docs: xtensa: convert to ReST

Rename the xtensa documentation files to ReST, add an
index for them and adjust in order to produce a nice html
output via the Sphinx build system.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

1 files changed, 0 insertions, 44 deletions

diff --git a/Documentation/xtensa/atomctl.txt b/Documentation/xtensa/atomctl.txt
deleted file mode 100644
index 1da783ac200c..000000000000
--- a/Documentation/xtensa/atomctl.txt
+++ /dev/null
@@ -1,44 +0,0 @@
-We Have Atomic Operation Control (ATOMCTL) Register.
-This register determines the effect of using a S32C1I instruction
-with various combinations of:
-
-     1. With and without an Coherent Cache Controller which
-        can do Atomic Transactions to the memory internally.
-
-     2. With and without An Intelligent Memory Controller which
-        can do Atomic Transactions itself.
-
-The Core comes up with a default value of for the three types of cache ops:
-
-      0x28: (WB: Internal, WT: Internal, BY:Exception)
-
-On the FPGA Cards we typically simulate an Intelligent Memory controller
-which can implement  RCW transactions. For FPGA cards with an External
-Memory controller we let it to the atomic operations internally while
-doing a Cached (WB) transaction and use the Memory RCW for un-cached
-operations.
-
-For systems without an coherent cache controller, non-MX, we always
-use the memory controllers RCW, thought non-MX controlers likely
-support the Internal Operation.
-
-CUSTOMER-WARNING:
-   Virtually all customers buy their memory controllers from vendors that
-   don't support atomic RCW memory transactions and will likely want to
-   configure this register to not use RCW.
-
-Developers might find using RCW in Bypass mode convenient when testing
-with the cache being bypassed; for example studying cache alias problems.
-
-See Section 4.3.12.4 of ISA; Bits:
-
-                             WB     WT      BY
-                           5   4 | 3   2 | 1   0
-  2 Bit
-  Field
-  Values     WB - Write Back         WT - Write Thru         BY - Bypass
----------    ---------------         -----------------     ----------------
-    0        Exception               Exception               Exception
-    1        RCW Transaction         RCW Transaction         RCW Transaction
-    2        Internal Operation      Internal Operation      Reserved
-    3        Reserved                Reserved                Reserved