docs: move riscv under arch

and fix all in-tree references.

Architecture-specific documentation is being moved into Documentation/arch/
as a way of cleaning up the top-level documentation directory and making
the docs hierarchy more closely match the source hierarchy.

Signed-off-by: Costa Shulyupin <costa.shul@redhat.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20230930185354.3034118-1-costa.shul@redhat.com

10 files changed, 0 insertions, 767 deletions

diff --git a/Documentation/riscv/acpi.rst b/Documentation/riscv/acpi.rst
deleted file mode 100644
index 9870a282815b..000000000000
--- a/Documentation/riscv/acpi.rst
+++ /dev/null
@@ -1,10 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-==============
-ACPI on RISC-V
-==============
-
-The ISA string parsing rules for ACPI are defined by `Version ASCIIDOC
-Conversion, 12/2022 of the RISC-V specifications, as defined by tag
-"riscv-isa-release-1239329-2023-05-23" (commit 1239329
-) <https://github.com/riscv/riscv-isa-manual/releases/tag/riscv-isa-release-1239329-2023-05-23>`_
diff --git a/Documentation/riscv/boot-image-header.rst b/Documentation/riscv/boot-image-header.rst
deleted file mode 100644
index df2ffc173e80..000000000000
--- a/Documentation/riscv/boot-image-header.rst
+++ /dev/null
@@ -1,59 +0,0 @@
-=================================
-Boot image header in RISC-V Linux
-=================================
-
-:Author: Atish Patra <atish.patra@wdc.com>
-:Date:   20 May 2019
-
-This document only describes the boot image header details for RISC-V Linux.
-
-The following 64-byte header is present in decompressed Linux kernel image::
-
-	u32 code0;		  /* Executable code */
-	u32 code1;		  /* Executable code */
-	u64 text_offset;	  /* Image load offset, little endian */
-	u64 image_size;		  /* Effective Image size, little endian */
-	u64 flags;		  /* kernel flags, little endian */
-	u32 version;		  /* Version of this header */
-	u32 res1 = 0;		  /* Reserved */
-	u64 res2 = 0;		  /* Reserved */
-	u64 magic = 0x5643534952; /* Magic number, little endian, "RISCV" */
-	u32 magic2 = 0x05435352;  /* Magic number 2, little endian, "RSC\x05" */
-	u32 res3;		  /* Reserved for PE COFF offset */
-
-This header format is compliant with PE/COFF header and largely inspired from
-ARM64 header. Thus, both ARM64 & RISC-V header can be combined into one common
-header in future.
-
-Notes
-=====
-
-- This header is also reused to support EFI stub for RISC-V. EFI specification
-  needs PE/COFF image header in the beginning of the kernel image in order to
-  load it as an EFI application. In order to support EFI stub, code0 is replaced
-  with "MZ" magic string and res3(at offset 0x3c) points to the rest of the
-  PE/COFF header.
-
-- version field indicate header version number
-
-	==========  =============
-	Bits 0:15   Minor version
-	Bits 16:31  Major version
-	==========  =============
-
-  This preserves compatibility across newer and older version of the header.
-  The current version is defined as 0.2.
-
-- The "magic" field is deprecated as of version 0.2.  In a future
-  release, it may be removed.  This originally should have matched up
-  with the ARM64 header "magic" field, but unfortunately does not.
-  The "magic2" field replaces it, matching up with the ARM64 header.
-
-- In current header, the flags field has only one field.
-
-	=====  ====================================
-	Bit 0  Kernel endianness. 1 if BE, 0 if LE.
-	=====  ====================================
-
-- Image size is mandatory for boot loader to load kernel image. Booting will
-  fail otherwise.
diff --git a/Documentation/riscv/boot.rst b/Documentation/riscv/boot.rst
deleted file mode 100644
index 6077b587a842..000000000000
--- a/Documentation/riscv/boot.rst
+++ /dev/null
@@ -1,169 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-===============================================
-RISC-V Kernel Boot Requirements and Constraints
-===============================================
-
-:Author: Alexandre Ghiti <alexghiti@rivosinc.com>
-:Date: 23 May 2023
-
-This document describes what the RISC-V kernel expects from bootloaders and
-firmware, and also the constraints that any developer must have in mind when
-touching the early boot process. For the purposes of this document, the
-``early boot process`` refers to any code that runs before the final virtual
-mapping is set up.
-
-Pre-kernel Requirements and Constraints
-=======================================
-
-The RISC-V kernel expects the following of bootloaders and platform firmware:
-
-Register state
---------------
-
-The RISC-V kernel expects:
-
-  * ``$a0`` to contain the hartid of the current core.
