Add pre-bootloader (pbl) image support

This allows for creating a pre-bootloader binary for
 - nand boot
 - mmc boot
 - compressed image

The pbl will be incharge of the lowlevel init if needed.
The barebox will skip it.

Import string functions from linux 3.4 (arch/arm/boot/compressed/string.c) and
implement a dummy panic.

For now on introduce dummy zbarebox* targets and c code that will contain later
the decompressor. This only implemeted on ARM.

This patch is based on Sascha Hauer <s.hauer@pengutronix.de>
Add compressed image support patch

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>

10 files changed, 277 insertions, 40 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 08c742bfb3..7932afc131 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -4,6 +4,7 @@ config ARM
 	select HAS_MODULES
 	select HAVE_CONFIGURABLE_MEMORY_LAYOUT
 	select HAVE_CONFIGURABLE_TEXT_BASE
+	select HAVE_PBL_IMAGE
 	default y
 
 config ARM_AMBA
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index 1b60261bc8..0ea050ebed 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -197,6 +197,13 @@ ifeq ($(CONFIG_ARCH_DAVINCI),y)
 KBUILD_IMAGE := barebox.ubl
 endif
 
+pbl := arch/arm/pbl
+zbarebox.S zbarebox.bin zbarebox: barebox.bin
+	$(Q)$(MAKE) $(build)=$(pbl) $(pbl)/$@
+
+archclean:
+	$(MAKE) $(clean)=$(pbl)
+
 all: $(KBUILD_IMAGE)
 
 archprepare: maketools
diff --git a/arch/arm/cpu/Makefile b/arch/arm/cpu/Makefile
index 93a34a9ff1..78d300dba8 100644
--- a/arch/arm/cpu/Makefile
+++ b/arch/arm/cpu/Makefile
@@ -1,7 +1,7 @@
 obj-y += cpu.o
 obj-$(CONFIG_ARM_EXCEPTIONS) += exceptions.o
 obj-$(CONFIG_ARM_EXCEPTIONS) += interrupts.o
-obj-y += start.o
+obj-y += start.o start-reset.o
 
 #
 # Any variants can be called as start-armxyz.S
@@ -15,3 +15,4 @@ obj-$(CONFIG_CPU_32v6) += cache-armv6.o
 obj-$(CONFIG_CPU_32v7) += cache-armv7.o
 obj-$(CONFIG_CACHE_L2X0) += cache-l2x0.o
 
