On Tue, 2009-10-13 at 00:05 +0800, Wu Zangjin wrote:
> From: Wu Zhangjin <wuzhangjin@xxxxxxxxx>
>
> This patch will help to generate smaller kernel images for linux-MIPS,
>
> Here is the effect when using lzma:
>
> $ ls -sh vmlinux
> 7.1M vmlinux
> $ ls -sh arch/mips/boot/compressed/vmlinuz
> 1.5M arch/mips/boot/compressed/vmlinuz
>
The above message is out-of-date, the path of vmlinuz have been changed
to the root directory linux, it should be:
$ ls -sh vmlinux (original)
6.0M vmlinux
$ ls -sh vmlinuz (lzma)
1.2M vmlinuz
$ ls -sh vmlinuz (bzip2)
1.5M vmlinuz
$ ls -sh vmlinuz (gzip)
1.6M vmlinuz
> Have tested the 32bit kernel on Qemu/Malta and 64bit kernel on FuLoong
> Mini PC. both of them work well. and also, tested by Alexander Clouter
> on an AR7 based Linksys WAG54Gv2, and by Manuel Lauss on an Alchemy
> board.
>
> This -v2 version incorporate the feedback from Ralf, and add the
> following changes:
>
> 1. add .ecoff, .bin, .erec format support
> 2. only enable it and the debug source code for the machines we tested
> 3. a dozens of fixups and cleanups
>
> and if you want to enable it for your board, please try to select
> SYS_SUPPORTS_ZBOOT for it, and if the board have an 16550 compatible
> uart, you can select SYS_SUPPORTS_ZBOOT_UART16550 directly. and then
> sending the relative patches to Ralf.
>
> Tested-by: Manuel Lauss <manuel.lauss@xxxxxxxxxxxxxx>
> Signed-off-by: Alexander Clouter <alex@xxxxxxxxxxxxx>
> Signed-off-by: Wu Zhangjin <wuzhangjin@xxxxxxxxx>
> ---
> arch/mips/Kconfig | 14 +++
> arch/mips/Makefile | 31 ++++++-
> arch/mips/boot/compressed/Makefile | 100 +++++++++++++++++++++
> arch/mips/boot/compressed/dbg.c | 37 ++++++++
> arch/mips/boot/compressed/decompress.c | 126 +++++++++++++++++++++++++++
> arch/mips/boot/compressed/dummy.c | 4 +
> arch/mips/boot/compressed/head.S | 55 ++++++++++++
> arch/mips/boot/compressed/ld.script | 150 ++++++++++++++++++++++++++++++++
> arch/mips/boot/compressed/uart-16550.c | 43 +++++++++
> 9 files changed, 557 insertions(+), 3 deletions(-)
> create mode 100644 arch/mips/boot/compressed/Makefile
> create mode 100644 arch/mips/boot/compressed/dbg.c
> create mode 100644 arch/mips/boot/compressed/decompress.c
> create mode 100644 arch/mips/boot/compressed/dummy.c
> create mode 100644 arch/mips/boot/compressed/head.S
> create mode 100644 arch/mips/boot/compressed/ld.script
> create mode 100644 arch/mips/boot/compressed/uart-16550.c
>
> diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
> index 9da6a52..96bb02d 100644
> --- a/arch/mips/Kconfig
> +++ b/arch/mips/Kconfig
> @@ -21,6 +21,7 @@ choice
>
> config MACH_ALCHEMY
> bool "Alchemy processor based machines"
> + select SYS_SUPPORTS_ZBOOT
>
> config AR7
> bool "Texas Instruments AR7"
> @@ -35,6 +36,7 @@ config AR7
> select SYS_HAS_EARLY_PRINTK
> select SYS_SUPPORTS_32BIT_KERNEL
> select SYS_SUPPORTS_LITTLE_ENDIAN
> + select SYS_SUPPORTS_ZBOOT_UART16550
> select GENERIC_GPIO
> select GCD
> select VLYNQ
> @@ -191,6 +193,7 @@ config LASAT
>
> config MACH_LOONGSON
> bool "Loongson family of machines"
> + select SYS_SUPPORTS_ZBOOT_UART16550
> help
> This enables the support of Loongson family of machines.
