Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit fc697dc0 authored by Sven Schnelle's avatar Sven Schnelle Committed by Helge Deller
Browse files

parisc: add kexec syscall support 



Signed-off-by: default avatarSven Schnelle <svens@stackframe.org>
Signed-off-by: default avatarHelge Deller <deller@gmx.de>
parent 507efd63

arch/parisc/Kconfig

+13 −0
Original line number Diff line number Diff line
@@ -346,6 +346,19 @@ config NR_CPUS 
	depends on SMP

	default "4"



config KEXEC

	bool "Kexec system call"

	select KEXEC_CORE

	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.



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

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

	  initially work for you.



endmenu

arch/parisc/include/asm/fixmap.h

+1 −0
Original line number Diff line number Diff line
@@ -30,6 +30,7 @@ 
enum fixed_addresses {

	/* Support writing RO kernel text via kprobes, jump labels, etc. */

	FIX_TEXT_POKE0,

	FIX_TEXT_KEXEC,

	FIX_BITMAP_COUNT

};

arch/parisc/include/asm/kexec.h

0 → 100644
+37 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#ifndef _ASM_PARISC_KEXEC_H

#define _ASM_PARISC_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_PARISC

#define ARCH_HAS_KIMAGE_ARCH



#ifndef __ASSEMBLY__



struct kimage_arch {

	unsigned long initrd_start;

	unsigned long initrd_end;

	unsigned long cmdline;

};



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_PARISC_KEXEC_H */

arch/parisc/kernel/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -37,3 +37,4 @@ obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o 
obj-$(CONFIG_JUMP_LABEL)		+= jump_label.o

obj-$(CONFIG_KGDB)			+= kgdb.o

obj-$(CONFIG_KPROBES)			+= kprobes.o

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

arch/parisc/kernel/kexec.c

0 → 100644
+105 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0



#include <linux/kernel.h>

#include <linux/console.h>

#include <linux/kexec.h>

#include <linux/delay.h>

#include <asm/cacheflush.h>

#include <asm/sections.h>



extern void relocate_new_kernel(unsigned long head,

				unsigned long start,

				unsigned long phys);



extern const unsigned int relocate_new_kernel_size;

extern unsigned int kexec_initrd_start_offset;

extern unsigned int kexec_initrd_end_offset;

extern unsigned int kexec_cmdline_offset;

extern unsigned int kexec_free_mem_offset;



static void kexec_show_segment_info(const struct kimage *kimage,

				    unsigned long n)

{

	pr_debug("    segment[%lu]: %016lx - %016lx, 0x%lx bytes, %lu pages\n",

			n,

			kimage->segment[n].mem,

			kimage->segment[n].mem + kimage->segment[n].memsz,

			(unsigned long)kimage->segment[n].memsz,

			(unsigned long)kimage->segment[n].memsz /  PAGE_SIZE);

}



static void kexec_image_info(const struct kimage *kimage)

{

	unsigned long i;



	pr_debug("kexec kimage info:\n");

	pr_debug("  type:        %d\n", kimage->type);

	pr_debug("  start:       %lx\n", kimage->start);

	pr_debug("  head:        %lx\n", kimage->head);

	pr_debug("  nr_segments: %lu\n", kimage->nr_segments);



	for (i = 0; i < kimage->nr_segments; i++)

		kexec_show_segment_info(kimage, i);

}



void machine_kexec_cleanup(struct kimage *kimage)

{

}



void machine_crash_shutdown(struct pt_regs *regs)

{

}



void machine_shutdown(void)

{

	smp_send_stop();

	while (num_online_cpus() > 1) {

		cpu_relax();

		mdelay(1);

	}

}



void machine_kexec(struct kimage *image)

{

#ifdef CONFIG_64BIT

	Elf64_Fdesc desc;

#endif

	void (*reloc)(unsigned long head,

		      unsigned long start,

		      unsigned long phys);



	unsigned long phys = page_to_phys(image->control_code_page);

	void *virt = (void *)__fix_to_virt(FIX_TEXT_KEXEC);

	struct kimage_arch *arch = &image->arch;



	set_fixmap(FIX_TEXT_KEXEC, phys);



	flush_cache_all();



#ifdef CONFIG_64BIT

	reloc = (void *)&desc;

	desc.addr = (long long)virt;

#else

	reloc = (void *)virt;

#endif



	memcpy(virt, dereference_function_descriptor(relocate_new_kernel),

		relocate_new_kernel_size);



	*(unsigned long *)(virt + kexec_cmdline_offset) = arch->cmdline;

	*(unsigned long *)(virt + kexec_initrd_start_offset) = arch->initrd_start;

	*(unsigned long *)(virt + kexec_initrd_end_offset) = arch->initrd_end;

	*(unsigned long *)(virt + kexec_free_mem_offset) = PAGE0->mem_free;



	flush_cache_all();

	flush_tlb_all();

	local_irq_disable();



	reloc(image->head & PAGE_MASK, image->start, phys);

}



int machine_kexec_prepare(struct kimage *image)

{

	kexec_image_info(image);

	return 0;

}