[PATCH] powerpc: Merge vdso's and add vdso support to 32 bits kernel

This patch moves the vdso's to arch/powerpc, adds support for the 32
bits vdso to the 32 bits kernel, rename systemcfg (finally !), and adds
some new (still untested) routines to both vdso's: clock_gettime() with
support for CLOCK_REALTIME and CLOCK_MONOTONIC, clock_getres() (same
clocks) and get_tbfreq() for glibc to retreive the timebase frequency.

Tom,Steve: The implementation of get_tbfreq() I've done for 32 bits
returns a long long (r3, r4) not a long. This is such that if we ever
add support for >4Ghz timebases on ppc32, the userland interface won't
have to change.

I have tested gettimeofday() using some glibc patches in both ppc32 and
ppc64 kernels using 32 bits userland (I haven't had a chance to test a
64 bits userland yet, but the implementation didn't change and was
tested earlier). I haven't tested yet the new functions.

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

8 files changed, 961 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/vdso32/Makefile b/arch/powerpc/kernel/vdso32/Makefile
new file mode 100644
index 00000000000..758331d4d1a
--- /dev/null
+++ b/arch/powerpc/kernel/vdso32/Makefile
@@ -0,0 +1,40 @@
+
+# List of files in the vdso, has to be asm only for now
+
+obj-vdso32 = sigtramp.o gettimeofday.o datapage.o cacheflush.o note.o
+
+# Build rules
+
+ifeq ($(CONFIG_PPC32),y)
+CROSS32CC := $(CC)
+endif
+
+targets := $(obj-vdso32) vdso32.so
+obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32))
+
+
+EXTRA_CFLAGS := -shared -s -fno-common -fno-builtin
+EXTRA_CFLAGS += -nostdlib -Wl,-soname=linux-vdso32.so.1
+EXTRA_AFLAGS := -D__VDSO32__ -s
+
+obj-y += vdso32_wrapper.o
+extra-y += vdso32.lds
+CPPFLAGS_vdso32.lds += -P -C -U$(ARCH)
+
+# Force dependency (incbin is bad)
+$(obj)/vdso32_wrapper.o : $(obj)/vdso32.so
+
+# link rule for the .so file, .lds has to be first
+$(obj)/vdso32.so: $(src)/vdso32.lds $(obj-vdso32)
+	$(call if_changed,vdso32ld)
+
+# assembly rules for the .S files
+$(obj-vdso32): %.o: %.S
+	$(call if_changed_dep,vdso32as)
+
+# actual build commands
+quiet_cmd_vdso32ld = VDSO32L $@
+      cmd_vdso32ld = $(CROSS32CC) $(c_flags) -Wl,-T $^ -o $@
+quiet_cmd_vdso32as = VDSO32A $@
+      cmd_vdso32as = $(CROSS32CC) $(a_flags) -c -o $@ $<
+
diff --git a/arch/powerpc/kernel/vdso32/cacheflush.S b/arch/powerpc/kernel/vdso32/cacheflush.S
new file mode 100644
index 00000000000..c8db993574e
--- /dev/null
+++ b/arch/powerpc/kernel/vdso32/cacheflush.S
@@ -0,0 +1,67 @@
+/*
+ * vDSO provided cache flush routines
+ *
+ * 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/asm-offsets.h>
+
+	.text
+
+/*
+ * Default "generic" version of __kernel_sync_dicache.
