diff options
Diffstat (limited to 'patches/acpi-dsdt-initrd-v0.9c-2.6.26.patch')
-rw-r--r-- | patches/acpi-dsdt-initrd-v0.9c-2.6.26.patch | 325 |
1 files changed, 325 insertions, 0 deletions
diff --git a/patches/acpi-dsdt-initrd-v0.9c-2.6.26.patch b/patches/acpi-dsdt-initrd-v0.9c-2.6.26.patch new file mode 100644 index 0000000..1be70f8 --- /dev/null +++ b/patches/acpi-dsdt-initrd-v0.9c-2.6.26.patch @@ -0,0 +1,325 @@ +Date: Wed, 19 Mar 2008 23:00:04 +0100 +Subject: [PATCH] ACPI: initramfs DSDT override support + +Permits to load of DSDT (the main ACPI table) from initramfs. In case this +option is selected, the initramfs is parsed at ACPI initialization (very early +boot time) to look for a file called "DSDT.aml". This aims at allowing users to +override the DSDT without recompiling the kernel. + +Version 0.9 uses a different approach for reading the initramfs which avoids +using the filesystem infrastructure. It leverages the initramfs unpack code to find +and unpack the DSDT directly into the memory. + +v0.9a: Fix compilation on non-ACPI platforms by René Rebe <rene@exactcode.de> +v0.9b: Declare more functions __init by Jan Beulich <jbeulich@novell.com> +v0.9c: Allow root to be / instead of nothing, bug reported by Robert Hampovcan + +Signed-off-by: Eric Piel <eric.piel@tremplin-utc.net> +--- + Documentation/acpi/dsdt-override.txt | 12 +++- + Documentation/acpi/initramfs-add-dsdt.sh | 43 ++++++++++++++ + Documentation/kernel-parameters.txt | 3 + + drivers/acpi/Kconfig | 11 ++++ + drivers/acpi/osl.c | 24 ++++++++ + init/initramfs.c | 89 ++++++++++++++++++++++++++++++ + 6 files changed, 180 insertions(+), 2 deletions(-) + create mode 100644 Documentation/acpi/initramfs-add-dsdt.sh + +diff --git a/Documentation/acpi/dsdt-override.txt b/Documentation/acpi/dsdt-override.txt +index febbb1b..5008f25 100644 +--- a/Documentation/acpi/dsdt-override.txt ++++ b/Documentation/acpi/dsdt-override.txt +@@ -1,7 +1,15 @@ +-Linux supports a method of overriding the BIOS DSDT: ++Linux supports two methods of overriding the BIOS DSDT: + + CONFIG_ACPI_CUSTOM_DSDT builds the image into the kernel. + +-When to use this method is described in detail on the ++CONFIG_ACPI_CUSTOM_DSDT_INITRD adds the image to the initrd. ++ ++When to use these methods is described in detail on the + Linux/ACPI home page: + http://www.lesswatts.org/projects/acpi/overridingDSDT.php ++ ++Note that if both options are used, the DSDT supplied ++by the INITRD method takes precedence. ++ ++Documentation/initramfs-add-dsdt.sh is provided for convenience ++for use with the CONFIG_ACPI_CUSTOM_DSDT_INITRD method. +diff --git a/Documentation/acpi/initramfs-add-dsdt.sh b/Documentation/acpi/initramfs-add-dsdt.sh +new file mode 100644 +index 0000000..17ef6e8 +--- /dev/null ++++ b/Documentation/acpi/initramfs-add-dsdt.sh +@@ -0,0 +1,43 @@ ++#!/bin/bash ++# Adds a DSDT file to the initrd (if it's an initramfs) ++# first argument is the name of archive ++# second argument is the name of the file to add ++# The file will be copied as /DSDT.aml ++ ++# 20060126: fix "Premature end of file" with some old cpio (Roland Robic) ++# 20060205: this time it should really work ++ ++# check the arguments ++if [ $# -ne 2 ]; then ++ program_name=$(basename $0) ++ echo "\ ++$program_name: too few arguments ++Usage: $program_name initrd-name.img DSDT-to-add.aml ++Adds a DSDT file to an initrd (in initramfs format) ++ ++ initrd-name.img: filename of the initrd in initramfs format ++ DSDT-to-add.aml: filename of the DSDT file to add ++ " 1>&2 ++ exit 1 ++fi ++ ++# we should