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/include/asm/sh_bios.h b/arch/sh/include/asm/sh_bios.h
index d9c96d7cf6c77c77ddeb744a21ea2d7b822c25ca..d8a67a17777c5c88540aefa76e613f7d7fe9e669 100644 (file)
--- a/arch/sh/include/asm/sh_bios.h
+++ b/arch/sh/include/asm/sh_bios.h
@@ -1,13 +1,13 @@
 #ifndef __ASM_SH_BIOS_H
 #define __ASM_SH_BIOS_H
 
+#ifdef CONFIG_SH_STANDARD_BIOS
+
 /*
  * Copyright (C) 2000 Greg Banks, Mitch Davis
  * C API to interface to the standard LinuxSH BIOS
  * usually from within the early stages of kernel boot.
  */
-
-
 extern void sh_bios_console_write(const char *buf, unsigned int len);
 extern void sh_bios_char_out(char ch);
 extern void sh_bios_gdb_detach(void);
@@ -15,4 +15,14 @@ extern void sh_bios_gdb_detach(void);
 extern void sh_bios_get_node_addr(unsigned char *node_addr);
 extern void sh_bios_shutdown(unsigned int how);
 
+extern void sh_bios_vbr_init(void);
+extern void sh_bios_vbr_reload(void);
+
+#else
+
+static inline void sh_bios_vbr_init(void) { }
+static inline void sh_bios_vbr_reload(void) { }
+
+#endif /* CONFIG_SH_STANDARD_BIOS */
+
 #endif /* __ASM_SH_BIOS_H */

diff --git a/arch/sh/kernel/machine_kexec.c b/arch/sh/kernel/machine_kexec.c
index 76f280223ebd1d74abc9493cd83b9e63e3bfca3b..f52d8ed69e125b3e855c4f9043cf3f0c2e5155ce 100644 (file)
--- 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 @@ typedef void (*relocate_new_kernel_t)(unsigned long indirection_page,
 
 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 @@ void machine_kexec(struct kimage *image)
        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 c852f780572803b53ac346eefd3ceed994a20223..2a5f2e0d505d49869075f431e439685e8c2f6963 100644 (file)
--- a/arch/sh/kernel/sh_bios.c
+++ b/arch/sh/kernel/sh_bios.c
@@ -55,3 +55,40 @@ void sh_bios_shutdown(unsigned int how)
 {
        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 86639beac3a2d1d7b32e44e4ded50e1e1329bfdb..efcbdfe52f5212f36a1f1f178e0581cdf24a03a8 100644 (file)
--- 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 @@ asmlinkage void do_exception_error(unsigned long r4, unsigned long r5,
        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 @@ void __init trap_init(void)
        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();
 }