Message-Id: <1477017617-8540-10-git-send-email-bauerman@linux.vnet.ibm.com>
Date:   Fri, 21 Oct 2016 00:40:16 -0200
From:   Thiago Jung Bauermann <bauerman@...ux.vnet.ibm.com>
To:     kexec@...ts.infradead.org
Cc:     linuxppc-dev@...ts.ozlabs.org, linux-kernel@...r.kernel.org,
        x86@...nel.org, Eric Biederman <ebiederm@...ssion.com>,
        Dave Young <dyoung@...hat.com>,
        Vivek Goyal <vgoyal@...hat.com>, Baoquan He <bhe@...hat.com>,
        Michael Ellerman <mpe@...erman.id.au>,
        Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Paul Mackerras <paulus@...ba.org>,
        Stewart Smith <stewart@...ux.vnet.ibm.com>,
        Mimi Zohar <zohar@...ux.vnet.ibm.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        "H. Peter Anvin" <hpa@...or.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Stephen Rothwell <sfr@...b.auug.org.au>,
        Thiago Jung Bauermann <bauerman@...ux.vnet.ibm.com>
Subject: [PATCH v9 09/10] powerpc: Add purgatory for kexec_file_load implementation.

This purgatory implementation comes from kexec-tools, almost unchanged.

In order to use boot/string.S in ppc64 big endian mode, the functions
defined in it need to have dot symbols so that they can be called from C
code. Therefore, change the file to use a DOTSYM macro if one is defined,
so that the purgatory can add those dot symbols.

The changes made to the purgatory code relative to the version in
kexec-tools were:

The sha256_regions global variable was renamed to sha_regions to match
what kexec_file_load expects, and to use the sha256.c file from x86's
purgatory (this avoids adding yet another SHA-256 implementation).

The global variables in purgatory.c and purgatory-ppc64.c now use a
__section attribute to put them in the .data section instead of being
initialized to zero. It doesn't matter what their initial value is,
because they will be set by the kernel when preparing the kexec image.

Also, since we don't support loading a crashdump kernel via
kexec_file_load yet, the code related to that functionality has been
removed.

Finally, some checkpatch.pl warnings were fixed.

Signed-off-by: Thiago Jung Bauermann <bauerman@...ux.vnet.ibm.com>
---
 arch/powerpc/Makefile                    |   1 +
 arch/powerpc/boot/string.S               |  67 +++++++------
 arch/powerpc/purgatory/.gitignore        |   2 +
 arch/powerpc/purgatory/Makefile          |  33 +++++++
 arch/powerpc/purgatory/console-ppc64.c   |  37 +++++++
 arch/powerpc/purgatory/crtsavres.S       |   5 +
 arch/powerpc/purgatory/hvCall.S          |  27 +++++
 arch/powerpc/purgatory/hvCall.h          |   8 ++
 arch/powerpc/purgatory/kexec-sha256.h    |  11 +++
 arch/powerpc/purgatory/ppc64_asm.h       |  20 ++++
 arch/powerpc/purgatory/printf.c          | 164 +++++++++++++++++++++++++++++++
 arch/powerpc/purgatory/purgatory-ppc64.c |  36 +++++++
 arch/powerpc/purgatory/purgatory.c       |  62 ++++++++++++
 arch/powerpc/purgatory/purgatory.h       |  14 +++
 arch/powerpc/purgatory/sha256.c          |   6 ++
 arch/powerpc/purgatory/sha256.h          |   1 +
 arch/powerpc/purgatory/string.S          |   2 +
 arch/powerpc/purgatory/v2wrap.S          | 134 +++++++++++++++++++++++++
 18 files changed, 601 insertions(+), 29 deletions(-)

diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 617dece67924..5e7dcdaf93f5 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -249,6 +249,7 @@ core-y				+= arch/powerpc/kernel/ \
 core-$(CONFIG_XMON)		+= arch/powerpc/xmon/
 core-$(CONFIG_KVM) 		+= arch/powerpc/kvm/
 core-$(CONFIG_PERF_EVENTS)	+= arch/powerpc/perf/
+core-$(CONFIG_KEXEC_FILE)	+= arch/powerpc/purgatory/
 