check it's an initramfs ++ ++tempcpio=$(mktemp -d) ++# cleanup on exit, hangup, interrupt, quit, termination ++trap 'rm -rf $tempcpio' 0 1 2 3 15 ++ ++# extract the archive ++gunzip -c "$1" > "$tempcpio"/initramfs.cpio || exit 1 ++ ++# copy the DSDT file at the root of the directory so that we can call it "/DSDT.aml" ++cp -f "$2" "$tempcpio"/DSDT.aml ++ ++# add the file ++cd "$tempcpio" ++(echo DSDT.aml | cpio --quiet -H newc -o -A -O "$tempcpio"/initramfs.cpio) || exit 1 ++cd "$OLDPWD" ++ ++# re-compress the archive ++gzip -c "$tempcpio"/initramfs.cpio > "$1" ++ +diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt +index e07c432..6849df2 100644 +--- a/Documentation/kernel-parameters.txt ++++ b/Documentation/kernel-parameters.txt +@@ -172,6 +172,9 @@ and is between 256 and 4096 characters. It is defined in the file + + acpi_no_auto_ssdt [HW,ACPI] Disable automatic loading of SSDT + ++ acpi_no_initrd_override [KNL,ACPI] ++ Disable loading custom ACPI tables from the initramfs ++ + acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS + Format: To spoof as Windows 98: ="Microsoft Windows" + +diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig +index c52fca8..8df213e 100644 +--- a/drivers/acpi/Kconfig ++++ b/drivers/acpi/Kconfig +@@ -303,6 +303,17 @@ config ACPI_CUSTOM_DSDT + bool + default ACPI_CUSTOM_DSDT_FILE != "" + ++config ACPI_CUSTOM_DSDT_INITRD ++ bool "Read Custom DSDT from initramfs" ++ depends on BLK_DEV_INITRD ++ default n ++ help ++ This option supports a custom DSDT by optionally loading it from initrd. ++ See Documentation/acpi/dsdt-override.txt ++ ++ If you are not using this feature now, but may use it later, ++ it is safe to say Y here. ++ + config ACPI_BLACKLIST_YEAR + int "Disable ACPI for systems before Jan 1st this year" if X86_32 + default 0 +diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c +index 235a138..c75f285 100644 +--- a/drivers/acpi/osl.c ++++ b/drivers/acpi/osl.c +@@ -96,6 +96,11 @@ static DEFINE_SPINLOCK(acpi_res_lock); + #define OSI_STRING_LENGTH_MAX 64 /* arbitrary */ + static char osi_additional_string[OSI_STRING_LENGTH_MAX]; + ++#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD ++static __initdata int acpi_no_initrd_override; ++extern struct acpi_table_header *acpi_find_dsdt_initrd(void); ++#endif ++ + /* + * "Ode to _OSI(Linux)" + * +@@ -338,6 +343,16 @@ acpi_os_table_override(struct acpi_table_header * existing_table, + if (strncmp(existing_table->signature, "DSDT", 4) == 0) + *new_table = (struct acpi_table_header *)AmlCode; + #endif ++#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD ++ if ((strncmp(existing_table->signature, "DSDT", 4) == 0) && ++ !acpi_no_initrd_override) { ++ struct acpi_table_header *initrd_table; ++ ++ initrd_table = acpi_find_dsdt_initrd(); ++ if (initrd_table) ++ *new_table = initrd_table; ++ } ++#endif + if (*new_table != NULL) { + printk(KERN_WARNING PREFIX "Override [%4.4s-%8.8s], " + "this is unsafe: tainting kernel\n", +@@ -348,6 +363,15 @@ acpi_os_table_override(struct acpi_table_header * existing_table, + return AE_OK; + } + ++#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD ++static int __init acpi_no_initrd_override_setup(char *s) ++{ ++ acpi_no_initrd_override = 1; ++ return 1; ++} ++__setup("acpi_no_initrd_override", acpi_no_initrd_override_setup); ++#endif ++ + static irqreturn_t acpi_irq(int irq, void *dev_id) + { + u32 handled; +diff --git a/init/initramfs.c b/init/initramfs.c +index 8eeeccb..84f9a01 100644 +--- a/init/initramfs.c ++++ b/init/initramfs.c +@@ -6,6 +6,9 @@ + #include <linux/string.h> + #include <linux/syscalls.h> + #include <linux/utime.h> ++#ifdef ACPI_CONFIG ++#include <acpi/acpi.h> ++#endif + + static __initdata char *message; + static void __init error(char *x) +@@ -90,6 +93,12 @@ static __initdata unsigned long body_len, name_len; + static __initdata uid_t uid; + static __initdata gid_t gid; + static __initdata unsigned rdev; ++#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD ++static __initdata char *file_looked_for; ++static __initdata struct acpi_table_header *file_mem; ++#else ++const char *file_looked_for = NULL; ++#endif + + static void __init parse_header(char *s) + { +@@ -123,6 +132,7 @@ static __initdata enum state { + SkipIt, + GotName, + CopyFile, ++ CopyFileMem, + GotSymlink, + Reset + } state, next_state; +@@ -259,6 +269,54 @@ static void __init clean_path(char *path, mode_t mode) + + static __initdata int wfd; + ++#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD ++static __init int is_file_looked_for(char *filename) ++{ ++ char *tmp_collected = collected; ++ if (file_looked_for == NULL) ++ return 0; ++ if (!S_ISREG(mode)) ++ return 0; ++ /* remove the leading / */ ++ while (*tmp_collected == '/') ++ tmp_collected++; ++ return (strcmp(tmp_collected, file_looked_for) == 0); ++} ++ ++static int __init do_copy_mem(void) ++{ ++ static void *file_current; /* current position in the memory */ ++ if (file_mem == NULL) { ++ if (body_len < 4) { /* check especially against empty files */ ++ error("file is less than 4 bytes"); ++ return 1; ++ } ++ file_mem = kmalloc(body_len, GFP_ATOMIC); ++ if (!file_mem) { ++ error("failed to allocate enough memory"); ++ return 1; ++ } ++ file_current = file_mem; ++ } ++ if (count >= body_len) { ++ memcpy(file_current, victim, body_len); ++ eat(body_len); ++ file_looked_for = NULL; /* don't find files with same name */ ++ state = SkipIt; ++ return 0; ++ } else { ++ memcpy(file_current, victim, count); ++ file_current += count; ++ body_len -= count; ++ eat(count); ++ return 1; ++ } ++} ++#else ++static inline int is_file_looked_for(char *filename) {return 0;} ++#define do_copy_mem NULL /* because it is used as a pointer */ ++#endif ++ + static int __init do_name(void) + { + state = SkipIt; +@@ -267,6 +325,8 @@ static int __init do_name(void) + free_hash(); + return 0; + } ++ if (is_file_looked_for(file_looked_for)) ++ state = CopyFileMem; + if (dry_run) + return 0; + clean_path(collected, mode); +@@ -333,6 +393,7 @@ static __initdata int (*actions[])(void) = { + [SkipIt] = do_skip, + [GotName] = do_name, + [CopyFile] = do_copy, ++ [CopyFileMem] = do_copy_mem, + [GotSymlink] = do_symlink, + [Reset] = do_reset, + }; +@@ -578,3 +639,31 @@ static int __init populate_rootfs(void) + return 0; + } + rootfs_initcall(populate_rootfs); ++ ++#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD ++struct __init acpi_table_header *acpi_find_dsdt_initrd(void) ++{ ++ char *err, *ramfs_dsdt_name = "DSDT.aml"; ++ ++ printk(KERN_INFO "ACPI: Checking initramfs for custom DSDT\n"); ++ file_mem = NULL; ++ file_looked_for = ramfs_dsdt_name; ++ err = unpack_to_rootfs((char *)initrd_start, ++ initrd_end - initrd_start, 1); ++ file_looked_for = NULL; ++ ++ if (err) { ++ /* ++ * Even if reading the DSDT file was successful, ++ * we give up if the initramfs cannot be entirely read. ++ */ ++ kfree(file_mem); ++ printk(KERN_ERR "ACPI: Aborded because %s.\n", err); ++ return NULL; ++ } ++ if (file_mem) ++ printk(KERN_INFO "ACPI: Found DSDT in %s.\n", ramfs_dsdt_name); ++ ++ return file_mem; ++} ++#endif +-- +1.5.6.4 + |