perf/x86: Expose CPUID enumeration bits for arch LBR

The LBR capabilities of Architecture LBR are retrieved from the CPUID
enumeration once at boot time. The capabilities have to be saved for
future usage.

Several new fields are added into structure x86_pmu to indicate the
capabilities. The fields will be used in the following patches.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1593780569-62993-9-git-send-email-kan.liang@linux.intel.com

arch/x86/events/perf_event.h

@@ -693,6 +693,19 @@ struct x86_pmu {
 	bool		lbr_double_abort;	   /* duplicated lbr aborts */
 	bool		lbr_pt_coexist;		   /* (LBR|BTS) may coexist with PT */
 
+	/*
+	 * Intel Architectural LBR CPUID Enumeration
+	 */
+	unsigned int	lbr_depth_mask:8;
+	unsigned int	lbr_deep_c_reset:1;
+	unsigned int	lbr_lip:1;
+	unsigned int	lbr_cpl:1;
+	unsigned int	lbr_filter:1;
+	unsigned int	lbr_call_stack:1;
+	unsigned int	lbr_mispred:1;
+	unsigned int	lbr_timed_lbr:1;
+	unsigned int	lbr_br_type:1;
+
 	void		(*lbr_reset)(void);
 	void		(*lbr_read)(struct cpu_hw_events *cpuc);
 	void		(*lbr_save)(void *ctx);

arch/x86/include/asm/perf_event.h

@@ -142,6 +142,46 @@ union cpuid10_edx {
 	unsigned int full;
 };
 
+/*
+ * Intel Architectural LBR CPUID detection/enumeration details:
+ */
+union cpuid28_eax {
+	struct {
+		/* Supported LBR depth values */
+		unsigned int	lbr_depth_mask:8;
+		unsigned int	reserved:22;
+		/* Deep C-state Reset */
+		unsigned int	lbr_deep_c_reset:1;
+		/* IP values contain LIP */
+		unsigned int	lbr_lip:1;
+	} split;
+	unsigned int		full;
+};
+
+union cpuid28_ebx {
+	struct {
+		/* CPL Filtering Supported */
+		unsigned int    lbr_cpl:1;
+		/* Branch Filtering Supported */
+		unsigned int    lbr_filter:1;
+		/* Call-stack Mode Supported */
+		unsigned int    lbr_call_stack:1;
+	} split;
+	unsigned int            full;
+};
+
+union cpuid28_ecx {
+	struct {
+		/* Mispredict Bit Supported */
+		unsigned int    lbr_mispred:1;
+		/* Timed LBRs Supported */
+		unsigned int    lbr_timed_lbr:1;
+		/* Branch Type Field Supported */
+		unsigned int    lbr_br_type:1;
+	} split;
+	unsigned int            full;
+};
+
 struct x86_pmu_capability {
 	int		version;
 	int		num_counters_gp;