 drivers-$(CONFIG_OPROFILE)	+= arch/powerpc/oprofile/
 
diff --git a/arch/powerpc/boot/string.S b/arch/powerpc/boot/string.S
index acc9428f2789..b54bbad5f83d 100644
--- a/arch/powerpc/boot/string.S
+++ b/arch/powerpc/boot/string.S
@@ -11,9 +11,18 @@
 
 #include "ppc_asm.h"
 
+/*
+ * The ppc64 kexec purgatory uses this file and packages it in ELF64,
+ * so it needs dot symbols for the ppc64 big endian ABI. This macro
+ * allows it to create those symbols.
+ */
+#ifndef DOTSYM
+#define DOTSYM(a)	a
+#endif
+
 	.text
-	.globl	strcpy
-strcpy:
+	.globl	DOTSYM(strcpy)
+DOTSYM(strcpy):
 	addi	r5,r3,-1
 	addi	r4,r4,-1
 1:	lbzu	r0,1(r4)
@@ -22,8 +31,8 @@ strcpy:
 	bne	1b
 	blr
 
-	.globl	strncpy
-strncpy:
+	.globl	DOTSYM(strncpy)
+DOTSYM(strncpy):
 	cmpwi	0,r5,0
 	beqlr
 	mtctr	r5
@@ -35,8 +44,8 @@ strncpy:
 	bdnzf	2,1b		/* dec ctr, branch if ctr != 0 && !cr0.eq */
 	blr
 
-	.globl	strcat
-strcat:
+	.globl	DOTSYM(strcat)
+DOTSYM(strcat):
 	addi	r5,r3,-1
 	addi	r4,r4,-1
 1:	lbzu	r0,1(r5)
@@ -49,8 +58,8 @@ strcat:
 	bne	1b
 	blr
 
-	.globl	strchr
-strchr:
+	.globl	DOTSYM(strchr)
+DOTSYM(strchr):
 	addi	r3,r3,-1
 1:	lbzu	r0,1(r3)
 	cmpw	0,r0,r4
@@ -60,8 +69,8 @@ strchr:
 	li	r3,0
 	blr
 
-	.globl	strcmp
-strcmp:
+	.globl	DOTSYM(strcmp)
+DOTSYM(strcmp):
 	addi	r5,r3,-1
 	addi	r4,r4,-1
 1:	lbzu	r3,1(r5)
@@ -72,8 +81,8 @@ strcmp:
 	beq	1b
 	blr
 
-	.globl	strncmp
-strncmp:
+	.globl	DOTSYM(strncmp)
+DOTSYM(strncmp):
 	mtctr	r5
 	addi	r5,r3,-1
 	addi	r4,r4,-1
@@ -85,8 +94,8 @@ strncmp:
 	bdnzt	eq,1b
 	blr
 
-	.globl	strlen
-strlen:
+	.globl	DOTSYM(strlen)
+DOTSYM(strlen):
 	addi	r4,r3,-1
 1:	lbzu	r0,1(r4)
 	cmpwi	0,r0,0
@@ -94,8 +103,8 @@ strlen:
 	subf	r3,r3,r4
 	blr
 
-	.globl	memset
-memset:
+	.globl	DOTSYM(memset)
+DOTSYM(memset):
 	rlwimi	r4,r4,8,16,23
 	rlwimi	r4,r4,16,0,15
 	addi	r6,r3,-4
@@ -120,14 +129,14 @@ memset:
 	bdnz	8b
 	blr
 
-	.globl	memmove
-memmove:
+	.globl	DOTSYM(memmove)
+DOTSYM(memmove):
 	cmplw	0,r3,r4
-	bgt	backwards_memcpy
+	bgt	DOTSYM(backwards_memcpy)
 	/* fall through */
 