>
> @@ -232,6 +235,7 @@ config MIPS_MALTA
> select SYS_SUPPORTS_MIPS_CMP
> select SYS_SUPPORTS_MULTITHREADING
> select SYS_SUPPORTS_SMARTMIPS
> + select SYS_SUPPORTS_ZBOOT
> help
> This enables support for the MIPS Technologies Malta evaluation
> board.
> @@ -1294,6 +1298,16 @@ config CPU_CAVIUM_OCTEON
>
> endchoice
>
> +config SYS_SUPPORTS_ZBOOT
> + bool
> + select HAVE_KERNEL_GZIP
> + select HAVE_KERNEL_BZIP2
> + select HAVE_KERNEL_LZMA
> +
> +config SYS_SUPPORTS_ZBOOT_UART16550
> + bool
> + select SYS_SUPPORTS_ZBOOT
> +
> config CPU_LOONGSON2
> bool
> select CPU_SUPPORTS_32BIT_KERNEL
> diff --git a/arch/mips/Makefile b/arch/mips/Makefile
> index d45e596..ccd713d 100644
> --- a/arch/mips/Makefile
> +++ b/arch/mips/Makefile
> @@ -69,6 +69,7 @@ endif
>
> all-$(CONFIG_BOOT_ELF32) := $(vmlinux-32)
> all-$(CONFIG_BOOT_ELF64) := $(vmlinux-64)
> +all-$(CONFIG_SYS_SUPPORTS_ZBOOT)+= vmlinuz
>
> #
> # GCC uses -G 0 -mabicalls -fpic as default. We don't want PIC in the kernel
> @@ -336,7 +337,7 @@ load-$(CONFIG_LEMOTE_YEELOONG2F) +=0xffffffff80200000
> core-$(CONFIG_MIPS_MALTA) += arch/mips/mti-malta/
> cflags-$(CONFIG_MIPS_MALTA) += -I$(srctree)/arch/mips/include/asm/mach-malta
> load-$(CONFIG_MIPS_MALTA) += 0xffffffff80100000
> -all-$(CONFIG_MIPS_MALTA) := vmlinux.bin
> +all-$(CONFIG_MIPS_MALTA) := vmlinuz.bin
>
> #
> # MIPS SIM
> @@ -586,7 +587,7 @@ load-$(CONFIG_SNI_RM) += 0xffffffff80600000
> else
> load-$(CONFIG_SNI_RM) += 0xffffffff80030000
> endif
> -all-$(CONFIG_SNI_RM) := vmlinux.ecoff
> +all-$(CONFIG_SNI_RM) := vmlinuz.ecoff
>
> #
> # Common TXx9
> @@ -704,9 +705,23 @@ vmlinux.64: vmlinux
> $(OBJCOPY) -O $(64bit-bfd) $(OBJCOPYFLAGS) $< $@
>
> makeboot =$(Q)$(MAKE) $(build)=arch/mips/boot VMLINUX=$(vmlinux-32) $(1)
> +makezboot =$(Q)$(MAKE) $(build)=arch/mips/boot/compressed \
> + VMLINUX_LOAD_ADDRESS=$(load-y) 32bit-bfd=$(32bit-bfd) $(1)
>
> all: $(all-y)
>
> +vmlinuz: vmlinux
> + +@$(call makezboot,$@)
> +
> +vmlinuz.bin: vmlinux
> + +@$(call makezboot,$@)
> +
> +vmlinuz.ecoff: vmlinux
> + +@$(call makezboot,$@)
> +
> +vmlinuz.srec: vmlinux
> + +@$(call makezboot,$@)
> +
> vmlinux.bin: $(vmlinux-32)
> +@$(call makeboot,$@)
>
> @@ -731,11 +746,13 @@ endif
>
> install:
> $(Q)install -D -m 755 vmlinux $(INSTALL_PATH)/vmlinux-$(KERNELRELEASE)
> + $(Q)install -D -m 755 vmlinuz $(INSTALL_PATH)/vmlinuz-$(KERNELRELEASE)
> $(Q)install -D -m 644 .config $(INSTALL_PATH)/config-$(KERNELRELEASE)
> $(Q)install -D -m 644 System.map $(INSTALL_PATH)/System.map-$(KERNELRELEASE)
