docs: move superh documentation under Documentation/arch/

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.  Move
Documentation/sh into arch/ and fix all in-tree references.

Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

5 files changed, 0 insertions, 388 deletions

diff --git a/Documentation/sh/booting.rst b/Documentation/sh/booting.rst
deleted file mode 100644
index d851c49a01bf..000000000000
--- a/Documentation/sh/booting.rst
+++ /dev/null
@@ -1,12 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-DeviceTree Booting
-------------------
-
-  Device-tree compatible SH bootloaders are expected to provide the physical
-  address of the device tree blob in r4. Since legacy bootloaders did not
-  guarantee any particular initial register state, kernels built to
-  inter-operate with old bootloaders must either use a builtin DTB or
-  select a legacy board option (something other than CONFIG_SH_DEVICE_TREE)
-  that does not use device tree. Support for the latter is being phased out
-  in favor of device tree.
diff --git a/Documentation/sh/features.rst b/Documentation/sh/features.rst
deleted file mode 100644
index f722af3b6c99..000000000000
--- a/Documentation/sh/features.rst
+++ /dev/null
@@ -1,3 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-.. kernel-feat:: $srctree/Documentation/features sh
diff --git a/Documentation/sh/index.rst b/Documentation/sh/index.rst
deleted file mode 100644
index c64776738cf6..000000000000
--- a/Documentation/sh/index.rst
+++ /dev/null
@@ -1,56 +0,0 @@
-=======================
-SuperH Interfaces Guide
-=======================
-
-:Author: Paul Mundt
-
-.. toctree::
-    :maxdepth: 1
-
-    booting
-    new-machine
-    register-banks
-
-    features
-
-Memory Management
-=================
-
-SH-4
-----
-
-Store Queue API
-~~~~~~~~~~~~~~~
-
-.. kernel-doc:: arch/sh/kernel/cpu/sh4/sq.c
-   :export:
-
-Machine Specific Interfaces
-===========================
-
-mach-dreamcast
---------------
-
-.. kernel-doc:: arch/sh/boards/mach-dreamcast/rtc.c
-   :internal:
-
-mach-x3proto
-------------
-
-.. kernel-doc:: arch/sh/boards/mach-x3proto/ilsel.c
-   :export:
-
-Busses
-======
-
-SuperHyway
-----------
-
-.. kernel-doc:: drivers/sh/superhyway/superhyway.c
-   :export:
-
-Maple
------
-
-.. kernel-doc:: drivers/sh/maple/maple.c
-   :export:
diff --git a/Documentation/sh/new-machine.rst b/Documentation/sh/new-machine.rst
deleted file mode 100644
index e501c52b3b30..000000000000
--- a/Documentation/sh/new-machine.rst
+++ /dev/null
@@ -1,277 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-=============================
-Adding a new board to LinuxSH
-=============================
-
-               Paul Mundt <lethal@linux-sh.org>
-
-This document attempts to outline what steps are necessary to add support
-for new boards to the LinuxSH port under the new 2.5 and 2.6 kernels. This
-also attempts to outline some of the noticeable changes between the 2.4
-and the 2.5/2.6 SH backend.
-
-1. New Directory Structure
-==========================
-
-The first thing to note is the new directory structure. Under 2.4, most
-of the board-specific code (with the exception of stboards) ended up
-in arch/sh/kernel/ directly, with board-specific headers ending up in
-include/asm-sh/. For the new kernel, things are broken out by board type,
-companion chip type, and CPU type. Looking at a tree view of this directory
-hierarchy looks like the following:
-
-Board-specific code::
-
-    .
-    |-- arch
-    |   `-- sh
-    |       `-- boards
-    |           |-- adx
-    |           |   `-- board-specific files
-    |           |-- bigsur
-    |           |   `-- board-specific files
-    |           |
-    |           ... more boards here ...
-    |
-    `-- include
-	`-- asm-sh
-	    |-- adx
-	    |   `-- board-specific headers
-	    |-- bigsur
-	    |   `-- board-specific headers
-	    |
-	    .. more boards here ...
-
-Next, for companion chips::
-
-    .
-    `-- arch
-	`-- sh
-	    `-- cchips
-		`-- hd6446x
-		    `-- hd64461
-			`-- cchip-specific files
-
-... and so on. Headers for the companion chips are treated the same way as
-board-specific headers. Thus, include/asm-sh/hd64461 is home to all of the
-hd64461-specific headers.
-
-Finally, CPU family support is also abstracted::
-
-    .
-    |-- arch
-    |   `-- sh
-    |       |-- kernel
-    |       |   `-- cpu
-    |       |       |-- sh2
-    |       |       |   `-- SH-2 generic files
-    |       |       |-- sh3
-    |       |       |   `-- SH-3 generic files
-    |       |       `-- sh4
-    |       |           `-- SH-4 generic files
-    |       `-- mm
-    |           `-- This is also broken out per CPU family, so each family can
-    |               have their own set of cache/tlb functions.
