[PATCH v4 07/16] riscv: cpufeature: Extract common elements from extension checking

Charlie Jenkins
2024-04-26T21:29:41Z

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>
---
arch/riscv/include/asm/cpufeature.h | 78 +++++++++++++++++-------------
arch/riscv/include/asm/vendor_extensions.h | 28 -----------
2 files changed, 44 insertions(+), 62 deletions(-)

diff --git a/arch/riscv/include/asm/cpufeature.h b/arch/riscv/include/asm/cpufeature.h
index fedd479ccfd1..17896ec9ec11 100644
--- a/arch/riscv/include/asm/cpufeature.h
+++ b/arch/riscv/include/asm/cpufeature.h
@@ -98,59 +98,66 @@ extern bool riscv_isa_fallback;

unsigned long riscv_isa_extension_base(const unsigned long *isa_bitmap);

+#define EXT_ALL_VENDORS 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(EXT_ALL_VENDORS, 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(EXT_ALL_VENDORS, 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(EXT_ALL_VENDORS, ext))
return true;

return __riscv_isa_extension_available(hart_isa[cpu].isa, ext);
@@ -158,7 +165,10 @@ 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(EXT_ALL_VENDORS, 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 74b82433e0a2..880bb86ec890 100644
--- a/arch/riscv/include/asm/vendor_extensions.h
+++ b/arch/riscv/include/asm/vendor_extensions.h
@@ -39,34 +39,6 @@ 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)
{

--
2.44.0