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	 3bdc3484e8
			
		
	
	
		3bdc3484e8
		
	
	
	
	
		
			
			Now that there is a common way to reset the machine, let's use it instead of reinventing the wheel in the kexec backend. Signed-off-by: Will Deacon <will.deacon@arm.com>
		
			
				
	
	
		
			115 lines
		
	
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			115 lines
		
	
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * machine_kexec.c - handle transition of Linux booting another kernel
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|  */
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| 
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| #include <linux/mm.h>
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| #include <linux/kexec.h>
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| #include <linux/delay.h>
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| #include <linux/reboot.h>
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| #include <linux/io.h>
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| #include <asm/pgtable.h>
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| #include <asm/pgalloc.h>
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| #include <asm/mmu_context.h>
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| #include <asm/cacheflush.h>
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| #include <asm/mach-types.h>
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| #include <asm/system.h>
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| 
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| extern const unsigned char relocate_new_kernel[];
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| extern const unsigned int relocate_new_kernel_size;
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| 
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| extern unsigned long kexec_start_address;
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| extern unsigned long kexec_indirection_page;
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| extern unsigned long kexec_mach_type;
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| extern unsigned long kexec_boot_atags;
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| 
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| static atomic_t waiting_for_crash_ipi;
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| 
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| /*
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|  * Provide a dummy crash_notes definition while crash dump arrives to arm.
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|  * This prevents breakage of crash_notes attribute in kernel/ksysfs.c.
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|  */
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| 
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| int machine_kexec_prepare(struct kimage *image)
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| {
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| 	return 0;
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| }
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| 
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| void machine_kexec_cleanup(struct kimage *image)
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| {
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| }
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| 
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| void machine_crash_nonpanic_core(void *unused)
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| {
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| 	struct pt_regs regs;
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| 
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| 	crash_setup_regs(®s, NULL);
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| 	printk(KERN_DEBUG "CPU %u will stop doing anything useful since another CPU has crashed\n",
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| 	       smp_processor_id());
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| 	crash_save_cpu(®s, smp_processor_id());
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| 	flush_cache_all();
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| 
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| 	atomic_dec(&waiting_for_crash_ipi);
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| 	while (1)
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| 		cpu_relax();
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| }
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| 
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| void machine_crash_shutdown(struct pt_regs *regs)
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| {
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| 	unsigned long msecs;
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| 
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| 	local_irq_disable();
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| 
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| 	atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
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| 	smp_call_function(machine_crash_nonpanic_core, NULL, false);
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| 	msecs = 1000; /* Wait at most a second for the other cpus to stop */
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| 	while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
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| 		mdelay(1);
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| 		msecs--;
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| 	}
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| 	if (atomic_read(&waiting_for_crash_ipi) > 0)
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| 		printk(KERN_WARNING "Non-crashing CPUs did not react to IPI\n");
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| 
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| 	crash_save_cpu(regs, smp_processor_id());
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| 
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| 	printk(KERN_INFO "Loading crashdump kernel...\n");
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| }
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| 
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| /*
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|  * Function pointer to optional machine-specific reinitialization
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|  */
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| void (*kexec_reinit)(void);
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| 
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| void machine_kexec(struct kimage *image)
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| {
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| 	unsigned long page_list;
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| 	unsigned long reboot_code_buffer_phys;
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| 	void *reboot_code_buffer;
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| 
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| 
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| 	page_list = image->head & PAGE_MASK;
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| 
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| 	/* we need both effective and real address here */
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| 	reboot_code_buffer_phys =
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| 	    page_to_pfn(image->control_code_page) << PAGE_SHIFT;
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| 	reboot_code_buffer = page_address(image->control_code_page);
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| 
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| 	/* Prepare parameters for reboot_code_buffer*/
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| 	kexec_start_address = image->start;
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| 	kexec_indirection_page = page_list;
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| 	kexec_mach_type = machine_arch_type;
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| 	kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET;
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| 
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| 	/* copy our kernel relocation code to the control code page */
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| 	memcpy(reboot_code_buffer,
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| 	       relocate_new_kernel, relocate_new_kernel_size);
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| 
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| 
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| 	flush_icache_range((unsigned long) reboot_code_buffer,
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| 			   (unsigned long) reboot_code_buffer + KEXEC_CONTROL_PAGE_SIZE);
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| 	printk(KERN_INFO "Bye!\n");
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| 
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| 	if (kexec_reinit)
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| 		kexec_reinit();
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| 
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| 	soft_restart(reboot_code_buffer_phys);
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| }
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