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-rw-r--r--Documentation/arch/powerpc/booting.rst4
-rw-r--r--Documentation/arch/powerpc/cpu_families.rst18
-rw-r--r--Documentation/arch/powerpc/cxl.rst469
-rw-r--r--Documentation/arch/powerpc/cxlflash.rst433
-rw-r--r--Documentation/arch/powerpc/dexcr.rst141
-rw-r--r--Documentation/arch/powerpc/elf_hwcaps.rst1
-rw-r--r--Documentation/arch/powerpc/firmware-assisted-dump.rst113
-rw-r--r--Documentation/arch/powerpc/htm.rst104
-rw-r--r--Documentation/arch/powerpc/index.rst2
-rw-r--r--Documentation/arch/powerpc/kvm-nested.rst44
-rw-r--r--Documentation/arch/powerpc/papr_hcalls.rst11
-rw-r--r--Documentation/arch/powerpc/ultravisor.rst2
12 files changed, 355 insertions, 987 deletions
diff --git a/Documentation/arch/powerpc/booting.rst b/Documentation/arch/powerpc/booting.rst
index 11aa440f98cc..472e97891aef 100644
--- a/Documentation/arch/powerpc/booting.rst
+++ b/Documentation/arch/powerpc/booting.rst
@@ -93,8 +93,8 @@ given platform based on the content of the device-tree. Thus, you
should:
a) add your platform support as a _boolean_ option in
- arch/powerpc/Kconfig, following the example of PPC_PSERIES,
- PPC_PMAC and PPC_MAPLE. The latter is probably a good
+ arch/powerpc/Kconfig, following the example of PPC_PSERIES
+ and PPC_PMAC. The latter is probably a good
example of a board support to start from.
b) create your main platform file as
diff --git a/Documentation/arch/powerpc/cpu_families.rst b/Documentation/arch/powerpc/cpu_families.rst
index eb7e60649b43..f55433c6b8f3 100644
--- a/Documentation/arch/powerpc/cpu_families.rst
+++ b/Documentation/arch/powerpc/cpu_families.rst
@@ -128,24 +128,6 @@ IBM BookE
- All 32 bit::
+--------------+
- | 401 |
- +--------------+
- |
- |
- v
- +--------------+
- | 403 |
- +--------------+
- |
- |
- v
- +--------------+
- | 405 |
- +--------------+
- |
- |
- v
- +--------------+
| 440 |
+--------------+
|
diff --git a/Documentation/arch/powerpc/cxl.rst b/Documentation/arch/powerpc/cxl.rst
deleted file mode 100644
index d2d77057610e..000000000000
--- a/Documentation/arch/powerpc/cxl.rst
+++ /dev/null
@@ -1,469 +0,0 @@
-====================================
-Coherent Accelerator Interface (CXL)
-====================================
-
-Introduction
-============
-
- The coherent accelerator interface is designed to allow the
- coherent connection of accelerators (FPGAs and other devices) to a
- POWER system. These devices need to adhere to the Coherent
- Accelerator Interface Architecture (CAIA).
-
- IBM refers to this as the Coherent Accelerator Processor Interface
- or CAPI. In the kernel it's referred to by the name CXL to avoid
- confusion with the ISDN CAPI subsystem.
-
- Coherent in this context means that the accelerator and CPUs can
- both access system memory directly and with the same effective
- addresses.
-
-
-Hardware overview
-=================
-
- ::
-
- POWER8/9 FPGA
- +----------+ +---------+
- | | | |
- | CPU | | AFU |
- | | | |
- | | | |
- | | | |
- +----------+ +---------+
- | PHB | | |
- | +------+ | PSL |
- | | CAPP |<------>| |
- +---+------+ PCIE +---------+
-
- The POWER8/9 chip has a Coherently Attached Processor Proxy (CAPP)
- unit which is part of the PCIe Host Bridge (PHB). This is managed
- by Linux by calls into OPAL. Linux doesn't directly program the
- CAPP.
-
- The FPGA (or coherently attached device) consists of two parts.
- The POWER Service Layer (PSL) and the Accelerator Function Unit
- (AFU). The AFU is used to implement specific functionality behind
- the PSL. The PSL, among other things, provides memory address
- translation services to allow each AFU direct access to userspace
- memory.
-
- The AFU is the core part of the accelerator (eg. the compression,
- crypto etc function). The kernel has no knowledge of the function
- of the AFU. Only userspace interacts directly with the AFU.
-
- The PSL provides the translation and interrupt services that the
- AFU needs. This is what the kernel interacts with. For example, if
- the AFU needs to read a particular effective address, it sends
- that address to the PSL, the PSL then translates it, fetches the
- data from memory and returns it to the AFU. If the PSL has a
- translation miss, it interrupts the kernel and the kernel services
- the fault. The context to which this fault is serviced is based on
- who owns that acceleration function.
-
- - POWER8 and PSL Version 8 are compliant to the CAIA Version 1.0.
- - POWER9 and PSL Version 9 are compliant to the CAIA Version 2.0.
-
- This PSL Version 9 provides new features such as:
-
- * Interaction with the nest MMU on the P9 chip.
- * Native DMA support.
- * Supports sending ASB_Notify messages for host thread wakeup.
- * Supports Atomic operations.
- * etc.
-
- Cards with a PSL9 won't work on a POWER8 system and cards with a
- PSL8 won't work on a POWER9 system.
-
-AFU Modes
-=========
-
- There are two programming modes supported by the AFU. Dedicated
- and AFU directed. AFU may support one or both modes.
-
- When using dedicated mode only one MMU context is supported. In
- this mode, only one userspace process can use the accelerator at
- time.
-
- When using AFU directed mode, up to 16K simultaneous contexts can
- be supported. This means up to 16K simultaneous userspace
- applications may use the accelerator (although specific AFUs may
- support fewer). In this mode, the AFU sends a 16 bit context ID
- with each of its requests. This tells the PSL which context is
- associated with each operation. If the PSL can't translate an
- operation, the ID can also be accessed by the kernel so it can
- determine the userspace context associated with an operation.
-
-
-MMIO space
-==========
-
- A portion of the accelerator MMIO space can be directly mapped
- from the AFU to userspace. Either the whole space can be mapped or
- just a per context portion. The hardware is self describing, hence
- the kernel can determine the offset and size of the per context
- portion.
-
-
-Interrupts
-==========
-
- AFUs may generate interrupts that are destined for userspace. These
- are received by the kernel as hardware interrupts and passed onto
- userspace by a read syscall documented below.
-
- Data storage faults and error interrupts are handled by the kernel
- driver.
-
-
-Work Element Descriptor (WED)
-=============================
-
- The WED is a 64-bit parameter passed to the AFU when a context is
- started. Its format is up to the AFU hence the kernel has no
- knowledge of what it represents. Typically it will be the
- effective address of a work queue or status block where the AFU
- and userspace can share control and status information.
-
-
-
-
-User API
-========
-
-1. AFU character devices
-^^^^^^^^^^^^^^^^^^^^^^^^
-
- For AFUs operating in AFU directed mode, two character device
- files will be created. /dev/cxl/afu0.0m will correspond to a
- master context and /dev/cxl/afu0.0s will correspond to a slave
- context. Master contexts have access to the full MMIO space an
- AFU provides. Slave contexts have access to only the per process
- MMIO space an AFU provides.
