Em Wed, 24 Apr 2019 00:28:31 +0800 Changbin Du <changbin.du@xxxxxxxxx> escreveu: > This converts the plain text documentation to reStructuredText format and > add it to Sphinx TOC tree. No essential content change. > > Signed-off-by: Changbin Du <changbin.du@xxxxxxxxx> > --- > Documentation/firmware-guide/acpi/index.rst | 1 + > .../acpi/namespace.rst} | 310 +++++++++--------- > 2 files changed, 161 insertions(+), 150 deletions(-) > rename Documentation/{acpi/namespace.txt => firmware-guide/acpi/namespace.rst} (54%) > > diff --git a/Documentation/firmware-guide/acpi/index.rst b/Documentation/firmware-guide/acpi/index.rst > index 0ec7d072ba22..210ad8acd6df 100644 > --- a/Documentation/firmware-guide/acpi/index.rst > +++ b/Documentation/firmware-guide/acpi/index.rst > @@ -7,3 +7,4 @@ ACPI Support > .. toctree:: > :maxdepth: 1 > > + namespace > diff --git a/Documentation/acpi/namespace.txt b/Documentation/firmware-guide/acpi/namespace.rst > similarity index 54% > rename from Documentation/acpi/namespace.txt > rename to Documentation/firmware-guide/acpi/namespace.rst > index 1860cb3865c6..443f0e5d0617 100644 > --- a/Documentation/acpi/namespace.txt > +++ b/Documentation/firmware-guide/acpi/namespace.rst > @@ -1,85 +1,88 @@ > +.. SPDX-License-Identifier: GPL-2.0 > +.. include:: <isonum.txt> > + > +=================================================== > ACPI Device Tree - Representation of ACPI Namespace > +=================================================== > + > +:Copyright: |copy| 2013, Intel Corporation > + > +:Author: Lv Zheng <lv.zheng@xxxxxxxxx> > + > +:Abstract: The Linux ACPI subsystem converts ACPI namespace objects into a Linux > + device tree under the /sys/devices/LNXSYSTEM:00 and updates it upon > + receiving ACPI hotplug notification events. For each device object > + in this hierarchy there is a corresponding symbolic link in the > + /sys/bus/acpi/devices. > + This document illustrates the structure of the ACPI device tree. Well, this is a matter of preference. I would add Abstract as a chapter, as this would make it part of the top index, with can be useful. In any case: Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx> > + > +:Credit: Thanks for the help from Zhang Rui <rui.zhang@xxxxxxxxx> and > + Rafael J.Wysocki <rafael.j.wysocki@xxxxxxxxx>. > + > + > +ACPI Definition Blocks > +====================== > + > +The ACPI firmware sets up RSDP (Root System Description Pointer) in the > +system memory address space pointing to the XSDT (Extended System > +Description Table). The XSDT always points to the FADT (Fixed ACPI > +Description Table) using its first entry, the data within the FADT > +includes various fixed-length entries that describe fixed ACPI features > +of the hardware. The FADT contains a pointer to the DSDT > +(Differentiated System Descripition Table). The XSDT also contains > +entries pointing to possibly multiple SSDTs (Secondary System > +Description Table). > + > +The DSDT and SSDT data is organized in data structures called definition > +blocks that contain definitions of various objects, including ACPI > +control methods, encoded in AML (ACPI Machine Language). The data block > +of the DSDT along with the contents of SSDTs represents a hierarchical > +data structure called the ACPI namespace whose topology reflects the > +structure of the underlying hardware platform. > + > +The relationships between ACPI System Definition Tables described above > +are illustrated in the following diagram:: > + > + +---------+ +-------+ +--------+ +------------------------+ > + | RSDP | +->| XSDT | +->| FADT | | +-------------------+ | > + +---------+ | +-------+ | +--------+ +-|->| DSDT | | > + | Pointer | | | Entry |-+ | ...... | | | +-------------------+ | > + +---------+ | +-------+ | X_DSDT |--+ | | Definition Blocks | | > + | Pointer |-+ | ..... | | ...... | | +-------------------+ | > + +---------+ +-------+ +--------+ | +-------------------+ | > + | Entry |------------------|->| SSDT | | > + +- - - -+ | +-------------------| | > + | Entry | - - - - - - - -+ | | Definition Blocks | | > + +- - - -+ | | +-------------------+ | > + | | +- - - - - - - - - -+ | > + +-|->| SSDT | | > + | +-------------------+ | > + | | Definition Blocks | | > + | +- - - - - - - - - -+ | > + +------------------------+ > + | > + OSPM Loading | > + \|/ > + +----------------+ > + | ACPI Namespace | > + +----------------+ > + > + Figure 1. ACPI Definition Blocks > + > +.. note:: RSDP can also contain a pointer to the RSDT (Root System > + Description Table). Platforms provide RSDT to enable > + compatibility with ACPI 1.0 operating systems. The OS is expected > + to use XSDT, if present. > + > + > +Example ACPI Namespace > +====================== > + > +All definition blocks are loaded into a single namespace. The namespace > +is a hierarchy of objects identified by names and paths. > +The following naming conventions apply to object names in the ACPI > +namespace: > > -Copyright (C) 2013, Intel Corporation > -Author: Lv Zheng <lv.zheng@xxxxxxxxx> > - > - > -Abstract: > - > -The Linux ACPI subsystem converts ACPI namespace objects into a Linux > -device tree under the /sys/devices/LNXSYSTEM:00 and updates it upon > -receiving ACPI hotplug notification events. For each device object in this > -hierarchy there is a corresponding symbolic link in the > -/sys/bus/acpi/devices. > -This document illustrates the structure of the ACPI device tree. > - > - > -Credit: > - > -Thanks for the help from Zhang Rui <rui.zhang@xxxxxxxxx> and Rafael J. > -Wysocki <rafael.j.wysocki@xxxxxxxxx>. > - > - > -1. ACPI Definition Blocks > - > - The ACPI firmware sets up RSDP (Root System Description Pointer) in the > - system memory address space pointing to the XSDT (Extended System > - Description Table). The XSDT always points to the FADT (Fixed ACPI > - Description Table) using its first entry, the data within the FADT > - includes various fixed-length entries that describe fixed ACPI features > - of the hardware. The FADT contains a pointer to the DSDT > - (Differentiated System Descripition Table). The XSDT also contains > - entries pointing to possibly multiple SSDTs (Secondary System > - Description Table). > - > - The DSDT and SSDT data is organized in data structures called definition > - blocks that contain definitions of various objects, including ACPI > - control methods, encoded in AML (ACPI Machine Language). The data block > - of the DSDT along with the contents of SSDTs represents a hierarchical > - data structure called the ACPI namespace whose topology reflects the > - structure of the underlying hardware platform. > - > - The relationships between ACPI System Definition Tables described above > - are illustrated in the following diagram. > - > - +---------+ +-------+ +--------+ +------------------------+ > - | RSDP | +->| XSDT | +->| FADT | | +-------------------+ | > - +---------+ | +-------+ | +--------+ +-|->| DSDT | | > - | Pointer | | | Entry |-+ | ...... | | | +-------------------+ | > - +---------+ | +-------+ | X_DSDT |--+ | | Definition Blocks | | > - | Pointer |-+ | ..... | | ...... | | +-------------------+ | > - +---------+ +-------+ +--------+ | +-------------------+ | > - | Entry |------------------|->| SSDT | | > - +- - - -+ | +-------------------| | > - | Entry | - - - - - - - -+ | | Definition Blocks | | > - +- - - -+ | | +-------------------+ | > - | | +- - - - - - - - - -+ | > - +-|->| SSDT | | > - | +-------------------+ | > - | | Definition Blocks | | > - | +- - - - - - - - - -+ | > - +------------------------+ > - | > - OSPM Loading | > - \|/ > - +----------------+ > - | ACPI Namespace | > - +----------------+ > - > - Figure 1. ACPI Definition Blocks > - > - NOTE: RSDP can also contain a pointer to the RSDT (Root System > - Description Table). Platforms provide RSDT to enable > - compatibility with ACPI 1.0 operating systems. The OS is expected > - to use XSDT, if present. > - > - > -2. Example ACPI Namespace > - > - All definition blocks are loaded into a single namespace. The namespace > - is a hierarchy of objects identified by names and paths. > - The following naming conventions apply to object names in the ACPI > - namespace: > 1. All names are 32 bits long. > 2. The first byte of a name must be one of 'A' - 'Z', '_'. > 3. Each of the remaining bytes of a name must be one of 'A' - 'Z', '0' > @@ -91,7 +94,7 @@ Wysocki <rafael.j.wysocki@xxxxxxxxx>. > (i.e. names prepended with '^' are relative to the parent of the > current namespace node). > > - The figure below shows an example ACPI namespace. > +The figure below shows an example ACPI namespace:: > > +------+ > | \ | Root > @@ -184,19 +187,20 @@ Wysocki <rafael.j.wysocki@xxxxxxxxx>. > Figure 2. Example ACPI Namespace > > > -3. Linux ACPI Device Objects > +Linux ACPI Device Objects > +========================= > > - The Linux kernel's core ACPI subsystem