-    |
-    `-- include
-	`-- asm-sh
-	    |-- cpu-sh2
-	    |   `-- SH-2 specific headers
-	    |-- cpu-sh3
-	    |   `-- SH-3 specific headers
-	    `-- cpu-sh4
-		`-- SH-4 specific headers
-
-It should be noted that CPU subtypes are _not_ abstracted. Thus, these still
-need to be dealt with by the CPU family specific code.
-
-2. Adding a New Board
-=====================
-
-The first thing to determine is whether the board you are adding will be
-isolated, or whether it will be part of a family of boards that can mostly
-share the same board-specific code with minor differences.
-
-In the first case, this is just a matter of making a directory for your
-board in arch/sh/boards/ and adding rules to hook your board in with the
-build system (more on this in the next section). However, for board families
-it makes more sense to have a common top-level arch/sh/boards/ directory
-and then populate that with sub-directories for each member of the family.
-Both the Solution Engine and the hp6xx boards are an example of this.
-
-After you have setup your new arch/sh/boards/ directory, remember that you
-should also add a directory in include/asm-sh for headers localized to this
-board (if there are going to be more than one). In order to interoperate
-seamlessly with the build system, it's best to have this directory the same
-as the arch/sh/boards/ directory name, though if your board is again part of
-a family, the build system has ways of dealing with this (via incdir-y
-overloading), and you can feel free to name the directory after the family
-member itself.
-
-There are a few things that each board is required to have, both in the
-arch/sh/boards and the include/asm-sh/ hierarchy. In order to better
-explain this, we use some examples for adding an imaginary board. For
-setup code, we're required at the very least to provide definitions for
-get_system_type() and platform_setup(). For our imaginary board, this
-might look something like::
-
-    /*
-    * arch/sh/boards/vapor/setup.c - Setup code for imaginary board
-    */
-    #include <linux/init.h>
-
-    const char *get_system_type(void)
-    {
-	    return "FooTech Vaporboard";
-    }
-
-    int __init platform_setup(void)
-    {
-	    /*
-	    * If our hardware actually existed, we would do real
-	    * setup here. Though it's also sane to leave this empty
-	    * if there's no real init work that has to be done for
-	    * this board.
-	    */
-
-	    /* Start-up imaginary PCI ... */
-
-	    /* And whatever else ... */
-
-	    return 0;
-    }
-
-Our new imaginary board will also have to tie into the machvec in order for it
-to be of any use.
-
-machvec functions fall into a number of categories:
-
- - I/O functions to IO memory (inb etc) and PCI/main memory (readb etc).
- - I/O mapping functions (ioport_map, ioport_unmap, etc).
- - a 'heartbeat' function.
- - PCI and IRQ initialization routines.
- - Consistent allocators (for boards that need special allocators,
-   particularly for allocating out of some board-specific SRAM for DMA
-   handles).
-
-There are machvec functions added and removed over time, so always be sure to
-consult include/asm-sh/machvec.h for the current state of the machvec.
-
-The kernel will automatically wrap in generic routines for undefined function
-pointers in the machvec at boot time, as machvec functions are referenced
-unconditionally throughout most of the tree. Some boards have incredibly
-sparse machvecs (such as the dreamcast and sh03), whereas others must define
-virtually everything (rts7751r2d).
-
-Adding a new machine is relatively trivial (using vapor as an example):
-
-If the board-specific definitions are quite minimalistic, as is the case for
-the vast majority of boards, simply having a single board-specific header is
-sufficient.
-
- - add a new file include/asm-sh/vapor.h which contains prototypes for
-   any machine specific IO functions prefixed with the machine name, for
-   example vapor_inb. These will be needed when filling out the machine
-   vector.
-
-   Note that these prototypes are generated automatically by setting
-   __IO_PREFIX to something sensible. A typical example would be::
-
-	#define __IO_PREFIX vapor
-	#include <asm/io_generic.h>
-
-   somewhere in the board-specific header. Any boards being ported that still
-   have a legacy io.h should remove it entirely and switch to the new model.
-
- - Add machine vector definitions to the board's setup.c. At a bare minimum,
-   this must be defined as something like::
-
-	struct sh_machine_vector mv_vapor __initmv = {
-		.mv_name = "vapor",
-	};
-	ALIAS_MV(vapor)
-
- - finally add a file arch/sh/boards/vapor/io.c, which contains definitions of
-   the machine specific io functions (if there are enough to warrant it).