-  * ``$a1`` to contain the address of the devicetree in memory.
-
-CSR state
----------
-
-The RISC-V kernel expects:
-
-  * ``$satp = 0``: the MMU, if present, must be disabled.
-
-Reserved memory for resident firmware
--------------------------------------
-
-The RISC-V kernel must not map any resident memory, or memory protected with
-PMPs, in the direct mapping, so the firmware must correctly mark those regions
-as per the devicetree specification and/or the UEFI specification.
-
-Kernel location
----------------
-
-The RISC-V kernel expects to be placed at a PMD boundary (2MB aligned for rv64
-and 4MB aligned for rv32). Note that the EFI stub will physically relocate the
-kernel if that's not the case.
-
-Hardware description
---------------------
-
-The firmware can pass either a devicetree or ACPI tables to the RISC-V kernel.
-
-The devicetree is either passed directly to the kernel from the previous stage
-using the ``$a1`` register, or when booting with UEFI, it can be passed using the
-EFI configuration table.
-
-The ACPI tables are passed to the kernel using the EFI configuration table. In
-this case, a tiny devicetree is still created by the EFI stub. Please refer to
-"EFI stub and devicetree" section below for details about this devicetree.
-
-Kernel entry
-------------
-
-On SMP systems, there are 2 methods to enter the kernel:
-
-- ``RISCV_BOOT_SPINWAIT``: the firmware releases all harts in the kernel, one hart
-  wins a lottery and executes the early boot code while the other harts are
-  parked waiting for the initialization to finish. This method is mostly used to
-  support older firmwares without SBI HSM extension and M-mode RISC-V kernel.
-- ``Ordered booting``: the firmware releases only one hart that will execute the
-  initialization phase and then will start all other harts using the SBI HSM
-  extension. The ordered booting method is the preferred booting method for
-  booting the RISC-V kernel because it can support CPU hotplug and kexec.
-
-UEFI
-----
-
-UEFI memory map
-~~~~~~~~~~~~~~~
-
-When booting with UEFI, the RISC-V kernel will use only the EFI memory map to
-populate the system memory.
-
-The UEFI firmware must parse the subnodes of the ``/reserved-memory`` devicetree
-node and abide by the devicetree specification to convert the attributes of
-those subnodes (``no-map`` and ``reusable``) into their correct EFI equivalent
-(refer to section "3.5.4 /reserved-memory and UEFI" of the devicetree
-specification v0.4-rc1).
-
-RISCV_EFI_BOOT_PROTOCOL
-~~~~~~~~~~~~~~~~~~~~~~~
-
-When booting with UEFI, the EFI stub requires the boot hartid in order to pass
-it to the RISC-V kernel in ``$a1``. The EFI stub retrieves the boot hartid using
-one of the following methods:
-
-- ``RISCV_EFI_BOOT_PROTOCOL`` (**preferred**).
-- ``boot-hartid`` devicetree subnode (**deprecated**).
-
-Any new firmware must implement ``RISCV_EFI_BOOT_PROTOCOL`` as the devicetree
-based approach is deprecated now.
-
-Early Boot Requirements and Constraints
-=======================================
-
-The RISC-V kernel's early boot process operates under the following constraints:
-
-EFI stub and devicetree
------------------------
-
-When booting with UEFI, the devicetree is supplemented (or created) by the EFI
-stub with the same parameters as arm64 which are described at the paragraph
-"UEFI kernel support on ARM" in Documentation/arch/arm/uefi.rst.
-
-Virtual mapping installation
-----------------------------
-
-The installation of the virtual mapping is done in 2 steps in the RISC-V kernel:
-
-1. ``setup_vm()`` installs a temporary kernel mapping in ``early_pg_dir`` which
-   allows discovery of the system memory. Only the kernel text/data are mapped
-   at this point. When establishing this mapping, no allocation can be done
-   (since the system memory is not known yet), so ``early_pg_dir`` page table is
-   statically allocated (using only one table for each level).
-
-2. ``setup_vm_final()`` creates the final kernel mapping in ``swapper_pg_dir``
-   and takes advantage of the discovered system memory to create the linear
-   mapping. When establishing this mapping, the kernel can allocate memory but
-   cannot access it directly (since the direct mapping is not present yet), so
-   it uses temporary mappings in the fixmap region to be able to access the
-   newly allocated page table levels.
-
-For ``virt_to_phys()`` and ``phys_to_virt()`` to be able to correctly convert
-direct mapping addresses to physical addresses, they need to know the start of
-the DRAM. This happens after step 1, right before step 2 installs the direct
-mapping (see ``setup_bootmem()`` function in arch/riscv/mm/init.c). Any usage of
-those macros before the final virtual mapping is installed must be carefully
-examined.