+ *
+ * void __kernel_sync_dicache(unsigned long start, unsigned long end)
+ *
+ * Flushes the data cache & invalidate the instruction cache for the
+ * provided range [start, end[
+ *
+ * Note: all CPUs supported by this kernel have a 128 bytes cache
+ * line size so we don't have to peek that info from the datapage
+ */
+V_FUNCTION_BEGIN(__kernel_sync_dicache)
+  .cfi_startproc
+	li	r5,127
+	andc	r6,r3,r5		/* round low to line bdy */
+	subf	r8,r6,r4		/* compute length */
+	add	r8,r8,r5		/* ensure we get enough */
+	srwi.	r8,r8,7			/* compute line count */
+	beqlr				/* nothing to do? */
+	mtctr	r8
+	mr	r3,r6
+1:	dcbst	0,r3
+	addi	r3,r3,128
+	bdnz	1b
+	sync
+	mtctr	r8
+1:	icbi	0,r6
+	addi	r6,r6,128
+	bdnz	1b
+	isync
+	li	r3,0
+	blr
+  .cfi_endproc
+V_FUNCTION_END(__kernel_sync_dicache)
+
+
+/*
+ * POWER5 version of __kernel_sync_dicache
+ */
+V_FUNCTION_BEGIN(__kernel_sync_dicache_p5)
+  .cfi_startproc
+	sync
+	isync
+	li	r3,0
+	blr
+  .cfi_endproc
+V_FUNCTION_END(__kernel_sync_dicache_p5)
+
diff --git a/arch/powerpc/kernel/vdso32/datapage.S b/arch/powerpc/kernel/vdso32/datapage.S
new file mode 100644
index 00000000000..a08c26e8783
--- /dev/null
+++ b/arch/powerpc/kernel/vdso32/datapage.S
@@ -0,0 +1,84 @@
+/*
+ * Access to the shared data page by the vDSO & syscall map
+ *
+ * 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/asm-offsets.h>
+#include <asm/unistd.h>
+#include <asm/vdso.h>
+
+	.text
+V_FUNCTION_BEGIN(__get_datapage)
+  .cfi_startproc
+	/* We don't want that exposed or overridable as we want other objects
+	 * to be able to bl directly to here
+	 */
+	.protected __get_datapage
+	.hidden __get_datapage
+
+	mflr	r0
+  .cfi_register lr,r0
+
+	bcl	20,31,1f
+	.global	__kernel_datapage_offset;
+__kernel_datapage_offset:
+	.long	0
+1:
+	mflr	r3
+	mtlr	r0
+	lwz	r0,0(r3)
+	add	r3,r0,r3
+	blr
+  .cfi_endproc
+V_FUNCTION_END(__get_datapage)
+
+/*
+ * void *__kernel_get_syscall_map(unsigned int *syscall_count) ;
+ *
+ * returns a pointer to the syscall map. the map is agnostic to the
+ * size of "long", unlike kernel bitops, it stores bits from top to
+ * bottom so that memory actually contains a linear bitmap
+ * check for syscall N by testing bit (0x80000000 >> (N & 0x1f)) of
+ * 32 bits int at N >> 5.
+ */
+V_FUNCTION_BEGIN(__kernel_get_syscall_map)
+  .cfi_startproc
+	mflr	r12
+  .cfi_register lr,r12
+
+	mr	r4,r3
+	bl	__get_datapage@local
+	mtlr	r12
+	addi	r3,r3,CFG_SYSCALL_MAP32
+	cmpli	cr0,r4,0
+	beqlr
+	li	r0,__NR_syscalls
+	stw	r0,0(r4)
+	blr
+  .cfi_endproc
+V_FUNCTION_END(__kernel_get_syscall_map)
+
+/*
+ * void unsigned long long  __kernel_get_tbfreq(void);
+ *
+ * returns the timebase frequency in HZ
+ */
+V_FUNCTION_BEGIN(__kernel_get_tbfreq)
+  .cfi_startproc
+	mflr	r12
+  .cfi_register lr,r12
+	bl	__get_datapage@local
+	lwz	r3,CFG_TB_TICKS_PER_SEC(r3)
+	lwz	r4,(CFG_TB_TICKS_PER_SEC + 4)(r3)
+	mtlr	r12
+  .cfi_endproc
+V_FUNCTION_END(__kernel_get_tbfreq)
diff --git a/arch/powerpc/kernel/vdso32/gettimeofday.S b/arch/powerpc/kernel/vdso32/gettimeofday.S
new file mode 100644
index 00000000000..aeb5fc9b87b
--- /dev/null
+++ b/arch/powerpc/kernel/vdso32/gettimeofday.S
@@ -0,0 +1,315 @@
+/*
+ * 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/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
+	li	r3,0
+	blr
+
+2:
+	mtlr	r12
+	mr	r3,r10
+	mr	r4,r11
+	li	r0,__NR_gettimeofday
+	sc
+	blr
+  .cfi_endproc
+V_FUNCTION_END(__kernel_gettimeofday)