-	.globl	memcpy
-memcpy:
+	.globl	DOTSYM(memcpy)
+DOTSYM(memcpy):
 	rlwinm.	r7,r5,32-3,3,31		/* r7 = r5 >> 3 */
 	addi	r6,r3,-4
 	addi	r4,r4,-4
@@ -175,8 +184,8 @@ memcpy:
 	mtctr	r7
 	b	1b
 
-	.globl	backwards_memcpy
-backwards_memcpy:
+	.globl	DOTSYM(backwards_memcpy)
+DOTSYM(backwards_memcpy):
 	rlwinm.	r7,r5,32-3,3,31		/* r7 = r5 >> 3 */
 	add	r6,r3,r5
 	add	r4,r4,r5
@@ -219,8 +228,8 @@ backwards_memcpy:
 	mtctr	r7
 	b	1b
 
-	.globl	memchr
-memchr:
+	.globl	DOTSYM(memchr)
+DOTSYM(memchr):
 	cmpwi	0,r5,0
 	blelr
 	mtctr	r5
@@ -232,8 +241,8 @@ memchr:
 	li	r3,0
 	blr
 
-	.globl	memcmp
-memcmp:
+	.globl	DOTSYM(memcmp)
+DOTSYM(memcmp):
 	cmpwi	0,r5,0
 	ble	2f
 	mtctr	r5
@@ -253,8 +262,8 @@ memcmp:
  *
  * flush_cache(addr, len)
  */
-	.global	flush_cache
-flush_cache:
+	.globl	DOTSYM(flush_cache)
+DOTSYM(flush_cache):
 	addi	4,4,0x1f	/* len = (len + 0x1f) / 0x20 */
 	rlwinm.	4,4,27,5,31
 	mtctr	4
diff --git a/arch/powerpc/purgatory/.gitignore b/arch/powerpc/purgatory/.gitignore
new file mode 100644
index 000000000000..e9e66f178a6d
--- /dev/null
+++ b/arch/powerpc/purgatory/.gitignore
@@ -0,0 +1,2 @@
+kexec-purgatory.c
+purgatory.ro
diff --git a/arch/powerpc/purgatory/Makefile b/arch/powerpc/purgatory/Makefile
new file mode 100644
index 000000000000..32822234b049
--- /dev/null
+++ b/arch/powerpc/purgatory/Makefile
@@ -0,0 +1,33 @@
+OBJECT_FILES_NON_STANDARD := y
+
+purgatory-y := purgatory.o printf.o string.o v2wrap.o hvCall.o \
+		purgatory-ppc64.o console-ppc64.o  crtsavres.o sha256.o
+
+targets += $(purgatory-y)
+PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y))
+
+LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined -nostartfiles \
+			-nostdlib -nodefaultlibs
+targets += purgatory.ro
+
+KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_FTRACE), $(KBUILD_CFLAGS))
+
+KBUILD_CFLAGS += -fno-zero-initialized-in-bss -fno-builtin -ffreestanding \
+		 -fno-stack-protector -fno-exceptions -fpie
+KBUILD_AFLAGS += -fno-exceptions -msoft-float -fpie
+
+$(obj)/purgatory.ro: $(PURGATORY_OBJS) FORCE
+		$(call if_changed,ld)
+
+targets += kexec-purgatory.c
+
+CMD_BIN2C = $(objtree)/scripts/basic/bin2c
+quiet_cmd_bin2c = BIN2C   $@
+      cmd_bin2c = $(CMD_BIN2C) kexec_purgatory < $< > $@
+
+$(obj)/kexec-purgatory.c: $(obj)/purgatory.ro FORCE
+	$(call if_changed,bin2c)
+	@:
+
+
+obj-$(CONFIG_KEXEC_FILE)	+= kexec-purgatory.o
diff --git a/arch/powerpc/purgatory/console-ppc64.c b/arch/powerpc/purgatory/console-ppc64.c
new file mode 100644
index 000000000000..8c89686fa340
--- /dev/null
+++ b/arch/powerpc/purgatory/console-ppc64.c
@@ -0,0 +1,37 @@
+/*
+ * kexec: Linux boots Linux
+ *
+ * Created by: Mohan Kumar M (mohan@...ibm.com)
+ *
+ * Copyright (C) IBM Corporation, 2005. All rights reserved
+ *
+ * Code taken from kexec-tools.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation (version 2 of the License).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include "hvCall.h"
