[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