From d4b7dc499daae909e62dc260b95cd618f2970ded Mon Sep 17 00:00:00 2001 From: Len Brown Date: Wed, 23 Jan 2008 20:50:56 -0500 Subject: [PATCH] ACPI: make _OSI(Linux) console messages smarter If BIOS invokes _OSI(Linux), the kernel response depends on what the ACPI DMI list knows about the system, and that is reflectd in dmesg: 1) System unknown to DMI: ACPI: BIOS _OSI(Linux) query ignored ACPI: DMI System Vendor: LENOVO ACPI: DMI Product Name: 7661W1P ACPI: DMI Product Version: ThinkPad T61 ACPI: DMI Board Name: 7661W1P ACPI: DMI BIOS Vendor: LENOVO ACPI: DMI BIOS Date: 10/18/2007 ACPI: Please send DMI info above to linux-acpi@vger.kernel.org ACPI: If "acpi_osi=Linux" works better, please notify linux-acpi@vger.kernel.org 2) System known to DMI, but effect of OSI(Linux) unknown: ACPI: DMI detected: Lenovo ThinkPad T61 ... ACPI: BIOS _OSI(Linux) query ignored via DMI ACPI: If "acpi_osi=Linux" works better, please notify linux-acpi@vger.kernel.org 3) System known to DMI, which disables _OSI(Linux): ACPI: DMI detected: Lenovo ThinkPad T61 ... ACPI: BIOS _OSI(Linux) query ignored via DMI 4) System known to DMI, which enable _OSI(Linux): ACPI: DMI detected: Lenovo ThinkPad T61 ACPI: Added _OSI(Linux) ... ACPI: BIOS _OSI(Linux) query honored via DMI cmdline overrides take precidence over the built-in default and the DMI prescribed default. cmdline "acpi_osi=Linux" results in: ACPI: BIOS _OSI(Linux) query honored via cmdline Signed-off-by: Len Brown --- drivers/acpi/blacklist.c | 11 ++++ drivers/acpi/osl.c | 122 ++++++++++++++++++++++++++++++++------- include/linux/acpi.h | 7 ++- 3 files changed, 118 insertions(+), 22 deletions(-) diff --git a/drivers/acpi/blacklist.c b/drivers/acpi/blacklist.c index 3ec110ce00..018fc16c44 100644 --- a/drivers/acpi/blacklist.c +++ b/drivers/acpi/blacklist.c @@ -3,6 +3,7 @@ * * Check to see if the given machine has a known bad ACPI BIOS * or if the BIOS is too old. + * Check given machine against acpi_osi_dmi_table[]. * * Copyright (C) 2004 Len Brown * Copyright (C) 2002 Andy Grover @@ -50,6 +51,8 @@ struct acpi_blacklist_item { u32 is_critical_error; }; +static struct dmi_system_id acpi_osi_dmi_table[] __initdata; + /* * POLICY: If *anything* doesn't work, put it on the blacklist. * If they are critical errors, mark it critical, and abort driver load. @@ -165,5 +168,13 @@ int __init acpi_blacklisted(void) blacklisted += blacklist_by_year(); + dmi_check_system(acpi_osi_dmi_table); + return blacklisted; } +#ifdef CONFIG_DMI +static struct dmi_system_id acpi_osi_dmi_table[] __initdata = { + {} +}; + +#endif /* CONFIG_DMI */ diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index 15f095ea79..e53fb516f9 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -77,7 +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 + +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) @@ -959,13 +1007,37 @@ 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; } @@ -982,12 +1054,12 @@ 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); @@ -1183,19 +1255,29 @@ 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"); - 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"); + printk(KERN_NOTICE PREFIX - "If \"acpi_osi=%sLinux\" works better, " - "please notify linux-acpi@vger.kernel.org\n", - osi_linux ? "!" : ""); - if(osi_linux) + "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; diff --git a/include/linux/acpi.h b/include/linux/acpi.h index e3c16c981e..63f2e6ed69 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -40,6 +40,7 @@ #include #include #include +#include #ifdef CONFIG_ACPI @@ -192,7 +193,9 @@ extern int ec_transaction(u8 command, #endif /*CONFIG_ACPI_EC*/ extern int acpi_blacklisted(void); -extern void acpi_bios_year(char *s); +#ifdef CONFIG_DMI +extern void acpi_dmi_osi_linux(int enable, const struct dmi_system_id *d); +#endif #ifdef CONFIG_ACPI_NUMA int acpi_get_pxm(acpi_handle handle); @@ -226,5 +229,5 @@ static inline int acpi_boot_table_init(void) return 0; } -#endif /* CONFIG_ACPI */ +#endif /* !CONFIG_ACPI */ #endif /*_LINUX_ACPI_H*/ -- 2.39.5