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-rw-r--r--drivers/acpi/osl.c181
1 files changed, 136 insertions, 45 deletions
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index e3a673a0084..e96f3d933f6 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -77,11 +77,55 @@ static struct workqueue_struct *kacpi_notify_wq;
#define OSI_STRING_LENGTH_MAX 64 /* arbitrary */
static char osi_additional_string[OSI_STRING_LENGTH_MAX];
-static int osi_linux; /* disable _OSI(Linux) by default */
+/*
+ * "Ode to _OSI(Linux)"
+ *
+ * osi_linux -- Control response to BIOS _OSI(Linux) query.
+ *
+ * As Linux evolves, the features that it supports change.
+ * So an OSI string such as "Linux" is not specific enough
+ * to be useful across multiple versions of Linux. It
+ * doesn't identify any particular feature, interface,
+ * or even any particular version of Linux...
+ *
+ * Unfortunately, Linux-2.6.22 and earlier responded "yes"
+ * to a BIOS _OSI(Linux) query. When
+ * a reference mobile BIOS started using it, its use
+ * started to spread to many vendor platforms.
+ * As it is not supportable, we need to halt that spread.
+ *
+ * Today, most BIOS references to _OSI(Linux) are noise --
+ * they have no functional effect and are just dead code
+ * carried over from the reference BIOS.
+ *
+ * The next most common case is that _OSI(Linux) harms Linux,
+ * usually by causing the BIOS to follow paths that are
+ * not tested during Windows validation.
+ *
+ * Finally, there is a short list of platforms
+ * where OSI(Linux) benefits Linux.
+ *
+ * In Linux-2.6.23, OSI(Linux) is first disabled by default.
+ * DMI is used to disable the dmesg warning about OSI(Linux)
+ * on platforms where it is known to have no effect.
+ * But a dmesg warning remains for systems where
+ * we do not know if OSI(Linux) is good or bad for the system.
+ * DMI is also used to enable OSI(Linux) for the machines
+ * that are known to need it.
+ *
+ * BIOS writers should NOT query _OSI(Linux) on future systems.
+ * It will be ignored by default, and to get Linux to
+ * not ignore it will require a kernel source update to
+ * add a DMI entry, or a boot-time "acpi_osi=Linux" invocation.
+ */
+#define OSI_LINUX_ENABLE 0
-#ifdef CONFIG_DMI
-static struct __initdata dmi_system_id acpi_osl_dmi_table[];
-#endif
+struct osi_linux {
+ unsigned int enable:1;
+ unsigned int dmi:1;
+ unsigned int cmdline:1;
+ unsigned int known:1;
+} osi_linux = { OSI_LINUX_ENABLE, 0, 0, 0};
static void __init acpi_request_region (struct acpi_generic_address *addr,
unsigned int length, char *desc)
@@ -133,7 +177,6 @@ device_initcall(acpi_reserve_resources);
acpi_status __init acpi_os_initialize(void)
{
- dmi_check_system(acpi_osl_dmi_table);
return AE_OK;
}
@@ -207,8 +250,12 @@ acpi_physical_address __init acpi_os_get_root_pointer(void)
"System description tables not found\n");
return 0;
}
- } else
- return acpi_find_rsdp();
+ } else {
+ acpi_physical_address pa = 0;
+
+ acpi_find_root_pointer(&pa);
+ return pa;
+ }
}
void __iomem *acpi_os_map_memory(acpi_physical_address phys, acpi_size size)
@@ -964,13 +1011,37 @@ static int __init acpi_os_name_setup(char *str)
__setup("acpi_os_name=", acpi_os_name_setup);
-static void enable_osi_linux(int enable) {
+static void __init set_osi_linux(unsigned int enable)
+{
+ if (osi_linux.enable != enable) {
+ osi_linux.enable = enable;
+ printk(KERN_NOTICE PREFIX "%sed _OSI(Linux)\n",
+ enable ? "Add": "Delet");
+ }
+ return;
+}
+
+static void __init acpi_cmdline_osi_linux(unsigned int enable)
+{
+ osi_linux.cmdline = 1; /* cmdline set the default */
+ set_osi_linux(enable);
+
+ return;
+}
+
+void __init acpi_dmi_osi_linux(int enable, const struct dmi_system_id *d)
+{
