Contents of /trunk/kernel26-magellan-server/patches-2.6.25-r5/0157-2.6.25-acpi-dsdt-initrd-0.9a.patch
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Wed Sep 10 21:27:27 2008 UTC (16 years, 1 month ago) by niro
File size: 9961 byte(s)
Wed Sep 10 21:27:27 2008 UTC (16 years, 1 month ago) by niro
File size: 9961 byte(s)
2.6.25-magellan-r5: - updated to linux-2.6.25.17
1 | From de31945e20bc0bd255d0264c5d97a6b24906b30a Mon Sep 17 00:00:00 2001 |
2 | From: Eric Piel <piel@localhost.(none)> |
3 | Date: Wed, 19 Mar 2008 23:00:04 +0100 |
4 | Subject: [PATCH 1/1] ACPI: initramfs DSDT override support |
5 | |
6 | Permits to load of DSDT (the main ACPI table) from initramfs. In case this |
7 | option is selected, the initramfs is parsed at ACPI initialization (very early |
8 | boot time) to look for a file DSDT.aml . This aims at allowing users to |
9 | override the DSDT without recompiling the kernel. This is done by adding a new |
10 | feature to the initramfs parser so that one specific file can be directly |
11 | copied into memory. |
12 | |
13 | This is derived from the patch v0.8 from http://gaugusch.at/kernel.shtml but |
14 | with kernel inclusion in mind: some clean-up's in the documentation, default |
15 | set to No, a kernel parameter to disable it at runtime, and most important, a |
16 | different approach for reading the initramfs which avoids using the filesystem |
17 | infrastructure. |
18 | |
19 | It also contains a fix for compilation on non-ACPI platforms provided by Rene Rebe. |
20 | |
21 | Signed-off-by: Eric Piel <eric.piel@tremplin-utc.net> |
22 | Signed-off-by: Thomas Renninger <trenn@suse.de> |
23 | Signed-off-by: Len Brown <len.brown@intel.com> |
24 | --- |
25 | Documentation/acpi/dsdt-override.txt | 12 ++++- |
26 | Documentation/acpi/initramfs-add-dsdt.sh | 43 +++++++++++++++++ |
27 | Documentation/kernel-parameters.txt | 3 + |
28 | drivers/acpi/Kconfig | 11 ++++ |
29 | drivers/acpi/osl.c | 24 ++++++++++ |
30 | init/initramfs.c | 76 ++++++++++++++++++++++++++++++ |
31 | 6 files changed, 167 insertions(+), 2 deletions(-) |
32 | create mode 100644 Documentation/acpi/initramfs-add-dsdt.sh |
33 | |
34 | diff --git a/Documentation/acpi/dsdt-override.txt b/Documentation/acpi/dsdt-override.txt |
35 | index febbb1b..5008f25 100644 |
36 | --- a/Documentation/acpi/dsdt-override.txt |
37 | +++ b/Documentation/acpi/dsdt-override.txt |
38 | @@ -1,7 +1,15 @@ |
39 | -Linux supports a method of overriding the BIOS DSDT: |
40 | +Linux supports two methods of overriding the BIOS DSDT: |
41 | |
42 | CONFIG_ACPI_CUSTOM_DSDT builds the image into the kernel. |
43 | |
44 | -When to use this method is described in detail on the |
45 | +CONFIG_ACPI_CUSTOM_DSDT_INITRD adds the image to the initrd. |
46 | + |
47 | +When to use these methods is described in detail on the |
48 | Linux/ACPI home page: |
49 | http://www.lesswatts.org/projects/acpi/overridingDSDT.php |
50 | + |
51 | +Note that if both options are used, the DSDT supplied |
52 | +by the INITRD method takes precedence. |
53 | + |
54 | +Documentation/initramfs-add-dsdt.sh is provided for convenience |
