riscv: cpufeature: extend riscv_cpufeature_patch_func to all ISA extensions

riscv_cpufeature_patch_func() currently only scans a limited set of
cpufeatures, explicitly defined with macros. Extend it to probe for all
ISA extensions.

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230128172856.3814-5-jszhang@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

1 files changed, 8 insertions, 56 deletions

diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index 59e20cad1b3d..6193f401f0c5 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -276,59 +276,11 @@ void __init riscv_fill_hwcap(void)
 }
 
 #ifdef CONFIG_RISCV_ALTERNATIVE
-static bool __init_or_module cpufeature_probe_svpbmt(unsigned int stage)
-{
-	if (!IS_ENABLED(CONFIG_RISCV_ISA_SVPBMT))
-		return false;
-
-	if (stage == RISCV_ALTERNATIVES_EARLY_BOOT)
-		return false;
-
-	return riscv_isa_extension_available(NULL, SVPBMT);
-}
-
-static bool __init_or_module cpufeature_probe_zicbom(unsigned int stage)
-{
-	if (!IS_ENABLED(CONFIG_RISCV_ISA_ZICBOM))
-		return false;
-
-	if (stage == RISCV_ALTERNATIVES_EARLY_BOOT)
-		return false;
-
-	if (!riscv_isa_extension_available(NULL, ZICBOM))
-		return false;
-
-	return true;
-}
-
-/*
- * Probe presence of individual extensions.
- *
- * This code may also be executed before kernel relocation, so we cannot use
- * addresses generated by the address-of operator as they won't be valid in
- * this context.
- * Tests, unless otherwise required, are to be added in alphabetical order.
- */
-static u32 __init_or_module cpufeature_probe(unsigned int stage)
-{
-	u32 cpu_req_feature = 0;
-
-	if (cpufeature_probe_svpbmt(stage))
-		cpu_req_feature |= BIT(CPUFEATURE_SVPBMT);
-
-	if (cpufeature_probe_zicbom(stage))
-		cpu_req_feature |= BIT(CPUFEATURE_ZICBOM);
-
-	return cpu_req_feature;
-}
-
 void __init_or_module riscv_cpufeature_patch_func(struct alt_entry *begin,
 						  struct alt_entry *end,
 						  unsigned int stage)
 {
-	u32 cpu_req_feature = cpufeature_probe(stage);
 	struct alt_entry *alt;
-	u32 tmp;
 
 	if (stage == RISCV_ALTERNATIVES_EARLY_BOOT)
 		return;
@@ -336,18 +288,18 @@ void __init_or_module riscv_cpufeature_patch_func(struct alt_entry *begin,
 	for (alt = begin; alt < end; alt++) {
 		if (alt->vendor_id != 0)
 			continue;
-		if (alt->errata_id >= CPUFEATURE_NUMBER) {
-			WARN(1, "This feature id:%d is not in kernel cpufeature list",
+		if (alt->errata_id >= RISCV_ISA_EXT_MAX) {
+			WARN(1, "This extension id:%d is not in ISA extension list",
 				alt->errata_id);
 			continue;
 		}
 
-		tmp = (1U << alt->errata_id);
-		if (cpu_req_feature & tmp) {
-			patch_text_nosync(alt->old_ptr, alt->alt_ptr, alt->alt_len);
-			riscv_alternative_fix_offsets(alt->old_ptr, alt->alt_len,
-						      alt->old_ptr - alt->alt_ptr);
-		}
+		if (!__riscv_isa_extension_available(NULL, alt->errata_id))
+			continue;
+
+		patch_text_nosync(alt->old_ptr, alt->alt_ptr, alt->alt_len);
+		riscv_alternative_fix_offsets(alt->old_ptr, alt->alt_len,
+					      alt->old_ptr - alt->alt_ptr);
 	}
 }
 #endif