[PATCH v10 loongarch-next 1/3] LoongArch: Add SCQ support detection

[George Guo <dongtai.guo@linux.dev>]

Check CPUCFG2_SCQ bit to determine if the CPU supports
SCQ instruction.

Co-developed-by: Yangyang Lian <lianyangyang@kylinos.cn>
Signed-off-by: Yangyang Lian <lianyangyang@kylinos.cn>
Reviewed-by: Hengqi Chen <hengqi.chen@gmail.com>
Tested-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: George Guo <guodongtai@kylinos.cn>
---
 arch/loongarch/include/asm/cpu-features.h | 1 +
 arch/loongarch/include/asm/cpu.h          | 2 ++
 arch/loongarch/include/uapi/asm/hwcap.h   | 1 +
 arch/loongarch/kernel/cpu-probe.c         | 4 ++++
 arch/loongarch/kernel/proc.c              | 1 +
 5 files changed, 9 insertions(+)

diff --git a/arch/loongarch/include/asm/cpu-features.h b/arch/loongarch/include/asm/cpu-features.h
index 3745d991a99a..39c7fe64c3ef 100644
--- a/arch/loongarch/include/asm/cpu-features.h
+++ b/arch/loongarch/include/asm/cpu-features.h
@@ -67,5 +67,6 @@
 #define cpu_has_msgint		cpu_opt(LOONGARCH_CPU_MSGINT)
 #define cpu_has_avecint		cpu_opt(LOONGARCH_CPU_AVECINT)
 #define cpu_has_redirectint	cpu_opt(LOONGARCH_CPU_REDIRECTINT)
+#define cpu_has_scq		cpu_opt(LOONGARCH_CPU_SCQ)
 
 #endif /* __ASM_CPU_FEATURES_H */
diff --git a/arch/loongarch/include/asm/cpu.h b/arch/loongarch/include/asm/cpu.h
index f3efb00b6141..5531039027ec 100644
--- a/arch/loongarch/include/asm/cpu.h
+++ b/arch/loongarch/include/asm/cpu.h
@@ -125,6 +125,7 @@ static inline char *id_to_core_name(unsigned int id)
 #define CPU_FEATURE_MSGINT		29	/* CPU has MSG interrupt */
 #define CPU_FEATURE_AVECINT		30	/* CPU has AVEC interrupt */
 #define CPU_FEATURE_REDIRECTINT		31	/* CPU has interrupt remapping */
+#define CPU_FEATURE_SCQ			32	/* CPU has SC.Q instruction */
 
 #define LOONGARCH_CPU_CPUCFG		BIT_ULL(CPU_FEATURE_CPUCFG)
 #define LOONGARCH_CPU_LAM		BIT_ULL(CPU_FEATURE_LAM)
@@ -158,5 +159,6 @@ static inline char *id_to_core_name(unsigned int id)
 #define LOONGARCH_CPU_MSGINT		BIT_ULL(CPU_FEATURE_MSGINT)
 #define LOONGARCH_CPU_AVECINT		BIT_ULL(CPU_FEATURE_AVECINT)
 #define LOONGARCH_CPU_REDIRECTINT	BIT_ULL(CPU_FEATURE_REDIRECTINT)
+#define LOONGARCH_CPU_SCQ		BIT_ULL(CPU_FEATURE_SCQ)
 
 #endif /* _ASM_CPU_H */
diff --git a/arch/loongarch/include/uapi/asm/hwcap.h b/arch/loongarch/include/uapi/asm/hwcap.h
index 2b34e56cfa9e..a3c570d407b9 100644
--- a/arch/loongarch/include/uapi/asm/hwcap.h
+++ b/arch/loongarch/include/uapi/asm/hwcap.h
@@ -18,5 +18,6 @@
 #define HWCAP_LOONGARCH_LBT_MIPS	(1 << 12)
 #define HWCAP_LOONGARCH_PTW		(1 << 13)
 #define HWCAP_LOONGARCH_LSPW		(1 << 14)
+#define HWCAP_LOONGARCH_CPU_SCQ		(1 << 15)
 
 #endif /* _UAPI_ASM_HWCAP_H */
diff --git a/arch/loongarch/kernel/cpu-probe.c b/arch/loongarch/kernel/cpu-probe.c
index 08a227034042..7c7708ce4063 100644
--- a/arch/loongarch/kernel/cpu-probe.c
+++ b/arch/loongarch/kernel/cpu-probe.c
@@ -177,6 +177,10 @@ static void cpu_probe_common(struct cpuinfo_loongarch *c)
 		c->options |= LOONGARCH_CPU_LAM;
 		elf_hwcap |= HWCAP_LOONGARCH_LAM;
 	}
+	if (config & CPUCFG2_SCQ) {
+		c->options |= LOONGARCH_CPU_SCQ;
+		elf_hwcap |= HWCAP_LOONGARCH_CPU_SCQ;
+	}
 	if (config & CPUCFG2_FP) {
 		c->options |= LOONGARCH_CPU_FPU;
 		elf_hwcap |= HWCAP_LOONGARCH_FPU;
diff --git a/arch/loongarch/kernel/proc.c b/arch/loongarch/kernel/proc.c
index a8800d20e11b..a60471b96440 100644
--- a/arch/loongarch/kernel/proc.c
+++ b/arch/loongarch/kernel/proc.c
@@ -62,6 +62,7 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 	seq_printf(m, "Features\t\t:");
 	if (cpu_has_cpucfg)	seq_printf(m, " cpucfg");
 	if (cpu_has_lam)	seq_printf(m, " lam");
+	if (cpu_has_scq)	seq_printf(m, " scq");
 	if (cpu_has_ual)	seq_printf(m, " ual");
 	if (cpu_has_fpu)	seq_printf(m, " fpu");
 	if (cpu_has_lsx)	seq_printf(m, " lsx");
-- 
2.49.0