+pbl-y += start-pbl.o start-reset.o
diff --git a/arch/arm/cpu/start-pbl.c b/arch/arm/cpu/start-pbl.c
new file mode 100644
index 0000000000..28d6f34449
--- /dev/null
+++ b/arch/arm/cpu/start-pbl.c
@@ -0,0 +1,80 @@
+/*
+ * start-pbl.c
+ *
+ * Copyright (c) 2010-2012 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
+ * Copyright (c) 2012 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <common.h>
+#include <init.h>
+#include <asm/barebox-arm.h>
+#include <asm/barebox-arm-head.h>
+#include <asm-generic/memory_layout.h>
+#include <asm/sections.h>
+
+void __naked __section(.text_head_entry) pbl_start(void)
+{
+	barebox_arm_head();
+}
+
+void barebox_pbl(uint32_t offset)
+{
+}
+
+/*
+ * Board code can jump here by either returning from board_init_lowlevel
+ * or by calling this function directly.
+ */
+void __naked __section(.text_ll_return) board_init_lowlevel_return(void)
+{
+	uint32_t r, addr, offset;
+
+	/*
+	 * Get runtime address of this function. Do not
+	 * put any code above this.
+	 */
+	__asm__ __volatile__("1: adr %0, 1b":"=r"(addr));
+
+	/* Setup the stack */
+	r = STACK_BASE + STACK_SIZE - 16;
+	__asm__ __volatile__("mov sp, %0" : : "r"(r));
+
+	/* Get offset between linked address and runtime address */
+	offset = (uint32_t)__ll_return - addr;
+
+	/* relocate to link address if necessary */
+	if (offset)
+		memcpy((void *)_text, (void *)(_text - offset),
+				__bss_start - _text);
+
+	/* clear bss */
+	memset(__bss_start, 0, __bss_stop - __bss_start);
+
+	/* flush I-cache before jumping to the copied binary */
+	__asm__ __volatile__("mcr p15, 0, %0, c7, c5, 0" : : "r" (0));
+
+	r = (unsigned int)&barebox_pbl;
+	/* call barebox_uncompress with its absolute address */
+	__asm__ __volatile__(
+		"mov r0, %1\n"
+		"mov pc, %0\n"
+		:
+		: "r"(r), "r"(offset),
+		: "r0");
+}
diff --git a/arch/arm/cpu/start-reset.c b/arch/arm/cpu/start-reset.c
new file mode 100644
index 0000000000..e0df676274
--- /dev/null
+++ b/arch/arm/cpu/start-reset.c
@@ -0,0 +1,67 @@
+/*
+ * start-reset.c
+ *
+ * Copyright (c) 2010 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <common.h>
+#include <init.h>
+#include <asm/system.h>
+#include <asm/barebox-arm.h>
+#include <asm/sections.h>
+
+/*
+ * The actual reset vector. This code is position independent and usually
+ * does not run at the address it's linked at.
+ */
+void __naked __bare_init reset(void)
+{
+	uint32_t r;
+
+	/* set the cpu to SVC32 mode */
+	__asm__ __volatile__("mrs %0, cpsr":"=r"(r));
+	r &= ~0x1f;
+	r |= 0xd3;
+	__asm__ __volatile__("msr cpsr, %0" : : "r"(r));
+
+#ifdef CONFIG_ARCH_HAS_LOWLEVEL_INIT
+	arch_init_lowlevel();
+#endif
+
+	/* disable MMU stuff and caches */
+	r = get_cr();
+	r &= ~(CR_M | CR_C | CR_B | CR_S | CR_R | CR_V);
+	r |= CR_I;
+
+#if __LINUX_ARM_ARCH__ >= 6
+	r |= CR_U;
+#else
+	r |= CR_A;
+#endif
+
+#ifdef __ARMEB__
+	r |= CR_B;
+#endif
+	set_cr(r);
+
+#ifdef CONFIG_MACH_DO_LOWLEVEL_INIT
+	board_init_lowlevel();
+#endif
+	board_init_lowlevel_return();
+}
diff --git a/arch/arm/cpu/start.c b/arch/arm/cpu/start.c
index 112403e33e..8365a7516f 100644
--- a/arch/arm/cpu/start.c
+++ b/arch/arm/cpu/start.c
@@ -24,53 +24,31 @@
 #include <init.h>
 #include <asm/barebox-arm.h>
 #include <asm/barebox-arm-head.h>
-#include <asm/system.h>
 #include <asm-generic/memory_layout.h>
 #include <asm/sections.h>
 
-void __naked __section(.text_entry) start(void)
-{
-	barebox_arm_head();
-}
-
+#ifdef CONFIG_PBL_IMAGE
 /*
- * The actual reset vector. This code is position independent and usually
- * does not run at the address it's linked at.
+ * First function in the pbl image. We get here from
+ * the pbl.
  */
-void __naked __bare_init reset(void)
+void __naked __section(.text_entry) start(void)
 {
-	uint32_t r;
+	u32 r;
 
-	/* set the cpu to SVC32 mode */
-	__asm__ __volatile__("mrs %0, cpsr":"=r"(r));
-	r &= ~0x1f;
-	r |= 0xd3;
-	__asm__ __volatile__("msr cpsr, %0" : : "r"(r));
-
-#ifdef CONFIG_ARCH_HAS_LOWLEVEL_INIT
-	arch_init_lowlevel();
-#endif
-
-	/* disable MMU stuff and caches */
-	r = get_cr();
-	r &= ~(CR_M | CR_C | CR_B | CR_S | CR_R | CR_V);
-	r |= CR_I;
+	/* Setup the stack */
+	r = STACK_BASE + STACK_SIZE - 16;
+	__asm__ __volatile__("mov sp, %0" : : "r"(r));
+	/* clear bss */
+	memset(__bss_start, 0, __bss_stop - __bss_start);
 
-#if __LINUX_ARM_ARCH__ >= 6
-	r |= CR_U;
+	start_barebox();
+}
 #else
-	r |= CR_A;
-#endif
-
-#ifdef __ARMEB__
-	r |= CR_B;
-#endif
-	set_cr(r);
 
-#ifdef CONFIG_MACH_DO_LOWLEVEL_INIT
-	board_init_lowlevel();
-#endif
-	board_init_lowlevel_return();
+void __naked __section(.text_entry) start(void)
+{
+	barebox_arm_head();
 }
 