creates struct acpi_device > - objects for ACPI namespace objects representing devices, power resources > - processors, thermal zones. Those objects are exported to user space via > - sysfs as directories in the subtree under /sys/devices/LNXSYSTM:00. The > - format of their names is <bus_id:instance>, where 'bus_id' refers to the > - ACPI namespace representation of the given object and 'instance' is used > - for distinguishing different object of the same 'bus_id' (it is > - two-digit decimal representation of an unsigned integer). > +The Linux kernel's core ACPI subsystem creates struct acpi_device > +objects for ACPI namespace objects representing devices, power resources > +processors, thermal zones. Those objects are exported to user space via > +sysfs as directories in the subtree under /sys/devices/LNXSYSTM:00. The > +format of their names is <bus_id:instance>, where 'bus_id' refers to the > +ACPI namespace representation of the given object and 'instance' is used > +for distinguishing different object of the same 'bus_id' (it is > +two-digit decimal representation of an unsigned integer). > > - The value of 'bus_id' depends on the type of the object whose name it is > - part of as listed in the table below. > +The value of 'bus_id' depends on the type of the object whose name it is > +part of as listed in the table below:: > > +---+-----------------+-------+----------+ > | | Object/Feature | Table | bus_id | > @@ -226,10 +230,11 @@ Wysocki <rafael.j.wysocki@xxxxxxxxx>. > > Table 1. ACPI Namespace Objects Mapping > > - The following rules apply when creating struct acpi_device objects on > - the basis of the contents of ACPI System Description Tables (as > - indicated by the letter in the first column and the notation in the > - second column of the table above): > +The following rules apply when creating struct acpi_device objects on > +the basis of the contents of ACPI System Description Tables (as > +indicated by the letter in the first column and the notation in the > +second column of the table above): > + > N: > The object's source is an ACPI namespace node (as indicated by the > named object's type in the second column). In that case the object's > @@ -249,13 +254,14 @@ Wysocki <rafael.j.wysocki@xxxxxxxxx>. > struct acpi_device object with LNXVIDEO 'bus_id' will be created for > it. > > - The third column of the above table indicates which ACPI System > - Description Tables contain information used for the creation of the > - struct acpi_device objects represented by the given row (xSDT means DSDT > - or SSDT). > +The third column of the above table indicates which ACPI System > +Description Tables contain information used for the creation of the > +struct acpi_device objects represented by the given row (xSDT means DSDT > +or SSDT). > + > +The forth column of the above table indicates the 'bus_id' generation > +rule of the struct acpi_device object: > > - The forth column of the above table indicates the 'bus_id' generation > - rule of the struct acpi_device object: > _HID: > _HID in the last column of the table means that the object's bus_id > is derived from the _HID/_CID identification objects present under > @@ -275,45 +281,47 @@ Wysocki <rafael.j.wysocki@xxxxxxxxx>. > object's bus_id. > > > -4. Linux ACPI Physical Device Glue > - > - ACPI device (i.e. struct acpi_device) objects may be linked to other > - objects in the Linux' device hierarchy that represent "physical" devices > - (for example, devices on the PCI bus). If that happens, it means that > - the ACPI device object is a "companion" of a device otherwise > - represented in a different way and is used (1) to provide configuration > - information on that device which cannot be obtained by other means and > - (2) to do specific things to the device with the help of its ACPI > - control methods. One ACPI device object may be linked this way to > - multiple "physical" devices. > - > - If an ACPI device object is linked to a "physical" device, its sysfs > - directory contains the "physical_node" symbolic link to the sysfs > - directory of the target device object. In turn, the target device's > - sysfs directory will then contain the "firmware_node" symbolic link to > - the sysfs directory of the companion ACPI device object. > - The linking mechanism relies on device identification provided by the > - ACPI namespace. For example, if there's an ACPI namespace object > - representing