-
- For AFUs operating in dedicated process mode, the driver will
- only create a single character device per AFU called
- /dev/cxl/afu0.0d. This will have access to the entire MMIO space
- that the AFU provides (like master contexts in AFU directed).
-
- The types described below are defined in include/uapi/misc/cxl.h
-
- The following file operations are supported on both slave and
- master devices.
-
- A userspace library libcxl is available here:
-
- https://github.com/ibm-capi/libcxl
-
- This provides a C interface to this kernel API.
-
-open
-----
-
- Opens the device and allocates a file descriptor to be used with
- the rest of the API.
-
- A dedicated mode AFU only has one context and only allows the
- device to be opened once.
-
- An AFU directed mode AFU can have many contexts, the device can be
- opened once for each context that is available.
-
- When all available contexts are allocated the open call will fail
- and return -ENOSPC.
-
- Note:
- IRQs need to be allocated for each context, which may limit
- the number of contexts that can be created, and therefore
- how many times the device can be opened. The POWER8 CAPP
- supports 2040 IRQs and 3 are used by the kernel, so 2037 are
- left. If 1 IRQ is needed per context, then only 2037
- contexts can be allocated. If 4 IRQs are needed per context,
- then only 2037/4 = 509 contexts can be allocated.
-
-
-ioctl
------
-
- CXL_IOCTL_START_WORK:
- Starts the AFU context and associates it with the current
- process. Once this ioctl is successfully executed, all memory
- mapped into this process is accessible to this AFU context
- using the same effective addresses. No additional calls are
- required to map/unmap memory. The AFU memory context will be
- updated as userspace allocates and frees memory. This ioctl
- returns once the AFU context is started.
-
- Takes a pointer to a struct cxl_ioctl_start_work
-
- ::
-
- struct cxl_ioctl_start_work {
- __u64 flags;
- __u64 work_element_descriptor;
- __u64 amr;
- __s16 num_interrupts;
- __s16 reserved1;
- __s32 reserved2;
- __u64 reserved3;
- __u64 reserved4;
- __u64 reserved5;
- __u64 reserved6;
- };
-
- flags:
- Indicates which optional fields in the structure are
- valid.
-
- work_element_descriptor:
- The Work Element Descriptor (WED) is a 64-bit argument
- defined by the AFU. Typically this is an effective
- address pointing to an AFU specific structure
- describing what work to perform.
-
- amr:
- Authority Mask Register (AMR), same as the powerpc
- AMR. This field is only used by the kernel when the
- corresponding CXL_START_WORK_AMR value is specified in
- flags. If not specified the kernel will use a default
- value of 0.
-
- num_interrupts:
- Number of userspace interrupts to request. This field
- is only used by the kernel when the corresponding
- CXL_START_WORK_NUM_IRQS value is specified in flags.
- If not specified the minimum number required by the
- AFU will be allocated. The min and max number can be
- obtained from sysfs.
-
- reserved fields:
- For ABI padding and future extensions
-
- CXL_IOCTL_GET_PROCESS_ELEMENT:
- Get the current context id, also known as the process element.
- The value is returned from the kernel as a __u32.
-
-
-mmap
-----
-
- An AFU may have an MMIO space to facilitate communication with the
- AFU. If it does, the MMIO space can be accessed via mmap. The size
- and contents of this area are specific to the particular AFU. The
- size can be discovered via sysfs.
-
- In AFU directed mode, master contexts are allowed to map all of
- the MMIO space and slave contexts are allowed to only map the per
- process MMIO space associated with the context. In dedicated
- process mode the entire MMIO space can always be mapped.
-
- This mmap call must be done after the START_WORK ioctl.
-
- Care should be taken when accessing MMIO space. Only 32 and 64-bit
- accesses are supported by POWER8. Also, the AFU will be designed
- with a specific endianness, so all MMIO accesses should consider
- endianness (recommend endian(3) variants like: le64toh(),
- be64toh() etc). These endian issues equally apply to shared memory
- queues the WED may describe.
-
-
-read
-----
-
- Reads events from the AFU. Blocks if no events are pending
- (unless O_NONBLOCK is supplied). Returns -EIO in the case of an
- unrecoverable error or if the card is removed.
-
- read() will always return an integral number of events.
-
- The buffer passed to read() must be at least 4K bytes.
-
- The result of the read will be a buffer of one or more events,
- each event is of type struct cxl_event, of varying size::
-
- struct cxl_event {
- struct cxl_event_header header;
- union {
- struct cxl_event_afu_interrupt irq;
- struct cxl_event_data_storage fault;
- struct cxl_event_afu_error afu_error;
- };
- };
-
- The struct cxl_event_header is defined as
-
- ::
-
- struct cxl_event_header {
- __u16 type;
- __u16 size;
- __u16 process_element;
- __u16 reserved1;
- };
-
- type:
- This defines the type of event. The type determines how
- the rest of the event is structured. These types are
- described below and defined by enum cxl_event_type.
-
- size:
- This is the size of the event in bytes including the
- struct cxl_event_header. The start of the next event can
- be found at this offset from the start of the current
- event.
-
- process_element:
- Context ID of the event.
-
- reserved field:
- For future extensions and padding.
-
- If the event type is CXL_EVENT_AFU_INTERRUPT then the event
- structure is defined as
-
- ::
-
- struct cxl_event_afu_interrupt {
- __u16 flags;
- __u16 irq; /* Raised AFU interrupt number */
- __u32 reserved1;
- };
-
- flags:
- These flags indicate which optional fields are present
- in this struct. Currently all fields are mandatory.
-
- irq:
- The IRQ number sent by the AFU.
-
- reserved field:
- For future extensions and padding.
-
- If the event type is CXL_EVENT_DATA_STORAGE then the event
- structure is defined as
-
- ::
-
- struct cxl_event_data_storage {
- __u16 flags;
- __u16 reserved1;
- __u32 reserved2;
- __u64 addr;
- __u64 dsisr;
- __u64 reserved3;
- };
-
- flags:
- These flags indicate which optional fields are present in
- this struct. Currently all fields are mandatory.
-
- address:
- The address that the AFU unsuccessfully attempted to
- access. Valid accesses will be handled transparently by the
- kernel but invalid accesses will generate this event.
-
- dsisr:
- This field gives information on the type of fault. It is a
- copy of the DSISR from the PSL hardware when the address
- fault occurred. The form of the DSISR is as defined in the
- CAIA.
-
- reserved fields:
- For future extensions
-
- If the event type is CXL_EVENT_AFU_ERROR then the event structure
- is defined as
-
- ::
-
- struct cxl_event_afu_error {
- __u16 flags;
- __u16 reserved1;
- __u32 reserved2;
- __u64 error;
- };
-
- flags:
- These flags indicate which optional fields are present in
- this struct. Currently all fields are Mandatory.
-
- error:
- Error status from the AFU. Defined by the AFU.
-
- reserved fields:
- For future extensions and padding
-
-
-2. Card character device (powerVM guest only)
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
- In a powerVM guest, an extra character device is created for the
- card. The device is only used to write (flash) a new image on the
- FPGA accelerator. Once the image is written and verified, the
- device tree is updated and the card is reset to reload the updated
- image.
-
-open
-----
-
- Opens the device and allocates a file descriptor to be used with
- the rest of the API. The device can only be opened once.