+#include <asm/byteorder.h>
+#include "purgatory.h"
+
+void putchar(int c)
+{
+	char buff[8];
+	unsigned long *lbuf = (unsigned long *)buff;
+
+	if (!debug) /* running on non pseries */
+		return;
+
+	if (c == '\n')
+		putchar('\r');
+
+	buff[0] = c;
+	plpar_hcall_norets(H_PUT_TERM_CHAR, 0, 1, __cpu_to_be64(*lbuf), 0);
+}
diff --git a/arch/powerpc/purgatory/crtsavres.S b/arch/powerpc/purgatory/crtsavres.S
new file mode 100644
index 000000000000..5d17e1c0d575
--- /dev/null
+++ b/arch/powerpc/purgatory/crtsavres.S
@@ -0,0 +1,5 @@
+#ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE
+#define CONFIG_CC_OPTIMIZE_FOR_SIZE 1
+#endif
+
+#include "../lib/crtsavres.S"
diff --git a/arch/powerpc/purgatory/hvCall.S b/arch/powerpc/purgatory/hvCall.S
new file mode 100644
index 000000000000..a96c4898f1d8
--- /dev/null
+++ b/arch/powerpc/purgatory/hvCall.S
@@ -0,0 +1,27 @@
+/*
+ * This file contains the generic function to perform a call to the
+ * pSeries LPAR hypervisor.
+ *
+ * Taken from linux/arch/powerpc/platforms/pseries/hvCall.S
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#include "ppc64_asm.h"
+
+#define HVSC	.long 0x44000022
+.text
+	.machine ppc64
+.globl DOTSYM(plpar_hcall_norets)
+DOTSYM(plpar_hcall_norets):
+	or	6,6,6			# medium low priority
+        mfcr	0
+        stw	0,8(1)
+
+        HVSC 				/* invoke the hypervisor */
+
+        lwz	0,8(1)
+        mtcrf	0xff,0
+        blr                             /* return r3 = status */
diff --git a/arch/powerpc/purgatory/hvCall.h b/arch/powerpc/purgatory/hvCall.h
new file mode 100644
index 000000000000..187e24d8b964
--- /dev/null
+++ b/arch/powerpc/purgatory/hvCall.h
@@ -0,0 +1,8 @@
+#ifndef HVCALL_H
+#define HVCALL_H
+
+#define H_PUT_TERM_CHAR	0x58
+
+long plpar_hcall_norets(unsigned long opcode, ...);
+
+#endif
diff --git a/arch/powerpc/purgatory/kexec-sha256.h b/arch/powerpc/purgatory/kexec-sha256.h
new file mode 100644
index 000000000000..4418ed02c052
--- /dev/null
+++ b/arch/powerpc/purgatory/kexec-sha256.h
@@ -0,0 +1,11 @@
+#ifndef KEXEC_SHA256_H
+#define KEXEC_SHA256_H
+
+struct kexec_sha_region {
+	unsigned long start;
+	unsigned long len;
+};
+
+#define SHA256_REGIONS 16
+
+#endif /* KEXEC_SHA256_H */
diff --git a/arch/powerpc/purgatory/ppc64_asm.h b/arch/powerpc/purgatory/ppc64_asm.h
new file mode 100644
index 000000000000..95d721718237
--- /dev/null
+++ b/arch/powerpc/purgatory/ppc64_asm.h
@@ -0,0 +1,20 @@
+/*
+ * ppc64_asm.h - common defines for PPC64 assembly parts
+ *
+ * Code taken from kexec-tools.
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2.  See the file COPYING for more details.
+ */
+
+#include <asm/types.h>
+
+/*
+ * ABIv1 requires dot symbol while ABIv2 does not.
+ */
+#ifdef PPC64_ELF_ABI_v2
+#define DOTSYM(a)	a
+#else
+#define GLUE(a, b)	a##b
+#define DOTSYM(a)	GLUE(., a)
+#endif
diff --git a/arch/powerpc/purgatory/printf.c b/arch/powerpc/purgatory/printf.c
new file mode 100644
index 000000000000..c5f425b55fd5
--- /dev/null