>
> archclean:
> @$(MAKE) $(clean)=arch/mips/boot
> + @$(MAKE) $(clean)=arch/mips/boot/compressed
> @$(MAKE) $(clean)=arch/mips/lasat
>
> define archhelp
> @@ -743,10 +760,18 @@ define archhelp
> echo ' vmlinux.ecoff - ECOFF boot image'
> echo ' vmlinux.bin - Raw binary boot image'
> echo ' vmlinux.srec - SREC boot image'
> + echo ' vmlinuz - Compressed boot(zboot) image'
> + echo ' vmlinuz.ecoff - ECOFF zboot image'
> + echo ' vmlinuz.bin - Raw binary zboot image'
> + echo ' vmlinuz.srec - SREC zboot image'
> echo
> echo ' These will be default as apropriate for a configured platform.'
> endef
>
> CLEAN_FILES += vmlinux.32 \
> vmlinux.64 \
> - vmlinux.ecoff
> + vmlinux.ecoff \
> + vmlinuz \
> + vmlinuz.ecoff \
> + vmlinuz.bin \
> + vmlinuz.srec
> diff --git a/arch/mips/boot/compressed/Makefile b/arch/mips/boot/compressed/Makefile
> new file mode 100644
> index 0000000..140bd9b
> --- /dev/null
> +++ b/arch/mips/boot/compressed/Makefile
> @@ -0,0 +1,100 @@
> +#
> +# This file is subject to the terms and conditions of the GNU General Public
> +# License.
> +#
> +# Adapted for MIPS Pete Popov, Dan Malek
> +#
> +# Copyright (C) 1994 by Linus Torvalds
> +# Adapted for PowerPC by Gary Thomas
> +# modified by Cort (cort@xxxxxxxxxx)
> +#
> +# Copyright (C) 2009 Lemote Inc. & DSLab, Lanzhou University
> +# Author: Wu Zhangjin <wuzj@xxxxxxxxxx>
> +#
> +
> +# compressed kernel load addr: VMLINUZ_LOAD_ADDRESS > VMLINUX_LOAD_ADDRESS + VMLINUX_SIZE
> +VMLINUX_SIZE := $(shell wc -c $(objtree)/$(KBUILD_IMAGE) 2>/dev/null | cut -d' ' -f1)
> +VMLINUX_SIZE := $(shell [ -n "$(VMLINUX_SIZE)" ] && echo $$(($(VMLINUX_SIZE) + (65536 - $(VMLINUX_SIZE) % 65536))))
> +VMLINUZ_LOAD_ADDRESS := 0x$(shell [ -n "$(VMLINUX_SIZE)" ] && printf %x $$(($(VMLINUX_LOAD_ADDRESS) + $(VMLINUX_SIZE))))
> +
> +# set the default size of the mallocing area for decompressing
> +BOOT_HEAP_SIZE := 0x400000
> +
> +KBUILD_CFLAGS := $(LINUXINCLUDE) $(KBUILD_CFLAGS) -D__KERNEL__ \
> + -DBOOT_HEAP_SIZE=$(BOOT_HEAP_SIZE) -D"VMLINUX_LOAD_ADDRESS_ULL=$(VMLINUX_LOAD_ADDRESS)ull" \
> +
> +KBUILD_AFLAGS := $(LINUXINCLUDE) $(KBUILD_AFLAGS) -D__ASSEMBLY__ \
> + -DKERNEL_ENTRY=0x$(shell $(NM) $(objtree)/$(KBUILD_IMAGE) 2>/dev/null | grep " kernel_entry" | cut -f1 -d \ ) \
> + -DBOOT_HEAP_SIZE=$(BOOT_HEAP_SIZE)
> +
> +obj-y := $(obj)/head.o $(obj)/decompress.o $(obj)/dbg.o
> +
> +obj-$(CONFIG_SYS_SUPPORTS_ZBOOT_UART16550) += $(obj)/uart-16550.o
> +
