	cmpli	cr0,r7,r9
+	cmpl	cr0,r7,r9
+	cmpli	cr1,r7,0
 	blt	1f
 	subf	r7,r9,r7
 	addi	r4,r4,1
+1:	bge	cr1,1f
+	addi	r4,r4,-1
+	add	r7,r7,r9
 1:	std	r4,TSPC64_TV_SEC(r11)
 	std	r7,TSPC64_TV_NSEC(r11)
 
@@ -181,7 +188,7 @@ V_FUNCTION_BEGIN(__kernel_clock_getres)
 	/* Check for supported clock IDs */
 	cmpwi	cr0,r3,CLOCK_REALTIME
 	cmpwi	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0,cr0,cr1
+	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
 	bne	cr0,99f
 
 	li	r3,0