-
-ioctl
------
-
-CXL_IOCTL_DOWNLOAD_IMAGE / CXL_IOCTL_VALIDATE_IMAGE:
- Starts and controls flashing a new FPGA image. Partial
- reconfiguration is not supported (yet), so the image must contain
- a copy of the PSL and AFU(s). Since an image can be quite large,
- the caller may have to iterate, splitting the image in smaller
- chunks.
-
- Takes a pointer to a struct cxl_adapter_image::
-
- struct cxl_adapter_image {
- __u64 flags;
- __u64 data;
- __u64 len_data;
- __u64 len_image;
- __u64 reserved1;
- __u64 reserved2;
- __u64 reserved3;
- __u64 reserved4;
- };
-
- flags:
- These flags indicate which optional fields are present in
- this struct. Currently all fields are mandatory.
-
- data:
- Pointer to a buffer with part of the image to write to the
- card.
-
- len_data:
- Size of the buffer pointed to by data.
-
- len_image:
- Full size of the image.
-
-
-Sysfs Class
-===========
-
- A cxl sysfs class is added under /sys/class/cxl to facilitate
- enumeration and tuning of the accelerators. Its layout is
- described in Documentation/ABI/testing/sysfs-class-cxl
-
-
-Udev rules
-==========
-
- The following udev rules could be used to create a symlink to the
- most logical chardev to use in any programming mode (afuX.Yd for
- dedicated, afuX.Ys for afu directed), since the API is virtually
- identical for each::
-
- SUBSYSTEM=="cxl", ATTRS{mode}=="dedicated_process", SYMLINK="cxl/%b"
- SUBSYSTEM=="cxl", ATTRS{mode}=="afu_directed", \
- KERNEL=="afu[0-9]*.[0-9]*s", SYMLINK="cxl/%b"
diff --git a/Documentation/arch/powerpc/cxlflash.rst b/Documentation/arch/powerpc/cxlflash.rst
deleted file mode 100644
index e8f488acfa41..000000000000
--- a/Documentation/arch/powerpc/cxlflash.rst
+++ /dev/null
@@ -1,433 +0,0 @@
-================================
-Coherent Accelerator (CXL) Flash
-================================
-
-Introduction
-============
-
- The IBM Power architecture provides support for CAPI (Coherent
- Accelerator Power Interface), which is available to certain PCIe slots
- on Power 8 systems. CAPI can be thought of as a special tunneling
- protocol through PCIe that allow PCIe adapters to look like special
- purpose co-processors which can read or write an application's
- memory and generate page faults. As a result, the host interface to
- an adapter running in CAPI mode does not require the data buffers to
- be mapped to the device's memory (IOMMU bypass) nor does it require
- memory to be pinned.
-
- On Linux, Coherent Accelerator (CXL) kernel services present CAPI
- devices as a PCI device by implementing a virtual PCI host bridge.
- This abstraction simplifies the infrastructure and programming
- model, allowing for drivers to look similar to other native PCI
- device drivers.
-
- CXL provides a mechanism by which user space applications can
- directly talk to a device (network or storage) bypassing the typical
- kernel/device driver stack. The CXL Flash Adapter Driver enables a
- user space application direct access to Flash storage.
-
- The CXL Flash Adapter Driver is a kernel module that sits in the
- SCSI stack as a low level device driver (below the SCSI disk and
- protocol drivers) for the IBM CXL Flash Adapter. This driver is
- responsible for the initialization of the adapter, setting up the
- special path for user space access, and performing error recovery. It
- communicates directly the Flash Accelerator Functional Unit (AFU)
- as described in Documentation/arch/powerpc/cxl.rst.
-
- The cxlflash driver supports two, mutually exclusive, modes of
- operation at the device (LUN) level:
-
- - Any flash device (LUN) can be configured to be accessed as a
- regular disk device (i.e.: /dev/sdc). This is the default mode.
-
- - Any flash device (LUN) can be configured to be accessed from
- user space with a special block library. This mode further
- specifies the means of accessing the device and provides for
- either raw access to the entire LUN (referred to as direct
- or physical LUN access) or access to a kernel/AFU-mediated
- partition of the LUN (referred to as virtual LUN access). The
- segmentation of a disk device into virtual LUNs is assisted
- by special translation services provided by the Flash AFU.
-
-Overview
-========
-
- The Coherent Accelerator Interface Architecture (CAIA) introduces a
- concept of a master context. A master typically has special privileges
- granted to it by the kernel or hypervisor allowing it to perform AFU
- wide management and control. The master may or may not be involved
- directly in each user I/O, but at the minimum is involved in the
- initial setup before the user application is allowed to send requests
- directly to the AFU.
-
- The CXL Flash Adapter Driver establishes a master context with the
- AFU. It uses memory mapped I/O (MMIO) for this control and setup. The
- Adapter Problem Space Memory Map looks like this::
-
- +-------------------------------+
- | 512 * 64 KB User MMIO |
- | (per context) |
- | User Accessible |
- +-------------------------------+
- | 512 * 128 B per context |
- | Provisioning and Control |
- | Trusted Process accessible |
- +-------------------------------+
- | 64 KB Global |
- | Trusted Process accessible |
- +-------------------------------+
-
- This driver configures itself into the SCSI software stack as an
- adapter driver. The driver is the only entity that is considered a
- Trusted Process to program the Provisioning and Control and Global
- areas in the MMIO Space shown above. The master context driver
- discovers all LUNs attached to the CXL Flash adapter and instantiates
- scsi block devices (/dev/sdb, /dev/sdc etc.) for each unique LUN
- seen from each path.
-
- Once these scsi block devices are instantiated, an application
- written to a specification provided by the block library may get
- access to the Flash from user space (without requiring a system call).
-
- This master context driver also provides a series of ioctls for this
- block library to enable this user space access. The driver supports
- two modes for accessing the block device.
-
- The first mode is called a virtual mode. In this mode a single scsi
- block device (/dev/sdb) may be carved up into any number of distinct
- virtual LUNs. The virtual LUNs may be resized as long as the sum of
- the sizes of all the virtual LUNs, along with the meta-data associated
- with it does not exceed the physical capacity.
-
- The second mode is called the physical mode. In this mode a single
- block device (/dev/sdb) may be opened directly by the block library
- and the entire space for the LUN is available to the application.
-
- Only the physical mode provides persistence of the data. i.e. The
- data written to the block device will survive application exit and
- restart and also reboot. The virtual LUNs do not persist (i.e. do
- not survive after the application terminates or the system reboots).
-
-
-Block library API
-=================
-
- Applications intending to get access to the CXL Flash from user
- space should use the block library, as it abstracts the details of
- interfacing directly with the cxlflash driver that are necessary for
- performing administrative actions (i.e.: setup, tear down, resize).
- The block library can be thought of as a 'user' of services,
- implemented as IOCTLs, that are provided by the cxlflash driver
- specifically for devices (LUNs) operating in user space access
- mode. While it is not a requirement that applications understand
- the interface between the block library and the cxlflash driver,
- a high-level overview of each supported service (IOCTL) is provided
- below.