> +OBJCOPYFLAGS_vmlinux.bin := $(OBJCOPYFLAGS) -O binary -R .comment -S
> +$(obj)/vmlinux.bin: $(KBUILD_IMAGE)
> + $(call if_changed,objcopy)
> +
> +suffix_$(CONFIG_KERNEL_GZIP) = gz
> +suffix_$(CONFIG_KERNEL_BZIP2) = bz2
> +suffix_$(CONFIG_KERNEL_LZMA) = lzma
> +tool_$(CONFIG_KERNEL_GZIP) = gzip
> +tool_$(CONFIG_KERNEL_BZIP2) = bzip2
> +tool_$(CONFIG_KERNEL_LZMA) = lzma
> +$(obj)/vmlinux.$(suffix_y): $(obj)/vmlinux.bin
> + $(call if_changed,$(tool_y))
> + $(Q)rm -f $<
> +
> +$(obj)/piggy.o: $(obj)/vmlinux.$(suffix_y) $(obj)/dummy.o
> + $(Q)$(OBJCOPY) $(OBJCOPYFLAGS) \
> + --add-section=.image=$< \
> + --set-section-flags=.image=contents,alloc,load,readonly,data \
> + $(obj)/dummy.o $@
> + $(Q)rm -f $<
> +
> +LDFLAGS_vmlinuz := $(LDFLAGS) -Ttext $(VMLINUZ_LOAD_ADDRESS) -T
> +vmlinuz: $(src)/ld.script $(obj-y) $(obj)/piggy.o
> + $(call if_changed,ld)
> + $(Q)$(OBJCOPY) $(OBJCOPYFLAGS) -R .comment -R .stab -R .stabstr -R .initrd -R .sysmap $@
> + $(Q)rm -f $(obj)/piggy.o
> +
> +#
> +# Some DECstations need all possible sections of an ECOFF executable
> +#
> +ifdef CONFIG_MACH_DECSTATION
> + E2EFLAGS = -a
> +else
> + E2EFLAGS =
> +endif
> +
> +# elf2ecoff can only handle 32bit image
> +
> +ifdef CONFIG_32BIT
> + VMLINUZ = vmlinuz
> +else
> + VMLINUZ = vmlinuz.32
> +endif
> +
> +vmlinuz.32: vmlinuz
> + $(Q)$(OBJCOPY) -O $(32bit-bfd) $(OBJCOPYFLAGS) $< $@
> +
> +vmlinuz.ecoff: $(obj)/../elf2ecoff $(VMLINUZ)
> + $(Q)$(obj)/../elf2ecoff $(VMLINUZ) vmlinuz.ecoff $(E2EFLAGS)
> +
> +$(obj)/../elf2ecoff: $(src)/../elf2ecoff.c
> + $(Q)$(HOSTCC) -o $@ $^
> +
> +drop-sections = .reginfo .mdebug .comment .note .pdr .options .MIPS.options
> +strip-flags = $(addprefix --remove-section=,$(drop-sections))
> +
> +OBJCOPYFLAGS_vmlinuz.bin := $(OBJCOPYFLAGS) -O binary $(strip-flags)
> +vmlinuz.bin: vmlinuz
> + $(call if_changed,objcopy)
> +
> +OBJCOPYFLAGS_vmlinuz.srec := $(OBJCOPYFLAGS) -S -O srec $(strip-flags)
> +vmlinuz.srec: vmlinuz
> + $(call if_changed,objcopy)
> +
> +clean:
> +clean-files += *.o \
> + vmlinu*
> diff --git a/arch/mips/boot/compressed/dbg.c b/arch/mips/boot/compressed/dbg.c
> new file mode 100644
> index 0000000..ff4dc7a
> --- /dev/null
> +++ b/arch/mips/boot/compressed/dbg.c
> @@ -0,0 +1,37 @@
> +/*
> + * MIPS-specific debug support for pre-boot environment
> + *
> + * NOTE: putc() is board specific, if your board have a 16550 compatible uart,
> + * please select SYS_SUPPORTS_ZBOOT_UART16550 for your machine. othewise, you
> + * need to implement your own putc().