+++ b/arch/powerpc/purgatory/printf.c
@@ -0,0 +1,164 @@
+/*
+ * Code taken from kexec-tools.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation (version 2 of the License).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <stdarg.h>
+#include "purgatory.h"
+#include "../boot/string.h"
+
+#define CHAR_BIT 8
+
+/*
+ * Output
+ * =============================================================================
+ */
+
+#define LONG_LONG_SHIFT  ((int)((sizeof(unsigned long long)*CHAR_BIT) - 4))
+#define LONG_SHIFT  ((int)((sizeof(unsigned long)*CHAR_BIT) - 4))
+#define INT_SHIFT   ((int)((sizeof(unsigned int)*CHAR_BIT) - 4))
+#define SHRT_SHIFT  ((int)((sizeof(unsigned short)*CHAR_BIT) - 4))
+#define CHAR_SHIFT  ((int)((sizeof(unsigned char)*CHAR_BIT) - 4))
+
+/**************************************************************************
+PRINTF and friends
+
+	Formats:
+		%x	- 4 bytes int (8 hex digits, lower case)
+		%X	- 4 bytes int (8 hex digits, upper case)
+		%lx     - 8 bytes long (16 hex digits, lower case)
+		%lX     - 8 bytes long (16 hex digits, upper case)
+		%hx	- 2 bytes int (4 hex digits, lower case)
+		%hX	- 2 bytes int (4 hex digits, upper case)
+		%hhx	- 1 byte int (2 hex digits, lower case)
+		%hhX	- 1 byte int (2 hex digits, upper case)
+			- optional # prefixes 0x or 0X
+		%d	- decimal int
+		%c	- char
+		%s	- string
+	Note: width specification not supported
+**************************************************************************/
+void vsprintf(char *buffer, const char *fmt, va_list args)
+{
+	char *p;
+
+	for ( ; *fmt != '\0'; ++fmt) {
+		if (*fmt != '%') {
+			if (buffer)
+				*buffer++ = *fmt;
+			else
+				putchar(*fmt);
+			continue;
+		}
+		if (*++fmt == 's') {
+			for (p = va_arg(args, char *); *p != '\0'; p++)
+				if (buffer)
+					*buffer++ = *p;
+				else
+					putchar(*p);
+		} else {	/* Length of item is bounded */
+			char tmp[40], *q = tmp;
+			int shift = INT_SHIFT;
+
+			if (*fmt == 'L') {
+				shift = LONG_LONG_SHIFT;
+				fmt++;
+			} else if (*fmt == 'l') {
+				shift = LONG_SHIFT;
+				fmt++;
+			} else if (*fmt == 'h') {
+				shift = SHRT_SHIFT;
+				fmt++;
+				if (*fmt == 'h') {
+					shift = CHAR_SHIFT;
+					fmt++;
+				}
+			}
+
+			/*
+			 * Before each format q points to tmp buffer
+			 * After each format q points past end of item
+			 */
+			if ((*fmt | 0x20) == 'x') {
+				/* With x86 gcc, sizeof(long) == sizeof(int) */
+				unsigned long long h;
+				int ncase;
+
+				if (shift > LONG_SHIFT)
+					h = va_arg(args, unsigned long long);
+				else if (shift > INT_SHIFT)
+					h = va_arg(args, unsigned long);
+				else
+					h = va_arg(args, unsigned int);
+
+				ncase = (*fmt & 0x20);
+				for ( ; shift >= 0; shift -= 4)
+					*q++ = "0123456789ABCDEF"[(h >> shift) & 0xF] | ncase;
+			} else if (*fmt == 'd') {
+				char *r;
+				long i;
+
+				if (shift > LONG_SHIFT)
+					i = va_arg(args, long long);
+				else if (shift > INT_SHIFT)
