1 files changed, 162 insertions, 0 deletions
diff --git a/arch/powerpc/purgatory/trampoline_64.S b/arch/powerpc/purgatory/trampoline_64.S
new file mode 100644
index 000000000000..b35837c13852
--- /dev/null
+++ b/arch/powerpc/purgatory/trampoline_64.S
@@ -0,0 +1,162 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * kexec trampoline
+ *
+ * Based on code taken from kexec-tools and kexec-lite.
+ *
+ * Copyright (C) 2004 - 2005, Milton D Miller II, IBM Corporation
+ * Copyright (C) 2006, Mohan Kumar M, IBM Corporation
+ * Copyright (C) 2013, Anton Blanchard, IBM Corporation
+ */
+
+#include <asm/asm-compat.h>
+#include <asm/crashdump-ppc64.h>
+
+	.balign 256
+	.globl purgatory_start
+purgatory_start:
+	b	master
+
+	/* ABI: possible run_at_load flag at 0x5c */
+	.org purgatory_start + 0x5c
+	.globl run_at_load
+run_at_load:
+	.long 0
+	.size run_at_load, . - run_at_load
+
+	/* ABI: slaves start at 60 with r3=phys */
+	.org purgatory_start + 0x60
+slave:
+	b .
+	/* ABI: end of copied region */
+	.org purgatory_start + 0x100
+	.size purgatory_start, . - purgatory_start
+
+/*
+ * The above 0x100 bytes at purgatory_start are replaced with the
+ * code from the kernel (or next stage) by setup_purgatory().
+ */
+
+master:
+	or	%r1,%r1,%r1	/* low priority to let other threads catchup */
+	isync
+	mr	%r17,%r3	/* save cpu id to r17 */
+	mr	%r15,%r4	/* save physical address in reg15 */
+
+	/* Work out where we're running */
+	bcl	20, 31, 0f
+0:	mflr	%r18
+
+	/*
+	 * Copy BACKUP_SRC_SIZE bytes from BACKUP_SRC_START to
+	 * backup_start 8 bytes at a time.
+	 *
+	 * Use r3 = dest, r4 = src, r5 = size, r6 = count
+	 */
+	ld	%r3, (backup_start - 0b)(%r18)
+	cmpdi	%cr0, %r3, 0
+	beq	.Lskip_copy	/* skip if there is no backup region */
+	lis	%r5, BACKUP_SRC_SIZE@h
+	ori	%r5, %r5, BACKUP_SRC_SIZE@l
+	cmpdi	%cr0, %r5, 0
+	beq	.Lskip_copy	/* skip if copy size is zero */
+	lis	%r4, BACKUP_SRC_START@h
+	ori	%r4, %r4, BACKUP_SRC_START@l
+	li	%r6, 0
+.Lcopy_loop:
+	ldx	%r0, %r6, %r4
+	stdx	%r0, %r6, %r3
+	addi	%r6, %r6, 8
+	cmpld	%cr0, %r6, %r5
+	blt	.Lcopy_loop
+
+.Lskip_copy:
+	or	%r3,%r3,%r3	/* ok now to high priority, lets boot */
+	lis	%r6,0x1
+	mtctr	%r6		/* delay a bit for slaves to catch up */
+	bdnz	.		/* before we overwrite 0-100 again */
+
+	/* load device-tree address */
+	ld	%r3, (dt_offset - 0b)(%r18)
+	mr	%r16,%r3	/* save dt address in reg16 */
+	li	%r4,20
+	LWZX_BE	%r6,%r3,%r4	/* fetch __be32 version number at byte 20 */
+	cmpwi	%cr0,%r6,2	/* v2 or later? */
+	blt	1f
+	li	%r4,28
+	STWX_BE	%r17,%r3,%r4	/* Store my cpu as __be32 at byte 28 */
+1:
+	/* Load opal base and entry values in r8 & r9 respectively */
+	ld	%r8,(opal_base - 0b)(%r18)
+	ld	%r9,(opal_entry - 0b)(%r18)
+
+	/* load the kernel address */
+	ld	%r4,(kernel - 0b)(%r18)
+
+	/* load the run_at_load flag */
+	/* possibly patched by kexec */
+	ld	%r6,(run_at_load - 0b)(%r18)
+	/* and patch it into the kernel */
+	stw	%r6,(0x5c)(%r4)
+
+	mr	%r3,%r16	/* restore dt address */
+
+	li	%r5,0		/* r5 will be 0 for kernel */
+
+	mfmsr	%r11
+	andi.	%r10,%r11,1	/* test MSR_LE */
+	bne	.Little_endian
+
+	mtctr	%r4		/* prepare branch to */
+	bctr			/* start kernel */
+
+.Little_endian:
+	mtsrr0	%r4		/* prepare branch to */
+
+	clrrdi	%r11,%r11,1	/* clear MSR_LE */
+	mtsrr1	%r11
+
+	rfid			/* update MSR and start kernel */
+
+	.balign 8
+	.globl kernel
+kernel:
+	.8byte  0x0
+	.size kernel, . - kernel
+
+	.balign 8
+	.globl dt_offset
+dt_offset:
+	.8byte  0x0
+	.size dt_offset, . - dt_offset
+
+	.balign 8
+	.globl backup_start
+backup_start:
+	.8byte  0x0
+	.size backup_start, . - backup_start
+
+	.balign 8
+	.globl opal_base
+opal_base:
+	.8byte  0x0
+	.size opal_base, . - opal_base
+
+	.balign 8
+	.globl opal_entry
+opal_entry:
+	.8byte  0x0
+	.size opal_entry, . - opal_entry
+
+	.data
+	.balign 8
+.globl purgatory_sha256_digest
+purgatory_sha256_digest:
+	.skip	32
+	.size purgatory_sha256_digest, . - purgatory_sha256_digest
+
+	.balign 8
+.globl purgatory_sha_regions
+purgatory_sha_regions:
+	.skip	8 * 2 * 16
+	.size purgatory_sha_regions, . - purgatory_sha_regions