> + */
> +
> +#include <linux/init.h>
> +#include <linux/types.h>
> +
> +void __attribute__ ((weak)) putc(char c)
> +{
> +}
> +
> +void puts(const char *s)
> +{
> + char c;
> + while ((c = *s++) != '\0') {
> + putc(c);
> + if (c == '\n')
> + putc('\r');
> + }
> +}
> +
> +void puthex(unsigned long long val)
> +{
> +
> + unsigned char buf[10];
> + int i;
> + for (i = 7; i >= 0; i--) {
> + buf[i] = "0123456789ABCDEF"[val & 0x0F];
> + val >>= 4;
> + }
> + buf[8] = '\0';
> + puts(buf);
> +}
> diff --git a/arch/mips/boot/compressed/decompress.c b/arch/mips/boot/compressed/decompress.c
> new file mode 100644
> index 0000000..67330c2
> --- /dev/null
> +++ b/arch/mips/boot/compressed/decompress.c
> @@ -0,0 +1,126 @@
> +/*
> + * Misc. bootloader code for many machines.
> + *
> + * Copyright 2001 MontaVista Software Inc.
> + * Author: Matt Porter <mporter@xxxxxxxxxx> Derived from
> + * arch/ppc/boot/prep/misc.c
> + *
> + * Copyright (C) 2009 Lemote, Inc. & Institute of Computing Technology
> + * Author: Wu Zhangjin <wuzj@xxxxxxxxxx>
> + *
> + * 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 <linux/types.h>
> +#include <linux/kernel.h>
> +
> +#include <asm/addrspace.h>
> +
> +/* These two variables specify the free mem region
> + * that can be used for temporary malloc area
> + */
> +unsigned long free_mem_ptr;
> +unsigned long free_mem_end_ptr;
> +char *zimage_start;
> +
> +/* The linker tells us where the image is. */
> +extern unsigned char __image_begin, __image_end;
> +extern unsigned char __ramdisk_begin, __ramdisk_end;
> +unsigned long initrd_size;
> +
> +/* debug interfaces */
> +extern void puts(const char *s);
> +extern void puthex(unsigned long long val);
> +
> +void error(char *x)
> +{
> + puts("\n\n");
> + puts(x);
> + puts("\n\n -- System halted");
> +
> + while (1)
> + ; /* Halt */
> +}
> +
> +/* activate the code for pre-boot environment */
> +#define STATIC static
> +
> +#ifdef CONFIG_KERNEL_GZIP
> +void *memcpy(void *dest, const void *src, size_t n)
> +{
> + int i;
> + const char *s = src;
> + char *d = dest;
> +
> + for (i = 0; i < n; i++)
> + d[i] = s[i];
> + return dest;
> +}
> +#include "../../../../lib/decompress_inflate.c"
> +#endif
> +
> +#ifdef CONFIG_KERNEL_BZIP2
> +void *memset(void *s, int c, size_t n)
> +{
> + int i;
> + char *ss = s;
> +
> + for (i = 0; i < n; i++)
> + ss[i] = c;
> + return s;
> +}
> +#include "../../../../lib/decompress_bunzip2.c"
> +#endif
> +
> +#ifdef CONFIG_KERNEL_LZMA
> +#include "../../../../lib/decompress_unlzma.c"
> +#endif
> +
