RISC-V: alternative: Remove feature_probe_func

Now that we're testing unaligned memory copy and making that
determination generically, there are no more users of the vendor
feature_probe_func(). While I think it's probably going to need to come
back, there are no users right now, so let's remove it until it's
needed.

Signed-off-by: Evan Green <evan@rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230818194136.4084400-3-evan@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

arch/riscv/errata/thead/errata.c

@@ -120,11 +120,3 @@ void thead_errata_patch_func(struct alt_entry *begin, struct alt_entry *end,
 	if (stage == RISCV_ALTERNATIVES_EARLY_BOOT)
 		local_flush_icache_all();
 }
-
-void thead_feature_probe_func(unsigned int cpu,
-			      unsigned long archid,
-			      unsigned long impid)
-{
-	if ((archid == 0) && (impid == 0))
-		per_cpu(misaligned_access_speed, cpu) = RISCV_HWPROBE_MISALIGNED_FAST;
-}

arch/riscv/include/asm/alternative.h

@@ -30,7 +30,6 @@
 #define ALT_OLD_PTR(a)			__ALT_PTR(a, old_offset)
 #define ALT_ALT_PTR(a)			__ALT_PTR(a, alt_offset)
 
-void probe_vendor_features(unsigned int cpu);
 void __init apply_boot_alternatives(void);
 void __init apply_early_boot_alternatives(void);
 void apply_module_alternatives(void *start, size_t length);
@@ -53,15 +52,11 @@ void thead_errata_patch_func(struct alt_entry *begin, struct alt_entry *end,
 			     unsigned long archid, unsigned long impid,
 			     unsigned int stage);
 
-void thead_feature_probe_func(unsigned int cpu, unsigned long archid,
-			      unsigned long impid);
-
 void riscv_cpufeature_patch_func(struct alt_entry *begin, struct alt_entry *end,
 				 unsigned int stage);
 
 #else /* CONFIG_RISCV_ALTERNATIVE */
 
-static inline void probe_vendor_features(unsigned int cpu) { }
 static inline void apply_boot_alternatives(void) { }
 static inline void apply_early_boot_alternatives(void) { }
 static inline void apply_module_alternatives(void *start, size_t length) { }

arch/riscv/kernel/alternative.c

@@ -27,8 +27,6 @@ struct cpu_manufacturer_info_t {
 	void (*patch_func)(struct alt_entry *begin, struct alt_entry *end,
 				  unsigned long archid, unsigned long impid,
 				  unsigned int stage);
-	void (*feature_probe_func)(unsigned int cpu, unsigned long archid,
-				   unsigned long impid);
 };
 
 static void riscv_fill_cpu_mfr_info(struct cpu_manufacturer_info_t *cpu_mfr_info)
@@ -43,7 +41,6 @@ static void riscv_fill_cpu_mfr_info(struct cpu_manufacturer_info_t *cpu_mfr_info
 	cpu_mfr_info->imp_id = sbi_get_mimpid();
 #endif
 
-	cpu_mfr_info->feature_probe_func = NULL;
 	switch (cpu_mfr_info->vendor_id) {
 #ifdef CONFIG_ERRATA_SIFIVE
 	case SIFIVE_VENDOR_ID:
@@ -53,7 +50,6 @@ static void riscv_fill_cpu_mfr_info(struct cpu_manufacturer_info_t *cpu_mfr_info
 #ifdef CONFIG_ERRATA_THEAD
 	case THEAD_VENDOR_ID:
 		cpu_mfr_info->patch_func = thead_errata_patch_func;
-		cpu_mfr_info->feature_probe_func = thead_feature_probe_func;
 		break;
 #endif
 	default:
@@ -143,20 +139,6 @@ void riscv_alternative_fix_offsets(void *alt_ptr, unsigned int len,
 	}
 }
 
-/* Called on each CPU as it starts */
-void probe_vendor_features(unsigned int cpu)
-{
-	struct cpu_manufacturer_info_t cpu_mfr_info;
-
-	riscv_fill_cpu_mfr_info(&cpu_mfr_info);
-	if (!cpu_mfr_info.feature_probe_func)
-		return;
-
-	cpu_mfr_info.feature_probe_func(cpu,
-					cpu_mfr_info.arch_id,
-					cpu_mfr_info.imp_id);
-}
-
 /*
  * This is called very early in the boot process (directly after we run
  * a feature detect on the boot CPU). No need to worry about other CPUs
@@ -211,7 +193,6 @@ void __init apply_boot_alternatives(void)
 	/* If called on non-boot cpu things could go wrong */
 	WARN_ON(smp_processor_id() != 0);
 
-	probe_vendor_features(0);
 	_apply_alternatives((struct alt_entry *)__alt_start,
 			    (struct alt_entry *)__alt_end,
 			    RISCV_ALTERNATIVES_BOOT);

arch/riscv/kernel/smpboot.c

@@ -247,7 +247,6 @@ asmlinkage __visible void smp_callin(void)
 	numa_add_cpu(curr_cpuid);
 	set_cpu_online(curr_cpuid, 1);
 	check_unaligned_access(curr_cpuid);
-	probe_vendor_features(curr_cpuid);
 
 	if (has_vector()) {
 		if (riscv_v_setup_vsize())