[PATCH 0/3] kvm-userspace: ppc: userspace fixes for powerpc

[PATCH 0/3] kvm-userspace: ppc: userspace fixes for powerpc

[ehrhardt-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8]

From: Christian Ehrhardt <ehrhardt-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>

This is a set of fixes for the powerpc tests kvm-userspace/user.

Patch 1&2 fix main-ppc.c while patch 3 introduces libcflat for powerpc.
Further on patch 4 provides a timebase accessor for the ppc testcases (not
used yet) and patch 5 finally adds a stub nmi handler to main-ppc.c.

[patches in series]
[PATCH 1/5] user: ppc: fix threading bugs in main-ppc.c
[PATCH 2/5] user: ppc: better error reporting in load_file
[PATCH 3/5] user: ppc: implement PowerPC 44x libcflat
[PATCH 4/5] libcflat: ppc: add timebase accessor
[PATCH 5/5] user: ppc: add stub nmi handler

---
[diffstat]
 b/user/config-powerpc-44x.mak          |   14 +++++++++
 b/user/config-powerpc.mak              |   46 ++++++++++++++++++++---------
 b/user/main-ppc.c                      |   32 +++++++-------------
 b/user/test/lib/powerpc/44x/map.c      |   51 +++++++++++++++++++++++++++++++++
 b/user/test/lib/powerpc/44x/timebase.S |   28 ++++++++++++++++++
 b/user/test/lib/powerpc/44x/timebase.h |   25 ++++++++++++++++
 b/user/test/lib/powerpc/44x/tlbwe.S    |   29 ++++++++++++++++++
 b/user/test/lib/powerpc/io.c           |   35 ++++++++++++++++++++++
 b/user/test/powerpc/cstart.S           |   38 ++++++++++++++++++++++++
 b/user/test/powerpc/exit.c             |   23 ++++++++++++++
 user/config-powerpc-44x.mak            |    3 +
 user/main-ppc.c                        |    9 +++++
 12 files changed, 296 insertions(+), 37 deletions(-)
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[PATCH 1/5] user: ppc: fix threading bugs in main-ppc.c

[ehrhardt]

From: Hollis Blanchard <hollisb@us.ibm.com>

- call io_table_register() before any vcpus have started
- wait for all vcpus to exit before exiting the parent thread

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
---

[diffstat]
 main-ppc.c |   32 ++++++++++++--------------------
 1 file changed, 12 insertions(+), 20 deletions(-)

[diff]
diff --git a/user/main-ppc.c b/user/main-ppc.c
--- a/user/main-ppc.c
+++ b/user/main-ppc.c
@@ -51,7 +51,7 @@ struct io_table mmio_table;
 struct io_table mmio_table;
 
 static int ncpus = 1;
-static sem_t init_sem;
+static sem_t exited_sem;
 static __thread int vcpu;
 static sigset_t kernel_sigmask;
 static sigset_t ipi_sigmask;
@@ -220,16 +220,8 @@ void sync_caches(void *mem, unsigned lon
 	asm volatile ("sync; isync");
 }
 
-static void init_vcpu(int n, unsigned long entry)
+static void init_vcpu(int n)
 {
-	/* XXX must set initial TLB state and stack
-	struct kvm_regs regs = {
-		.pc = entry,
-	};
-
-	kvm_set_regs(kvm, 0, &regs);
-	*/
-
 	sigemptyset(&ipi_sigmask);
 	sigaddset(&ipi_sigmask, IPI_SIGNAL);
 	sigprocmask(SIG_UNBLOCK, &ipi_sigmask, NULL);
@@ -237,7 +229,6 @@ static void init_vcpu(int n, unsigned lo
 	vcpus[n].tid = gettid();
 	vcpu = n;
 	kvm_set_signal_mask(kvm, n, &kernel_sigmask);
-	sem_post(&init_sem);
 }
 
 static void *do_create_vcpu(void *_n)
@@ -245,8 +236,9 @@ static void *do_create_vcpu(void *_n)
 	int n = (long)_n;
 
 	kvm_create_vcpu(kvm, n);
-	init_vcpu(n, 0x0);
+	init_vcpu(n);
 	kvm_run(kvm, n);
+	sem_post(&exited_sem);
 	return NULL;
 }
 