55 | +for use with the CONFIG_ACPI_CUSTOM_DSDT_INITRD method. |
56 | diff --git a/Documentation/acpi/initramfs-add-dsdt.sh b/Documentation/acpi/initramfs-add-dsdt.sh |
57 | new file mode 100644 |
58 | index 0000000..17ef6e8 |
59 | --- /dev/null |
60 | +++ b/Documentation/acpi/initramfs-add-dsdt.sh |
61 | @@ -0,0 +1,43 @@ |
62 | +#!/bin/bash |
63 | +# Adds a DSDT file to the initrd (if it's an initramfs) |
64 | +# first argument is the name of archive |
65 | +# second argument is the name of the file to add |
66 | +# The file will be copied as /DSDT.aml |
67 | + |
68 | +# 20060126: fix "Premature end of file" with some old cpio (Roland Robic) |
69 | +# 20060205: this time it should really work |
70 | + |
71 | +# check the arguments |
72 | +if [ $# -ne 2 ]; then |
73 | + program_name=$(basename $0) |
74 | + echo "\ |
75 | +$program_name: too few arguments |
76 | +Usage: $program_name initrd-name.img DSDT-to-add.aml |
77 | +Adds a DSDT file to an initrd (in initramfs format) |
78 | + |
79 | + initrd-name.img: filename of the initrd in initramfs format |
80 | + DSDT-to-add.aml: filename of the DSDT file to add |
81 | + " 1>&2 |
82 | + exit 1 |
83 | +fi |
84 | + |
85 | +# we should check it's an initramfs |
86 | + |
87 | +tempcpio=$(mktemp -d) |
88 | +# cleanup on exit, hangup, interrupt, quit, termination |
89 | +trap 'rm -rf $tempcpio' 0 1 2 3 15 |
90 | + |
91 | +# extract the archive |
92 | +gunzip -c "$1" > "$tempcpio"/initramfs.cpio || exit 1 |
93 | + |
94 | +# copy the DSDT file at the root of the directory so that we can call it "/DSDT.aml" |
95 | +cp -f "$2" "$tempcpio"/DSDT.aml |
96 | + |
97 | +# add the file |
98 | +cd "$tempcpio" |
99 | +(echo DSDT.aml | cpio --quiet -H newc -o -A -O "$tempcpio"/initramfs.cpio) || exit 1 |
100 | +cd "$OLDPWD" |
101 | + |
102 | +# re-compress the archive |
103 | +gzip -c "$tempcpio"/initramfs.cpio > "$1" |
104 | + |
105 | diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt |
106 | index 622f784..49318b9 100644 |
107 | --- a/Documentation/kernel-parameters.txt |
108 | +++ b/Documentation/kernel-parameters.txt |
109 | @@ -177,6 +177,9 @@ and is between 256 and 4096 characters. It is defined in the file |
110 | |
111 | acpi_no_auto_ssdt [HW,ACPI] Disable automatic loading of SSDT |
112 | |
113 | + acpi_no_initrd_override [KNL,ACPI] |
114 | + Disable loading custom ACPI tables from the initramfs |
115 | + |
116 | acpi_os_name= [HW,ACPI] Tell ACPI BIOS the name of the OS |
117 | Format: To spoof as Windows 98: ="Microsoft Windows" |
118 | |
119 | diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig |
120 | index b4f5e85..fbcaa06 100644 |
121 | --- a/drivers/acpi/Kconfig |
122 | +++ b/drivers/acpi/Kconfig |
123 | @@ -300,6 +300,17 @@ config ACPI_CUSTOM_DSDT |
124 | bool |
125 | default ACPI_CUSTOM_DSDT_FILE != "" |
126 | |
127 | +config ACPI_CUSTOM_DSDT_INITRD |
128 | + bool "Read Custom DSDT from initramfs" |
129 | + depends on BLK_DEV_INITRD |
130 | + default n |
131 | + help |
132 | + This option supports a custom DSDT by optionally loading it from initrd. |
133 | + See Documentation/acpi/dsdt-override.txt |
134 | + |