-
- The block library can be found on GitHub:
- http://github.com/open-power/capiflash
-
-
-CXL Flash Driver LUN IOCTLs
-===========================
-
- Users, such as the block library, that wish to interface with a flash
- device (LUN) via user space access need to use the services provided
- by the cxlflash driver. As these services are implemented as ioctls,
- a file descriptor handle must first be obtained in order to establish
- the communication channel between a user and the kernel. This file
- descriptor is obtained by opening the device special file associated
- with the scsi disk device (/dev/sdb) that was created during LUN
- discovery. As per the location of the cxlflash driver within the
- SCSI protocol stack, this open is actually not seen by the cxlflash
- driver. Upon successful open, the user receives a file descriptor
- (herein referred to as fd1) that should be used for issuing the
- subsequent ioctls listed below.
-
- The structure definitions for these IOCTLs are available in:
- uapi/scsi/cxlflash_ioctl.h
-
-DK_CXLFLASH_ATTACH
-------------------
-
- This ioctl obtains, initializes, and starts a context using the CXL
- kernel services. These services specify a context id (u16) by which
- to uniquely identify the context and its allocated resources. The
- services additionally provide a second file descriptor (herein
- referred to as fd2) that is used by the block library to initiate
- memory mapped I/O (via mmap()) to the CXL flash device and poll for
- completion events. This file descriptor is intentionally installed by
- this driver and not the CXL kernel services to allow for intermediary
- notification and access in the event of a non-user-initiated close(),
- such as a killed process. This design point is described in further
- detail in the description for the DK_CXLFLASH_DETACH ioctl.
-
- There are a few important aspects regarding the "tokens" (context id
- and fd2) that are provided back to the user:
-
- - These tokens are only valid for the process under which they
- were created. The child of a forked process cannot continue
- to use the context id or file descriptor created by its parent
- (see DK_CXLFLASH_VLUN_CLONE for further details).
-
- - These tokens are only valid for the lifetime of the context and
- the process under which they were created. Once either is
- destroyed, the tokens are to be considered stale and subsequent
- usage will result in errors.
-
- - A valid adapter file descriptor (fd2 >= 0) is only returned on
- the initial attach for a context. Subsequent attaches to an
- existing context (DK_CXLFLASH_ATTACH_REUSE_CONTEXT flag present)
- do not provide the adapter file descriptor as it was previously
- made known to the application.
-
- - When a context is no longer needed, the user shall detach from
- the context via the DK_CXLFLASH_DETACH ioctl. When this ioctl
- returns with a valid adapter file descriptor and the return flag
- DK_CXLFLASH_APP_CLOSE_ADAP_FD is present, the application _must_
- close the adapter file descriptor following a successful detach.
-
- - When this ioctl returns with a valid fd2 and the return flag
- DK_CXLFLASH_APP_CLOSE_ADAP_FD is present, the application _must_
- close fd2 in the following circumstances:
-
- + Following a successful detach of the last user of the context
- + Following a successful recovery on the context's original fd2
- + In the child process of a fork(), following a clone ioctl,
- on the fd2 associated with the source context
-
- - At any time, a close on fd2 will invalidate the tokens. Applications
- should exercise caution to only close fd2 when appropriate (outlined
- in the previous bullet) to avoid premature loss of I/O.
-
-DK_CXLFLASH_USER_DIRECT
------------------------
- This ioctl is responsible for transitioning the LUN to direct
- (physical) mode access and configuring the AFU for direct access from
- user space on a per-context basis. Additionally, the block size and
- last logical block address (LBA) are returned to the user.
-
- As mentioned previously, when operating in user space access mode,
- LUNs may be accessed in whole or in part. Only one mode is allowed
- at a time and if one mode is active (outstanding references exist),
- requests to use the LUN in a different mode are denied.
-
- The AFU is configured for direct access from user space by adding an
- entry to the AFU's resource handle table. The index of the entry is
- treated as a resource handle that is returned to the user. The user
- is then able to use the handle to reference the LUN during I/O.
-
-DK_CXLFLASH_USER_VIRTUAL
-------------------------
- This ioctl is responsible for transitioning the LUN to virtual mode
- of access and configuring the AFU for virtual access from user space
- on a per-context basis. Additionally, the block size and last logical
- block address (LBA) are returned to the user.
-
- As mentioned previously, when operating in user space access mode,
- LUNs may be accessed in whole or in part. Only one mode is allowed
- at a time and if one mode is active (outstanding references exist),
- requests to use the LUN in a different mode are denied.
-
- The AFU is configured for virtual access from user space by adding
- an entry to the AFU's resource handle table. The index of the entry
- is treated as a resource handle that is returned to the user. The
- user is then able to use the handle to reference the LUN during I/O.
-
- By default, the virtual LUN is created with a size of 0. The user
- would need to use the DK_CXLFLASH_VLUN_RESIZE ioctl to adjust the grow
- the virtual LUN to a desired size. To avoid having to perform this
- resize for the initial creation of the virtual LUN, the user has the
- option of specifying a size as part of the DK_CXLFLASH_USER_VIRTUAL
- ioctl, such that when success is returned to the user, the
- resource handle that is provided is already referencing provisioned
- storage. This is reflected by the last LBA being a non-zero value.
-
- When a LUN is accessible from more than one port, this ioctl will
- return with the DK_CXLFLASH_ALL_PORTS_ACTIVE return flag set. This
- provides the user with a hint that I/O can be retried in the event
- of an I/O error as the LUN can be reached over multiple paths.
-
-DK_CXLFLASH_VLUN_RESIZE
------------------------
- This ioctl is responsible for resizing a previously created virtual
- LUN and will fail if invoked upon a LUN that is not in virtual
- mode. Upon success, an updated last LBA is returned to the user
- indicating the new size of the virtual LUN associated with the
- resource handle.
-
- The partitioning of virtual LUNs is jointly mediated by the cxlflash
- driver and the AFU. An allocation table is kept for each LUN that is
- operating in the virtual mode and used to program a LUN translation
- table that the AFU references when provided with a resource handle.
-
- This ioctl can return -EAGAIN if an AFU sync operation takes too long.
- In addition to returning a failure to user, cxlflash will also schedule
- an asynchronous AFU reset. Should the user choose to retry the operation,
- it is expected to succeed. If this ioctl fails with -EAGAIN, the user
- can either retry the operation or treat it as a failure.
-
-DK_CXLFLASH_RELEASE
--------------------
- This ioctl is responsible for releasing a previously obtained
- reference to either a physical or virtual LUN. This can be
- thought of as the inverse of the DK_CXLFLASH_USER_DIRECT or
- DK_CXLFLASH_USER_VIRTUAL ioctls. Upon success, the resource handle
- is no longer valid and the entry in the resource handle table is
- made available to be used again.
-
- As part of the release process for virtual LUNs, the virtual LUN
- is first resized to 0 to clear out and free the translation tables
- associated with the virtual LUN reference.
-
-DK_CXLFLASH_DETACH
-------------------
- This ioctl is responsible for unregistering a context with the
- cxlflash driver and release outstanding resources that were
- not explicitly released via the DK_CXLFLASH_RELEASE ioctl. Upon
- success, all "tokens" which had been provided to the user from the
- DK_CXLFLASH_ATTACH onward are no longer valid.
-
- When the DK_CXLFLASH_APP_CLOSE_ADAP_FD flag was returned on a successful
- attach, the application _must_ close the fd2 associated with the context
- following the detach of the final user of the context.
-
-DK_CXLFLASH_VLUN_CLONE
-----------------------
- This ioctl is responsible for cloning a previously created
- context to a more recently created context. It exists solely to
- support maintaining user space access to storage after a process
- forks. Upon success, the child process (which invoked the ioctl)
- will have access to the same LUNs via the same resource handle(s)
- as the parent, but under a different context.