@@ -368,14 +360,14 @@ int main(int argc, char **argv)
 	len = load_file(vm_mem, argv[optind], 1);
 	sync_caches(vm_mem, len);
 
-	sem_init(&init_sem, 0, 0);
-	init_vcpu(0, 0x0);
-	for (i = 1; i < ncpus; ++i)
-		start_vcpu(i);
-	for (i = 0; i < ncpus; ++i)
-		sem_wait(&init_sem);
-
 	io_table_register(&mmio_table, 0xf0000000, 64, mmio_handler, NULL);
 
-	return kvm_run(kvm, 0);
+	sem_init(&exited_sem, 0, 0);
+	for (i = 0; i < ncpus; ++i)
+		start_vcpu(i);
+	/* Wait for all vcpus to exit. */
+	for (i = 0; i < ncpus; ++i)
+		sem_wait(&exited_sem);
+
+	return 0;
 }

[PATCH 2/5] user: ppc: better error reporting in load_file

[ehrhardt]

From: Hollis Blanchard <hollisb@us.ibm.com>

Fancy description.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
---

[diffstat]
 main-ppc.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

[diff]
diff --git a/user/main-ppc.c b/user/main-ppc.c
--- a/user/main-ppc.c
+++ b/user/main-ppc.c
@@ -183,7 +183,7 @@ static struct kvm_callbacks test_callbac
 
 static unsigned long load_file(void *mem, const char *fname, int inval_icache)
 {
-	int r;
+	ssize_t r;
 	int fd;
 	unsigned long bytes = 0;
 
@@ -200,6 +200,7 @@ static unsigned long load_file(void *mem
 
 	if (r == -1) {
 		perror("read");
+		printf("read %d bytes\n", bytes);
 		exit(1);
 	}
 

[PATCH 3/5] user: ppc: implement PowerPC 44x libcflat

[ehrhardt-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8]

From: Hollis Blanchard <hollisb-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>

- Create a 44x-specific makefile.
- Reorganize PowerPC makefiles to separate "simple" tests from those which
  link with libcflat.
- Create a minimal libcflat testcase (which just exits).

Signed-off-by: Hollis Blanchard <hollisb-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
Signed-off-by: Christian Ehrhardt <ehrhardt-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
---

[diffstat]
 config-powerpc-44x.mak       |   14 +++++++++++
 config-powerpc.mak           |   46 ++++++++++++++++++++++++++------------
 test/lib/powerpc/44x/map.c   |   51 +++++++++++++++++++++++++++++++++++++++++++
 test/lib/powerpc/44x/tlbwe.S |   29 ++++++++++++++++++++++++
 test/lib/powerpc/io.c        |   35 +++++++++++++++++++++++++++++
 test/powerpc/cstart.S        |   38 ++++++++++++++++++++++++++++++++
 test/powerpc/exit.c          |   23 +++++++++++++++++++
 7 files changed, 221 insertions(+), 15 deletions(-)

[diff]

diff --git a/user/config-powerpc-44x.mak b/user/config-powerpc-44x.mak
new file mode 100644
--- /dev/null
+++ b/user/config-powerpc-44x.mak
@@ -0,0 +1,14 @@
+
+
+# for some reason binutils hates tlbsx unless we say we're 405  :(
+CFLAGS += -Wa,-m405 -I test/lib/powerpc/44x
+
+cflatobjs += \
+	test/lib/powerpc/44x/map.o \
+	test/lib/powerpc/44x/tlbwe.o
+
+simpletests += \
+	test/powerpc/44x/tlbsx.bin \
+	test/powerpc/44x/tlbwe_16KB.bin \
+	test/powerpc/44x/tlbwe_hole.bin \
+	test/powerpc/44x/tlbwe.bin
diff --git a/user/config-powerpc.mak b/user/config-powerpc.mak
--- a/user/config-powerpc.mak
+++ b/user/config-powerpc.mak
@@ -1,26 +1,42 @@
+platform := 44x
+
 CFLAGS += -m32
 CFLAGS += -D__powerpc__
 CFLAGS += -I $(KERNELDIR)/include
-# for some reaons binutils hates tlbsx unless we say we're 405  :(
-CFLAGS += -Wa,-mregnames,-m405
+CFLAGS += -Wa,-mregnames -I test/lib
 