-
-Devicetree mapping via fixmap
------------------------------
-
-As the ``reserved_mem`` array is initialized with virtual addresses established
-by ``setup_vm()``, and used with the mapping established by
-``setup_vm_final()``, the RISC-V kernel uses the fixmap region to map the
-devicetree. This ensures that the devicetree remains accessible by both virtual
-mappings.
-
-Pre-MMU execution
------------------
-
-A few pieces of code need to run before even the first virtual mapping is
-established. These are the installation of the first virtual mapping itself,
-patching of early alternatives and the early parsing of the kernel command line.
-That code must be very carefully compiled as:
-
-- ``-fno-pie``: This is needed for relocatable kernels which use ``-fPIE``,
-  since otherwise, any access to a global symbol would go through the GOT which
-  is only relocated virtually.
-- ``-mcmodel=medany``: Any access to a global symbol must be PC-relative to
-  avoid any relocations to happen before the MMU is setup.
-- *all* instrumentation must also be disabled (that includes KASAN, ftrace and
-  others).
-
-As using a symbol from a different compilation unit requires this unit to be
-compiled with those flags, we advise, as much as possible, not to use external
-symbols.
diff --git a/Documentation/riscv/features.rst b/Documentation/riscv/features.rst
deleted file mode 100644
index c70ef6ac2368..000000000000
--- a/Documentation/riscv/features.rst
+++ /dev/null
@@ -1,3 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-.. kernel-feat:: $srctree/Documentation/features riscv
diff --git a/Documentation/riscv/hwprobe.rst b/Documentation/riscv/hwprobe.rst
deleted file mode 100644
index a52996b22f75..000000000000
--- a/Documentation/riscv/hwprobe.rst
+++ /dev/null
@@ -1,98 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-RISC-V Hardware Probing Interface
----------------------------------
-
-The RISC-V hardware probing interface is based around a single syscall, which
-is defined in <asm/hwprobe.h>::
-
-    struct riscv_hwprobe {
-        __s64 key;
-        __u64 value;
-    };
-
-    long sys_riscv_hwprobe(struct riscv_hwprobe *pairs, size_t pair_count,
-                           size_t cpu_count, cpu_set_t *cpus,
-                           unsigned int flags);
-
-The arguments are split into three groups: an array of key-value pairs, a CPU
-set, and some flags. The key-value pairs are supplied with a count. Userspace
-must prepopulate the key field for each element, and the kernel will fill in the
-value if the key is recognized. If a key is unknown to the kernel, its key field
-will be cleared to -1, and its value set to 0. The CPU set is defined by
-CPU_SET(3). For value-like keys (eg. vendor/arch/impl), the returned value will
-be only be valid if all CPUs in the given set have the same value. Otherwise -1
-will be returned. For boolean-like keys, the value returned will be a logical
-AND of the values for the specified CPUs. Usermode can supply NULL for cpus and
-0 for cpu_count as a shortcut for all online CPUs. There are currently no flags,
-this value must be zero for future compatibility.
-
-On success 0 is returned, on failure a negative error code is returned.
-
-The following keys are defined:
-
-* :c:macro:`RISCV_HWPROBE_KEY_MVENDORID`: Contains the value of ``mvendorid``,
-  as defined by the RISC-V privileged architecture specification.
-
-* :c:macro:`RISCV_HWPROBE_KEY_MARCHID`: Contains the value of ``marchid``, as
-  defined by the RISC-V privileged architecture specification.
-
-* :c:macro:`RISCV_HWPROBE_KEY_MIMPLID`: Contains the value of ``mimplid``, as
-  defined by the RISC-V privileged architecture specification.
-
-* :c:macro:`RISCV_HWPROBE_KEY_BASE_BEHAVIOR`: A bitmask containing the base
-  user-visible behavior that this kernel supports.  The following base user ABIs
-  are defined:
-
-  * :c:macro:`RISCV_HWPROBE_BASE_BEHAVIOR_IMA`: Support for rv32ima or
-    rv64ima, as defined by version 2.2 of the user ISA and version 1.10 of the
-    privileged ISA, with the following known exceptions (more exceptions may be
-    added, but only if it can be demonstrated that the user ABI is not broken):
-
-    * The ``fence.i`` instruction cannot be directly executed by userspace
-      programs (it may still be executed in userspace via a
-      kernel-controlled mechanism such as the vDSO).
-
-* :c:macro:`RISCV_HWPROBE_KEY_IMA_EXT_0`: A bitmask containing the extensions
-  that are compatible with the :c:macro:`RISCV_HWPROBE_BASE_BEHAVIOR_IMA`:
-  base system behavior.