+
+/*
+ * Exact prototype of clock_gettime()
+ *
+ * int __kernel_clock_gettime(clockid_t clock_id, struct timespec *tp);
+ *
+ */
+V_FUNCTION_BEGIN(__kernel_clock_gettime)
+  .cfi_startproc
+	/* Check for supported clock IDs */
+	cmpli	cr0,r3,CLOCK_REALTIME
+	cmpli	cr1,r3,CLOCK_MONOTONIC
+	cror	cr0,cr0,cr1
+	bne	cr0,99f
+
+	mflr	r12			/* r12 saves lr */
+  .cfi_register lr,r12
+	mr	r10,r3			/* r10 saves id */
+	mr	r11,r4			/* r11 saves tp */
+	bl	__get_datapage@local	/* get data page */
+	mr	r9, r3			/* datapage ptr in r9 */
+	beq	cr1,50f			/* if monotonic -> jump there */
+
+	/*
+	 * CLOCK_REALTIME
+	 */
+
+	bl	__do_get_xsec@local	/* get xsec from tb & kernel */
+	bne-	98f			/* out of line -> do syscall */
+
+	/* seconds are xsec >> 20 */
+	rlwinm	r5,r4,12,20,31
+	rlwimi	r5,r3,12,0,19
+	stw	r5,TSPC32_TV_SEC(r11)
+
+	/* get remaining xsec and convert to nsec. we scale
+	 * up remaining xsec by 12 bits and get the top 32 bits
+	 * of the multiplication, then we multiply by 1000
+	 */
+	rlwinm	r5,r4,12,0,19
+	lis	r6,1000000@h
+	ori	r6,r6,1000000@l
+	mulhwu	r5,r5,r6
+	mulli	r5,r5,1000
+	stw	r5,TSPC32_TV_NSEC(r11)
+	mtlr	r12
+	li	r3,0
+	blr
+
+	/*
+	 * CLOCK_MONOTONIC
+	 */
+
+50:	bl	__do_get_xsec@local	/* get xsec from tb & kernel */
+	bne-	98f			/* out of line -> do syscall */
+
+	/* seconds are xsec >> 20 */
+	rlwinm	r6,r4,12,20,31
+	rlwimi	r6,r3,12,0,19
+
+	/* get remaining xsec and convert to nsec. we scale
+	 * up remaining xsec by 12 bits and get the top 32 bits
+	 * of the multiplication, then we multiply by 1000
+	 */
+	rlwinm	r7,r4,12,0,19
+	lis	r5,1000000@h
+	ori	r5,r5,1000000@l
+	mulhwu	r7,r7,r5
+	mulli	r7,r7,1000
+
+	/* 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, r6,r7 contain our sec/nsec values, r3,r4 and r5
+	 * can be used
+	 */
+
+	lwz	r3,WTOM_CLOCK_SEC(r9)
+	lwz	r4,WTOM_CLOCK_NSEC(r9)
+
+	/* We now have our result in r3,r4. We create a fake dependency
+	 * on that result and re-check the counter
+	 */
+	or	r5,r4,r3
+	xor	r0,r5,r5
+	add	r9,r9,r0
+#ifdef CONFIG_PPC64
+	lwz	r0,(CFG_TB_UPDATE_COUNT+4)(r9)
+#else
+	lwz	r0,(CFG_TB_UPDATE_COUNT)(r9)
+#endif
+        cmpl    cr0,r8,r0		/* 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	r3,r3,r6
+	add	r4,r4,r7
+	lis	r5,NSEC_PER_SEC@h
+	ori	r5,r5,NSEC_PER_SEC@l
+	cmpli	cr0,r4,r5
+	blt	1f
+	subf	r4,r5,r4
+	addi	r3,r3,1
+1:	stw	r3,TSPC32_TV_SEC(r11)
+	stw	r4,TSPC32_TV_NSEC(r11)
+
+	mtlr	r12
+	li	r3,0
+	blr
+
+	/*
+	 * syscall fallback
+	 */
+98:
+	mtlr	r12
+	mr	r3,r10
+	mr	r4,r11
+99:
+	li	r0,__NR_clock_gettime
+	sc
+	blr
+  .cfi_endproc
+V_FUNCTION_END(__kernel_clock_gettime)
+
+
+/*
+ * Exact prototype of clock_getres()
+ *
+ * int __kernel_clock_getres(clockid_t clock_id, struct timespec *res);
+ *
+ */
+V_FUNCTION_BEGIN(__kernel_clock_getres)
+  .cfi_startproc
+	/* Check for supported clock IDs */
+	cmpwi	cr0,r3,CLOCK_REALTIME
+	cmpwi	cr1,r3,CLOCK_MONOTONIC
+	cror	cr0,cr0,cr1
+	bne	cr0,99f
+
+	li	r3,0
+	cmpli	cr0,r4,0
+	beqlr
+	lis	r5,CLOCK_REALTIME_RES@h
+	ori	r5,r5,CLOCK_REALTIME_RES@l
+	stw	r3,TSPC32_TV_SEC(r4)
+	stw	r5,TSPC32_TV_NSEC(r4)
+	blr
+
+	/*
+	 * syscall fallback
+	 */
+99:
+	li	r0,__NR_clock_getres
+	sc
+	blr
+  .cfi_endproc
+V_FUNCTION_END(__kernel_clock_getres)
+
+
+/*
+ * This is the core of gettimeofday() & friends, it returns the xsec
+ * value in r3 & r4 and expects the datapage ptr (non clobbered)
+ * in r9. clobbers r0,r4,r5,r6,r7,r8.