-
-3. Hooking into the Build System
-================================
-
-Now that we have the corresponding directories setup, and all of the
-board-specific code is in place, it's time to look at how to get the
-whole mess to fit into the build system.
-
-Large portions of the build system are now entirely dynamic, and merely
-require the proper entry here and there in order to get things done.
-
-The first thing to do is to add an entry to arch/sh/Kconfig, under the
-"System type" menu::
-
-    config SH_VAPOR
-	    bool "Vapor"
-	    help
-	    select Vapor if configuring for a FooTech Vaporboard.
-
-next, this has to be added into arch/sh/Makefile. All boards require a
-machdir-y entry in order to be built. This entry needs to be the name of
-the board directory as it appears in arch/sh/boards, even if it is in a
-sub-directory (in which case, all parent directories below arch/sh/boards/
-need to be listed). For our new board, this entry can look like::
-
-    machdir-$(CONFIG_SH_VAPOR)	+= vapor
-
-provided that we've placed everything in the arch/sh/boards/vapor/ directory.
-
-Next, the build system assumes that your include/asm-sh directory will also
-be named the same. If this is not the case (as is the case with multiple
-boards belonging to a common family), then the directory name needs to be
-implicitly appended to incdir-y. The existing code manages this for the
-Solution Engine and hp6xx boards, so see these for an example.
-
-Once that is taken care of, it's time to add an entry for the mach type.
-This is done by adding an entry to the end of the arch/sh/tools/mach-types
-list. The method for doing this is self explanatory, and so we won't waste
-space restating it here. After this is done, you will be able to use
-implicit checks for your board if you need this somewhere throughout the
-common code, such as::
-
-	/* Make sure we're on the FooTech Vaporboard */
-	if (!mach_is_vapor())
-		return -ENODEV;
-
-also note that the mach_is_boardname() check will be implicitly forced to
-lowercase, regardless of the fact that the mach-types entries are all
-uppercase. You can read the script if you really care, but it's pretty ugly,
-so you probably don't want to do that.
-
-Now all that's left to do is providing a defconfig for your new board. This
-way, other people who end up with this board can simply use this config
-for reference instead of trying to guess what settings are supposed to be
-used on it.
-
-Also, as soon as you have copied over a sample .config for your new board
-(assume arch/sh/configs/vapor_defconfig), you can also use this directly as a
-build target, and it will be implicitly listed as such in the help text.
-
-Looking at the 'make help' output, you should now see something like:
-
-Architecture specific targets (sh):
-
-  =======================   =============================================
-  zImage                    Compressed kernel image (arch/sh/boot/zImage)
-  adx_defconfig             Build for adx
-  cqreek_defconfig          Build for cqreek
-  dreamcast_defconfig       Build for dreamcast
-  ...
-  vapor_defconfig           Build for vapor
-  =======================   =============================================
-
-which then allows you to do::
-
-    $ make ARCH=sh CROSS_COMPILE=sh4-linux- vapor_defconfig vmlinux
-
-which will in turn copy the defconfig for this board, run it through
-oldconfig (prompting you for any new options since the time of creation),
-and start you on your way to having a functional kernel for your new
-board.
diff --git a/Documentation/sh/register-banks.rst b/Documentation/sh/register-banks.rst
deleted file mode 100644
index 2bef5c8fcbbc..000000000000
--- a/Documentation/sh/register-banks.rst
+++ /dev/null
@@ -1,40 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-==========================================
-Notes on register bank usage in the kernel
-==========================================
-
-Introduction
-------------
-
-The SH-3 and SH-4 CPU families traditionally include a single partial register
-bank (selected by SR.RB, only r0 ... r7 are banked), whereas other families
-may have more full-featured banking or simply no such capabilities at all.
-
-SR.RB banking
--------------
-
-In the case of this type of banking, banked registers are mapped directly to
-r0 ... r7 if SR.RB is set to the bank we are interested in, otherwise ldc/stc
-can still be used to reference the banked registers (as r0_bank ... r7_bank)
-when in the context of another bank. The developer must keep the SR.RB value
-in mind when writing code that utilizes these banked registers, for obvious
-reasons. Userspace is also not able to poke at the bank1 values, so these can
-be used rather effectively as scratch registers by the kernel.
-
-Presently the kernel uses several of these registers.
-
-	- r0_bank, r1_bank (referenced as k0 and k1, used for scratch
-	  registers when doing exception handling).
-
-	- r2_bank (used to track the EXPEVT/INTEVT code)
-
-		- Used by do_IRQ() and friends for doing irq mapping based off
-		  of the interrupt exception vector jump table offset
-
-	- r6_bank (global interrupt mask)
-
-		- The SR.IMASK interrupt handler makes use of this to set the
-		  interrupt priority level (used by local_irq_enable())
-
-	- r7_bank (current)