-
-  * :c:macro:`RISCV_HWPROBE_IMA_FD`: The F and D extensions are supported, as
-    defined by commit cd20cee ("FMIN/FMAX now implement
-    minimumNumber/maximumNumber, not minNum/maxNum") of the RISC-V ISA manual.
-
-  * :c:macro:`RISCV_HWPROBE_IMA_C`: The C extension is supported, as defined
-    by version 2.2 of the RISC-V ISA manual.
-
-  * :c:macro:`RISCV_HWPROBE_IMA_V`: The V extension is supported, as defined by
-    version 1.0 of the RISC-V Vector extension manual.
-
-  * :c:macro:`RISCV_HWPROBE_EXT_ZBA`: The Zba address generation extension is
-       supported, as defined in version 1.0 of the Bit-Manipulation ISA
-       extensions.
-
-  * :c:macro:`RISCV_HWPROBE_EXT_ZBB`: The Zbb extension is supported, as defined
-       in version 1.0 of the Bit-Manipulation ISA extensions.
-
-  * :c:macro:`RISCV_HWPROBE_EXT_ZBS`: The Zbs extension is supported, as defined
-       in version 1.0 of the Bit-Manipulation ISA extensions.
-
-* :c:macro:`RISCV_HWPROBE_KEY_CPUPERF_0`: A bitmask that contains performance
-  information about the selected set of processors.
-
-  * :c:macro:`RISCV_HWPROBE_MISALIGNED_UNKNOWN`: The performance of misaligned
-    accesses is unknown.
-
-  * :c:macro:`RISCV_HWPROBE_MISALIGNED_EMULATED`: Misaligned accesses are
-    emulated via software, either in or below the kernel.  These accesses are
-    always extremely slow.
-
-  * :c:macro:`RISCV_HWPROBE_MISALIGNED_SLOW`: Misaligned accesses are slower
-    than equivalent byte accesses.  Misaligned accesses may be supported
-    directly in hardware, or trapped and emulated by software.
-
-  * :c:macro:`RISCV_HWPROBE_MISALIGNED_FAST`: Misaligned accesses are faster
-    than equivalent byte accesses.
-
-  * :c:macro:`RISCV_HWPROBE_MISALIGNED_UNSUPPORTED`: Misaligned accesses are
-    not supported at all and will generate a misaligned address fault.
diff --git a/Documentation/riscv/index.rst b/Documentation/riscv/index.rst
deleted file mode 100644
index 4dab0cb4b900..000000000000
--- a/Documentation/riscv/index.rst
+++ /dev/null
@@ -1,24 +0,0 @@
-===================
-RISC-V architecture
-===================
-
-.. toctree::
-    :maxdepth: 1
-
-    acpi
-    boot
-    boot-image-header
-    vm-layout
-    hwprobe
-    patch-acceptance
-    uabi
-    vector
-
-    features
-
-.. only::  subproject and html
-
-   Indices
-   =======
-
-   * :ref:`genindex`
diff --git a/Documentation/riscv/patch-acceptance.rst b/Documentation/riscv/patch-acceptance.rst
deleted file mode 100644
index 634aa222b410..000000000000
--- a/Documentation/riscv/patch-acceptance.rst
+++ /dev/null
@@ -1,59 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-arch/riscv maintenance guidelines for developers
-================================================
-
-Overview
---------
-The RISC-V instruction set architecture is developed in the open:
-in-progress drafts are available for all to review and to experiment
-with implementations.  New module or extension drafts can change
-during the development process - sometimes in ways that are
-incompatible with previous drafts.  This flexibility can present a
-challenge for RISC-V Linux maintenance.  Linux maintainers disapprove
-of churn, and the Linux development process prefers well-reviewed and
-tested code over experimental code.  We wish to extend these same
-principles to the RISC-V-related code that will be accepted for
-inclusion in the kernel.
-
-Patchwork
----------
-
-RISC-V has a patchwork instance, where the status of patches can be checked:
-
-  https://patchwork.kernel.org/project/linux-riscv/list/
-
-If your patch does not appear in the default view, the RISC-V maintainers have
-likely either requested changes, or expect it to be applied to another tree.
-
-Automation runs against this patchwork instance, building/testing patches as
-they arrive. The automation applies patches against the current HEAD of the
-RISC-V `for-next` and `fixes` branches, depending on whether the patch has been
-detected as a fix. Failing those, it will use the RISC-V `master` branch.
-The exact commit to which a series has been applied will be noted on patchwork.
-Patches for which any of the checks fail are unlikely to be applied and in most
-cases will need to be resubmitted.