-%.bin: %.o
-	$(OBJCOPY) -O binary $^ $@
+cstart := test/powerpc/cstart.o
 
-testobjs := \
-	io.bin \
-	spin.bin \
-	sprg.bin \
-	44x/tlbsx.bin \
-	44x/tlbwe_16KB.bin \
-	44x/tlbwe_hole.bin \
-	44x/tlbwe.bin
+cflatobjs += \
+	test/lib/powerpc/io.o
 
-tests := $(addprefix test/powerpc/, $(testobjs))
+$(libcflat): LDFLAGS += -nostdlib
+$(libcflat): CFLAGS += -ffreestanding
 
-all: kvmtrace kvmctl $(tests)
+# these tests do not use libcflat
+simpletests := \
+	test/powerpc/spin.bin \
+	test/powerpc/io.bin \
+	test/powerpc/sprg.bin
+
+# theses tests use cstart.o, libcflat, and libgcc
+tests := \
+	test/powerpc/exit.bin
+
+include config-powerpc-$(platform).mak
+
+
+all: kvmtrace kvmctl $(libcflat) $(simpletests) $(tests)
+
+$(simpletests): %.bin: %.o
+	$(CC) -nostdlib $^ -Wl,-T,flat.lds -o $@
+
+$(tests): %.bin: $(cstart) %.o $(libcflat)
+	$(CC) -nostdlib $^ $(libgcc) -Wl,-T,flat.lds -o $@
 
 kvmctl_objs = main-ppc.o iotable.o ../libkvm/libkvm.a
 
 arch_clean:
-	rm -f $(tests)
+	$(RM) $(simpletests) $(tests) $(cstart)
+	$(RM) $(patsubst %.bin, %.elf, $(simpletests) $(tests))
+	$(RM) $(patsubst %.bin, %.o, $(simpletests) $(tests))
diff --git a/user/test/lib/powerpc/44x/map.c b/user/test/lib/powerpc/44x/map.c
new file mode 100644
--- /dev/null
+++ b/user/test/lib/powerpc/44x/map.c
@@ -0,0 +1,51 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright IBM Corp. 2008
+ *
+ * Authors: Hollis Blanchard <hollisb-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
+ */
+
+#include "libcflat.h"
+
+#define TLB_SIZE 64
+
+extern void tlbwe(unsigned int index,
+		  unsigned char tid,
+		  unsigned int word0,
+		  unsigned int word1,
+		  unsigned int word2);
+
+unsigned int next_free_index;
+
+#define PAGE_SHIFT 12
+#define PAGE_MASK (~((1<<PAGE_SHIFT)-1))
+
+#define V (1<<9)
+
+void map(unsigned long vaddr, unsigned long paddr)
+{
+	unsigned int w0, w1, w2;
+
+	/* We don't install exception handlers, so we can't handle TLB misses,
+	 * so we can't loop around and overwrite entry 0. */
+	if (next_free_index++ >= TLB_SIZE)
+		panic("TLB overflow");
+
+	w0 = (vaddr & PAGE_MASK) | V;
+	w1 = paddr & PAGE_MASK;
+	w2 = 0x3;
+
+	tlbwe(next_free_index, 0, w0, w1, w2);
+}
diff --git a/user/test/lib/powerpc/44x/tlbwe.S b/user/test/lib/powerpc/44x/tlbwe.S
new file mode 100644
--- /dev/null
+++ b/user/test/lib/powerpc/44x/tlbwe.S
@@ -0,0 +1,29 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright IBM Corp. 2008
+ *
+ * Authors: Hollis Blanchard <hollisb-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
+ */
+
+#define SPRN_MMUCR 0x3b2
+
+/* tlbwe(uint index, uint8_t tid, uint word0, uint word1, uint word2) */
+.global tlbwe
+tlbwe:
+	mtspr	SPRN_MMUCR, r4
+	tlbwe	r5, r3, 0
+	tlbwe	r6, r3, 1
+	tlbwe	r7, r3, 2
+	blr
diff --git a/user/test/lib/powerpc/io.c b/user/test/lib/powerpc/io.c
new file mode 100644
--- /dev/null
+++ b/user/test/lib/powerpc/io.c
@@ -0,0 +1,35 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright IBM Corp. 2008
+ *
+ * Authors: Hollis Blanchard <hollisb-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
+ */
+
+#include "libcflat.h"
+
+#define BASE 0xf0000000
+#define _putc ((volatile char *)(BASE))
+#define _exit ((volatile char *)(BASE+1))
+
+void puts(const char *s)
+{
+	while (*s != '\0')
+		*_putc = *s++;
+}
+
+void exit(int code)
+{
+	*_exit = code;
+}
diff --git a/user/test/powerpc/cstart.S b/user/test/powerpc/cstart.S
new file mode 100644
--- /dev/null
+++ b/user/test/powerpc/cstart.S
@@ -0,0 +1,38 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright IBM Corp. 2008
+ *
+ * Authors: Hollis Blanchard <hollisb-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
+ */
+
+#define OUTPUT_VADDR 0xf0000000
+#define OUTPUT_PADDR 0xf0000000
+
+.globl _start
+_start:
+	/* In the future we might need to assign a stack and zero BSS here. */
+
+	/* Map the debug page 1:1. */
+	lis	r3, OUTPUT_VADDR@h
+	ori	r3, r3, OUTPUT_VADDR@l
+	lis	r4, OUTPUT_PADDR@h
+	ori	r4, r4, OUTPUT_PADDR@l
+	bl	map
+
+	/* Call main() and pass return code to exit(). */
+	bl	main
+	bl	exit
+
+	b	.
diff --git a/user/test/powerpc/exit.c b/user/test/powerpc/exit.c
new file mode 100644
--- /dev/null
+++ b/user/test/powerpc/exit.c
@@ -0,0 +1,23 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright IBM Corp. 2008
+ *
+ * Authors: Hollis Blanchard <hollisb-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
+ */
+
+int main(void)
+{
+	return 1;
+}
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[PATCH 5/5] user: ppc: add stub nmi handler

