base: ASM sched func

Rewrite part of kernel in assembly language

This patch reimplement part of kernel in assembly language to
guarantee particular stack layout.

Signed-off-by: Kazunori Asayama <asayama@sm.sony.co.jp>
Signed-off-by: Yuji Mano <yuji.mano@am.sony.com>

7 files changed, 161 insertions, 53 deletions

diff --git a/base/src/common/kernel_internal_types.h b/base/src/common/kernel_internal_types.h
index eec536e..bf7b568 100644
--- a/base/src/common/kernel_internal_types.h
+++ b/base/src/common/kernel_internal_types.h
@@ -123,7 +123,4 @@ int dma_get(void *ls, uint64_t ea, uint32_t size, uint32_t tag);
 int dma_put(const void *ls, uint64_t ea, uint32_t size, uint32_t tag);
 int dma_wait(uint32_t tag);
 
-/* mars module entry */
-void mars_module_entry(struct mars_kernel_syscalls *syscalls);
-
 #endif
diff --git a/base/src/mpu/kernel/Makefile.am b/base/src/mpu/kernel/Makefile.am
index fde5540..3afc74a 100644
--- a/base/src/mpu/kernel/Makefile.am
+++ b/base/src/mpu/kernel/Makefile.am
@@ -98,6 +98,7 @@ mars_kernel_SOURCES = \
 	$(srcdir)/../../../src/common/*.h \
 	dma.c \
 	kernel.c \
-	mutex.c
+	mutex.c \
+	switch.S
 
 CLEANFILES = *.map
diff --git a/base/src/mpu/kernel/kernel.c b/base/src/mpu/kernel/kernel.c
index b37959c..b2de697 100644
--- a/base/src/mpu/kernel/kernel.c
+++ b/base/src/mpu/kernel/kernel.c
@@ -48,7 +48,6 @@
 #include "workload_internal_types.h"
 
 /* kernel */
-void *__kernel_stack;
 union mars_kernel_buffer kernel_buffer;
 static struct mars_kernel_params kernel_params;
 
@@ -75,6 +74,14 @@ static struct mars_workload_module cached_workload_module;
 typedef void (*module_entry)(
 	const struct mars_kernel_syscalls *kernel_syscalls);
 
+/* defined in switch.S */
+extern void workload_run(void);
+extern void workload_exit(uint8_t state);
+
+/* called by switch.S */
+void __workload_run(void);
+void __workload_exit(uint8_t state);
+
 static int kernel_memcmp(const void *s1, const void *s2, int size)
 {
 	__vector const int *vptr_1 = (__vector const int *)s1;
@@ -329,22 +336,6 @@ static int change_state(uint16_t id,
 		           callback);
 }
 
-
-static void __attribute__((noinline)) save_workload_state(uint8_t state)
-{
-	workload_state = state;
-}
-
-static void workload_exit(uint8_t state)
-{
-	register void *sp asm("$sp");
-
-	save_workload_state(state);
-
-	/* restore kernel stack pointer */
-	sp = __kernel_stack;
-}
-
 static int workload_query(uint16_t id, int query)
 {
 	uint64_t bits = get_block_bits(id);
@@ -545,6 +536,17 @@ static struct mars_kernel_syscalls kernel_syscalls =
 	dma_wait
 };
 
+void __workload_run(void)
+{
+	/* call module entry function */
+	((module_entry)workload_module->entry)(&kernel_syscalls);
+}
+
+void __workload_exit(uint8_t state)
+{
+	workload_state = state;
+}
+
 static int search_block(int block, int ready)
 {
 	int i;
@@ -773,17 +775,6 @@ static void workload_release(void)
 		notify_host_bits(block_ea, index);
 }
 
