/* SPDX-License-Identifier: GPL-2.0-only *//* * kexec for arm64 * * Copyright (C) Linaro. * Copyright (C) Huawei Futurewei Technologies. */ #include <linux/kexec.h>#include <linux/linkage.h> #include <asm/assembler.h>#include <asm/kexec.h>#include <asm/page.h>#include <asm/sysreg.h> /* * arm64_relocate_new_kernel - Put a 2nd stage image in place and boot it. * * The memory that the old kernel occupies may be overwritten when copying the * new image to its final location.  To assure that the * arm64_relocate_new_kernel routine which does that copy is not overwritten, * all code and data needed by arm64_relocate_new_kernel must be between the * symbols arm64_relocate_new_kernel and arm64_relocate_new_kernel_end.  The * machine_kexec() routine will copy arm64_relocate_new_kernel to the kexec * safe memory that has been set up to be preserved during the copy operation. */SYM_CODE_START(arm64_relocate_new_kernel)	/* Setup the list loop variables. */	mov	x18, x2				/* x18 = dtb address */	mov	x17, x1				/* x17 = kimage_start */	mov	x16, x0				/* x16 = kimage_head */	mov	x14, xzr			/* x14 = entry ptr */	mov	x13, xzr			/* x13 = copy dest */	/* Check if the new image needs relocation. */	tbnz	x16, IND_DONE_BIT, .Ldone	raw_dcache_line_size x15, x1		/* x15 = dcache line size */.Lloop:	and	x12, x16, PAGE_MASK		/* x12 = addr */ 	/* Test the entry flags. */.Ltest_source:	tbz	x16, IND_SOURCE_BIT, .Ltest_indirection 	/* Invalidate dest page to PoC. */	mov     x2, x13	add     x20, x2, #PAGE_SIZE	sub     x1, x15, #1	bic     x2, x2, x12:	dc      ivac, x2	add     x2, x2, x15	cmp     x2, x20	b.lo    2b	dsb     sy 	copy_page x13, x12, x1, x2, x3, x4, x5, x6, x7, x8	b	.Lnext.Ltest_indirection:	tbz	x16, IND_INDIRECTION_BIT, .Ltest_destination	mov	x14, x12			/* ptr = addr */	b	.Lnext.Ltest_destination:	tbz	x16, IND_DESTINATION_BIT, .Lnext	mov	x13, x12			/* dest = addr */.Lnext:	ldr	x16, [x14], #8			/* entry = *ptr++ */	tbz	x16, IND_DONE_BIT, .Lloop	/* while (!(entry & DONE)) */.Ldone:	/* wait for writes from copy_page to finish */	dsb	nsh	ic	iallu	dsb	nsh	isb 	/* Start new image. */	mov	x0, x18	mov	x1, xzr	mov	x2, xzr	mov	x3, xzr	br	x17 SYM_CODE_END(arm64_relocate_new_kernel) .align 3	/* To keep the 64-bit values below naturally aligned. */ .Lcopy_end:.org	KEXEC_CONTROL_PAGE_SIZE /* * arm64_relocate_new_kernel_size - Number of bytes to copy to the * control_code_page. */.globl arm64_relocate_new_kernel_sizearm64_relocate_new_kernel_size:	.quad	.Lcopy_end - arm64_relocate_new_kernel