-
- Context sharing across processes is not supported with CXL and
- therefore each fork must be met with establishing a new context
- for the child process. This ioctl simplifies the state management
- and playback required by a user in such a scenario. When a process
- forks, child process can clone the parents context by first creating
- a context (via DK_CXLFLASH_ATTACH) and then using this ioctl to
- perform the clone from the parent to the child.
-
- The clone itself is fairly simple. The resource handle and lun
- translation tables are copied from the parent context to the child's
- and then synced with the AFU.
-
- When the DK_CXLFLASH_APP_CLOSE_ADAP_FD flag was returned on a successful
- attach, the application _must_ close the fd2 associated with the source
- context (still resident/accessible in the parent process) following the
- clone. This is to avoid a stale entry in the file descriptor table of the
- child process.
-
- This ioctl can return -EAGAIN if an AFU sync operation takes too long.
- In addition to returning a failure to user, cxlflash will also schedule
- an asynchronous AFU reset. Should the user choose to retry the operation,
- it is expected to succeed. If this ioctl fails with -EAGAIN, the user
- can either retry the operation or treat it as a failure.
-
-DK_CXLFLASH_VERIFY
-------------------
- This ioctl is used to detect various changes such as the capacity of
- the disk changing, the number of LUNs visible changing, etc. In cases
- where the changes affect the application (such as a LUN resize), the
- cxlflash driver will report the changed state to the application.
-
- The user calls in when they want to validate that a LUN hasn't been
- changed in response to a check condition. As the user is operating out
- of band from the kernel, they will see these types of events without
- the kernel's knowledge. When encountered, the user's architected
- behavior is to call in to this ioctl, indicating what they want to
- verify and passing along any appropriate information. For now, only
- verifying a LUN change (ie: size different) with sense data is
- supported.
-
-DK_CXLFLASH_RECOVER_AFU
------------------------
- This ioctl is used to drive recovery (if such an action is warranted)
- of a specified user context. Any state associated with the user context
- is re-established upon successful recovery.
-
- User contexts are put into an error condition when the device needs to
- be reset or is terminating. Users are notified of this error condition
- by seeing all 0xF's on an MMIO read. Upon encountering this, the
- architected behavior for a user is to call into this ioctl to recover
- their context. A user may also call into this ioctl at any time to
- check if the device is operating normally. If a failure is returned
- from this ioctl, the user is expected to gracefully clean up their
- context via release/detach ioctls. Until they do, the context they
- hold is not relinquished. The user may also optionally exit the process
- at which time the context/resources they held will be freed as part of
- the release fop.
-
- When the DK_CXLFLASH_APP_CLOSE_ADAP_FD flag was returned on a successful
- attach, the application _must_ unmap and close the fd2 associated with the
- original context following this ioctl returning success and indicating that
- the context was recovered (DK_CXLFLASH_RECOVER_AFU_CONTEXT_RESET).
-
-DK_CXLFLASH_MANAGE_LUN
-----------------------
- This ioctl is used to switch a LUN from a mode where it is available
- for file-system access (legacy), to a mode where it is set aside for
- exclusive user space access (superpipe). In case a LUN is visible
- across multiple ports and adapters, this ioctl is used to uniquely
- identify each LUN by its World Wide Node Name (WWNN).
-
-
-CXL Flash Driver Host IOCTLs
-============================
-
- Each host adapter instance that is supported by the cxlflash driver
- has a special character device associated with it to enable a set of
- host management function. These character devices are hosted in a
- class dedicated for cxlflash and can be accessed via `/dev/cxlflash/*`.
-
- Applications can be written to perform various functions using the
- host ioctl APIs below.
-
- The structure definitions for these IOCTLs are available in:
- uapi/scsi/cxlflash_ioctl.h
-
-HT_CXLFLASH_LUN_PROVISION
--------------------------
- This ioctl is used to create and delete persistent LUNs on cxlflash
- devices that lack an external LUN management interface. It is only
- valid when used with AFUs that support the LUN provision capability.
-
- When sufficient space is available, LUNs can be created by specifying
- the target port to host the LUN and a desired size in 4K blocks. Upon
- success, the LUN ID and WWID of the created LUN will be returned and
- the SCSI bus can be scanned to detect the change in LUN topology. Note
- that partial allocations are not supported. Should a creation fail due
- to a space issue, the target port can be queried for its current LUN
- geometry.
-
- To remove a LUN, the device must first be disassociated from the Linux
- SCSI subsystem. The LUN deletion can then be initiated by specifying a
- target port and LUN ID. Upon success, the LUN geometry associated with
- the port will be updated to reflect new number of provisioned LUNs and
- available capacity.
-
- To query the LUN geometry of a port, the target port is specified and
- upon success, the following information is presented:
-
- - Maximum number of provisioned LUNs allowed for the port
- - Current number of provisioned LUNs for the port
- - Maximum total capacity of provisioned LUNs for the port (4K blocks)
- - Current total capacity of provisioned LUNs for the port (4K blocks)
-
- With this information, the number of available LUNs and capacity can be
- can be calculated.
-
-HT_CXLFLASH_AFU_DEBUG
----------------------
- This ioctl is used to debug AFUs by supporting a command pass-through
- interface. It is only valid when used with AFUs that support the AFU
- debug capability.
-
- With exception of buffer management, AFU debug commands are opaque to
- cxlflash and treated as pass-through. For debug commands that do require
- data transfer, the user supplies an adequately sized data buffer and must
- specify the data transfer direction with respect to the host. There is a
- maximum transfer size of 256K imposed. Note that partial read completions
- are not supported - when errors are experienced with a host read data
- transfer, the data buffer is not copied back to the user.
diff --git a/Documentation/arch/powerpc/dexcr.rst b/Documentation/arch/powerpc/dexcr.rst
index 615a631f51fa..ab0724212fcd 100644
--- a/Documentation/arch/powerpc/dexcr.rst
+++ b/Documentation/arch/powerpc/dexcr.rst
@@ -36,8 +36,145 @@ state for a process.
Configuration
=============
-The DEXCR is currently unconfigurable. All threads are run with the
-NPHIE aspect enabled.
+prctl
+-----
+
+A process can control its own userspace DEXCR value using the
+``PR_PPC_GET_DEXCR`` and ``PR_PPC_SET_DEXCR`` pair of
+:manpage:`prctl(2)` commands. These calls have the form::
+
+ prctl(PR_PPC_GET_DEXCR, unsigned long which, 0, 0, 0);
+ prctl(PR_PPC_SET_DEXCR, unsigned long which, unsigned long ctrl, 0, 0);
+
+The possible 'which' and 'ctrl' values are as follows. Note there is no relation
+between the 'which' value and the DEXCR aspect's index.