+ * When returning, r8 contains the counter value that can be reused
+ * by the monotonic clock implementation
+ */
+__do_get_xsec:
+  .cfi_startproc
+	/* Check for update count & load values. We use the low
+	 * order 32 bits of the update count
+	 */
+#ifdef CONFIG_PPC64
+1:	lwz	r8,(CFG_TB_UPDATE_COUNT+4)(r9)
+#else
+1:	lwz	r8,(CFG_TB_UPDATE_COUNT)(r9)
+#endif
+	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	r0,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
+	 */
+	or	r6,r4,r3
+	xor	r0,r6,r6
+	add	r9,r9,r0
+#ifdef CONFIG_PPC64
+	lwz	r0,(CFG_TB_UPDATE_COUNT+4)(r9)
+#else
+	lwz	r0,(CFG_TB_UPDATE_COUNT)(r9)
+#endif
+        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
diff --git a/arch/powerpc/kernel/vdso32/note.S b/arch/powerpc/kernel/vdso32/note.S
new file mode 100644
index 00000000000..d4b5be4f3d5
--- /dev/null
+++ b/arch/powerpc/kernel/vdso32/note.S
@@ -0,0 +1,25 @@
+/*
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
+ * Here we can supply some information useful to userland.
+ */
+
+#include <linux/uts.h>
+#include <linux/version.h>
+
+#define ASM_ELF_NOTE_BEGIN(name, flags, vendor, type)			      \
+	.section name, flags;						      \
+	.balign 4;							      \
+	.long 1f - 0f;		/* name length */			      \
+	.long 3f - 2f;		/* data length */			      \
+	.long type;		/* note type */				      \
+0:	.asciz vendor;		/* vendor name */			      \
+1:	.balign 4;							      \
+2:
+
+#define ASM_ELF_NOTE_END						      \
+3:	.balign 4;		/* pad out section */			      \
+	.previous
+
+	ASM_ELF_NOTE_BEGIN(".note.kernel-version", "a", UTS_SYSNAME, 0)
+	.long LINUX_VERSION_CODE
+	ASM_ELF_NOTE_END
diff --git a/arch/powerpc/kernel/vdso32/sigtramp.S b/arch/powerpc/kernel/vdso32/sigtramp.S
new file mode 100644
index 00000000000..e0464278191
--- /dev/null
+++ b/arch/powerpc/kernel/vdso32/sigtramp.S
@@ -0,0 +1,300 @@
+/*
+ * Signal trampolines for 32 bits processes in a ppc64 kernel for
+ * use in the vDSO
+ *
+ * Copyright (C) 2004 Benjamin Herrenschmuidt (benh@kernel.crashing.org), IBM Corp.
+ * Copyright (C) 2004 Alan Modra (amodra@au.ibm.com)), 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/unistd.h>
+#include <asm/vdso.h>
+
+	.text
+
+/* The nop here is a hack.  The dwarf2 unwind routines subtract 1 from
+   the return address to get an address in the middle of the presumed
+   call instruction.  Since we don't have a call here, we artifically
+   extend the range covered by the unwind info by adding a nop before
+   the real start.  */
+	nop
+V_FUNCTION_BEGIN(__kernel_sigtramp32)
+.Lsig_start = . - 4
+	li	r0,__NR_sigreturn
+	sc
+.Lsig_end:
+V_FUNCTION_END(__kernel_sigtramp32)
+
+.Lsigrt_start:
+	nop
+V_FUNCTION_BEGIN(__kernel_sigtramp_rt32)
+	li	r0,__NR_rt_sigreturn
+	sc
+.Lsigrt_end:
+V_FUNCTION_END(__kernel_sigtramp_rt32)
+
+	.section .eh_frame,"a",@progbits
+
+/* Register r1 can be found at offset 4 of a pt_regs structure.
+   A pointer to the pt_regs is stored in memory at the old sp plus PTREGS.  */
+#define cfa_save \
+  .byte 0x0f;			/* DW_CFA_def_cfa_expression */		\
+  .uleb128 9f - 1f;		/*   length */				\
+1:									\
+  .byte 0x71; .sleb128 PTREGS;	/*     DW_OP_breg1 */			\
+  .byte 0x06;			/*     DW_OP_deref */			\
+  .byte 0x23; .uleb128 RSIZE;	/*     DW_OP_plus_uconst */		\
+  .byte 0x06;			/*     DW_OP_deref */			\
+9:
+
+/* Register REGNO can be found at offset OFS of a pt_regs structure.
