diff options
Diffstat (limited to 'Documentation/acpi')
-rw-r--r-- | Documentation/acpi/apei/einj.txt | 19 | ||||
-rw-r--r-- | Documentation/acpi/enumeration.txt | 36 |
2 files changed, 25 insertions, 30 deletions
diff --git a/Documentation/acpi/apei/einj.txt b/Documentation/acpi/apei/einj.txt index a58b63da1a36..f51861bcb07b 100644 --- a/Documentation/acpi/apei/einj.txt +++ b/Documentation/acpi/apei/einj.txt @@ -45,11 +45,22 @@ directory apei/einj. The following files are provided. injection. Before this, please specify all necessary error parameters. +- flags + Present for kernel version 3.13 and above. Used to specify which + of param{1..4} are valid and should be used by BIOS during injection. + Value is a bitmask as specified in ACPI5.0 spec for the + SET_ERROR_TYPE_WITH_ADDRESS data structure: + Bit 0 - Processor APIC field valid (see param3 below) + Bit 1 - Memory address and mask valid (param1 and param2) + Bit 2 - PCIe (seg,bus,dev,fn) valid (param4 below) + If set to zero, legacy behaviour is used where the type of injection + specifies just one bit set, and param1 is multiplexed. + - param1 This file is used to set the first error parameter value. Effect of parameter depends on error_type specified. For example, if error type is memory related type, the param1 should be a valid physical - memory address. + memory address. [Unless "flag" is set - see above] - param2 This file is used to set the second error parameter value. Effect of @@ -58,6 +69,12 @@ directory apei/einj. The following files are provided. address mask. Linux requires page or narrower granularity, say, 0xfffffffffffff000. +- param3 + Used when the 0x1 bit is set in "flag" to specify the APIC id + +- param4 + Used when the 0x4 bit is set in "flag" to specify target PCIe device + - notrigger The EINJ mechanism is a two step process. First inject the error, then perform some actions to trigger it. Setting "notrigger" to 1 skips the diff --git a/Documentation/acpi/enumeration.txt b/Documentation/acpi/enumeration.txt index b994bcb32b92..2a1519b87177 100644 --- a/Documentation/acpi/enumeration.txt +++ b/Documentation/acpi/enumeration.txt @@ -293,36 +293,13 @@ the device to the driver. For example: These GPIO numbers are controller relative and path "\\_SB.PCI0.GPI0" specifies the path to the controller. In order to use these GPIOs in Linux -we need to translate them to the Linux GPIO numbers. +we need to translate them to the corresponding Linux GPIO descriptors. -In a simple case of just getting the Linux GPIO number from device -resources one can use acpi_get_gpio_by_index() helper function. It takes -pointer to the device and index of the GpioIo/GpioInt descriptor in the -device resources list. For example: +There is a standard GPIO API for that and is documented in +Documentation/gpio.txt. - int gpio_irq, gpio_power; - int ret; - - gpio_irq = acpi_get_gpio_by_index(dev, 1, NULL); - if (gpio_irq < 0) - /* handle error */ - - gpio_power = acpi_get_gpio_by_index(dev, 0, NULL); - if (gpio_power < 0) - /* handle error */ - - /* Now we can use the GPIO numbers */ - -Other GpioIo parameters must be converted first by the driver to be -suitable to the gpiolib before passing them. - -In case of GpioInt resource an additional call to gpio_to_irq() must be -done before calling request_irq(). - -Note that the above API is ACPI specific and not recommended for drivers -that need to support non-ACPI systems. The recommended way is to use -the descriptor based GPIO interfaces. The above example looks like this -when converted to the GPIO desc: +In the above example we can get the corresponding two GPIO descriptors with +a code like this: #include <linux/gpio/consumer.h> ... @@ -339,4 +316,5 @@ when converted to the GPIO desc: /* Now we can use the GPIO descriptors */ -See also Documentation/gpio.txt. +There are also devm_* versions of these functions which release the +descriptors once the device is released. |