+ osi_linux.dmi = 1; /* DMI knows that this box asks OSI(Linux) */
+
+ printk(KERN_NOTICE PREFIX "DMI detected: %s\n", d->ident);
+
+ if (enable == -1)
+ return;
+
+ osi_linux.known = 1; /* DMI knows which OSI(Linux) default needed */
- if (osi_linux != enable)
- printk(KERN_INFO PREFIX "%sabled _OSI(Linux)\n",
- enable ? "En": "Dis");
+ set_osi_linux(enable);
- osi_linux = enable;
return;
}
@@ -987,12 +1058,12 @@ static int __init acpi_osi_setup(char *str)
printk(KERN_INFO PREFIX "_OSI method disabled\n");
acpi_gbl_create_osi_method = FALSE;
} else if (!strcmp("!Linux", str)) {
- enable_osi_linux(0);
+ acpi_cmdline_osi_linux(0); /* !enable */
} else if (*str == '!') {
if (acpi_osi_invalidate(++str) == AE_OK)
printk(KERN_INFO PREFIX "Deleted _OSI(%s)\n", str);
} else if (!strcmp("Linux", str)) {
- enable_osi_linux(1);
+ acpi_cmdline_osi_linux(1); /* enable */
} else if (*osi_additional_string == '\0') {
strncpy(osi_additional_string, str, OSI_STRING_LENGTH_MAX);
printk(KERN_INFO PREFIX "Added _OSI(%s)\n", str);
@@ -1141,6 +1212,34 @@ acpi_status acpi_os_release_object(acpi_cache_t * cache, void *object)
return (AE_OK);
}
+/**
+ * acpi_dmi_dump - dump DMI slots needed for blacklist entry
+ *
+ * Returns 0 on success
+ */
+int acpi_dmi_dump(void)
+{
+
+ if (!dmi_available)
+ return -1;
+
+ printk(KERN_NOTICE PREFIX "DMI System Vendor: %s\n",
+ dmi_get_slot(DMI_SYS_VENDOR));
+ printk(KERN_NOTICE PREFIX "DMI Product Name: %s\n",
+ dmi_get_slot(DMI_PRODUCT_NAME));
+ printk(KERN_NOTICE PREFIX "DMI Product Version: %s\n",
+ dmi_get_slot(DMI_PRODUCT_VERSION));
+ printk(KERN_NOTICE PREFIX "DMI Board Name: %s\n",
+ dmi_get_slot(DMI_BOARD_NAME));
+ printk(KERN_NOTICE PREFIX "DMI BIOS Vendor: %s\n",
+ dmi_get_slot(DMI_BIOS_VENDOR));
+ printk(KERN_NOTICE PREFIX "DMI BIOS Date: %s\n",
+ dmi_get_slot(DMI_BIOS_DATE));
+
+ return 0;
+}
+
+
/******************************************************************************
*
* FUNCTION: acpi_os_validate_interface
@@ -1160,13 +1259,29 @@ acpi_os_validate_interface (char *interface)
if (!strncmp(osi_additional_string, interface, OSI_STRING_LENGTH_MAX))
return AE_OK;
if (!strcmp("Linux", interface)) {
- printk(KERN_WARNING PREFIX
- "System BIOS is requesting _OSI(Linux)\n");
- printk(KERN_WARNING PREFIX
- "If \"acpi_osi=Linux\" works better,\n"
- "Please send dmidecode "
- "to linux-acpi@vger.kernel.org\n");
- if(osi_linux)
+
+ printk(KERN_NOTICE PREFIX
+ "BIOS _OSI(Linux) query %s%s\n",
+ osi_linux.enable ? "honored" : "ignored",
+ osi_linux.cmdline ? " via cmdline" :
+ osi_linux.dmi ? " via DMI" : "");
+
+ if (!osi_linux.dmi) {
+ if (acpi_dmi_dump())
+ printk(KERN_NOTICE PREFIX
+ "[please extract dmidecode output]\n");
+ printk(KERN_NOTICE PREFIX
+ "Please send DMI info above to "
+ "linux-acpi@vger.kernel.org\n");
+ }
+ if (!osi_linux.known && !osi_linux.cmdline) {
+ printk(KERN_NOTICE PREFIX
+ "If \"acpi_osi=%sLinux\" works better, "
+ "please notify linux-acpi@vger.kernel.org\n",
+ osi_linux.enable ? "!" : "");
+ }
+
+ if (osi_linux.enable)
return AE_OK;
}
return AE_SUPPORT;
@@ -1198,28 +1313,4 @@ acpi_os_validate_address (
return AE_OK;
}
-#ifdef CONFIG_DMI
-static int dmi_osi_linux(const struct dmi_system_id *d)
-{
- printk(KERN_NOTICE "%s detected: enabling _OSI(Linux)\n", d->ident);
- enable_osi_linux(1);
- return 0;
-}
-
-static struct dmi_system_id acpi_osl_dmi_table[] __initdata = {
- /*
- * Boxes that need _OSI(Linux)
- */
- {
- .callback = dmi_osi_linux,
- .ident = "Intel Napa CRB",
- .matches = {
- DMI_MATCH(DMI_BOARD_VENDOR, "Intel Corporation"),
- DMI_MATCH(DMI_BOARD_NAME, "MPAD-MSAE Customer Reference Boards"),
- },
- },
- {}
-};
-#endif /* CONFIG_DMI */
-
#endif
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-27 17:47:28 +0000