-
-Submit Checklist Addendum
--------------------------
-We'll only accept patches for new modules or extensions if the
-specifications for those modules or extensions are listed as being
-unlikely to be incompatibly changed in the future.  For
-specifications from the RISC-V foundation this means "Frozen" or
-"Ratified", for the UEFI forum specifications this means a published
-ECR.  (Developers may, of course, maintain their own Linux kernel trees
-that contain code for any draft extensions that they wish.)
-
-Additionally, the RISC-V specification allows implementers to create
-their own custom extensions.  These custom extensions aren't required
-to go through any review or ratification process by the RISC-V
-Foundation.  To avoid the maintenance complexity and potential
-performance impact of adding kernel code for implementor-specific
-RISC-V extensions, we'll only consider patches for extensions that either:
-
-- Have been officially frozen or ratified by the RISC-V Foundation, or
-- Have been implemented in hardware that is widely available, per standard
-  Linux practice.
-
-(Implementers, may, of course, maintain their own Linux kernel trees containing
-code for any custom extensions that they wish.)
diff --git a/Documentation/riscv/uabi.rst b/Documentation/riscv/uabi.rst
deleted file mode 100644
index 8960fac42c40..000000000000
--- a/Documentation/riscv/uabi.rst
+++ /dev/null
@@ -1,48 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-RISC-V Linux User ABI
-=====================
-
-ISA string ordering in /proc/cpuinfo
-------------------------------------
-
-The canonical order of ISA extension names in the ISA string is defined in
-chapter 27 of the unprivileged specification.
-The specification uses vague wording, such as should, when it comes to ordering,
-so for our purposes the following rules apply:
-
-#. Single-letter extensions come first, in canonical order.
-   The canonical order is "IMAFDQLCBKJTPVH".
-
-#. All multi-letter extensions will be separated from other extensions by an
-   underscore.
-
-#. Additional standard extensions (starting with 'Z') will be sorted after
-   single-letter extensions and before any higher-privileged extensions.
-
-#. For additional standard extensions, the first letter following the 'Z'
-   conventionally indicates the most closely related alphabetical
-   extension category. If multiple 'Z' extensions are named, they will be
-   ordered first by category, in canonical order, as listed above, then
-   alphabetically within a category.
-
-#. Standard supervisor-level extensions (starting with 'S') will be listed
-   after standard unprivileged extensions.  If multiple supervisor-level
-   extensions are listed, they will be ordered alphabetically.
-
-#. Standard machine-level extensions (starting with 'Zxm') will be listed
-   after any lower-privileged, standard extensions. If multiple machine-level
-   extensions are listed, they will be ordered alphabetically.
-
-#. Non-standard extensions (starting with 'X') will be listed after all standard
-   extensions. If multiple non-standard extensions are listed, they will be
-   ordered alphabetically.
-
-An example string following the order is::
-
-   rv64imadc_zifoo_zigoo_zafoo_sbar_scar_zxmbaz_xqux_xrux
-
-Misaligned accesses
--------------------
-
-Misaligned accesses are supported in userspace, but they may perform poorly.
diff --git a/Documentation/riscv/vector.rst b/Documentation/riscv/vector.rst
deleted file mode 100644
index 75dd88a62e1d..000000000000
--- a/Documentation/riscv/vector.rst
+++ /dev/null
@@ -1,140 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-=========================================
-Vector Extension Support for RISC-V Linux
-=========================================
-
-This document briefly outlines the interface provided to userspace by Linux in
-order to support the use of the RISC-V Vector Extension.
-
-1.  prctl() Interface
----------------------
-
-Two new prctl() calls are added to allow programs to manage the enablement
-status for the use of Vector in userspace. The intended usage guideline for
-these interfaces is to give init systems a way to modify the availability of V
-for processes running under its domain. Calling these interfaces is not
-recommended in libraries routines because libraries should not override policies
-configured from the parant process. Also, users must noted that these interfaces
-are not portable to non-Linux, nor non-RISC-V environments, so it is discourage
-to use in a portable code. To get the availability of V in an ELF program,
-please read :c:macro:`COMPAT_HWCAP_ISA_V` bit of :c:macro:`ELF_HWCAP` in the
-auxiliary vector.
-
-* prctl(PR_RISCV_V_SET_CONTROL, unsigned long arg)
-
-    Sets the Vector enablement status of the calling thread, where the control
-    argument consists of two 2-bit enablement statuses and a bit for inheritance
-    mode. Other threads of the calling process are unaffected.