> +void decompress_kernel(unsigned long boot_heap_start)
> +{
> + int zimage_size;
> +
> + /*
> + * We link ourself to an arbitrary low address. When we run, we
> + * relocate outself to that address. __image_beign points to
> + * the part of the image where the zImage is. -- Tom
> + */
> + zimage_start = (char *)(unsigned long)(&__image_begin);
> + zimage_size = (unsigned long)(&__image_end) -
> + (unsigned long)(&__image_begin);
> +
> + /*
> + * The zImage and initrd will be between start and _end, so they've
> + * already been moved once. We're good to go now. -- Tom
> + */
> + puts("zimage at: ");
> + puthex((unsigned long)zimage_start);
> + puts(" ");
> + puthex((unsigned long)(zimage_size + zimage_start));
> + puts("\n");
> +
> + if (initrd_size) {
> + puts("initrd at: ");
> + puthex((unsigned long)(&__ramdisk_begin));
> + puts(" ");
> + puthex((unsigned long)(&__ramdisk_end));
> + puts("\n");
> + }
> +
> + /* this area are prepared for mallocing when decompressing */
> + free_mem_ptr = boot_heap_start;
> + free_mem_end_ptr = boot_heap_start + BOOT_HEAP_SIZE;
> +
> + /* Display standard Linux/MIPS boot prompt for kernel args */
> + puts("Uncompressing Linux at load address ");
> + puthex(VMLINUX_LOAD_ADDRESS_ULL);
> + puts("\n");
> + /* Decompress the kernel with according algorithm */
> + decompress(zimage_start, zimage_size, 0, 0,
> + (void *)VMLINUX_LOAD_ADDRESS_ULL, 0, error);
> + /* FIXME: is there a need to flush cache here? */
> + puts("Now, booting the kernel...\n");
> +}
> diff --git a/arch/mips/boot/compressed/dummy.c b/arch/mips/boot/compressed/dummy.c
> new file mode 100644
> index 0000000..31dbf45
> --- /dev/null
> +++ b/arch/mips/boot/compressed/dummy.c
> @@ -0,0 +1,4 @@
> +int main(void)
> +{
> + return 0;
> +}
> diff --git a/arch/mips/boot/compressed/head.S b/arch/mips/boot/compressed/head.S
> new file mode 100644
> index 0000000..e23f25e
> --- /dev/null
> +++ b/arch/mips/boot/compressed/head.S
> @@ -0,0 +1,55 @@
> +/*
> + * This file is subject to the terms and conditions of the GNU General Public
> + * License. See the file "COPYING" in the main directory of this archive
> + * for more details.
> + *
> + * Copyright (C) 1994, 1995 Waldorf Electronics
> + * Written by Ralf Baechle and Andreas Busse
> + * Copyright (C) 1995 - 1999 Ralf Baechle
> + * Copyright (C) 1996 Paul M. Antoine
> + * Modified for DECStation and hence R3000 support by Paul M. Antoine
> + * Further modifications by David S. Miller and Harald Koerfgen
> + * Copyright (C) 1999 Silicon Graphics, Inc.
