[PATCH v3 8/8] RISC-V: hwprobe: Document unaligned vector perf key

[Jesse Taube]

Document key for reporting the speed of unaligned vector accesses.
The descriptions are the same as the scalar equivalent values.

Signed-off-by: Jesse Taube <jesse at rivosinc.com>
---
V1 -> V2:
  - New patch
V2 -> V3:
 - Specify access width
---
 Documentation/arch/riscv/hwprobe.rst | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/Documentation/arch/riscv/hwprobe.rst b/Documentation/arch/riscv/hwprobe.rst
index 7085a694b801..d102b4a16d55 100644
--- a/Documentation/arch/riscv/hwprobe.rst
+++ b/Documentation/arch/riscv/hwprobe.rst
@@ -236,3 +236,19 @@ The following keys are defined:
 
 * :c:macro:`RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE`: An unsigned int which
   represents the size of the Zicboz block in bytes.
+
+* :c:macro:`RISCV_HWPROBE_KEY_VEC_MISALIGNED_PERF`: An enum value describing the
+  performance of misaligned vector accesses on the selected set of processors.
+
+  * :c:macro:`RISCV_HWPROBE_VEC_MISALIGNED_UNKNOWN`: The performance of misaligned
+    accesses is unknown.
+
+  * :c:macro:`RISCV_HWPROBE_VEC_MISALIGNED_SLOW`: 32bit 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_VEC_MISALIGNED_FAST`: 32bit misaligned accesses are faster
+    than equivalent byte accesses.
+
+  * :c:macro:`RISCV_HWPROBE_VEC_MISALIGNED_UNSUPPORTED`: Misaligned accesses are
+    not supported at all and will generate a misaligned address fault.
-- 
2.45.2