[PATCH v6 08/17] riscv: cpufeature: Extract common elements from extension checking

[Charlie Jenkins]

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 at rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley at microchip.com>
---
 arch/riscv/include/asm/cpufeature.h        | 78 +++++++++++++++++-------------
 arch/riscv/include/asm/vendor_extensions.h | 28 -----------
 arch/riscv/kernel/vendor_extensions.c      | 16 +++---
 3 files changed, 51 insertions(+), 71 deletions(-)

diff --git a/arch/riscv/include/asm/cpufeature.h b/arch/riscv/include/asm/cpufeature.h
index fedd479ccfd1..88723ac2d26e 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 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);
@@ -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(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 a6959836f895..d21e411d7338 100644
--- a/arch/riscv/include/asm/vendor_extensions.h
+++ b/arch/riscv/include/asm/vendor_extensions.h
@@ -47,34 +47,6 @@ 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)
 {
diff --git a/arch/riscv/kernel/vendor_extensions.c b/arch/riscv/kernel/vendor_extensions.c
index e4ef574b7d08..7910890c17de 100644
--- a/arch/riscv/kernel/vendor_extensions.c
+++ b/arch/riscv/kernel/vendor_extensions.c
@@ -31,16 +31,14 @@ const size_t riscv_isa_vendor_ext_list_size = ARRAY_SIZE(riscv_isa_vendor_ext_li
  */
 bool __riscv_isa_vendor_extension_available(int cpu, unsigned long vendor, unsigned int bit)
 {
-	unsigned long *bmap;
-	struct riscv_isainfo *cpu_bmap;
-	size_t bmap_size;
+	struct riscv_isavendorinfo *bmap;
+	struct riscv_isavendorinfo *cpu_bmap;
 
 	switch (vendor) {
 #ifdef CONFIG_RISCV_ISA_VENDOR_EXT_THEAD
 	case THEAD_VENDOR_ID:
-		bmap = riscv_isa_vendor_ext_list_thead.vendor_bitmap;
-		cpu_bmap = riscv_isa_vendor_ext_list_thead.per_hart_vendor_bitmap;
-		bmap_size = riscv_isa_vendor_ext_list_thead.bitmap_size;
+		bmap = &riscv_isa_vendor_ext_list_thead.all_harts_isa_bitmap;
+		cpu_bmap = &riscv_isa_vendor_ext_list_thead.per_hart_isa_bitmap[cpu];
 		break;
 #endif
 	default:
@@ -48,11 +46,11 @@ bool __riscv_isa_vendor_extension_available(int cpu, unsigned long vendor, unsig
 	}
 
 	if (cpu != -1)
-		bmap = cpu_bmap[cpu].isa;
+		bmap = &cpu_bmap[cpu];
 
-	if (bit >= bmap_size)
+	if (bit >= RISCV_ISA_VENDOR_EXT_MAX)
 		return false;
 
-	return test_bit(bit, bmap) ? true : false;
+	return test_bit(bit, bmap->isa) ? true : false;
 }
 EXPORT_SYMBOL_GPL(__riscv_isa_vendor_extension_available);

-- 
2.44.0