+
+.. flat-table::
+ :header-rows: 1
+ :widths: 2 7 1
+
+ * - ``prctl()`` which
+ - Aspect name
+ - Aspect index
+
+ * - ``PR_PPC_DEXCR_SBHE``
+ - Speculative Branch Hint Enable (SBHE)
+ - 0
+
+ * - ``PR_PPC_DEXCR_IBRTPD``
+ - Indirect Branch Recurrent Target Prediction Disable (IBRTPD)
+ - 3
+
+ * - ``PR_PPC_DEXCR_SRAPD``
+ - Subroutine Return Address Prediction Disable (SRAPD)
+ - 4
+
+ * - ``PR_PPC_DEXCR_NPHIE``
+ - Non-Privileged Hash Instruction Enable (NPHIE)
+ - 5
+
+.. flat-table::
+ :header-rows: 1
+ :widths: 2 8
+
+ * - ``prctl()`` ctrl
+ - Meaning
+
+ * - ``PR_PPC_DEXCR_CTRL_EDITABLE``
+ - This aspect can be configured with PR_PPC_SET_DEXCR (get only)
+
+ * - ``PR_PPC_DEXCR_CTRL_SET``
+ - This aspect is set / set this aspect
+
+ * - ``PR_PPC_DEXCR_CTRL_CLEAR``
+ - This aspect is clear / clear this aspect
+
+ * - ``PR_PPC_DEXCR_CTRL_SET_ONEXEC``
+ - This aspect will be set after exec / set this aspect after exec
+
+ * - ``PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC``
+ - This aspect will be clear after exec / clear this aspect after exec
+
+Note that
+
+* which is a plain value, not a bitmask. Aspects must be worked with individually.
+
+* ctrl is a bitmask. ``PR_PPC_GET_DEXCR`` returns both the current and onexec
+ configuration. For example, ``PR_PPC_GET_DEXCR`` may return
+ ``PR_PPC_DEXCR_CTRL_EDITABLE | PR_PPC_DEXCR_CTRL_SET |
+ PR_PPC_DEXCR_CTRL_CLEAR_ONEXEC``. This would indicate the aspect is currently
+ set, it will be cleared when you run exec, and you can change this with the
+ ``PR_PPC_SET_DEXCR`` prctl.
+
+* The set/clear terminology refers to setting/clearing the bit in the DEXCR.
+ For example::
+
+ prctl(PR_PPC_SET_DEXCR, PR_PPC_DEXCR_IBRTPD, PR_PPC_DEXCR_CTRL_SET, 0, 0);
+
+ will set the IBRTPD aspect bit in the DEXCR, causing indirect branch prediction
+ to be disabled.
+
+* The status returned by ``PR_PPC_GET_DEXCR`` represents what value the process
+ would like applied. It does not include any alternative overrides, such as if
+ the hypervisor is enforcing the aspect be set. To see the true DEXCR state
+ software should read the appropriate SPRs directly.
+
+* The aspect state when starting a process is copied from the parent's state on
+ :manpage:`fork(2)`. The state is reset to a fixed value on
+ :manpage:`execve(2)`. The PR_PPC_SET_DEXCR prctl() can control both of these
+ values.
+
+* The ``*_ONEXEC`` controls do not change the current process's DEXCR.
+
+Use ``PR_PPC_SET_DEXCR`` with one of ``PR_PPC_DEXCR_CTRL_SET`` or
+``PR_PPC_DEXCR_CTRL_CLEAR`` to edit a given aspect.
+
+Common error codes for both getting and setting the DEXCR are as follows:
+
+.. flat-table::
+ :header-rows: 1
+ :widths: 2 8
+
+ * - Error
+ - Meaning
+
+ * - ``EINVAL``
+ - The DEXCR is not supported by the kernel.
+
+ * - ``ENODEV``
+ - The aspect is not recognised by the kernel or not supported by the
+ hardware.
+
+``PR_PPC_SET_DEXCR`` may also report the following error codes:
+
+.. flat-table::
+ :header-rows: 1
+ :widths: 2 8
+
+ * - Error
+ - Meaning
+
+ * - ``EINVAL``
+ - The ctrl value contains unrecognised flags.
+
+ * - ``EINVAL``
+ - The ctrl value contains mutually conflicting flags (e.g.,
+ ``PR_PPC_DEXCR_CTRL_SET | PR_PPC_DEXCR_CTRL_CLEAR``)
+
+ * - ``EPERM``
+ - This aspect cannot be modified with prctl() (check for the
+ PR_PPC_DEXCR_CTRL_EDITABLE flag with PR_PPC_GET_DEXCR).
+
+ * - ``EPERM``
+ - The process does not have sufficient privilege to perform the operation.
+ For example, clearing NPHIE on exec is a privileged operation (a process
+ can still clear its own NPHIE aspect without privileges).
+
+This interface allows a process to control its own DEXCR aspects, and also set
+the initial DEXCR value for any children in its process tree (up to the next
+child to use an ``*_ONEXEC`` control). This allows fine-grained control over the
+default value of the DEXCR, for example allowing containers to run with different
+default values.
coredump and ptrace
diff --git a/Documentation/arch/powerpc/elf_hwcaps.rst b/Documentation/arch/powerpc/elf_hwcaps.rst
index 4c896cf077c2..fce7489877b5 100644
--- a/Documentation/arch/powerpc/elf_hwcaps.rst
+++ b/Documentation/arch/powerpc/elf_hwcaps.rst
@@ -91,6 +91,7 @@ PPC_FEATURE_HAS_MMU
PPC_FEATURE_HAS_4xxMAC
The processor is 40x or 44x family.
+ Unused in the kernel since 732b32daef80 ("powerpc: Remove core support for 40x")
PPC_FEATURE_UNIFIED_CACHE
The processor has a unified L1 cache for instructions and data, as
diff --git a/Documentation/arch/powerpc/firmware-assisted-dump.rst b/Documentation/arch/powerpc/firmware-assisted-dump.rst
index e363fc48529a..7e266e749cd5 100644
--- a/Documentation/arch/powerpc/firmware-assisted-dump.rst
+++ b/Documentation/arch/powerpc/firmware-assisted-dump.rst
@@ -120,6 +120,28 @@ to ensure that crash data is preserved to process later.
e.g.
# echo 1 > /sys/firmware/opal/mpipl/release_core
+-- Support for Additional Kernel Arguments in Fadump
+ Fadump has a feature that allows passing additional kernel arguments
+ to the fadump kernel. This feature was primarily designed to disable
+ kernel functionalities that are not required for the fadump kernel
+ and to reduce its memory footprint while collecting the dump.
+
+ Command to Add Additional Kernel Parameters to Fadump:
+ e.g.
+ # echo "nr_cpus=16" > /sys/kernel/fadump/bootargs_append
+
+ The above command is sufficient to add additional arguments to fadump.
+ An explicit service restart is not required.
+
+ Command to Retrieve the Additional Fadump Arguments:
+ e.g.
+ # cat /sys/kernel/fadump/bootargs_append
+
+Note: Additional kernel arguments for fadump with HASH MMU is only
+ supported if the RMA size is greater than 768 MB. If the RMA
+ size is less than 768 MB, the kernel does not export the
+ /sys/kernel/fadump/bootargs_append sysfs node.
+
Implementation details:
-----------------------
@@ -134,12 +156,12 @@ that are run. If there is dump data, then the
memory is held.
If there is no waiting dump data, then only the memory required to
-hold CPU state, HPTE region, boot memory dump, FADump header and
-elfcore header, is usually reserved at an offset greater than boot
-memory size (see Fig. 1). This area is *not* released: this region
-will be kept permanently reserved, so that it can act as a receptacle
-for a copy of the boot memory content in addition to CPU state and
-HPTE region, in the case a crash does occur.
+hold CPU state, HPTE region, boot memory dump, and FADump header is
+usually reserved at an offset greater than boot memory size (see Fig. 1).
