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Commit 191d0d24 authored by Paul Mundt's avatar Paul Mundt
Browse files

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: default avatarPaul Mundt <lethal@linux-sh.org>
parent ee2760ea

arch/sh/include/asm/sh_bios.h

+12 −2
Original line number Diff line number Diff line 
#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 */

arch/sh/kernel/machine_kexec.c

+2 −6
Original line number Diff line number Diff line
@@ -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;

arch/sh/kernel/sh_bios.c

+37 −0
Original line number Diff line number Diff line
@@ -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"

		);

}

arch/sh/kernel/traps_32.c

+4 −25
Original line number Diff line number Diff line
@@ -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();

}