MIPS: Add support for GZIP / BZIP2 / LZMA compressed kernel images

This patch helps to generate smaller kernel images for linux-MIPS,

Here is the effect when using lzma:

$ ls -sh vmlinux
7.1M vmlinux
$ ls -sh vmlinuz
1.5M 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 dozen 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@googlemail.com>
Tested-by: Alexander Clouter <alex@digriz.org.uk>
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 14 insertions, 0 deletions

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index fd7620f025fa..f6f3b990d837 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -22,6 +22,7 @@ choice
 
 config MACH_ALCHEMY
         bool "Alchemy processor based machines"
+        select SYS_SUPPORTS_ZBOOT
 
 config AR7
         bool "Texas Instruments AR7"
@@ -36,6 +37,7 @@ 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
@@ -192,6 +194,7 @@ 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.
 
@@ -233,6 +236,7 @@ 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