Fixed MTP to work with TWRP

Documentation/acpi/apei/einj.txt

@@ -0,0 +1,129 @@
+			APEI Error INJection
+			~~~~~~~~~~~~~~~~~~~~
+
+EINJ provides a hardware error injection mechanism
+It is very useful for debugging and testing of other APEI and RAS features.
+
+To use EINJ, make sure the following are enabled in your kernel
+configuration:
+
+CONFIG_DEBUG_FS
+CONFIG_ACPI_APEI
+CONFIG_ACPI_APEI_EINJ
+
+The user interface of EINJ is debug file system, under the
+directory apei/einj. The following files are provided.
+
+- available_error_type
+  Reading this file returns the error injection capability of the
+  platform, that is, which error types are supported. The error type
+  definition is as follow, the left field is the error type value, the
+  right field is error description.
+
+    0x00000001	Processor Correctable
+    0x00000002	Processor Uncorrectable non-fatal
+    0x00000004	Processor Uncorrectable fatal
+    0x00000008  Memory Correctable
+    0x00000010  Memory Uncorrectable non-fatal
+    0x00000020  Memory Uncorrectable fatal
+    0x00000040	PCI Express Correctable
+    0x00000080	PCI Express Uncorrectable fatal
+    0x00000100	PCI Express Uncorrectable non-fatal
+    0x00000200	Platform Correctable
+    0x00000400	Platform Uncorrectable non-fatal
+    0x00000800	Platform Uncorrectable fatal
+
+  The format of file contents are as above, except there are only the
+  available error type lines.
+
+- error_type
+  This file is used to set the error type value. The error type value
+  is defined in "available_error_type" description.
+
+- error_inject
+  Write any integer to this file to trigger the error
+  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. [Unless "flag" is set - see above]
+
+- param2
+  This file is used to set the second error parameter value. Effect of
+  parameter depends on error_type specified. For example, if error
+  type is memory related type, the param2 should be a physical memory
+  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
+  trigger phase, which *may* allow the user to cause the error in some other
+  context by a simple access to the cpu, memory location, or device that is
+  the target of the error injection. Whether this actually works depends
+  on what operations the BIOS actually includes in the trigger phase.
+
+BIOS versions based in the ACPI 4.0 specification have limited options
+to control where the errors are injected.  Your BIOS may support an
+extension (enabled with the param_extension=1 module parameter, or
+boot command line einj.param_extension=1). This allows the address
+and mask for memory injections to be specified by the param1 and
+param2 files in apei/einj.
+
+BIOS versions using the ACPI 5.0 specification have more control over
+the target of the injection. For processor related errors (type 0x1,
+0x2 and 0x4) the APICID of the target should be provided using the
+param1 file in apei/einj. For memory errors (type 0x8, 0x10 and 0x20)
+the address is set using param1 with a mask in param2 (0x0 is equivalent
+to all ones). For PCI express errors (type 0x40, 0x80 and 0x100) the
+segment, bus, device and function are specified using param1:
+
+         31     24 23    16 15    11 10      8  7        0
+	+-------------------------------------------------+
+	| segment |   bus  | device | function | reserved |
+	+-------------------------------------------------+
+
+An ACPI 5.0 BIOS may also allow vendor specific errors to be injected.
+In this case a file named vendor will contain identifying information
+from the BIOS that hopefully will allow an application wishing to use
+the vendor specific extension to tell that they are running on a BIOS
+that supports it. All vendor extensions have the 0x80000000 bit set in
+error_type. A file vendor_flags controls the interpretation of param1
+and param2 (1 = PROCESSOR, 2 = MEMORY, 4 = PCI). See your BIOS vendor
+documentation for details (and expect changes to this API if vendors
+creativity in using this feature expands beyond our expectations).
+
+Example:
+# cd /sys/kernel/debug/apei/einj
+# cat available_error_type		# See which errors can be injected
+0x00000002	Processor Uncorrectable non-fatal
+0x00000008	Memory Correctable
+0x00000010	Memory Uncorrectable non-fatal
+# echo 0x12345000 > param1		# Set memory address for injection
+# echo 0xfffffffffffff000 > param2	# Mask - anywhere in this page
+# echo 0x8 > error_type			# Choose correctable memory error
+# echo 1 > error_inject			# Inject now
+
+
+For more information about EINJ, please refer to ACPI specification
+version 4.0, section 17.5 and ACPI 5.0, section 18.6.