Commit 7d5f5fa2 authored by Geert Uytterhoeven's avatar Geert Uytterhoeven
Browse files

m68k: Add kexec support 



Signed-off-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
parent 6cf30b35

arch/m68k/Kconfig

+17 −0
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@@ -87,6 +87,23 @@ config MMU_SUN3 
	bool

	depends on MMU && !MMU_MOTOROLA && !MMU_COLDFIRE



config KEXEC

	bool "kexec system call"

	depends on M68KCLASSIC

	help

	  kexec is a system call that implements the ability to shutdown your

	  current kernel, and to start another kernel.  It is like a reboot

	  but it is independent of the system firmware.   And like a reboot

	  you can start any kernel with it, not just Linux.



	  The name comes from the similarity to the exec system call.



	  It is an ongoing process to be certain the hardware in a machine

	  is properly shutdown, so do not be surprised if this code does not

	  initially work for you.  As of this writing the exact hardware

	  interface is strongly in flux, so no good recommendation can be

	  made.



menu "Platform setup"



source arch/m68k/Kconfig.cpu

arch/m68k/include/asm/kexec.h

0 → 100644
+29 −0
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#ifndef _ASM_M68K_KEXEC_H

#define _ASM_M68K_KEXEC_H



#ifdef CONFIG_KEXEC



/* Maximum physical address we can use pages from */

#define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)

/* Maximum address we can reach in physical address mode */

#define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)

/* Maximum address we can use for the control code buffer */

#define KEXEC_CONTROL_MEMORY_LIMIT (-1UL)



#define KEXEC_CONTROL_PAGE_SIZE	4096



#define KEXEC_ARCH KEXEC_ARCH_68K



#ifndef __ASSEMBLY__



static inline void crash_setup_regs(struct pt_regs *newregs,

				    struct pt_regs *oldregs)

{

	/* Dummy implementation for now */

}



#endif /* __ASSEMBLY__ */



#endif /* CONFIG_KEXEC */



#endif /* _ASM_M68K_KEXEC_H */

arch/m68k/kernel/Makefile

+2 −0
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@@ -22,3 +22,5 @@ obj-$(CONFIG_PCI) += pcibios.o 


obj-$(CONFIG_HAS_DMA)	+= dma.o



obj-$(CONFIG_KEXEC)		+= machine_kexec.o relocate_kernel.o

arch/m68k/kernel/asm-offsets.c

+3 −0
Original line number Diff line number Diff line
@@ -98,6 +98,9 @@ int main(void) 
	DEFINE(CIABBASE, &ciab);

	DEFINE(C_PRA, offsetof(struct CIA, pra));

	DEFINE(ZTWOBASE, zTwoBase);



	/* enum m68k_fixup_type */

	DEFINE(M68K_FIXUP_MEMOFFSET, m68k_fixup_memoffset);

#endif



	return 0;

arch/m68k/kernel/machine_kexec.c

0 → 100644
+58 −0
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/*

 * machine_kexec.c - handle transition of Linux booting another kernel

 */

#include <linux/compiler.h>

#include <linux/kexec.h>

#include <linux/mm.h>

#include <linux/delay.h>



#include <asm/cacheflush.h>

#include <asm/page.h>

#include <asm/setup.h>



extern const unsigned char relocate_new_kernel[];

extern const size_t relocate_new_kernel_size;



int machine_kexec_prepare(struct kimage *kimage)

{

	return 0;

}



void machine_kexec_cleanup(struct kimage *kimage)

{

}



void machine_shutdown(void)

{

}



void machine_crash_shutdown(struct pt_regs *regs)

{

}



typedef void (*relocate_kernel_t)(unsigned long ptr,

				  unsigned long start,

				  unsigned long cpu_mmu_flags) __noreturn;



void machine_kexec(struct kimage *image)

{

	void *reboot_code_buffer;

	unsigned long cpu_mmu_flags;



	reboot_code_buffer = page_address(image->control_code_page);



	memcpy(reboot_code_buffer, relocate_new_kernel,

	       relocate_new_kernel_size);



	/*

	 * we do not want to be bothered.

	 */

	local_irq_disable();



	pr_info("Will call new kernel at 0x%08lx. Bye...\n", image->start);

	__flush_cache_all();

	cpu_mmu_flags = m68k_cputype | m68k_mmutype << 8;

	((relocate_kernel_t) reboot_code_buffer)(image->head & PAGE_MASK,

						 image->start,

						 cpu_mmu_flags);

}