From: Al Stone al.stone@linaro.org
In order to deprecate the use of _OSI for arm64 or other new architectures, we need to make the default handler something we can change for various platforms. This patch moves the definition of acpi_osi_handler() -- the function used by ACPICA as a callback for evaluating _OSI -- into a separate file. Subsequent patches will change which files get built so that we can then build the version of _OSI we need for a particular architecture.
There is no functional change.
Signed-off-by: Al Stone al.stone@linaro.org --- drivers/acpi/Makefile | 2 +- drivers/acpi/osi.c | 95 +++++++++++++++++++++++++++++++++++++++++++++++++++ drivers/acpi/osl.c | 24 ------------- include/linux/acpi.h | 1 + 4 files changed, 97 insertions(+), 25 deletions(-) create mode 100644 drivers/acpi/osi.c
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 13536d8..97191eb 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -18,7 +18,7 @@ obj-y += acpi.o \ acpica/
# All the builtin files are in the "acpi." module_param namespace. -acpi-y += osl.o utils.o reboot.o +acpi-y += osl.o utils.o reboot.o osi.o acpi-y += nvs.o
# Power management related files diff --git a/drivers/acpi/osi.c b/drivers/acpi/osi.c new file mode 100644 index 0000000..f23aa70 --- /dev/null +++ b/drivers/acpi/osi.c @@ -0,0 +1,95 @@ +/* + * osi.c - _OSI implementation (moved from drivers/acpi/osl.c) + * + * Copyright (C) 2000 Andrew Henroid + * Copyright (C) 2001, 2002 Andy Grover andrew.grover@intel.com + * Copyright (C) 2001, 2002 Paul Diefenbaugh paul.s.diefenbaugh@intel.com + * Copyright (c) 2008 Intel Corporation + * Author: Matthew Wilcox willy@linux.intel.com + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + */ + +#include <linux/acpi.h> + +#define _COMPONENT ACPI_OS_SERVICES +ACPI_MODULE_NAME("osi"); + +#define PREFIX "ACPI: " + +/* + * The story of _OSI(Linux) + * + * From pre-history through Linux-2.6.22, + * Linux responded TRUE upon a BIOS OSI(Linux) query. + * + * Unfortunately, reference BIOS writers got wind of this + * and put OSI(Linux) in their example code, quickly exposing + * this string as ill-conceived and opening the door to + * an un-bounded number of BIOS incompatibilities. + * + * For example, OSI(Linux) was used on resume to re-POST a + * video card on one system, because Linux at that time + * could not do a speedy restore in its native driver. + * But then upon gaining quick native restore capability, + * Linux has no way to tell the BIOS to skip the time-consuming + * POST -- putting Linux at a permanent performance disadvantage. + * On another system, the BIOS writer used OSI(Linux) + * to infer native OS support for IPMI! On other systems, + * OSI(Linux) simply got in the way of Linux claiming to + * be compatible with other operating systems, exposing + * BIOS issues such as skipped device initialization. + * + * So "Linux" turned out to be a really poor chose of + * OSI string, and from Linux-2.6.23 onward we respond FALSE. + * + * BIOS writers should NOT query _OSI(Linux) on future systems. + * Linux will complain on the console when it sees it, and return FALSE. + * To get Linux to return TRUE for your system will require + * a kernel source update to add a DMI entry, + * or boot with "acpi_osi=Linux" + */ + +static struct osi_linux { + unsigned int enable:1; + unsigned int dmi:1; + unsigned int cmdline:1; + unsigned int default_disabling:1; +} osi_linux = {0, 0, 0, 0}; + +u32 acpi_osi_handler(acpi_string interface, u32 supported) +{ + if (!strcmp("Linux", interface)) { + + pr_notice_once(FW_BUG PREFIX + "BIOS _OSI(Linux) query %s%s\n", + osi_linux.enable ? "honored" : "ignored", + osi_linux.cmdline ? " via cmdline" : + osi_linux.dmi ? " via DMI" : ""); + } + + if (!strcmp("Darwin", interface)) { + /* + * Apple firmware will behave poorly if it receives positive + * answers to "Darwin" and any other OS. Respond positively + * to Darwin and then disable all other vendor strings. + */ + acpi_update_interfaces(ACPI_DISABLE_ALL_VENDOR_STRINGS); + supported = ACPI_UINT32_MAX; + } + + return supported; +} diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index af6dda7..823a08f 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -136,30 +136,6 @@ static struct osi_linux { unsigned int default_disabling:1; } osi_linux = {0, 0, 0, 0};
-static u32 acpi_osi_handler(acpi_string interface, u32 supported) -{ - if (!strcmp("Linux", interface)) { - - pr_notice_once(FW_BUG PREFIX - "BIOS _OSI(Linux) query %s%s\n", - osi_linux.enable ? "honored" : "ignored", - osi_linux.cmdline ? " via cmdline" : - osi_linux.dmi ? " via DMI" : ""); - } - - if (!strcmp("Darwin", interface)) { - /* - * Apple firmware will behave poorly if it receives positive - * answers to "Darwin" and any other OS. Respond positively - * to Darwin and then disable all other vendor strings. - */ - acpi_update_interfaces(ACPI_DISABLE_ALL_VENDOR_STRINGS); - supported = ACPI_UINT32_MAX; - } - - return supported; -} - static void __init acpi_request_region(struct acpi_generic_address *gas, unsigned int length, char *desc) { diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 9a01d5d..a7c402a 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -281,6 +281,7 @@ static inline int acpi_video_display_switch_support(void) extern int acpi_blacklisted(void); extern void acpi_dmi_osi_linux(int enable, const struct dmi_system_id *d); extern void acpi_osi_setup(char *str); +extern u32 acpi_osi_handler(acpi_string interface, u32 supported);
#ifdef CONFIG_ACPI_NUMA int acpi_get_node(acpi_handle handle);