+					i = va_arg(args, long);
+				else
+					i = va_arg(args, int);
+
+				if (i < 0) {
+					*q++ = '-';
+					i = -i;
+				}
+				p = q;		/* save beginning of digits */
+				do {
+					*q++ = '0' + (i % 10);
+					i /= 10;
+				} while (i);
+				/* reverse digits, stop in middle */
+				r = q;		/* don't alter q */
+				while (--r > p) {
+					i = *r;
+					*r = *p;
+					*p++ = i;
+				}
+			} else if (*fmt == 'c')
+				*q++ = va_arg(args, int);
+			else
+				*q++ = *fmt;
+			/* now output the saved string */
+			for (p = tmp; p < q; ++p)
+				if (buffer)
+					*buffer++ = *p;
+				else
+					putchar(*p);
+		}
+	}
+	if (buffer)
+		*buffer = '\0';
+}
+
+void sprintf(char *buffer, const char *fmt, ...)
+{
+	va_list args;
+
+	va_start(args, fmt);
+	vsprintf(buffer, fmt, args);
+	va_end(args);
+}
+
+void printf(const char *fmt, ...)
+{
+	va_list args;
+
+	va_start(args, fmt);
+	vsprintf(0, fmt, args);
+	va_end(args);
+}
diff --git a/arch/powerpc/purgatory/purgatory-ppc64.c b/arch/powerpc/purgatory/purgatory-ppc64.c
new file mode 100644
index 000000000000..2e9545bcdcb4
--- /dev/null
+++ b/arch/powerpc/purgatory/purgatory-ppc64.c
@@ -0,0 +1,36 @@
+/*
+ * kexec: Linux boots Linux
+ *
+ * Created by: Mohan Kumar M (mohan@...ibm.com)
+ *
+ * Copyright (C) IBM Corporation, 2005. All rights reserved
+ *
+ * Code taken from kexec-tools.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation (version 2 of the License).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include "purgatory.h"
+
+unsigned long stack __section(".data");
+unsigned long dt_offset __section(".data");
+unsigned long my_toc __section(".data");
+unsigned long kernel __section(".data");
+int debug __section(".data");
+unsigned long opal_base __section(".data");
+unsigned long opal_entry __section(".data");
+
+void setup_arch(void)
+{
+}
+
+void post_verification_setup_arch(void)
+{
+}
diff --git a/arch/powerpc/purgatory/purgatory.c b/arch/powerpc/purgatory/purgatory.c
new file mode 100644
index 000000000000..179f2da2b56f
--- /dev/null
+++ b/arch/powerpc/purgatory/purgatory.c
@@ -0,0 +1,62 @@
+/*
+ * Code taken from kexec-tools.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation (version 2 of the License).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include "purgatory.h"
+#include "sha256.h"
+#include "../boot/string.h"
+#include "kexec-sha256.h"
+
+struct kexec_sha_region sha_regions[SHA256_REGIONS] __section(".data");
+u8 sha256_digest[SHA256_DIGEST_SIZE] __section(".data");
+
+int verify_sha256_digest(void)
+{
+	struct kexec_sha_region *ptr, *end;
+	u8 digest[SHA256_DIGEST_SIZE];
+	size_t i;
+	struct sha256_state sctx;
+
+	sha256_init(&sctx);
+	end = &sha_regions[sizeof(sha_regions)/sizeof(sha_regions[0])];
+	for (ptr = sha_regions; ptr < end; ptr++)
+		sha256_update(&sctx, (uint8_t *)(ptr->start), ptr->len);
+	sha256_final(&sctx, digest);
+
+	if (memcmp(digest, sha256_digest, sizeof(digest)) != 0) {
+		printf("sha256 digests do not match :(\n");