+   A pointer to the pt_regs is stored in memory at the old sp plus PTREGS.  */
+#define rsave(regno, ofs) \
+  .byte 0x10;			/* DW_CFA_expression */			\
+  .uleb128 regno;		/*   regno */				\
+  .uleb128 9f - 1f;		/*   length */				\
+1:									\
+  .byte 0x71; .sleb128 PTREGS;	/*     DW_OP_breg1 */			\
+  .byte 0x06;			/*     DW_OP_deref */			\
+  .ifne ofs;								\
+    .byte 0x23; .uleb128 ofs;	/*     DW_OP_plus_uconst */		\
+  .endif;								\
+9:
+
+/* If msr bit 1<<25 is set, then VMX register REGNO is at offset REGNO*16
+   of the VMX reg struct.  The VMX reg struct is at offset VREGS of
+   the pt_regs struct.  This macro is for REGNO == 0, and contains
+   'subroutines' that the other macros jump to.  */
+#define vsave_msr0(regno) \
+  .byte 0x10;			/* DW_CFA_expression */			\
+  .uleb128 regno + 77;		/*   regno */				\
+  .uleb128 9f - 1f;		/*   length */				\
+1:									\
+  .byte 0x30 + regno;		/*     DW_OP_lit0 */			\
+2:									\
+  .byte 0x40;			/*     DW_OP_lit16 */			\
+  .byte 0x1e;			/*     DW_OP_mul */			\
+3:									\
+  .byte 0x71; .sleb128 PTREGS;	/*     DW_OP_breg1 */			\
+  .byte 0x06;			/*     DW_OP_deref */			\
+  .byte 0x12;			/*     DW_OP_dup */			\
+  .byte 0x23;			/*     DW_OP_plus_uconst */		\
+    .uleb128 33*RSIZE;		/*       msr offset */			\
+  .byte 0x06;			/*     DW_OP_deref */			\
+  .byte 0x0c; .long 1 << 25;	/*     DW_OP_const4u */			\
+  .byte 0x1a;			/*     DW_OP_and */			\
+  .byte 0x12;			/*     DW_OP_dup, ret 0 if bra taken */	\
+  .byte 0x30;			/*     DW_OP_lit0 */			\
+  .byte 0x29;			/*     DW_OP_eq */			\
+  .byte 0x28; .short 0x7fff;	/*     DW_OP_bra to end */		\
+  .byte 0x13;			/*     DW_OP_drop, pop the 0 */		\
+  .byte 0x23; .uleb128 VREGS;	/*     DW_OP_plus_uconst */		\
+  .byte 0x22;			/*     DW_OP_plus */			\
+  .byte 0x2f; .short 0x7fff;	/*     DW_OP_skip to end */		\
+9:
+
+/* If msr bit 1<<25 is set, then VMX register REGNO is at offset REGNO*16
+   of the VMX reg struct.  REGNO is 1 thru 31.  */
+#define vsave_msr1(regno) \
+  .byte 0x10;			/* DW_CFA_expression */			\
+  .uleb128 regno + 77;		/*   regno */				\
+  .uleb128 9f - 1f;		/*   length */				\
+1:									\
+  .byte 0x30 + regno;		/*     DW_OP_lit n */			\
+  .byte 0x2f; .short 2b - 9f;	/*     DW_OP_skip */			\
+9:
+
+/* If msr bit 1<<25 is set, then VMX register REGNO is at offset OFS of
+   the VMX save block.  */
+#define vsave_msr2(regno, ofs) \
+  .byte 0x10;			/* DW_CFA_expression */			\
+  .uleb128 regno + 77;		/*   regno */				\
+  .uleb128 9f - 1f;		/*   length */				\
+1:									\
+  .byte 0x0a; .short ofs;	/*     DW_OP_const2u */			\
+  .byte 0x2f; .short 3b - 9f;	/*     DW_OP_skip */			\
+9:
+
+/* VMX register REGNO is at offset OFS of the VMX save area.  */
+#define vsave(regno, ofs) \
+  .byte 0x10;			/* DW_CFA_expression */			\
+  .uleb128 regno + 77;		/*   regno */				\
+  .uleb128 9f - 1f;		/*   length */				\
+1:									\
+  .byte 0x71; .sleb128 PTREGS;	/*     DW_OP_breg1 */			\
+  .byte 0x06;			/*     DW_OP_deref */			\