135 | + If you are not using this feature now, but may use it later, |
136 | + it is safe to say Y here. |
137 | + |
138 | config ACPI_BLACKLIST_YEAR |
139 | int "Disable ACPI for systems before Jan 1st this year" if X86_32 |
140 | default 0 |
141 | diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c |
142 | index a697fb6..8fa630f 100644 |
143 | --- a/drivers/acpi/osl.c |
144 | +++ b/drivers/acpi/osl.c |
145 | @@ -91,6 +91,11 @@ static DEFINE_SPINLOCK(acpi_res_lock); |
146 | #define OSI_STRING_LENGTH_MAX 64 /* arbitrary */ |
147 | static char osi_additional_string[OSI_STRING_LENGTH_MAX]; |
148 | |
149 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD |
150 | +static int acpi_no_initrd_override; |
151 | +extern struct acpi_table_header *acpi_find_dsdt_initrd(void); |
152 | +#endif |
153 | + |
154 | /* |
155 | * "Ode to _OSI(Linux)" |
156 | * |
157 | @@ -333,6 +338,16 @@ acpi_os_table_override(struct acpi_table_header * existing_table, |
158 | if (strncmp(existing_table->signature, "DSDT", 4) == 0) |
159 | *new_table = (struct acpi_table_header *)AmlCode; |
160 | #endif |
161 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD |
162 | + if ((strncmp(existing_table->signature, "DSDT", 4) == 0) && |
163 | + !acpi_no_initrd_override) { |
164 | + struct acpi_table_header *initrd_table; |
165 | + |
166 | + initrd_table = acpi_find_dsdt_initrd(); |
167 | + if (initrd_table) |
168 | + *new_table = initrd_table; |
169 | + } |
170 | +#endif |
171 | if (*new_table != NULL) { |
172 | printk(KERN_WARNING PREFIX "Override [%4.4s-%8.8s], " |
173 | "this is unsafe: tainting kernel\n", |
174 | @@ -343,6 +358,15 @@ acpi_os_table_override(struct acpi_table_header * existing_table, |
175 | return AE_OK; |
176 | } |
177 | |
178 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD |
179 | +static int __init acpi_no_initrd_override_setup(char *s) |
180 | +{ |
181 | + acpi_no_initrd_override = 1; |
182 | + return 1; |
183 | +} |
184 | +__setup("acpi_no_initrd_override", acpi_no_initrd_override_setup); |
185 | +#endif |
186 | + |
187 | static irqreturn_t acpi_irq(int irq, void *dev_id) |
188 | { |
189 | u32 handled; |
190 | diff --git a/init/initramfs.c b/init/initramfs.c |
191 | index d53fee8..495380c 100644 |
192 | --- a/init/initramfs.c |
193 | +++ b/init/initramfs.c |
194 | @@ -6,6 +6,9 @@ |
195 | #include <linux/delay.h> |
196 | #include <linux/string.h> |
197 | #include <linux/syscalls.h> |
198 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD |
199 | +#include <acpi/acpi.h> |
200 | +#endif |
201 | |
202 | static __initdata char *message; |
203 | static void __init error(char *x) |
204 | @@ -90,6 +91,12 @@ static __initdata unsigned long body_len, name_len; |
205 | static __initdata uid_t uid; |
206 | static __initdata gid_t gid; |
207 | static __initdata unsigned rdev; |
208 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD |
209 | +static __initdata char *file_looked_for; |
210 | +static __initdata struct acpi_table_header *file_mem; |
211 | +#else |
212 | +const char *file_looked_for = NULL; |
213 | +#endif |
214 | |
215 | static void __init parse_header(char *s) |
216 | { |