-
-    Enablement status is a tri-state value each occupying 2-bit of space in
-    the control argument:
-
-    * :c:macro:`PR_RISCV_V_VSTATE_CTRL_DEFAULT`: Use the system-wide default
-      enablement status on execve(). The system-wide default setting can be
-      controlled via sysctl interface (see sysctl section below).
-
-    * :c:macro:`PR_RISCV_V_VSTATE_CTRL_ON`: Allow Vector to be run for the
-      thread.
-
-    * :c:macro:`PR_RISCV_V_VSTATE_CTRL_OFF`: Disallow Vector. Executing Vector
-      instructions under such condition will trap and casuse the termination of the thread.
-
-    arg: The control argument is a 5-bit value consisting of 3 parts, and
-    accessed by 3 masks respectively.
-
-    The 3 masks, PR_RISCV_V_VSTATE_CTRL_CUR_MASK,
-    PR_RISCV_V_VSTATE_CTRL_NEXT_MASK, and PR_RISCV_V_VSTATE_CTRL_INHERIT
-    represents bit[1:0], bit[3:2], and bit[4]. bit[1:0] accounts for the
-    enablement status of current thread, and the setting at bit[3:2] takes place
-    at next execve(). bit[4] defines the inheritance mode of the setting in
-    bit[3:2].
-
-        * :c:macro:`PR_RISCV_V_VSTATE_CTRL_CUR_MASK`: bit[1:0]: Account for the
-          Vector enablement status for the calling thread. The calling thread is
-          not able to turn off Vector once it has been enabled. The prctl() call
-          fails with EPERM if the value in this mask is PR_RISCV_V_VSTATE_CTRL_OFF
-          but the current enablement status is not off. Setting
-          PR_RISCV_V_VSTATE_CTRL_DEFAULT here takes no effect but to set back
-          the original enablement status.
-
-        * :c:macro:`PR_RISCV_V_VSTATE_CTRL_NEXT_MASK`: bit[3:2]: Account for the
-          Vector enablement setting for the calling thread at the next execve()
-          system call. If PR_RISCV_V_VSTATE_CTRL_DEFAULT is used in this mask,
-          then the enablement status will be decided by the system-wide
-          enablement status when execve() happen.
-
-        * :c:macro:`PR_RISCV_V_VSTATE_CTRL_INHERIT`: bit[4]: the inheritance
-          mode for the setting at PR_RISCV_V_VSTATE_CTRL_NEXT_MASK. If the bit
-          is set then the following execve() will not clear the setting in both
-          PR_RISCV_V_VSTATE_CTRL_NEXT_MASK and PR_RISCV_V_VSTATE_CTRL_INHERIT.
-          This setting persists across changes in the system-wide default value.
-
-    Return value:
-        * 0 on success;
-        * EINVAL: Vector not supported, invalid enablement status for current or
-          next mask;
-        * EPERM: Turning off Vector in PR_RISCV_V_VSTATE_CTRL_CUR_MASK if Vector
-          was enabled for the calling thread.
-
-    On success:
-        * A valid setting for PR_RISCV_V_VSTATE_CTRL_CUR_MASK takes place
-          immediately. The enablement status specified in
-          PR_RISCV_V_VSTATE_CTRL_NEXT_MASK happens at the next execve() call, or
-          all following execve() calls if PR_RISCV_V_VSTATE_CTRL_INHERIT bit is
-          set.
-        * Every successful call overwrites a previous setting for the calling
-          thread.
-
-* prctl(PR_RISCV_V_GET_CONTROL)
-
-    Gets the same Vector enablement status for the calling thread. Setting for
-    next execve() call and the inheritance bit are all OR-ed together.
-
-    Note that ELF programs are able to get the availability of V for itself by
-    reading :c:macro:`COMPAT_HWCAP_ISA_V` bit of :c:macro:`ELF_HWCAP` in the
-    auxiliary vector.
-
-    Return value:
-        * a nonnegative value on success;
-        * EINVAL: Vector not supported.
-
-2.  System runtime configuration (sysctl)
------------------------------------------
-
-To mitigate the ABI impact of expansion of the signal stack, a
-policy mechanism is provided to the administrators, distro maintainers, and
-developers to control the default Vector enablement status for userspace
-processes in form of sysctl knob:
-
-* /proc/sys/abi/riscv_v_default_allow
-
-    Writing the text representation of 0 or 1 to this file sets the default
-    system enablement status for new starting userspace programs. Valid values
-    are:
-
-    * 0: Do not allow Vector code to be executed as the default for new processes.
-    * 1: Allow Vector code to be executed as the default for new processes.
-
-    Reading this file returns the current system default enablement status.