+This area is *not* released: this region will be kept permanently
+reserved, so that it can act as a receptacle for a copy of the boot
+memory content in addition to CPU state and HPTE region, in the case
+a crash does occur.
Since this reserved memory area is used only after the system crash,
there is no point in blocking this significant chunk of memory from
@@ -153,22 +175,22 @@ that were present in CMA region::
o Memory Reservation during first kernel
- Low memory Top of memory
- 0 boot memory size |<--- Reserved dump area --->| |
- | | | Permanent Reservation | |
- V V | | V
- +-----------+-----/ /---+---+----+-------+-----+-----+----+--+
- | | |///|////| DUMP | HDR | ELF |////| |
- +-----------+-----/ /---+---+----+-------+-----+-----+----+--+
- | ^ ^ ^ ^ ^
- | | | | | |
- \ CPU HPTE / | |
- ------------------------------ | |
- Boot memory content gets transferred | |
- to reserved area by firmware at the | |
- time of crash. | |
- FADump Header |
- (meta area) |
+ Low memory Top of memory
+ 0 boot memory size |<------ Reserved dump area ----->| |
+ | | | Permanent Reservation | |
+ V V | | V
+ +-----------+-----/ /---+---+----+-----------+-------+----+-----+
+ | | |///|////| DUMP | HDR |////| |
+ +-----------+-----/ /---+---+----+-----------+-------+----+-----+
+ | ^ ^ ^ ^ ^
+ | | | | | |
+ \ CPU HPTE / | |
+ -------------------------------- | |
+ Boot memory content gets transferred | |
+ to reserved area by firmware at the | |
+ time of crash. | |
+ FADump Header |
+ (meta area) |
|
|
Metadata: This area holds a metadata structure whose
@@ -186,13 +208,20 @@ that were present in CMA region::
0 boot memory size |
| |<------------ Crash preserved area ------------>|
V V |<--- Reserved dump area --->| |
- +-----------+-----/ /---+---+----+-------+-----+-----+----+--+
- | | |///|////| DUMP | HDR | ELF |////| |
- +-----------+-----/ /---+---+----+-------+-----+-----+----+--+
- | |
- V V
- Used by second /proc/vmcore
- kernel to boot
+ +----+---+--+-----/ /---+---+----+-------+-----+-----+-------+
+ | |ELF| | |///|////| DUMP | HDR |/////| |
+ +----+---+--+-----/ /---+---+----+-------+-----+-----+-------+
+ | | | | | |
+ ----- ------------------------------ ---------------
+ \ | |
+ \ | |
+ \ | |
+ \ | ----------------------------
+ \ | /
+ \ | /
+ \ | /
+ /proc/vmcore
+
+---+
|///| -> Regions (CPU, HPTE & Metadata) marked like this in the above
@@ -200,6 +229,12 @@ that were present in CMA region::
does not have CPU & HPTE regions while Metadata region is
not supported on pSeries currently.
+ +---+
+ |ELF| -> elfcorehdr, it is created in second kernel after crash.
+ +---+
+
+ Note: Memory from 0 to the boot memory size is used by second kernel
+
Fig. 2
@@ -353,26 +388,6 @@ TODO:
- Need to come up with the better approach to find out more
accurate boot memory size that is required for a kernel to
boot successfully when booted with restricted memory.
- - The FADump implementation introduces a FADump crash info structure
- in the scratch area before the ELF core header. The idea of introducing
- this structure is to pass some important crash info data to the second
- kernel which will help second kernel to populate ELF core header with
- correct data before it gets exported through /proc/vmcore. The current
- design implementation does not address a possibility of introducing
- additional fields (in future) to this structure without affecting
- compatibility. Need to come up with the better approach to address this.
-
- The possible approaches are:
-
- 1. Introduce version field for version tracking, bump up the version
- whenever a new field is added to the structure in future. The version
- field can be used to find out what fields are valid for the current
- version of the structure.
- 2. Reserve the area of predefined size (say PAGE_SIZE) for this
- structure and have unused area as reserved (initialized to zero)
- for future field additions.
-
- The advantage of approach 1 over 2 is we don't need to reserve extra space.
Author: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
diff --git a/Documentation/arch/powerpc/htm.rst b/Documentation/arch/powerpc/htm.rst
new file mode 100644
index 000000000000..fcb4eb6306b1
--- /dev/null
+++ b/Documentation/arch/powerpc/htm.rst
@@ -0,0 +1,104 @@
+.. SPDX-License-Identifier: GPL-2.0
+.. _htm:
+
+===================================
+HTM (Hardware Trace Macro)
+===================================
+
+Athira Rajeev, 2 Mar 2025
+
+.. contents::
+ :depth: 3
+
+
+Basic overview
+==============
+
+H_HTM is used as an interface for executing Hardware Trace Macro (HTM)
+functions, including setup, configuration, control and dumping of the HTM data.
+For using HTM, it is required to setup HTM buffers and HTM operations can
+be controlled using the H_HTM hcall. The hcall can be invoked for any core/chip
+of the system from within a partition itself. To use this feature, a debugfs
+folder called "htmdump" is present under /sys/kernel/debug/powerpc.
+
+
+HTM debugfs example usage
+=========================
+
+.. code-block:: sh
+
+ # ls /sys/kernel/debug/powerpc/htmdump/
+ coreindexonchip htmcaps htmconfigure htmflags htminfo htmsetup
+ htmstart htmstatus htmtype nodalchipindex nodeindex trace
+
+Details on each file:
+
+* nodeindex, nodalchipindex, coreindexonchip specifies which partition to configure the HTM for.
+* htmtype: specifies the type of HTM. Supported target is hardwareTarget.
+* trace: is to read the HTM data.
+* htmconfigure: Configure/Deconfigure the HTM. Writing 1 to the file will configure the trace, writing 0 to the file will do deconfigure.
+* htmstart: start/Stop the HTM. Writing 1 to the file will start the tracing, writing 0 to the file will stop the tracing.
+* htmstatus: get the status of HTM. This is needed to understand the HTM state after each operation.
+* htmsetup: set the HTM buffer size. Size of HTM buffer is in power of 2
+* htminfo: provides the system processor configuration details. This is needed to understand the appropriate values for nodeindex, nodalchipindex, coreindexonchip.
+* htmcaps : provides the HTM capabilities like minimum/maximum buffer size, what kind of tracing the HTM supports etc.
+* htmflags : allows to pass flags to hcall. Currently supports controlling the wrapping of HTM buffer.
+
+To see the system processor configuration details:
+
+.. code-block:: sh
+
+ # cat /sys/kernel/debug/powerpc/htmdump/htminfo > htminfo_file
+
+The result can be interpreted using hexdump.
+
+To collect HTM traces for a partition represented by nodeindex as
+zero, nodalchipindex as 1 and coreindexonchip as 12
+
+.. code-block:: sh
+
+ # cd /sys/kernel/debug/powerpc/htmdump/
+ # echo 2 > htmtype
+ # echo 33 > htmsetup ( sets 8GB memory for HTM buffer, number is size in power of 2 )
+
+This requires a CEC reboot to get the HTM buffers allocated.