+		printf("       digest: ");
+		for (i = 0; i < sizeof(digest); i++)
+			printf("%hhx ", digest[i]);
+		printf("\n");
+
+		printf("sha256_digest: ");
+		for (i = 0; i < sizeof(sha256_digest); i++)
+			printf("%hhx ", sha256_digest[i]);
+
+		printf("\n");
+		return 1;
+	}
+	return 0;
+}
+
+void purgatory(void)
+{
+	printf("I'm in purgatory\n");
+	setup_arch();
+	if (verify_sha256_digest()) {
+		/* loop forever */
+		for (;;)
+			;
+	}
+	post_verification_setup_arch();
+}
diff --git a/arch/powerpc/purgatory/purgatory.h b/arch/powerpc/purgatory/purgatory.h
new file mode 100644
index 000000000000..fde99e8b5043
--- /dev/null
+++ b/arch/powerpc/purgatory/purgatory.h
@@ -0,0 +1,14 @@
+#ifndef PURGATORY_H
+#define PURGATORY_H
+
+#include <linux/compiler.h>
+
+extern int debug;
+
+void putchar(int ch);
+void sprintf(char *buffer, const char *fmt, ...) __printf(2, 3);
+void printf(const char *fmt, ...) __printf(1, 2);
+void setup_arch(void);
+void post_verification_setup_arch(void);
+
+#endif /* PURGATORY_H */
diff --git a/arch/powerpc/purgatory/sha256.c b/arch/powerpc/purgatory/sha256.c
new file mode 100644
index 000000000000..6abee1877d56
--- /dev/null
+++ b/arch/powerpc/purgatory/sha256.c
@@ -0,0 +1,6 @@
+#include "../boot/string.h"
+
+/* Avoid including x86's boot/string.h in sha256.c. */
+#define BOOT_STRING_H
+
+#include "../../x86/purgatory/sha256.c"
diff --git a/arch/powerpc/purgatory/sha256.h b/arch/powerpc/purgatory/sha256.h
new file mode 100644
index 000000000000..72818f3a207e
--- /dev/null
+++ b/arch/powerpc/purgatory/sha256.h
@@ -0,0 +1 @@
+#include "../../x86/purgatory/sha256.h"
diff --git a/arch/powerpc/purgatory/string.S b/arch/powerpc/purgatory/string.S
new file mode 100644
index 000000000000..19d92e4e7554
--- /dev/null
+++ b/arch/powerpc/purgatory/string.S
@@ -0,0 +1,2 @@
+#include "ppc64_asm.h"
+#include "../boot/string.S"
diff --git a/arch/powerpc/purgatory/v2wrap.S b/arch/powerpc/purgatory/v2wrap.S
new file mode 100644
index 000000000000..c9a981c39a78
--- /dev/null
+++ b/arch/powerpc/purgatory/v2wrap.S
@@ -0,0 +1,134 @@
+#
+#  kexec: Linux boots Linux
+#
+#  Copyright (C) 2004 - 2005, Milton D Miller II, IBM Corporation
+#  Copyright (C) 2006, Mohan Kumar M (mohan@...ibm.com), IBM Corporation
+#
+# Code taken from kexec-tools.
+#
+#  This program is free software; you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation (version 2 of the License).
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+
+#include "ppc64_asm.h"
+
+# v2wrap.S
+# a wrapper to call purgatory code to backup first
+# 32kB of first kernel into the backup region
+# reserved by kexec-tools.
+# Invokes ppc64 kernel with the expected arguments
+# of kernel(device-tree, phys-offset, 0)
+
+#
+# calling convention:
+#   r3 = physical number of this cpu (all cpus)
+#   r4 = address of this chunk (master only)
+# master enters at purgatory_start (aka first byte of this chunk)
