nds32: Remove the architecture

The nds32 architecture, also known as AndeStar V3, is a custom 32-bit
RISC target designed by Andes Technologies. Support was added to the
kernel in 2016 as the replacement RISC-V based V5 processors were
already announced, and maintained by (current or former) Andes
employees.

As explained by Alan Kao, new customers are now all using RISC-V,
and all known nds32 users are already on longterm stable kernels
provided by Andes, with no development work going into mainline
support any more.

While the port is still in a reasonably good shape, it only gets
worse over time without active maintainers, so it seems best
to remove it before it becomes unusable. As always, if it turns
out that there are mainline users after all, and they volunteer
to maintain the port in the future, the removal can be reverted.

Link: https://lore.kernel.org/linux-mm/YhdWNLUhk+x9RAzU@yamatobi.andestech.com/
Link: https://lore.kernel.org/lkml/20220302065213.82702-1-alankao@andestech.com/
Link: https://www.andestech.com/en/products-solutions/andestar-architecture/
Signed-off-by: Alan Kao <alankao@andestech.com>
[arnd: rewrite changelog to provide more background]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 0 insertions, 17 deletions

diff --git a/Documentation/devicetree/bindings/perf/nds32v3-pmu.txt b/Documentation/devicetree/bindings/perf/nds32v3-pmu.txt
deleted file mode 100644
index 1bd15785b4ae..000000000000
--- a/Documentation/devicetree/bindings/perf/nds32v3-pmu.txt
+++ /dev/null
@@ -1,17 +0,0 @@
-* NDS32 Performance Monitor Units
-
-NDS32 core have a PMU for counting cpu and cache events like cache misses.
-The NDS32 PMU representation in the device tree should be done as under:
-
-Required properties:
-
-- compatible :
-	"andestech,nds32v3-pmu"
-
-- interrupts : The interrupt number for NDS32 PMU is 13.
-
-Example:
-pmu{
-	compatible = "andestech,nds32v3-pmu";
-	interrupts = <13>;
-}