+  .byte 0x23; .uleb128 VREGS;	/*     DW_OP_plus_uconst */		\
+  .byte 0x23; .uleb128 ofs;	/*     DW_OP_plus_uconst */		\
+9:
+
+/* This is where the pt_regs pointer can be found on the stack.  */
+#define PTREGS 64+28
+
+/* Size of regs.  */
+#define RSIZE 4
+
+/* This is the offset of the VMX regs.  */
+#define VREGS 48*RSIZE+34*8
+
+/* Describe where general purpose regs are saved.  */
+#define EH_FRAME_GEN \
+  cfa_save;								\
+  rsave ( 0,  0*RSIZE);							\
+  rsave ( 2,  2*RSIZE);							\
+  rsave ( 3,  3*RSIZE);							\
+  rsave ( 4,  4*RSIZE);							\
+  rsave ( 5,  5*RSIZE);							\
+  rsave ( 6,  6*RSIZE);							\
+  rsave ( 7,  7*RSIZE);							\
+  rsave ( 8,  8*RSIZE);							\
+  rsave ( 9,  9*RSIZE);							\
+  rsave (10, 10*RSIZE);							\
+  rsave (11, 11*RSIZE);							\
+  rsave (12, 12*RSIZE);							\
+  rsave (13, 13*RSIZE);							\
+  rsave (14, 14*RSIZE);							\
+  rsave (15, 15*RSIZE);							\
+  rsave (16, 16*RSIZE);							\
+  rsave (17, 17*RSIZE);							\
+  rsave (18, 18*RSIZE);							\
+  rsave (19, 19*RSIZE);							\
+  rsave (20, 20*RSIZE);							\
+  rsave (21, 21*RSIZE);							\
+  rsave (22, 22*RSIZE);							\
+  rsave (23, 23*RSIZE);							\
+  rsave (24, 24*RSIZE);							\
+  rsave (25, 25*RSIZE);							\
+  rsave (26, 26*RSIZE);							\
+  rsave (27, 27*RSIZE);							\
+  rsave (28, 28*RSIZE);							\
+  rsave (29, 29*RSIZE);							\
+  rsave (30, 30*RSIZE);							\
+  rsave (31, 31*RSIZE);							\
+  rsave (67, 32*RSIZE);		/* ap, used as temp for nip */		\
+  rsave (65, 36*RSIZE);		/* lr */				\
+  rsave (70, 38*RSIZE)		/* cr */
+
+/* Describe where the FP regs are saved.  */
+#define EH_FRAME_FP \
+  rsave (32, 48*RSIZE +  0*8);						\
+  rsave (33, 48*RSIZE +  1*8);						\
+  rsave (34, 48*RSIZE +  2*8);						\
+  rsave (35, 48*RSIZE +  3*8);						\
+  rsave (36, 48*RSIZE +  4*8);						\
+  rsave (37, 48*RSIZE +  5*8);						\
+  rsave (38, 48*RSIZE +  6*8);						\
+  rsave (39, 48*RSIZE +  7*8);						\
+  rsave (40, 48*RSIZE +  8*8);						\
+  rsave (41, 48*RSIZE +  9*8);						\
+  rsave (42, 48*RSIZE + 10*8);						\
+  rsave (43, 48*RSIZE + 11*8);						\
+  rsave (44, 48*RSIZE + 12*8);						\
+  rsave (45, 48*RSIZE + 13*8);						\
+  rsave (46, 48*RSIZE + 14*8);						\
+  rsave (47, 48*RSIZE + 15*8);						\
+  rsave (48, 48*RSIZE + 16*8);						\
+  rsave (49, 48*RSIZE + 17*8);						\
+  rsave (50, 48*RSIZE + 18*8);						\
+  rsave (51, 48*RSIZE + 19*8);						\
+  rsave (52, 48*RSIZE + 20*8);						\
+  rsave (53, 48*RSIZE + 21*8);						\
+  rsave (54, 48*RSIZE + 22*8);						\
+  rsave (55, 48*RSIZE + 23*8);						\
+  rsave (56, 48*RSIZE + 24*8);						\
+  rsave (57, 48*RSIZE + 25*8);						\
+  rsave (58, 48*RSIZE + 26*8);						\
+  rsave (59, 48*RSIZE + 27*8);						\
+  rsave (60, 48*RSIZE + 28*8);						\
+  rsave (61, 48*RSIZE + 29*8);						\
+  rsave (62, 48*RSIZE + 30*8);						\
+  rsave (63, 48*RSIZE + 31*8)
+
+/* Describe where the VMX regs are saved.  */
+#ifdef CONFIG_ALTIVEC