-
-    At every execve() call, a new enablement status of the new process is set to
-    the system default, unless:
-
-      * PR_RISCV_V_VSTATE_CTRL_INHERIT is set for the calling process, and the
-        setting in PR_RISCV_V_VSTATE_CTRL_NEXT_MASK is not
-        PR_RISCV_V_VSTATE_CTRL_DEFAULT. Or,
-
-      * The setting in PR_RISCV_V_VSTATE_CTRL_NEXT_MASK is not
-        PR_RISCV_V_VSTATE_CTRL_DEFAULT.
-
-    Modifying the system default enablement status does not affect the enablement
-    status of any existing process of thread that do not make an execve() call.
-
-3.  Vector Register State Across System Calls
----------------------------------------------
-
-As indicated by version 1.0 of the V extension [1], vector registers are
-clobbered by system calls.
-
-1: https://github.com/riscv/riscv-v-spec/blob/master/calling-convention.adoc
diff --git a/Documentation/riscv/vm-layout.rst b/Documentation/riscv/vm-layout.rst
deleted file mode 100644
index 69ff6da1dbf8..000000000000
--- a/Documentation/riscv/vm-layout.rst
+++ /dev/null
@@ -1,157 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-=====================================
-Virtual Memory Layout on RISC-V Linux
-=====================================
-
-:Author: Alexandre Ghiti <alex@ghiti.fr>
-:Date: 12 February 2021
-
-This document describes the virtual memory layout used by the RISC-V Linux
-Kernel.
-
-RISC-V Linux Kernel 32bit
-=========================
-
-RISC-V Linux Kernel SV32
-------------------------
-
-TODO
-
-RISC-V Linux Kernel 64bit
-=========================
-
-The RISC-V privileged architecture document states that the 64bit addresses
-"must have bits 63–48 all equal to bit 47, or else a page-fault exception will
-occur.": that splits the virtual address space into 2 halves separated by a very
-big hole, the lower half is where the userspace resides, the upper half is where
-the RISC-V Linux Kernel resides.
-
-RISC-V Linux Kernel SV39
-------------------------
-
-::
-
-  ========================================================================================================================
-      Start addr    |   Offset   |     End addr     |  Size   | VM area description
-  ========================================================================================================================
-                    |            |                  |         |
-   0000000000000000 |    0       | 0000003fffffffff |  256 GB | user-space virtual memory, different per mm
-  __________________|____________|__________________|_________|___________________________________________________________
-                    |            |                  |         |
-   0000004000000000 | +256    GB | ffffffbfffffffff | ~16M TB | ... huge, almost 64 bits wide hole of non-canonical
-                    |            |                  |         |     virtual memory addresses up to the -256 GB
-                    |            |                  |         |     starting offset of kernel mappings.
-  __________________|____________|__________________|_________|___________________________________________________________
-                                                              |
-                                                              | Kernel-space virtual memory, shared between all processes:
-  ____________________________________________________________|___________________________________________________________
-                    |            |                  |         |
-   ffffffc6fea00000 | -228    GB | ffffffc6feffffff |    6 MB | fixmap
-   ffffffc6ff000000 | -228    GB | ffffffc6ffffffff |   16 MB | PCI io
-   ffffffc700000000 | -228    GB | ffffffc7ffffffff |    4 GB | vmemmap
-   ffffffc800000000 | -224    GB | ffffffd7ffffffff |   64 GB | vmalloc/ioremap space
-   ffffffd800000000 | -160    GB | fffffff6ffffffff |  124 GB | direct mapping of all physical memory
-   fffffff700000000 |  -36    GB | fffffffeffffffff |   32 GB | kasan
-  __________________|____________|__________________|_________|____________________________________________________________
-                                                              |
-                                                              |
-  ____________________________________________________________|____________________________________________________________
-                    |            |                  |         |
-   ffffffff00000000 |   -4    GB | ffffffff7fffffff |    2 GB | modules, BPF
-   ffffffff80000000 |   -2    GB | ffffffffffffffff |    2 GB | kernel
-  __________________|____________|__________________|_________|____________________________________________________________
-
-
-RISC-V Linux Kernel SV48
-------------------------
-
-::
-
- ========================================================================================================================
-      Start addr    |   Offset   |     End addr     |  Size   | VM area description
- ========================================================================================================================
-                    |            |                  |         |
-   0000000000000000 |    0       | 00007fffffffffff |  128 TB | user-space virtual memory, different per mm
-  __________________|____________|__________________|_________|___________________________________________________________
-                    |            |                  |         |
-   0000800000000000 | +128    TB | ffff7fffffffffff | ~16M TB | ... huge, almost 64 bits wide hole of non-canonical
-                    |            |                  |         | virtual memory addresses up to the -128 TB
-                    |            |                  |         | starting offset of kernel mappings.