 /*
@@ -109,4 +87,4 @@ void __naked __section(.text_ll_return) board_init_lowlevel_return(void)
 	r = (unsigned int)&start_barebox;
 	__asm__ __volatile__("mov pc, %0" : : "r"(r));
 }
-
+#endif
diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index 1eaf474911..9d0ff7a856 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -21,3 +21,7 @@ obj-$(CONFIG_ARM_OPTIMZED_STRING_FUNCTIONS)	+= memset.o
 obj-$(CONFIG_ARM_UNWIND) += unwind.o
 obj-$(CONFIG_MODULES) += module.o
 extra-y += barebox.lds
+
+pbl-y	+= lib1funcs.o
+pbl-y	+= ashldi3.o
+pbl-y	+= div0.o
diff --git a/arch/arm/lib/barebox.lds.S b/arch/arm/lib/barebox.lds.S
index e0bae70f4f..a69013f7f5 100644
--- a/arch/arm/lib/barebox.lds.S
+++ b/arch/arm/lib/barebox.lds.S
@@ -31,8 +31,9 @@ SECTIONS
 {
 	. = TEXT_BASE;
 
+#ifndef CONFIG_PBL_IMAGE
 	PRE_IMAGE
-
+#endif
 	. = ALIGN(4);
 	.text      :
 	{
diff --git a/arch/arm/pbl/Makefile b/arch/arm/pbl/Makefile
new file mode 100644
index 0000000000..9b364bb35a
--- /dev/null
+++ b/arch/arm/pbl/Makefile
@@ -0,0 +1,25 @@
+
+OBJCOPYFLAGS_zbarebox.bin = -O binary
+
+targets := zbarebox.lds zbarebox zbarebox.bin zbarebox.S
+
+$(obj)/zbarebox.bin:	$(obj)/zbarebox FORCE
+	$(call if_changed,objcopy)
+	$(call cmd,check_file_size,$(CONFIG_BAREBOX_MAX_IMAGE_SIZE))
+	@echo '  Barebox: $@ is ready'
+
+$(obj)/zbarebox.S: $(obj)/zbarebox FORCE
+	$(call if_changed,disasm)
+
+LDFLAGS_zbarebox	:= -Map zbarebox.map
+zbarebox-common := $(barebox-pbl-common)
+zbarebox-lds := $(obj)/zbarebox.lds
+
+quiet_cmd_zbarebox__ ?= LD      $@
+      cmd_zbarebox__ ?= $(LD) $(LDFLAGS) $(LDFLAGS_zbarebox) -o $@ \
+      -T $(zbarebox-lds)                                           \
+      --start-group $(zbarebox-common) --end-group                 \
+      $(filter-out $(zbarebox-lds) $(zbarebox-common) FORCE ,$^)
+
+$(obj)/zbarebox: $(zbarebox-lds) $(zbarebox-common) FORCE
+	$(call if_changed,zbarebox__)
diff --git a/arch/arm/pbl/zbarebox.lds.S b/arch/arm/pbl/zbarebox.lds.S
new file mode 100644
index 0000000000..b6e8028fd3
--- /dev/null
+++ b/arch/arm/pbl/zbarebox.lds.S
@@ -0,0 +1,73 @@
+/*
+ * (C) Copyright 2012 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ */
+
+#include <asm-generic/barebox.lds.h>
+#include <asm-generic/memory_layout.h>
+
+OUTPUT_FORMAT("elf32-littlearm", "elf32-littlearm", "elf32-littlearm")
+OUTPUT_ARCH(arm)
+ENTRY(pbl_start)
+SECTIONS
+{
+	. = HEAD_TEXT_BASE;
+
+	PRE_IMAGE
+
+	. = ALIGN(4);
+	.text      :
+	{
+		_stext = .;
+		_text = .;
+		*(.text_head_entry*)
+		__ll_return = .;
+		*(.text_ll_return*)
+		__bare_init_start = .;
+		*(.text_bare_init*)
+		__bare_init_end = .;
+		*(.text*)
+	}
+	BAREBOX_BARE_INIT_SIZE
+
+	. = ALIGN(4);
+	.rodata : { *(.rodata*) }
+
+	_etext = .;			/* End of text and rodata section */
+
+	. = ALIGN(4);
+	.data : { *(.data*) }
+
+	. = ALIGN(4);
+	__bss_start = .;
+	.bss : { *(.bss*) }
+	__bss_stop = .;
+	_end = .;
+
+	. = ALIGN(4);
+	__piggydata_start = .;
+	.piggydata : {
+		*(.piggydata)
+	}
+	__piggydata_end = .;
+
+	_barebox_image_size = __piggydata_end - HEAD_TEXT_BASE;
+}