+#define EH_FRAME_VMX \
+  vsave_msr0 ( 0);							\
+  vsave_msr1 ( 1);							\
+  vsave_msr1 ( 2);							\
+  vsave_msr1 ( 3);							\
+  vsave_msr1 ( 4);							\
+  vsave_msr1 ( 5);							\
+  vsave_msr1 ( 6);							\
+  vsave_msr1 ( 7);							\
+  vsave_msr1 ( 8);							\
+  vsave_msr1 ( 9);							\
+  vsave_msr1 (10);							\
+  vsave_msr1 (11);							\
+  vsave_msr1 (12);							\
+  vsave_msr1 (13);							\
+  vsave_msr1 (14);							\
+  vsave_msr1 (15);							\
+  vsave_msr1 (16);							\
+  vsave_msr1 (17);							\
+  vsave_msr1 (18);							\
+  vsave_msr1 (19);							\
+  vsave_msr1 (20);							\
+  vsave_msr1 (21);							\
+  vsave_msr1 (22);							\
+  vsave_msr1 (23);							\
+  vsave_msr1 (24);							\
+  vsave_msr1 (25);							\
+  vsave_msr1 (26);							\
+  vsave_msr1 (27);							\
+  vsave_msr1 (28);							\
+  vsave_msr1 (29);							\
+  vsave_msr1 (30);							\
+  vsave_msr1 (31);							\
+  vsave_msr2 (33, 32*16+12);						\
+  vsave      (32, 32*16)
+#else
+#define EH_FRAME_VMX
+#endif
+
+.Lcie:
+	.long .Lcie_end - .Lcie_start
+.Lcie_start:
+	.long 0			/* CIE ID */
+	.byte 1			/* Version number */
+	.string "zR"		/* NUL-terminated augmentation string */
+	.uleb128 4		/* Code alignment factor */
+	.sleb128 -4		/* Data alignment factor */
+	.byte 67		/* Return address register column, ap */
+	.uleb128 1		/* Augmentation value length */
+	.byte 0x1b		/* DW_EH_PE_pcrel | DW_EH_PE_sdata4. */
+	.byte 0x0c,1,0		/* DW_CFA_def_cfa: r1 ofs 0 */
+	.balign 4
+.Lcie_end:
+
+	.long .Lfde0_end - .Lfde0_start
+.Lfde0_start:
+	.long .Lfde0_start - .Lcie	/* CIE pointer. */
+	.long .Lsig_start - .		/* PC start, length */
+	.long .Lsig_end - .Lsig_start
+	.uleb128 0			/* Augmentation */
+	EH_FRAME_GEN
+	EH_FRAME_FP
+	EH_FRAME_VMX
+	.balign 4
+.Lfde0_end:
+
+/* We have a different stack layout for rt_sigreturn.  */
+#undef PTREGS
+#define PTREGS 64+16+128+20+28
+
+	.long .Lfde1_end - .Lfde1_start
+.Lfde1_start:
+	.long .Lfde1_start - .Lcie	/* CIE pointer. */
+	.long .Lsigrt_start - .		/* PC start, length */
+	.long .Lsigrt_end - .Lsigrt_start
+	.uleb128 0			/* Augmentation */
+	EH_FRAME_GEN
+	EH_FRAME_FP
+	EH_FRAME_VMX
+	.balign 4
+.Lfde1_end:
diff --git a/arch/powerpc/kernel/vdso32/vdso32.lds.S b/arch/powerpc/kernel/vdso32/vdso32.lds.S
new file mode 100644
index 00000000000..f4bad720cb0
--- /dev/null
+++ b/arch/powerpc/kernel/vdso32/vdso32.lds.S
@@ -0,0 +1,117 @@
+
+/*
+ * This is the infamous ld script for the 32 bits vdso
+ * library
+ */
+#include <asm/vdso.h>
+
+/* Default link addresses for the vDSOs */
+OUTPUT_FORMAT("elf32-powerpc", "elf32-powerpc", "elf32-powerpc")
+OUTPUT_ARCH(powerpc:common)
+ENTRY(_start)
+
+SECTIONS
+{
+  . = VDSO32_LBASE + SIZEOF_HEADERS;
+  .hash           : { *(.hash) }			:text
+  .dynsym         : { *(.dynsym) }
+  .dynstr         : { *(.dynstr) }
+  .gnu.version    : { *(.gnu.version) }
+  .gnu.version_d  : { *(.gnu.version_d) }
+  .gnu.version_r  : { *(.gnu.version_r) }
+
+  .note		  : { *(.note.*) } 			:text	:note
