[PATCH v2 2/3] docs: riscv: hwprobe: Clarify misaligned keys are values not bitmasks

Yangyu Chen cyy at cyyself.name
Thu May 23 20:35:58 PDT 2024


The original documentation says hwprobe keys are bitmasks, but actually,
they are values. This patch clarifies this to avoid confusion.

Signed-off-by: Yangyu Chen <cyy at cyyself.name>
---
 Documentation/arch/riscv/hwprobe.rst | 31 ++++++++++++++++------------
 1 file changed, 18 insertions(+), 13 deletions(-)

diff --git a/Documentation/arch/riscv/hwprobe.rst b/Documentation/arch/riscv/hwprobe.rst
index d720712e9734..2e212956185d 100644
--- a/Documentation/arch/riscv/hwprobe.rst
+++ b/Documentation/arch/riscv/hwprobe.rst
@@ -192,25 +192,30 @@ The following keys are defined:
        supported as defined in the RISC-V ISA manual starting from commit
        d8ab5c78c207 ("Zihintpause is ratified").
 
-* :c:macro:`RISCV_HWPROBE_KEY_CPUPERF_0`: A bitmask that contains performance
+* :c:macro:`RISCV_HWPROBE_KEY_CPUPERF_0`: A value that contains performance
   information about the selected set of processors.
 
-  * :c:macro:`RISCV_HWPROBE_MISALIGNED_UNKNOWN`: The performance of misaligned
-    scalar accesses is unknown.
+  * :c:macro:`RISCV_HWPROBE_MISALIGNED_MASK`: The bitmask of the misaligned
+    access performance field in the value of key `RISCV_HWPROBE_KEY_CPUPERF_0`.
 
-  * :c:macro:`RISCV_HWPROBE_MISALIGNED_EMULATED`: Misaligned scalar accesses are
-    emulated via software, either in or below the kernel.  These accesses are
-    always extremely slow.
+    The following values (not bitmasks) in this field are defined:
 
-  * :c:macro:`RISCV_HWPROBE_MISALIGNED_SLOW`: Misaligned scalar 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_MISALIGNED_UNKNOWN`: The performance of misaligned
+      scalar accesses is unknown.
 
-  * :c:macro:`RISCV_HWPROBE_MISALIGNED_FAST`: Misaligned scalar accesses are
-    faster than equivalent byte accesses.
+    * :c:macro:`RISCV_HWPROBE_MISALIGNED_EMULATED`: Misaligned scalar accesses are
+      emulated via software, either in or below the kernel.  These accesses are
+      always extremely slow.
 
-  * :c:macro:`RISCV_HWPROBE_MISALIGNED_UNSUPPORTED`: Misaligned scalar accesses
-    are not supported at all and will generate a misaligned address fault.
+    * :c:macro:`RISCV_HWPROBE_MISALIGNED_SLOW`: Misaligned scalar 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_MISALIGNED_FAST`: Misaligned scalar accesses are
+      faster than equivalent byte accesses.
+
+    * :c:macro:`RISCV_HWPROBE_MISALIGNED_UNSUPPORTED`: Misaligned scalar accesses
+      are not supported at all and will generate a misaligned address fault.
 
 * :c:macro:`RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE`: An unsigned int which
   represents the size of the Zicboz block in bytes.
-- 
2.45.1




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