> + */
> +
> +#include <asm/asm.h>
> +#include <asm/regdef.h>
> +
> + .set noreorder
> + .cprestore
> + LEAF(start)
> +start:
> + /* Save boot rom start args */
> + move s0, a0
> + move s1, a1
> + move s2, a2
> + move s3, a3
> +
> + /* Clear BSS */
> + PTR_LA a0, _edata
> + PTR_LA a2, _end
> +1: sw zero, 0(a0)
> + bne a2, a0, 1b
> + addu a0, 4
> +
> + PTR_LA a0, (.heap) /* heap address */
> + PTR_LA sp, (.stack + 8192) /* stack address */
> +
> + PTR_LA ra, 2f
> + PTR_LA k0, decompress_kernel
> + jr k0
> + nop
> +2:
> + move a0, s0
> + move a1, s1
> + move a2, s2
> + move a3, s3
> + PTR_LI k0, KERNEL_ENTRY
> + jr k0
> + nop
> +3:
> + b 3b
> + END(start)
> +
> + .comm .heap,BOOT_HEAP_SIZE,4
> + .comm .stack,4096*2,4
> diff --git a/arch/mips/boot/compressed/ld.script b/arch/mips/boot/compressed/ld.script
> new file mode 100644
> index 0000000..29e9f4c
> --- /dev/null
> +++ b/arch/mips/boot/compressed/ld.script
> @@ -0,0 +1,150 @@
> +OUTPUT_ARCH(mips)
> +ENTRY(start)
> +SECTIONS
> +{
> + /* Read-only sections, merged into text segment: */
> + .init : { *(.init) } =0
> + .text :
> + {
> + _ftext = . ;
> + *(.text)
> + *(.rodata)
> + *(.rodata1)
> + /* .gnu.warning sections are handled specially by elf32.em. */
> + *(.gnu.warning)
> + } =0
> + .kstrtab : { *(.kstrtab) }
> +
> + . = ALIGN(16); /* Exception table */
> + __start___ex_table = .;
> + __ex_table : { *(__ex_table) }
> + __stop___ex_table = .;
> +
> + __start___dbe_table = .; /* Exception table for data bus errors */
> + __dbe_table : { *(__dbe_table) }
> + __stop___dbe_table = .;
> +
> + __start___ksymtab = .; /* Kernel symbol table */
> + __ksymtab : { *(__ksymtab) }
> + __stop___ksymtab = .;
> +
> + _etext = .;
> +
> + . = ALIGN(8192);
> + .data.init_task : { *(.data.init_task) }
> +
> + /* Startup code */
> + . = ALIGN(4096);
> + __init_begin = .;
> + .text.init : { *(.text.init) }
> + .data.init : { *(.data.init) }
> + . = ALIGN(16);
> + __setup_start = .;
> + .setup.init : { *(.setup.init) }
> + __setup_end = .;
> + __initcall_start = .;
> + .initcall.init : { *(.initcall.init) }
> + __initcall_end = .;
> + . = ALIGN(4096); /* Align double page for init_task_union */
> + __init_end = .;
> +
> + . = ALIGN(4096);
> + .data.page_aligned : { *(.data.idt) }
> +
> + . = ALIGN(32);
> + .data.cacheline_aligned : { *(.data.cacheline_aligned) }
> +
> + .fini : { *(.fini) } =0
> + .reginfo : { *(.reginfo) }
> + /* Adjust the address for the data segment. We want to adjust up to
> + the same address within the page on the next page up. It would
> + be more correct to do this:
> + . = .;
> + The current expression does not correctly handle the case of a
> + text segment ending precisely at the end of a page; it causes the
> + data segment to skip a page. The above expression does not have
> + this problem, but it will currently (2/95) cause BFD to allocate
> + a single segment, combining both text and data, for this case.