217 | @@ -123,6 +130,7 @@ static __initdata enum state { |
218 | SkipIt, |
219 | GotName, |
220 | CopyFile, |
221 | + CopyFileMem, |
222 | GotSymlink, |
223 | Reset |
224 | } state, next_state; |
225 | @@ -267,6 +275,9 @@ static int __init do_name(void) |
226 | free_hash(); |
227 | return 0; |
228 | } |
229 | + if (file_looked_for && S_ISREG(mode) && |
230 | + (strcmp(collected, file_looked_for) == 0)) |
231 | + state = CopyFileMem; |
232 | if (dry_run) |
233 | return 0; |
234 | clean_path(collected, mode); |
235 | @@ -299,6 +310,40 @@ static int __init do_name(void) |
236 | return 0; |
237 | } |
238 | |
239 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD |
240 | +static int __init do_copy_mem(void) |
241 | +{ |
242 | + static void *file_current; /* current position in the memory */ |
243 | + if (file_mem == NULL) { |
244 | + if (body_len < 4) { /* check especially against empty files */ |
245 | + error("file is less than 4 bytes"); |
246 | + return 1; |
247 | + } |
248 | + file_mem = kmalloc(body_len, GFP_ATOMIC); |
249 | + if (!file_mem) { |
250 | + error("failed to allocate enough memory"); |
251 | + return 1; |
252 | + } |
253 | + file_current = file_mem; |
254 | + } |
255 | + if (count >= body_len) { |
256 | + memcpy(file_current, victim, body_len); |
257 | + eat(body_len); |
258 | + file_looked_for = NULL; /* don't find files with same name */ |
259 | + state = SkipIt; |
260 | + return 0; |
261 | + } else { |
262 | + memcpy(file_current, victim, count); |
263 | + file_current += count; |
264 | + body_len -= count; |
265 | + eat(count); |
266 | + return 1; |
267 | + } |
268 | +} |
269 | +#else |
270 | +#define do_copy_mem NULL |
271 | +#endif |
272 | + |
273 | static int __init do_copy(void) |
274 | { |
275 | if (count >= body_len) { |
276 | @@ -333,6 +378,7 @@ static __initdata int (*actions[])(void) = { |
277 | [SkipIt] = do_skip, |
278 | [GotName] = do_name, |
279 | [CopyFile] = do_copy, |
280 | + [CopyFileMem] = do_copy_mem, |
281 | [GotSymlink] = do_symlink, |
282 | [Reset] = do_reset, |
283 | }; |
284 | @@ -578,3 +624,31 @@ static int __init populate_rootfs(void) |
285 | return 0; |
286 | } |
287 | rootfs_initcall(populate_rootfs); |
288 | + |
289 | +#ifdef CONFIG_ACPI_CUSTOM_DSDT_INITRD |
290 | +struct acpi_table_header *acpi_find_dsdt_initrd(void) |
291 | +{ |
292 | + char *err, *ramfs_dsdt_name = "DSDT.aml"; |
293 | + |
294 | + printk(KERN_INFO "ACPI: Checking initramfs for custom DSDT\n"); |
295 | + file_mem = NULL; |
296 | + file_looked_for = ramfs_dsdt_name; |
297 | + err = unpack_to_rootfs((char *)initrd_start, |
298 | + initrd_end - initrd_start, 1); |
299 | + file_looked_for = NULL; |
300 | + |
301 | + if (err) { |
302 | + /* |
303 | + * Even if reading the DSDT file was successful, |
304 | + * we give up if the initramfs cannot be entirely read. |
305 | + */ |
306 | + kfree(file_mem); |
307 | + printk(KERN_ERR "ACPI: Aborded because %s.\n", err); |
308 | + return NULL; |
309 | + } |
310 | + if (file_mem) |
311 | + printk(KERN_INFO "ACPI: Found DSDT in %s.\n", ramfs_dsdt_name); |
312 | + |
313 | + return file_mem; |
314 | +} |
315 | +#endif |
316 | -- |
317 | 1.5.4.3 |
318 |