docs: move s390 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 <[e-mail]>
Reviewed-by: Tony Krowiak <[e-mail]>
Acked-by: Jonathan Corbet <[e-mail]>
Acked-by: Heiko Carstens <[e-mail]>
Reviewed-by: Philippe Mathieu-Daudé <[e-mail]>
Reviewed-by: Randy Dunlap <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Heiko Carstens <[e-mail]>

Documentation/admin-guide/kernel-parameters.txt

···
 			others).
 
 	ccw_timeout_log	[S390]
-			See Documentation/s390/common_io.rst for details.
+			See Documentation/arch/s390/common_io.rst for details.
 
 	cgroup_disable=	[KNL] Disable a particular controller or optional feature
 			Format: {name of the controller(s) or feature(s) to disable}
···
 			Setting checkreqprot to 1 is deprecated.
 
 	cio_ignore=	[S390]
-			See Documentation/s390/common_io.rst for details.
+			See Documentation/arch/s390/common_io.rst for details.
 
 	clearcpuid=X[,X...] [X86]
 			Disable CPUID feature X for the kernel. See

Documentation/arch/index.rst

···
    parisc/index
    ../powerpc/index
    ../riscv/index
-   ../s390/index
+   s390/index
    sh/index
    sparc/index
    x86/index

Documentation/driver-api/s390-drivers.rst

···
 although they are not the focus of this document.
 
 Some additional information can also be found in the kernel source under
-Documentation/s390/driver-model.rst.
+Documentation/arch/s390/driver-model.rst.
 
 The css bus
 ===========
···
 * Standard I/O subchannels, for use by the system. They have a child
   device on the ccw bus and are described below.
 * I/O subchannels bound to the vfio-ccw driver. See
-  Documentation/s390/vfio-ccw.rst.
+  Documentation/arch/s390/vfio-ccw.rst.
 * Message subchannels. No Linux driver currently exists.
 * CHSC subchannels (at most one). The chsc subchannel driver can be used
   to send asynchronous chsc commands.

Documentation/s390/3270.rst Documentation/arch/s390/3270.rst

···
 	as a 3270, not a 3215.
 
 	5. Run the 3270 configuration script config3270.  It is
-	distributed in this same directory, Documentation/s390, as
+	distributed in this same directory, Documentation/arch/s390, as
 	config3270.sh.  Inspect the output script it produces,
 	/tmp/mkdev3270, and then run that script.  This will create the
 	necessary character special device files and make the necessary
···
 	Then notify /sbin/init that /etc/inittab has changed, by issuing
 	the telinit command with the q operand::
 
-		cd Documentation/s390
+		cd Documentation/arch/s390
 		sh config3270.sh
 		sh /tmp/mkdev3270
 		telinit q

Documentation/s390/cds.rst Documentation/arch/s390/cds.rst

···
 
 Note:
   In order to write a driver for S/390, you also need to look into the interface
-  described in Documentation/s390/driver-model.rst.
+  described in Documentation/arch/s390/driver-model.rst.
 
 Note for porting drivers from 2.4:
 

Documentation/s390/common_io.rst Documentation/arch/s390/common_io.rst

···
 
   The level of logging can be changed to be more or less verbose by piping to
   /sys/kernel/debug/s390dbf/cio_*/level a number between 0 and 6; see the
-  documentation on the S/390 debug feature (Documentation/s390/s390dbf.rst)
+  documentation on the S/390 debug feature (Documentation/arch/s390/s390dbf.rst)
   for details.

Documentation/s390/pci.rst Documentation/arch/s390/pci.rst

···
   Change the level of logging to be more or less verbose by piping
   a number between 0 and 6 to  /sys/kernel/debug/s390dbf/pci_*/level. For
   details, see the documentation on the S/390 debug feature at
-  Documentation/s390/s390dbf.rst.
+  Documentation/arch/s390/s390dbf.rst.
 
 Sysfs entries
 =============

Documentation/s390/vfio-ccw.rst Documentation/arch/s390/vfio-ccw.rst

···
 1. ESA/s390 Principles of Operation manual (IBM Form. No. SA22-7832)
 2. ESA/390 Common I/O Device Commands manual (IBM Form. No. SA22-7204)
 3. https://en.wikipedia.org/wiki/Channel_I/O
-4. Documentation/s390/cds.rst
+4. Documentation/arch/s390/cds.rst
 5. Documentation/driver-api/vfio.rst
 6. Documentation/driver-api/vfio-mediated-device.rst

MAINTAINERS

···
 S:	Supported
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git
 F:	Documentation/driver-api/s390-drivers.rst
-F:	Documentation/s390/
+F:	Documentation/arch/s390/
 F:	arch/s390/
 F:	drivers/s390/
 F:	drivers/watchdog/diag288_wdt.c
···
 M:	Gerald Schaefer <[e-mail]>
 L:	[e-mail]
 S:	Supported
-F:	Documentation/s390/pci.rst
+F:	Documentation/arch/s390/pci.rst
 F:	arch/s390/pci/
 F:	drivers/pci/hotplug/s390_pci_hpc.c
 
···
 M:	Jason Herne <[e-mail]>
 L:	[e-mail]
 S:	Supported
-F:	Documentation/s390/vfio-ap*
+F:	Documentation/arch/s390/vfio-ap*
 F:	drivers/s390/crypto/vfio_ap*
 
 S390 VFIO-CCW DRIVER
···
 L:	[e-mail]
 L:	[e-mail]
 S:	Supported
-F:	Documentation/s390/vfio-ccw.rst
+F:	Documentation/arch/s390/vfio-ccw.rst
 F:	drivers/s390/cio/vfio_ccw*
 F:	include/uapi/linux/vfio_ccw.h
 

arch/s390/Kconfig

···
 	  Crash dump kernels are loaded in the main kernel with kexec-tools
 	  into a specially reserved region and then later executed after
 	  a crash by kdump/kexec.
-	  Refer to <file:Documentation/s390/zfcpdump.rst> for more details on this.
+	  Refer to <file:Documentation/arch/s390/zfcpdump.rst> for more details on this.
 	  This option also enables s390 zfcpdump.
-	  See also <file:Documentation/s390/zfcpdump.rst>
+	  See also <file:Documentation/arch/s390/zfcpdump.rst>
 
 endmenu
 

arch/s390/include/asm/debug.h

···
 
 /*
  * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are
- * stored in the s390dbf. See Documentation/s390/s390dbf.rst for more details!
+ * stored in the s390dbf. See Documentation/arch/s390/s390dbf.rst for more details!
  */
 extern debug_entry_t *
 __debug_sprintf_event(debug_info_t *id, int level, char *string, ...)
···
 
 /*
  * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are
- * stored in the s390dbf. See Documentation/s390/s390dbf.rst for more details!
+ * stored in the s390dbf. See Documentation/arch/s390/s390dbf.rst for more details!
  */
 extern debug_entry_t *
 __debug_sprintf_exception(debug_info_t *id, int level, char *string, ...)

drivers/s390/char/zcore.c

···
  * zcore module to export memory content and register sets for creating system
  * dumps on SCSI/NVMe disks (zfcp/nvme dump).
  *
- * For more information please refer to Documentation/s390/zfcpdump.rst
+ * For more information please refer to Documentation/arch/s390/zfcpdump.rst
  *
  * Copyright IBM Corp. 2003, 2008
  * Author(s): Michael Holzheu