+
+.. code-block:: sh
+
+ # cd /sys/kernel/debug/powerpc/htmdump/
+ # echo 2 > htmtype
+ # echo 0 > nodeindex
+ # echo 1 > nodalchipindex
+ # echo 12 > coreindexonchip
+ # echo 1 > htmflags # to set noWrap for HTM buffers
+ # echo 1 > htmconfigure # Configure the HTM
+ # echo 1 > htmstart # Start the HTM
+ # echo 0 > htmstart # Stop the HTM
+ # echo 0 > htmconfigure # Deconfigure the HTM
+ # cat htmstatus # Dump the status of HTM entries as data
+
+Above will set the htmtype and core details, followed by executing respective HTM operation.
+
+Read the HTM trace data
+========================
+
+After starting the trace collection, run the workload
+of interest. Stop the trace collection after required period
+of time, and read the trace file.
+
+.. code-block:: sh
+
+ # cat /sys/kernel/debug/powerpc/htmdump/trace > trace_file
+
+This trace file will contain the relevant instruction traces
+collected during the workload execution. And can be used as
+input file for trace decoders to understand data.
+
+Benefits of using HTM debugfs interface
+=======================================
+
+It is now possible to collect traces for a particular core/chip
+from within any partition of the system and decode it. Through
+this enablement, a small partition can be dedicated to collect the
+trace data and analyze to provide important information for Performance
+analysis, Software tuning, or Hardware debug.
diff --git a/Documentation/arch/powerpc/index.rst b/Documentation/arch/powerpc/index.rst
index 9749f6dc258f..0560cbae5fa1 100644
--- a/Documentation/arch/powerpc/index.rst
+++ b/Documentation/arch/powerpc/index.rst
@@ -12,8 +12,6 @@ powerpc
bootwrapper
cpu_families
cpu_features
- cxl
- cxlflash
dawr-power9
dexcr
dscr
diff --git a/Documentation/arch/powerpc/kvm-nested.rst b/Documentation/arch/powerpc/kvm-nested.rst
index 630602a8aa00..574592505604 100644
--- a/Documentation/arch/powerpc/kvm-nested.rst
+++ b/Documentation/arch/powerpc/kvm-nested.rst
@@ -208,13 +208,9 @@ associated values for each ID in the GSB::
flags:
Bit 0: getGuestWideState: Request state of the Guest instead
of an individual VCPU.
- Bit 1: takeOwnershipOfVcpuState Indicate the L1 is taking
- over ownership of the VCPU state and that the L0 can free
- the storage holding the state. The VCPU state will need to
- be returned to the Hypervisor via H_GUEST_SET_STATE prior
- to H_GUEST_RUN_VCPU being called for this VCPU. The data
- returned in the dataBuffer is in a Hypervisor internal
- format.
+ Bit 1: getHostWideState: Request stats of the Host. This causes
+ the guestId and vcpuId parameters to be ignored and attempting
+ to get the VCPU/Guest state will cause an error.
Bits 2-63: Reserved
guestId: ID obtained from H_GUEST_CREATE
vcpuId: ID of the vCPU pass to H_GUEST_CREATE_VCPU
@@ -406,9 +402,10 @@ the partition like the timebase offset and partition scoped page
table information.
+--------+-------+----+--------+----------------------------------+
-| ID | Size | RW | Thread | Details |
-| | Bytes | | Guest | |
-| | | | Scope | |
+| ID | Size | RW |(H)ost | Details |
+| | Bytes | |(G)uest | |
+| | | |(T)hread| |
+| | | |Scope | |
+========+=======+====+========+==================================+
| 0x0000 | | RW | TG | NOP element |
+--------+-------+----+--------+----------------------------------+
@@ -434,6 +431,29 @@ table information.
| | | | |- 0x8 Table size. |
+--------+-------+----+--------+----------------------------------+
| 0x0007-| | | | Reserved |
+| 0x07FF | | | | |
++--------+-------+----+--------+----------------------------------+
+| 0x0800 | 0x08 | R | H | Current usage in bytes of the |
+| | | | | L0's Guest Management Space |
+| | | | | for an L1-Lpar. |
++--------+-------+----+--------+----------------------------------+
+| 0x0801 | 0x08 | R | H | Max bytes available in the |
+| | | | | L0's Guest Management Space for |
+| | | | | an L1-Lpar |
++--------+-------+----+--------+----------------------------------+
+| 0x0802 | 0x08 | R | H | Current usage in bytes of the |
+| | | | | L0's Guest Page Table Management |
+| | | | | Space for an L1-Lpar |
++--------+-------+----+--------+----------------------------------+
+| 0x0803 | 0x08 | R | H | Max bytes available in the L0's |
+| | | | | Guest Page Table Management |
+| | | | | Space for an L1-Lpar |
++--------+-------+----+--------+----------------------------------+
+| 0x0804 | 0x08 | R | H | Cumulative Reclaimed bytes from |
+| | | | | L0 Guest's Page Table Management |
+| | | | | Space due to overcommit |
++--------+-------+----+--------+----------------------------------+
+| 0x0805-| | | | Reserved |
| 0x0BFF | | | | |
+--------+-------+----+--------+----------------------------------+
| 0x0C00 | 0x10 | RW | T |Run vCPU Input Buffer: |
@@ -546,7 +566,9 @@ table information.
+--------+-------+----+--------+----------------------------------+
| 0x1052 | 0x08 | RW | T | CTRL |
+--------+-------+----+--------+----------------------------------+
-| 0x1053-| | | | Reserved |
+| 0x1053 | 0x08 | RW | T | DPDES |
++--------+-------+----+--------+----------------------------------+
+| 0x1054-| | | | Reserved |
| 0x1FFF | | | | |
+--------+-------+----+--------+----------------------------------+
| 0x2000 | 0x04 | RW | T | CR |
diff --git a/Documentation/arch/powerpc/papr_hcalls.rst b/Documentation/arch/powerpc/papr_hcalls.rst
index 80d2c0aadab5..805e1cb9bab9 100644
--- a/Documentation/arch/powerpc/papr_hcalls.rst
+++ b/Documentation/arch/powerpc/papr_hcalls.rst
@@ -289,6 +289,17 @@ to be issued multiple times in order to be completely serviced. The
subsequent hcalls to the hypervisor until the hcall is completely serviced
at which point H_SUCCESS or other error is returned by the hypervisor.
+**H_HTM**
+
+| Input: flags, target, operation (op), op-param1, op-param2, op-param3
+| Out: *dumphtmbufferdata*
+| Return Value: *H_Success,H_Busy,H_LongBusyOrder,H_Partial,H_Parameter,
+ H_P2,H_P3,H_P4,H_P5,H_P6,H_State,H_Not_Available,H_Authority*
+
+H_HTM supports setup, configuration, control and dumping of Hardware Trace
+Macro (HTM) function and its data. HTM buffer stores tracing data for functions
+like core instruction, core LLAT and nest.
+
References
==========
.. [1] "Power Architecture Platform Reference"
diff --git a/Documentation/arch/powerpc/ultravisor.rst b/Documentation/arch/powerpc/ultravisor.rst
index ba6b1bf1cc44..6d0407b2f5a1 100644
--- a/Documentation/arch/powerpc/ultravisor.rst
+++ b/Documentation/arch/powerpc/ultravisor.rst
@@ -134,7 +134,7 @@ Hardware
* PTCR and partition table entries (partition table is in secure
memory). An attempt to write to PTCR will cause a Hypervisor
- Emulation Assitance interrupt.
+ Emulation Assistance interrupt.
* LDBAR (LD Base Address Register) and IMC (In-Memory Collection)
non-architected registers. An attempt to write to them will cause a