+# slaves (additional cpus), if any, enter a copy of the
+# first 0x100 bytes of this code relocated to 0x0
+#
+# in other words,
+#   a copy of the first 0x100 bytes of this code is copied to 0
+#   and the slaves are sent to address 0x60
+#   with r3 = their physical cpu number.
+
+#define LOADADDR(rn,name) \
+	lis     rn,name##@...hest;      \
+	ori     rn,rn,name##@...her;    \
+	rldicr  rn,rn,32,31;            \
+	oris    rn,rn,name##@h;         \
+	ori     rn,rn,name##@l
+
+	.machine ppc64
+	.align 8
+	.globl purgatory_start
+purgatory_start:	b	master
+	.org purgatory_start + 0x5c     # ABI: possible run_at_load flag at 0x5c
+	.globl run_at_load
+run_at_load:
+	.long 0
+	.size run_at_load, . - run_at_load
+	.org purgatory_start + 0x60     # ABI: slaves start at 60 with r3=phys
+slave:	b $
+	.org purgatory_start + 0x100    # ABI: end of copied region
+	.size purgatory_start, . - purgatory_start
+
+#
+# The above 0x100 bytes at purgatory_start are replaced with the
+# code from the kernel (or next stage) by kexec/arch/ppc64/kexec-elf-ppc64.c
+#
+
+master:
+	or	1,1,1		# low priority to let other threads catchup
+	isync
+	mr      17,3            # save cpu id to r17
+	mr      15,4            # save physical address in reg15
+
+	LOADADDR(6,my_toc)
+	ld      2,0(6)          #setup toc
+
+	LOADADDR(6,stack)
+	ld      1,0(6)          #setup stack
+
+	subi    1,1,112
+	bl      DOTSYM(purgatory)
+	nop
+
+	or	3,3,3		# ok now to high priority, lets boot
+	lis	6,0x1
+	mtctr	6		# delay a bit for slaves to catch up
+83:	bdnz	83b		# before we overwrite 0-100 again
+
+	LOADADDR(16, dt_offset)
+	ld      3,0(16)         # load device-tree address
+	mr      16,3            # save dt address in reg16
+#ifdef __BIG_ENDIAN__
+	lwz     6,20(3)         # fetch version number
+#else
+	li	4,20
+	lwbrx	6,3,4		# fetch BE version number
+#endif
+	cmpwi   0,6,2           # v2 ?
+	blt     80f
+#ifdef __BIG_ENDIAN__
+	stw     17,28(3)        # save my cpu number as boot_cpu_phys
+#else
+	li	4,28
+	stwbrx	17,3,4		# Store my cpu as BE value
+#endif
+80:
+	LOADADDR(6,opal_base)	# For OPAL early debug
+	ld      8,0(6)          # load the OPAL base address in r8
+	LOADADDR(6,opal_entry)	# For OPAL early debug
+	ld      9,0(6)          # load the OPAL entry address in r9
+	LOADADDR(6,kernel)
+	ld      4,0(6)          # load the kernel address
+	LOADADDR(6,run_at_load) # the load flag
+	lwz	7,0(6)		# possibly patched by kexec-elf-ppc64
+	stw	7,0x5c(4)	# and patch it into the kernel
+	mr      3,16            # restore dt address
+
+	mfmsr	5
+	andi.	10,5,1		# test MSR_LE
+	bne	little_endian
+
+	li	5,0		# r5 will be 0 for kernel
+	mtctr	4		# prepare branch to
+	bctr			# start kernel
+
+little_endian:			# book3s-only
+	mtsrr0	4		# prepare branch to
+
+	clrrdi	5,5,1		# clear MSR_LE
+	mtsrr1	5
+
+	li	5,0		# r5 will be 0 for kernel
+
+				# skip cache flush, do we care?
+
+	rfid			# update MSR and start kernel
-- 
2.7.4

Powered by blists - more mailing lists