riscv: cpufeature: Extract common elements from extension checking

The __riscv_has_extension_likely() and __riscv_has_extension_unlikely()
functions from the vendor_extensions.h can be used to simplify the
standard extension checking code as well. Migrate those functions to
cpufeature.h and reorganize the code in the file to use the functions.

Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Andy Chiu <andy.chiu@sifive.com>
Link: https://lore.kernel.org/r/20240719-support_vendor_extensions-v3-4-0af7587bbec0@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

diff --git a/arch/riscv/include/asm/cpufeature.h b/arch/riscv/include/asm/cpufeature.h
index bfe7c0b881e9f135b7237c88a9c9f889f05b04e1..45f9c1171a486a4dc6a4e0c80d64bf80a724b48f 100644 (file)
--- a/arch/riscv/include/asm/cpufeature.h
+++ b/arch/riscv/include/asm/cpufeature.h
@@ -104,59 +104,66 @@ extern bool riscv_isa_fallback;
 
 unsigned long riscv_isa_extension_base(const unsigned long *isa_bitmap);
 
+#define STANDARD_EXT           0
+
 bool __riscv_isa_extension_available(const unsigned long *isa_bitmap, unsigned int bit);
 #define riscv_isa_extension_available(isa_bitmap, ext) \
        __riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_##ext)
 
-static __always_inline bool
-riscv_has_extension_likely(const unsigned long ext)
+static __always_inline bool __riscv_has_extension_likely(const unsigned long vendor,
+                                                        const unsigned long ext)
 {
-       compiletime_assert(ext < RISCV_ISA_EXT_MAX,
-                          "ext must be < RISCV_ISA_EXT_MAX");
-
-       if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE)) {
-               asm goto(
-               ALTERNATIVE("j  %l[l_no]", "nop", 0, %[ext], 1)
-               :
-               : [ext] "i" (ext)
-               :
-               : l_no);
-       } else {
-               if (!__riscv_isa_extension_available(NULL, ext))
-                       goto l_no;
-       }
+       asm goto(ALTERNATIVE("j %l[l_no]", "nop", %[vendor], %[ext], 1)
+       :
+       : [vendor] "i" (vendor), [ext] "i" (ext)
+       :
+       : l_no);
 
        return true;
 l_no:
        return false;
 }
 
-static __always_inline bool
-riscv_has_extension_unlikely(const unsigned long ext)
+static __always_inline bool __riscv_has_extension_unlikely(const unsigned long vendor,
+                                                          const unsigned long ext)
 {
-       compiletime_assert(ext < RISCV_ISA_EXT_MAX,
-                          "ext must be < RISCV_ISA_EXT_MAX");
-
-       if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE)) {
-               asm goto(
-               ALTERNATIVE("nop", "j   %l[l_yes]", 0, %[ext], 1)
-               :
-               : [ext] "i" (ext)
-               :
-               : l_yes);
-       } else {
-               if (__riscv_isa_extension_available(NULL, ext))
-                       goto l_yes;
-       }
+       asm goto(ALTERNATIVE("nop", "j  %l[l_yes]", %[vendor], %[ext], 1)
+       :
+       : [vendor] "i" (vendor), [ext] "i" (ext)
+       :
+       : l_yes);
 
        return false;
 l_yes:
        return true;
 }
 
+static __always_inline bool riscv_has_extension_unlikely(const unsigned long ext)
+{
+       compiletime_assert(ext < RISCV_ISA_EXT_MAX, "ext must be < RISCV_ISA_EXT_MAX");
+
+       if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE))
+               return __riscv_has_extension_unlikely(STANDARD_EXT, ext);
+
+       return __riscv_isa_extension_available(NULL, ext);
+}
+
+static __always_inline bool riscv_has_extension_likely(const unsigned long ext)
+{
+       compiletime_assert(ext < RISCV_ISA_EXT_MAX, "ext must be < RISCV_ISA_EXT_MAX");
+
+       if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE))
+               return __riscv_has_extension_likely(STANDARD_EXT, ext);
+
+       return __riscv_isa_extension_available(NULL, ext);
+}
+
 static __always_inline bool riscv_cpu_has_extension_likely(int cpu, const unsigned long ext)
 {
-       if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE) && riscv_has_extension_likely(ext))
+       compiletime_assert(ext < RISCV_ISA_EXT_MAX, "ext must be < RISCV_ISA_EXT_MAX");
+
+       if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE) &&
+           __riscv_has_extension_likely(STANDARD_EXT, ext))
                return true;
 
        return __riscv_isa_extension_available(hart_isa[cpu].isa, ext);
@@ -164,7 +171,10 @@ static __always_inline bool riscv_cpu_has_extension_likely(int cpu, const unsign
 
 static __always_inline bool riscv_cpu_has_extension_unlikely(int cpu, const unsigned long ext)
 {
-       if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE) && riscv_has_extension_unlikely(ext))
+       compiletime_assert(ext < RISCV_ISA_EXT_MAX, "ext must be < RISCV_ISA_EXT_MAX");
+
+       if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE) &&
+           __riscv_has_extension_unlikely(STANDARD_EXT, ext))
                return true;
 
        return __riscv_isa_extension_available(hart_isa[cpu].isa, ext);

diff --git a/arch/riscv/include/asm/vendor_extensions.h b/arch/riscv/include/asm/vendor_extensions.h
index 04d72b02ae6b934e75b09117a0e6d4be843a0462..7437304a71b9111c80f5862aa5df6e58d86f73e0 100644 (file)
--- a/arch/riscv/include/asm/vendor_extensions.h
+++ b/arch/riscv/include/asm/vendor_extensions.h
@@ -48,34 +48,6 @@ bool __riscv_isa_vendor_extension_available(int cpu, unsigned long vendor, unsig
        __riscv_isa_vendor_extension_available(VENDOR_EXT_ALL_CPUS, vendor, \
                                               RISCV_ISA_VENDOR_EXT_##ext)
 
-static __always_inline bool __riscv_has_extension_likely(const unsigned long vendor,
-                                                        const unsigned long ext)
-{
-       asm goto(ALTERNATIVE("j %l[l_no]", "nop", %[vendor], %[ext], 1)
-       :
-       : [vendor] "i" (vendor), [ext] "i" (ext)
-       :
-       : l_no);
-
-       return true;
-l_no:
-       return false;
-}
-
-static __always_inline bool __riscv_has_extension_unlikely(const unsigned long vendor,
-                                                          const unsigned long ext)
-{
-       asm goto(ALTERNATIVE("nop", "j  %l[l_yes]", %[vendor], %[ext], 1)
-       :
-       : [vendor] "i" (vendor), [ext] "i" (ext)
-       :
-       : l_yes);
-
-       return false;
-l_yes:
-       return true;
-}
-
 static __always_inline bool riscv_has_vendor_extension_likely(const unsigned long vendor,
                                                              const unsigned long ext)
 {