-static void __attribute__((noinline)) workload_run(void)
-{
-	register void *sp asm("$sp");
-
-	/* save kernel stack pointer */
-	__kernel_stack = sp;
-
-	/* call module entry function */
-	((module_entry)workload_module->entry)(&kernel_syscalls);
-}
-
 static void workload_module_load(void)
 {
 	__vector unsigned char *bss_ptr, *bss_end;
diff --git a/base/src/mpu/kernel/switch.S b/base/src/mpu/kernel/switch.S
new file mode 100644
index 0000000..7ddfede
--- /dev/null
+++ b/base/src/mpu/kernel/switch.S
@@ -0,0 +1,80 @@
+/*
+ * Copyright 2009 Sony Corporation of America
+ *
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this Library and associated documentation files (the
+ * "Library"), to deal in the Library without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Library, and to
+ * permit persons to whom the Library is furnished to do so, subject to
+ * the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be
+ *  included in all copies or substantial portions of the Library.
+ *
+ *  If you modify the Library, you may copy and distribute your modified
+ *  version of the Library in object code or as an executable provided
+ *  that you also do one of the following:
+ *
+ *   Accompany the modified version of the Library with the complete
+ *   corresponding machine-readable source code for the modified version
+ *   of the Library; or,
+ *
+ *   Accompany the modified version of the Library with a written offer
+ *   for a complete machine-readable copy of the corresponding source
+ *   code of the modified version of the Library.
+ *
+ *
+ * THE LIBRARY IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * LIBRARY OR THE USE OR OTHER DEALINGS IN THE LIBRARY.
+ */
+
+.data
+
+/* void *__kernel_stack */
+.align	4
+.globl	__kernel_stack
+__kernel_stack:
+.space	4
+
+
+.text
+
+/* void workload_run(void) */
+.global	workload_run
+.type	workload_run, @function
+workload_run:
+	stqd	$LR, 16($SP)			/* save link register */
+	stqd	$SP, -32($SP)			/* save back chain */
+	ai	$SP, $SP, -32			/* push stack frame */
+
+	stqr	$SP, __kernel_stack		/* save kernel stack pointer */
+	brsl	$LR, __workload_run		/* call body of workload_run */
+
+	ai	$SP, $SP, 32			/* pop stack frame */
+	lqd	$LR, 16($SP)			/* restore link register */
+	bi	$LR				/* return */
+.size	workload_run, .-workload_run
+
+
+/* void workload_exit(uint8_t state) */
+.global	workload_exit
+.type	workload_exit, @function
+workload_exit:
+	stqd	$LR, 16($SP)			/* save link register */
+	stqd	$SP, -32($SP)			/* save back chain */
+	ai	$SP, $SP, -32			/* push stack frame */
+
+	brsl	$LR, __workload_exit		/* call body of workload_exit */
+	lqr	$SP, __kernel_stack		/* restore kernel stack */
+
+	ai	$SP, $SP, 32			/* pop stack frame */
+	lqd	$LR, 16($SP)			/* restore link register */
+	bi	$LR				/* return */
+.size	workload_exit, .-workload_exit
diff --git a/base/src/mpu/lib/Makefile.am b/base/src/mpu/lib/Makefile.am
index 643b5ed..f306e1d 100644
--- a/base/src/mpu/lib/Makefile.am
+++ b/base/src/mpu/lib/Makefile.am
@@ -92,4 +92,5 @@ lib_LTLIBRARIES = libmars_base.la
 
 libmars_base_la_SOURCES = \
 	$(srcdir)/../../../src/common/*.h \
+	entry.S \
 	module.c
diff --git a/base/src/mpu/lib/entry.S b/base/src/mpu/lib/entry.S
new file mode 100644
index 0000000..353a55f
--- /dev/null
+++ b/base/src/mpu/lib/entry.S
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2009 Sony Corporation of America
+ *
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this Library and associated documentation files (the
+ * "Library"), to deal in the Library without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Library, and to
+ * permit persons to whom the Library is furnished to do so, subject to
+ * the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be
+ *  included in all copies or substantial portions of the Library.
+ *
+ *  If you modify the Library, you may copy and distribute your modified
+ *  version of the Library in object code or as an executable provided
+ *  that you also do one of the following:
+ *
+ *   Accompany the modified version of the Library with the complete
+ *   corresponding machine-readable source code for the modified version
+ *   of the Library; or,
+ *
+ *   Accompany the modified version of the Library with a written offer
+ *   for a complete machine-readable copy of the corresponding source
+ *   code of the modified version of the Library.
+ *
+ *
+ * THE LIBRARY IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * LIBRARY OR THE USE OR OTHER DEALINGS IN THE LIBRARY.
+ */
+
+.text
+
+/* void mars_module_entry(struct mars_kernel_syscalls *syscalls) */
+.global	mars_module_entry
+.type	mars_module_entry, @function
+mars_module_entry:
+	ila	$SP, __stack		/* switch to module stack */
+	il	$LR, 0			/* set module link register to NULL */
+	stqd	$LR, 0($SP)		/* initialize back chain to NULL */
+	stqd	$SP, -32($SP)		/* initialize stack frame */
+	ai	$SP, $SP, -32		/* push stack frame */
+	brsl	$LR, __module_entry	/* call module entry body */
+.size	mars_module_entry, .-mars_module_entry
diff --git a/base/src/mpu/lib/module.c b/base/src/mpu/lib/module.c
index af1ce15..8459f2b 100644
--- a/base/src/mpu/lib/module.c
+++ b/base/src/mpu/lib/module.c
@@ -42,32 +42,20 @@
 #include "kernel_internal_types.h"
 #include "workload_internal_types.h"
 
+/* global kernel syscalls pointer */
 static struct mars_kernel_syscalls *kernel_syscalls;
 
-void mars_module_entry(struct mars_kernel_syscalls *syscalls)
-{
-	kernel_syscalls = syscalls;
-
-	asm volatile (
-		/* switch to module stack */
-		"ila	$sp, __stack;"
-
-		/* set module link register to NULL */
-		"il	$lr, 0;"
+/* defined in crt */
+extern void _init(void);
 
-		/* initialize back chain to NULL */
-		"stqd	$lr, 0($sp);"
+/* called by entry.S */
+void __module_entry(struct mars_kernel_syscalls *syscalls);
 
-		/* initialize module stack frame */
-		"stqd	$sp, -32($sp);"
-		"ai	$sp, $sp, -32;"
-
-		/* save link register in link register save area */
-		"stqd	$lr, 16($sp);"
+void __module_entry(struct mars_kernel_syscalls *syscalls)
+{
+	kernel_syscalls = syscalls;
 
-		/* call _init function */
-		"brsl	$lr, _init;"
-	);
+	_init();
 
 	mars_module_main();