+
+  . = ALIGN (16);
+  .text :
+  {
+    *(.text .stub .text.* .gnu.linkonce.t.*)
+  }
+  PROVIDE (__etext = .);
+  PROVIDE (_etext = .);
+  PROVIDE (etext = .);
+
+  /* Other stuff is appended to the text segment: */
+  .rodata		: { *(.rodata .rodata.* .gnu.linkonce.r.*) }
+  .rodata1		: { *(.rodata1) }
+
+  .eh_frame_hdr		: { *(.eh_frame_hdr) }		:text	:eh_frame_hdr
+  .eh_frame		: { KEEP (*(.eh_frame)) }	:text
+  .gcc_except_table	: { *(.gcc_except_table) }
+  .fixup		: { *(.fixup) }
+
+  .dynamic		: { *(.dynamic) }		:text	:dynamic
+  .got : { *(.got) }
+  .plt : { *(.plt) }
+
+  _end = .;
+  __end = .;
+  PROVIDE (end = .);
+
+
+  /* Stabs debugging sections are here too
+   */
+  .stab 0 : { *(.stab) }
+  .stabstr 0 : { *(.stabstr) }
+  .stab.excl 0 : { *(.stab.excl) }
+  .stab.exclstr 0 : { *(.stab.exclstr) }
+  .stab.index 0 : { *(.stab.index) }
+  .stab.indexstr 0 : { *(.stab.indexstr) }
+  .comment 0 : { *(.comment) }
+  .debug 0 : { *(.debug) }
+  .line 0 : { *(.line) }
+
+  .debug_srcinfo 0 : { *(.debug_srcinfo) }
+  .debug_sfnames 0 : { *(.debug_sfnames) }
+
+  .debug_aranges 0 : { *(.debug_aranges) }
+  .debug_pubnames 0 : { *(.debug_pubnames) }
+
+  .debug_info 0 : { *(.debug_info .gnu.linkonce.wi.*) }
+  .debug_abbrev 0 : { *(.debug_abbrev) }
+  .debug_line 0 : { *(.debug_line) }
+  .debug_frame 0 : { *(.debug_frame) }
+  .debug_str 0 : { *(.debug_str) }
+  .debug_loc 0 : { *(.debug_loc) }
+  .debug_macinfo 0 : { *(.debug_macinfo) }
+
+  .debug_weaknames 0 : { *(.debug_weaknames) }
+  .debug_funcnames 0 : { *(.debug_funcnames) }
+  .debug_typenames 0 : { *(.debug_typenames) }
+  .debug_varnames 0 : { *(.debug_varnames) }
+
+  /DISCARD/ : { *(.note.GNU-stack) }
+  /DISCARD/ : { *(.data .data.* .gnu.linkonce.d.* .sdata*) }
+  /DISCARD/ : { *(.bss .sbss .dynbss .dynsbss) }
+}
+
+
+PHDRS
+{
+  text PT_LOAD FILEHDR PHDRS FLAGS(5); /* PF_R|PF_X */
+  note PT_NOTE FLAGS(4); /* PF_R */
+  dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
+  eh_frame_hdr 0x6474e550; /* PT_GNU_EH_FRAME, but ld doesn't match the name */
+}
+
+
+/*
+ * This controls what symbols we export from the DSO.
+ */
+VERSION
+{
+  VDSO_VERSION_STRING {
+    global:
+	__kernel_datapage_offset; /* Has to be there for the kernel to find */
+	__kernel_get_syscall_map;
+	__kernel_gettimeofday;
+	__kernel_clock_gettime;
+	__kernel_clock_getres;
+	__kernel_get_tbfreq;
+	__kernel_sync_dicache;
+	__kernel_sync_dicache_p5;
+	__kernel_sigtramp32;
+	__kernel_sigtramp_rt32;
+    local: *;
+  };
+}
diff --git a/arch/powerpc/kernel/vdso32/vdso32_wrapper.S b/arch/powerpc/kernel/vdso32/vdso32_wrapper.S
new file mode 100644
index 00000000000..556f0caa5d8
--- /dev/null
+++ b/arch/powerpc/kernel/vdso32/vdso32_wrapper.S
@@ -0,0 +1,13 @@
+#include <linux/init.h>
+#include <asm/page.h>
+
+	.section ".data.page_aligned"
+
+	.globl vdso32_start, vdso32_end
+	.balign PAGE_SIZE
+vdso32_start:
+	.incbin "arch/powerpc/kernel/vdso32/vdso32.so"
+	.balign PAGE_SIZE
+vdso32_end:
+
+	.previous