sh: Tidy up the sh bios VBR handling.
This moves the VBR handling out of the main trap handling code and in to
the sh-bios helper code. A couple of accessors are added in order to
permit other kernel code to get at the VBR value for state save/restore
paths.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/kernel/machine_kexec.c b/arch/sh/kernel/machine_kexec.c
index 76f2802..f52d8ed 100644
--- a/arch/sh/kernel/machine_kexec.c
+++ b/arch/sh/kernel/machine_kexec.c
@@ -21,6 +21,7 @@
#include <asm/mmu_context.h>
#include <asm/io.h>
#include <asm/cacheflush.h>
+#include <asm/sh_bios.h>
typedef void (*relocate_new_kernel_t)(unsigned long indirection_page,
unsigned long reboot_code_buffer,
@@ -28,7 +29,6 @@
extern const unsigned char relocate_new_kernel[];
extern const unsigned int relocate_new_kernel_size;
-extern void *gdb_vbr_vector;
extern void *vbr_base;
void machine_shutdown(void)
@@ -117,11 +117,7 @@
kexec_info(image);
flush_cache_all();
-#if defined(CONFIG_SH_STANDARD_BIOS)
- asm volatile("ldc %0, vbr" :
- : "r" (((unsigned long) gdb_vbr_vector) - 0x100)
- : "memory");
-#endif
+ sh_bios_vbr_reload();
/* now call it */
rnk = (relocate_new_kernel_t) reboot_code_buffer;
diff --git a/arch/sh/kernel/sh_bios.c b/arch/sh/kernel/sh_bios.c
index c852f78..2a5f2e0 100644
--- a/arch/sh/kernel/sh_bios.c
+++ b/arch/sh/kernel/sh_bios.c
@@ -55,3 +55,40 @@
{
sh_bios_call(BIOS_CALL_SHUTDOWN, how, 0, 0, 0);
}
+
+void *gdb_vbr_vector = NULL;
+
+/*
+ * Read the old value of the VBR register to initialise the vector
+ * through which debug and BIOS traps are delegated by the Linux trap
+ * handler.
+ */
+void sh_bios_vbr_init(void)
+{
+ unsigned long vbr;
+
+ if (unlikely(gdb_vbr_vector))
+ return;
+
+ __asm__ __volatile__ ("stc vbr, %0" : "=r" (vbr));
+
+ gdb_vbr_vector = (void *)(vbr + 0x100);
+ printk(KERN_NOTICE "Setting GDB trap vector to %p\n", gdb_vbr_vector);
+}
+
+/**
+ * sh_bios_vbr_reload - Re-load the system VBR from the BIOS vector.
+ *
+ * This can be used by save/restore code to reinitialize the system VBR
+ * from the fixed BIOS VBR. A no-op if no BIOS VBR is known.
+ */
+void sh_bios_vbr_reload(void)
+{
+ if (gdb_vbr_vector)
+ __asm__ __volatile__ (
+ "ldc %0, vbr"
+ :
+ : "r" (((unsigned long) gdb_vbr_vector) - 0x100)
+ : "memory"
+ );
+}
diff --git a/arch/sh/kernel/traps_32.c b/arch/sh/kernel/traps_32.c
index 86639be..efcbdfe 100644
--- a/arch/sh/kernel/traps_32.c
+++ b/arch/sh/kernel/traps_32.c
@@ -31,6 +31,7 @@
#include <asm/uaccess.h>
#include <asm/fpu.h>
#include <asm/kprobes.h>
+#include <asm/sh_bios.h>
#ifdef CONFIG_CPU_SH2
# define TRAP_RESERVED_INST 4
@@ -876,35 +877,10 @@
die_if_kernel("exception", regs, ex);
}
-#if defined(CONFIG_SH_STANDARD_BIOS)
-void *gdb_vbr_vector;
-
-static inline void __init gdb_vbr_init(void)
-{
- register unsigned long vbr;
-
- /*
- * Read the old value of the VBR register to initialise
- * the vector through which debug and BIOS traps are
- * delegated by the Linux trap handler.
- */
- asm volatile("stc vbr, %0" : "=r" (vbr));
-
- gdb_vbr_vector = (void *)(vbr + 0x100);
- printk("Setting GDB trap vector to 0x%08lx\n",
- (unsigned long)gdb_vbr_vector);
-}
-#endif
-
void __cpuinit per_cpu_trap_init(void)
{
extern void *vbr_base;
-#ifdef CONFIG_SH_STANDARD_BIOS
- if (raw_smp_processor_id() == 0)
- gdb_vbr_init();
-#endif
-
/* NOTE: The VBR value should be at P1
(or P2, virtural "fixed" address space).
It's definitely should not in physical address. */
@@ -959,6 +935,9 @@
set_exception_table_vec(TRAP_UBC, break_point_trap);
#endif
+ /* Save off the BIOS VBR, if there is one */
+ sh_bios_vbr_init();
+
/* Setup VBR for boot cpu */
per_cpu_trap_init();
}