-  __________________|____________|__________________|_________|___________________________________________________________
-                                                              |
-                                                              | Kernel-space virtual memory, shared between all processes:
-  ____________________________________________________________|___________________________________________________________
-                    |            |                  |         |
-   ffff8d7ffea00000 |  -114.5 TB | ffff8d7ffeffffff |    6 MB | fixmap
-   ffff8d7fff000000 |  -114.5 TB | ffff8d7fffffffff |   16 MB | PCI io
-   ffff8d8000000000 |  -114.5 TB | ffff8f7fffffffff |    2 TB | vmemmap
-   ffff8f8000000000 |  -112.5 TB | ffffaf7fffffffff |   32 TB | vmalloc/ioremap space
-   ffffaf8000000000 |  -80.5  TB | ffffef7fffffffff |   64 TB | direct mapping of all physical memory
-   ffffef8000000000 |  -16.5  TB | fffffffeffffffff | 16.5 TB | kasan
-  __________________|____________|__________________|_________|____________________________________________________________
-                                                              |
-                                                              | Identical layout to the 39-bit one from here on:
-  ____________________________________________________________|____________________________________________________________
-                    |            |                  |         |
-   ffffffff00000000 |   -4    GB | ffffffff7fffffff |    2 GB | modules, BPF
-   ffffffff80000000 |   -2    GB | ffffffffffffffff |    2 GB | kernel
-  __________________|____________|__________________|_________|____________________________________________________________
-
-
-RISC-V Linux Kernel SV57
-------------------------
-
-::
-
- ========================================================================================================================
-      Start addr    |   Offset   |     End addr     |  Size   | VM area description
- ========================================================================================================================
-                    |            |                  |         |
-   0000000000000000 |   0        | 00ffffffffffffff |   64 PB | user-space virtual memory, different per mm
-  __________________|____________|__________________|_________|___________________________________________________________
-                    |            |                  |         |
-   0100000000000000 | +64     PB | feffffffffffffff | ~16K PB | ... huge, almost 64 bits wide hole of non-canonical
-                    |            |                  |         | virtual memory addresses up to the -64 PB
-                    |            |                  |         | starting offset of kernel mappings.
-  __________________|____________|__________________|_________|___________________________________________________________
-                                                              |
-                                                              | Kernel-space virtual memory, shared between all processes:
-  ____________________________________________________________|___________________________________________________________
-                    |            |                  |         |
-   ff1bfffffea00000 | -57     PB | ff1bfffffeffffff |    6 MB | fixmap
-   ff1bffffff000000 | -57     PB | ff1bffffffffffff |   16 MB | PCI io
-   ff1c000000000000 | -57     PB | ff1fffffffffffff |    1 PB | vmemmap
-   ff20000000000000 | -56     PB | ff5fffffffffffff |   16 PB | vmalloc/ioremap space
-   ff60000000000000 | -40     PB | ffdeffffffffffff |   32 PB | direct mapping of all physical memory
-   ffdf000000000000 |  -8     PB | fffffffeffffffff |    8 PB | kasan
-  __________________|____________|__________________|_________|____________________________________________________________
-                                                              |
-                                                              | Identical layout to the 39-bit one from here on:
-  ____________________________________________________________|____________________________________________________________
-                    |            |                  |         |
-   ffffffff00000000 |  -4     GB | ffffffff7fffffff |    2 GB | modules, BPF
-   ffffffff80000000 |  -2     GB | ffffffffffffffff |    2 GB | kernel
-  __________________|____________|__________________|_________|____________________________________________________________
-
-
-Userspace VAs
---------------------
-To maintain compatibility with software that relies on the VA space with a
-maximum of 48 bits the kernel will, by default, return virtual addresses to
-userspace from a 48-bit range (sv48). This default behavior is achieved by
-passing 0 into the hint address parameter of mmap. On CPUs with an address space
-smaller than sv48, the CPU maximum supported address space will be the default.
-
-Software can "opt-in" to receiving VAs from another VA space by providing
-a hint address to mmap. A hint address passed to mmap will cause the largest
-address space that fits entirely into the hint to be used, unless there is no
-space left in the address space. If there is no space available in the requested
-address space, an address in the next smallest available address space will be
-returned.
-
-For example, in order to obtain 48-bit VA space, a hint address greater than
-:code:`1 << 47` must be provided. Note that this is 47 due to sv48 userspace
-ending at :code:`1 << 47` and the addresses beyond this are reserved for the
-kernel. Similarly, to obtain 57-bit VA space addresses, a hint address greater
-than or equal to :code:`1 << 56` must be provided.