// SPDX-License-Identifier: GPL-2.0/* * machine_kexec.c - handle transition of Linux booting another kernel * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com> * * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz * LANDISK/sh4 supported by kogiidena */#include <linux/mm.h>#include <linux/kexec.h>#include <linux/delay.h>#include <linux/reboot.h>#include <linux/numa.h>#include <linux/ftrace.h>#include <linux/suspend.h>#include <linux/memblock.h>#include <asm/mmu_context.h>#include <asm/io.h>#include <asm/cacheflush.h>#include <asm/sh_bios.h>#include <asm/reboot.h> typedef void (*relocate_new_kernel_t)(unsigned long indirection_page,				      unsigned long reboot_code_buffer,				      unsigned long start_address); extern const unsigned char relocate_new_kernel[];extern const unsigned int relocate_new_kernel_size;extern void *vbr_base; void native_machine_crash_shutdown(struct pt_regs *regs){	/* Nothing to do for UP, but definitely broken for SMP.. */} /* * Do what every setup is needed on image and the * reboot code buffer to allow us to avoid allocations * later. */int machine_kexec_prepare(struct kimage *image){	return 0;} void machine_kexec_cleanup(struct kimage *image){} static void kexec_info(struct kimage *image){        int i;	printk("kexec information\n");	for (i = 0; i < image->nr_segments; i++) {	        printk("  segment[%d]: 0x%08x - 0x%08x (0x%08x)\n",		       i,		       (unsigned int)image->segment[i].mem,		       (unsigned int)image->segment[i].mem +				     image->segment[i].memsz,		       (unsigned int)image->segment[i].memsz);	}	printk("  start     : 0x%08x\n\n", (unsigned int)image->start);} /* * Do not allocate memory (or fail in any way) in machine_kexec(). * We are past the point of no return, committed to rebooting now. */void machine_kexec(struct kimage *image){	unsigned long page_list;	unsigned long reboot_code_buffer;	relocate_new_kernel_t rnk;	unsigned long entry;	unsigned long *ptr;	int save_ftrace_enabled; 	/*	 * Nicked from the mips version of machine_kexec():	 * The generic kexec code builds a page list with physical	 * addresses. Use phys_to_virt() to convert them to virtual.	 */	for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);	     ptr = (entry & IND_INDIRECTION) ?	       phys_to_virt(entry & PAGE_MASK) : ptr + 1) {		if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||		    *ptr & IND_DESTINATION)			*ptr = (unsigned long) phys_to_virt(*ptr);	} #ifdef CONFIG_KEXEC_JUMP	if (image->preserve_context)		save_processor_state();#endif 	save_ftrace_enabled = __ftrace_enabled_save(); 	/* Interrupts aren't acceptable while we reboot */	local_irq_disable(); 	page_list = image->head; 	/* we need both effective and real address here */	reboot_code_buffer =			(unsigned long)page_address(image->control_code_page); 	/* copy our kernel relocation code to the control code page */	memcpy((void *)reboot_code_buffer, relocate_new_kernel,						relocate_new_kernel_size); 	kexec_info(image);	flush_cache_all(); 	sh_bios_vbr_reload(); 	/* now call it */	rnk = (relocate_new_kernel_t) reboot_code_buffer;	(*rnk)(page_list, reboot_code_buffer,	       (unsigned long)phys_to_virt(image->start)); #ifdef CONFIG_KEXEC_JUMP	asm volatile("ldc %0, vbr" : : "r" (&vbr_base) : "memory"); 	if (image->preserve_context)		restore_processor_state(); 	/* Convert page list back to physical addresses, what a mess. */	for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);	     ptr = (*ptr & IND_INDIRECTION) ?	       phys_to_virt(*ptr & PAGE_MASK) : ptr + 1) {		if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||		    *ptr & IND_DESTINATION)			*ptr = virt_to_phys(*ptr);	}#endif 	__ftrace_enabled_restore(save_ftrace_enabled);} void __init reserve_crashkernel(void){	unsigned long long crash_size, crash_base;	int ret; 	if (!IS_ENABLED(CONFIG_CRASH_RESERVE))		return; 	ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(),			&crash_size, &crash_base, NULL, NULL, NULL);	if (ret == 0 && crash_size > 0) {		crashk_res.start = crash_base;		crashk_res.end = crash_base + crash_size - 1;	} 	if (crashk_res.end == crashk_res.start)		goto disable; 	crash_size = PAGE_ALIGN(resource_size(&crashk_res));	if (!crashk_res.start) {		unsigned long max = memblock_end_of_DRAM() - memory_limit;		crashk_res.start = memblock_phys_alloc_range(crash_size,							     PAGE_SIZE, 0, max);		if (!crashk_res.start) {			pr_err("crashkernel allocation failed\n");			goto disable;		}	} else {		ret = memblock_reserve(crashk_res.start, crash_size);		if (unlikely(ret < 0)) {			pr_err("crashkernel reservation failed - "			       "memory is in use\n");			goto disable;		}	} 	crashk_res.end = crashk_res.start + crash_size - 1; 	/*	 * Crash kernel trumps memory limit	 */	if ((memblock_end_of_DRAM() - memory_limit) <= crashk_res.end) {		memory_limit = 0;		pr_info("Disabled memory limit for crashkernel\n");	} 	pr_info("Reserving %ldMB of memory at 0x%08lx "		"for crashkernel (System RAM: %ldMB)\n",		(unsigned long)(crash_size >> 20),		(unsigned long)(crashk_res.start),		(unsigned long)(memblock_phys_mem_size() >> 20)); 	return; disable:	crashk_res.start = crashk_res.end = 0;}