[ehrhardt-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8]

From: Hollis Blanchard <hollisb-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>

Adding a nmi stub handler for user/main-ppc.c. We already pushed a stub
for qemu but not for the test suite in the user dir.

Signed-off-by: Hollis Blanchard <hollisb-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
Signed-off-by: Christian Ehrhardt <ehrhardt-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
---

[diffstat]
 main-ppc.c |    6 ++++++
 1 file changed, 6 insertions(+)

[diff]
diff --git a/user/main-ppc.c b/user/main-ppc.c
--- a/user/main-ppc.c
+++ b/user/main-ppc.c
@@ -83,6 +83,11 @@ static int test_io_window(void *opaque)
 }
 
 static int test_try_push_interrupts(void *opaque)
+{
+	return 0;
+}
+
+static int test_try_push_nmi(void *opaque)
 {
 	return 0;
 }
@@ -175,6 +180,7 @@ static struct kvm_callbacks test_callbac
 	.halt        = test_halt,
 	.io_window = test_io_window,
 	.try_push_interrupts = test_try_push_interrupts,
+	.try_push_nmi = test_try_push_nmi,
 	.post_kvm_run = test_post_kvm_run,
 	.pre_kvm_run = test_pre_kvm_run,
 	.powerpc_dcr_read = test_dcr_read,
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Re: [PATCH 0/3] kvm-userspace: ppc: userspace fixes for powerpc

[Christian Ehrhardt]

Ok I should have send these two series with some minutes in between to 
not intermix them :-/
Additionally I have the wrong header in this one it should be [0/5] :-/++

Overall it is a patch series of three patches for powerpc kvm-userspace, 
a five patch series for kvm-suerspace/user/ and a single patch I just 
submitted while cleaning our userspace repo to get the missing things 
upstream.