> + This will prevent the text segment from being shared among
> + multiple executions of the program; I think that is more
> + important than losing a page of the virtual address space (note
> + that no actual memory is lost; the page which is skipped can not
> + be referenced). */
> + . = .;
> + .data :
> + {
> + _fdata = . ;
> + *(.data)
> +
> + /* Put the compressed image here, so bss is on the end. */
> + __image_begin = .;
> + *(.image)
> + __image_end = .;
> + /* Align the initial ramdisk image (INITRD) on page boundaries. */
> + . = ALIGN(4096);
> + __ramdisk_begin = .;
> + *(.initrd)
> + __ramdisk_end = .;
> + . = ALIGN(4096);
> +
> + CONSTRUCTORS
> + }
> + .data1 : { *(.data1) }
> + _gp = . + 0x8000;
> + .lit8 : { *(.lit8) }
> + .lit4 : { *(.lit4) }
> + .ctors : { *(.ctors) }
> + .dtors : { *(.dtors) }
> + .got : { *(.got.plt) *(.got) }
> + .dynamic : { *(.dynamic) }
> + /* We want the small data sections together, so single-instruction offsets
> + can access them all, and initialized data all before uninitialized, so
> + we can shorten the on-disk segment size. */
> + .sdata : { *(.sdata) }
> + . = ALIGN(4);
> + _edata = .;
> + PROVIDE (edata = .);
> +
> + __bss_start = .;
> + _fbss = .;
> + .sbss : { *(.sbss) *(.scommon) }
> + .bss :
> + {
> + *(.dynbss)
> + *(.bss)
> + *(COMMON)
> + . = ALIGN(4);
> + _end = . ;
> + PROVIDE (end = .);
> + }
> +
> + /* Sections to be discarded */
> + /DISCARD/ :
> + {
> + *(.text.exit)
> + *(.data.exit)
> + *(.exitcall.exit)
> + }
> +
> + /* This is the MIPS specific mdebug section. */
> + .mdebug : { *(.mdebug) }
> + /* These are needed for ELF backends which have not yet been
> + converted to the new style linker. */
> + .stab 0 : { *(.stab) }
> + .stabstr 0 : { *(.stabstr) }
> + /* DWARF debug sections.
> + Symbols in the .debug DWARF section are relative to the beginning of the
> + section so we begin .debug at 0. It's not clear yet what needs to happen
> + for the others. */
> + .debug 0 : { *(.debug) }
> + .debug_srcinfo 0 : { *(.debug_srcinfo) }
> + .debug_aranges 0 : { *(.debug_aranges) }
> + .debug_pubnames 0 : { *(.debug_pubnames) }
> + .debug_sfnames 0 : { *(.debug_sfnames) }
> + .line 0 : { *(.line) }
> + /* These must appear regardless of . */
> + .gptab.sdata : { *(.gptab.data) *(.gptab.sdata) }
> + .gptab.sbss : { *(.gptab.bss) *(.gptab.sbss) }
> + .comment : { *(.comment) }
> + .note : { *(.note) }
> +}
> diff --git a/arch/mips/boot/compressed/uart-16550.c b/arch/mips/boot/compressed/uart-16550.c
> new file mode 100644
> index 0000000..c9caaf4
> --- /dev/null
> +++ b/arch/mips/boot/compressed/uart-16550.c
> @@ -0,0 +1,43 @@
> +/*
> + * 16550 compatible uart based serial debug support for zboot
> + */
> +
> +#include <linux/types.h>
> +#include <linux/serial_reg.h>
> +#include <linux/init.h>
> +
> +#include <asm/addrspace.h>
> +
> +#if defined(CONFIG_MACH_LOONGSON) || defined(CONFIG_MIPS_MALTA)
> +#define UART_BASE 0x1fd003f8
> +#define PORT(offset) (CKSEG1ADDR(UART_BASE) + (offset))
> +#endif
> +
> +#ifdef CONFIG_AR7
> +#include <ar7.h>
> +#define PORT(offset) (CKSEG1ADDR(AR7_REGS_UART0) + (4 * offset))
> +#endif
> +
> +#ifndef PORT
> +#error please define the serial port address for your own machine
> +#endif
> +
> +static inline unsigned int serial_in(int offset)
> +{
> + return *((char *)PORT(offset));
> +}
> +
> +static inline void serial_out(int offset, int value)
> +{
> + *((char *)PORT(offset)) = value;
> +}
> +
> +void putc(char c)
> +{
> + int timeout = 1024;
> +
> + while (((serial_in(UART_LSR) & UART_LSR_THRE) == 0) && (timeout-- > 0))
> + ;
> +
> + serial_out(UART_TX, c);
> +}