a PCI device (i.e. a device object under an ACPI namespace > - object representing a PCI bridge) whose _ADR returns 0x00020000 and the > - bus number of the parent PCI bridge is 0, the sysfs directory > - representing the struct acpi_device object created for that ACPI > - namespace object will contain the 'physical_node' symbolic link to the > - /sys/devices/pci0000:00/0000:00:02:0/ sysfs directory of the > - corresponding PCI device. > - > - The linking mechanism is generally bus-specific. The core of its > - implementation is located in the drivers/acpi/glue.c file, but there are > - complementary parts depending on the bus types in question located > - elsewhere. For example, the PCI-specific part of it is located in > - drivers/pci/pci-acpi.c. > - > - > -5. Example Linux ACPI Device Tree > - > - The sysfs hierarchy of struct acpi_device objects corresponding to the > - example ACPI namespace illustrated in Figure 2 with the addition of > - fixed PWR_BUTTON/SLP_BUTTON devices is shown below. > +Linux ACPI Physical Device Glue > +=============================== > + > +ACPI device (i.e. struct acpi_device) objects may be linked to other > +objects in the Linux' device hierarchy that represent "physical" devices > +(for example, devices on the PCI bus). If that happens, it means that > +the ACPI device object is a "companion" of a device otherwise > +represented in a different way and is used (1) to provide configuration > +information on that device which cannot be obtained by other means and > +(2) to do specific things to the device with the help of its ACPI > +control methods. One ACPI device object may be linked this way to > +multiple "physical" devices. > + > +If an ACPI device object is linked to a "physical" device, its sysfs > +directory contains the "physical_node" symbolic link to the sysfs > +directory of the target device object. In turn, the target device's > +sysfs directory will then contain the "firmware_node" symbolic link to > +the sysfs directory of the companion ACPI device object. > +The linking mechanism relies on device identification provided by the > +ACPI namespace. For example, if there's an ACPI namespace object > +representing a PCI device (i.e. a device object under an ACPI namespace > +object representing a PCI bridge) whose _ADR returns 0x00020000 and the > +bus number of the parent PCI bridge is 0, the sysfs directory > +representing the struct acpi_device object created for that ACPI > +namespace object will contain the 'physical_node' symbolic link to the > +/sys/devices/pci0000:00/0000:00:02:0/ sysfs directory of the > +corresponding PCI device. > + > +The linking mechanism is generally bus-specific. The core of its > +implementation is located in the drivers/acpi/glue.c file, but there are > +complementary parts depending on the bus types in question located > +elsewhere. For example, the PCI-specific part of it is located in > +drivers/pci/pci-acpi.c. > + > + > +Example Linux ACPI Device Tree > +================================= > + > +The sysfs hierarchy of struct acpi_device objects corresponding to the > +example ACPI namespace illustrated in Figure 2 with the addition of > +fixed PWR_BUTTON/SLP_BUTTON devices is shown below:: > > +--------------+---+-----------------+ > | LNXSYSTEM:00 | \ | acpi:LNXSYSTEM: | > @@ -377,12 +385,14 @@ Wysocki <rafael.j.wysocki@xxxxxxxxx>. > > Figure 3. Example Linux ACPI Device Tree > > - NOTE: Each node is represented as "object/path/modalias", where: > - 1. 'object' is the name of the object's directory in sysfs. > - 2. 'path' is the ACPI namespace path of the corresponding > - ACPI namespace object, as returned by the object's 'path' > - sysfs attribute. > - 3. 'modalias' is the value of the object's 'modalias' sysfs > - attribute (as described earlier in this document). > - NOTE: N/A indicates the device object does not have the 'path' or the > - 'modalias' attribute. > +.. note:: Each node is represented as "object/path/modalias", where: > + > + 1. 'object' is the name of the object's directory in sysfs. > + 2. 'path' is the ACPI namespace path of the corresponding > + ACPI namespace object, as returned by the object's 'path' > + sysfs attribute. > + 3. 'modalias' is the value of the object's 'modalias' sysfs > + attribute (as described earlier in this document). > + > +.. note:: N/A indicates the device object does not have the 'path' or the > + 'modalias' attribute. Thanks, Mauro