Avi, let me know if I confused you and I'll send them once again with 
some time in between to order them easier.

ehrhardt-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org wrote:
> From: Christian Ehrhardt <ehrhardt-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
>
> This is a set of fixes for the powerpc tests kvm-userspace/user.
>
> Patch 1&2 fix main-ppc.c while patch 3 introduces libcflat for powerpc.
> Further on patch 4 provides a timebase accessor for the ppc testcases (not
> used yet) and patch 5 finally adds a stub nmi handler to main-ppc.c.
>
> [patches in series]
> [PATCH 1/5] user: ppc: fix threading bugs in main-ppc.c
> [PATCH 2/5] user: ppc: better error reporting in load_file
> [PATCH 3/5] user: ppc: implement PowerPC 44x libcflat
> [PATCH 4/5] libcflat: ppc: add timebase accessor
> [PATCH 5/5] user: ppc: add stub nmi handler
>
> ---
> [diffstat]
>  b/user/config-powerpc-44x.mak          |   14 +++++++++
>  b/user/config-powerpc.mak              |   46 ++++++++++++++++++++---------
>  b/user/main-ppc.c                      |   32 +++++++-------------
>  b/user/test/lib/powerpc/44x/map.c      |   51 +++++++++++++++++++++++++++++++++
>  b/user/test/lib/powerpc/44x/timebase.S |   28 ++++++++++++++++++
>  b/user/test/lib/powerpc/44x/timebase.h |   25 ++++++++++++++++
>  b/user/test/lib/powerpc/44x/tlbwe.S    |   29 ++++++++++++++++++
>  b/user/test/lib/powerpc/io.c           |   35 ++++++++++++++++++++++
>  b/user/test/powerpc/cstart.S           |   38 ++++++++++++++++++++++++
>  b/user/test/powerpc/exit.c             |   23 ++++++++++++++
>  user/config-powerpc-44x.mak            |    3 +
>  user/main-ppc.c                        |    9 +++++
>  12 files changed, 296 insertions(+), 37 deletions(-)
> --
> To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in
> the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>   


-- 

Grüsse / regards, 
Christian Ehrhardt
IBM Linux Technology Center, Open Virtualization

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[PATCH 4/5] libcflat: ppc: add timebase accessor

[ehrhardt]

Provide a timebase accessor for ppc testcases.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>

[diffstat]
 config-powerpc-44x.mak          |    3 ++-
 test/lib/powerpc/44x/timebase.S |   28 ++++++++++++++++++++++++++++
 test/lib/powerpc/44x/timebase.h |   25 +++++++++++++++++++++++++
 3 files changed, 55 insertions(+), 1 deletion(-)

[diff]
diff --git a/user/config-powerpc-44x.mak b/user/config-powerpc-44x.mak
--- a/user/config-powerpc-44x.mak
+++ b/user/config-powerpc-44x.mak
@@ -5,7 +5,8 @@
 
 cflatobjs += \
 	test/lib/powerpc/44x/map.o \
-	test/lib/powerpc/44x/tlbwe.o
+	test/lib/powerpc/44x/tlbwe.o \
+	test/lib/powerpc/44x/timebase.o
 
 simpletests += \
 	test/powerpc/44x/tlbsx.bin \
diff --git a/user/test/lib/powerpc/44x/timebase.S b/user/test/lib/powerpc/44x/timebase.S
new file mode 100644
--- /dev/null
+++ b/user/test/lib/powerpc/44x/timebase.S
@@ -0,0 +1,28 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright IBM Corp. 2008
+ *
+ * Authors: Hollis Blanchard <hollisb@us.ibm.com>
+ */
+
+/* unsigned long long mftb(void); */
+.global mftb
+mftb:
+	mftbu	r5
+	mftbl 	r4
+	mftbu 	r3
+	cmpw 	r3, r5
+	bne 	mftb
+	blr
diff --git a/user/test/lib/powerpc/44x/timebase.h b/user/test/lib/powerpc/44x/timebase.h
new file mode 100644
--- /dev/null
+++ b/user/test/lib/powerpc/44x/timebase.h
@@ -0,0 +1,25 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * Copyright IBM Corp. 2008
+ *
+ * Authors: Hollis Blanchard <hollisb@us.ibm.com>
+ */
+
+#ifndef __TIMEBASE_H__
+#define __TIMEBASE_H__
+
+unsigned long long mftb(void);
+
+#endif /* __TIMEBASE_H__ */