perf: riscv_pmu{,_sbi}: Miscallenous improvement & fixes

A series of mostly-independent fixes and cleanups for the RISC-V PMU
drivers.

Link: https://lore.kernel.org/lkml/CAAhSdy23vE8+HxU5Jxy2rBMjy3rBTrJt_4sriuROac_sEESSVw@mail.gmail.com/T/#m9de15aef1b65ae6155fa33ea1239578ef463c2a2

* palmer/riscv-pmu:
  RISC-V: Improve SBI definitions
  RISC-V: Move counter info definition to sbi header file
  RISC-V: Fix SBI PMU calls for RV32
  RISC-V: Update user page mapping only once during start
  RISC-V: Fix counter restart during overflow for RV32

Author: palmer-dabbelt

arch/riscv/include/asm/sbi.h

@@ -122,7 +122,21 @@ enum sbi_ext_pmu_fid {
 	SBI_EXT_PMU_COUNTER_FW_READ,
 };
 
-#define RISCV_PMU_RAW_EVENT_MASK GENMASK_ULL(55, 0)
+union sbi_pmu_ctr_info {
+	unsigned long value;
+	struct {
+		unsigned long csr:12;
+		unsigned long width:6;
+#if __riscv_xlen == 32
+		unsigned long reserved:13;
+#else
+		unsigned long reserved:45;
+#endif
+		unsigned long type:1;
+	};
+};
+
+#define RISCV_PMU_RAW_EVENT_MASK GENMASK_ULL(47, 0)
 #define RISCV_PMU_RAW_EVENT_IDX 0x20000
 
 /** General pmu event codes specified in SBI PMU extension */
@@ -189,12 +203,26 @@ enum sbi_pmu_ctr_type {
 	SBI_PMU_CTR_TYPE_FW,
 };
 
+/* Helper macros to decode event idx */
+#define SBI_PMU_EVENT_IDX_OFFSET 20
+#define SBI_PMU_EVENT_IDX_MASK 0xFFFFF
+#define SBI_PMU_EVENT_IDX_CODE_MASK 0xFFFF
+#define SBI_PMU_EVENT_IDX_TYPE_MASK 0xF0000
+#define SBI_PMU_EVENT_RAW_IDX 0x20000
+#define SBI_PMU_FIXED_CTR_MASK 0x07
+
+#define SBI_PMU_EVENT_CACHE_ID_CODE_MASK 0xFFF8
+#define SBI_PMU_EVENT_CACHE_OP_ID_CODE_MASK 0x06
+#define SBI_PMU_EVENT_CACHE_RESULT_ID_CODE_MASK 0x01
+
+#define SBI_PMU_EVENT_IDX_INVALID 0xFFFFFFFF
+
 /* Flags defined for config matching function */
 #define SBI_PMU_CFG_FLAG_SKIP_MATCH	(1 << 0)
 #define SBI_PMU_CFG_FLAG_CLEAR_VALUE	(1 << 1)
 #define SBI_PMU_CFG_FLAG_AUTO_START	(1 << 2)
 #define SBI_PMU_CFG_FLAG_SET_VUINH	(1 << 3)
-#define SBI_PMU_CFG_FLAG_SET_VSNH	(1 << 4)
+#define SBI_PMU_CFG_FLAG_SET_VSINH	(1 << 4)
 #define SBI_PMU_CFG_FLAG_SET_UINH	(1 << 5)
 #define SBI_PMU_CFG_FLAG_SET_SINH	(1 << 6)
 #define SBI_PMU_CFG_FLAG_SET_MINH	(1 << 7)

drivers/perf/riscv_pmu.c

@@ -170,7 +170,6 @@ int riscv_pmu_event_set_period(struct perf_event *event)
 		left = (max_period >> 1);
 
 	local64_set(&hwc->prev_count, (u64)-left);
-	perf_event_update_userpage(event);
 
 	return overflow;
 }

drivers/perf/riscv_pmu_sbi.c

@@ -41,20 +41,6 @@ static const struct attribute_group *riscv_pmu_attr_groups[] = {
 	NULL,
 };
 
-union sbi_pmu_ctr_info {
-	unsigned long value;
-	struct {
-		unsigned long csr:12;
-		unsigned long width:6;
-#if __riscv_xlen == 32
-		unsigned long reserved:13;
-#else
-		unsigned long reserved:45;
-#endif
-		unsigned long type:1;
-	};
-};
-
 /*
  * RISC-V doesn't have hetergenous harts yet. This need to be part of
  * per_cpu in case of harts with different pmu counters
@@ -294,8 +280,13 @@ static int pmu_sbi_ctr_get_idx(struct perf_event *event)
 		cflags |= SBI_PMU_CFG_FLAG_SET_UINH;
 
 	/* retrieve the available counter index */
+#if defined(CONFIG_32BIT)
+	ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_CFG_MATCH, cbase, cmask,
+			cflags, hwc->event_base, hwc->config, hwc->config >> 32);
+#else
 	ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_CFG_MATCH, cbase, cmask,
 			cflags, hwc->event_base, hwc->config, 0);
+#endif
 	if (ret.error) {
 		pr_debug("Not able to find a counter for event %lx config %llx\n",
 			hwc->event_base, hwc->config);
@@ -437,8 +428,13 @@ static void pmu_sbi_ctr_start(struct perf_event *event, u64 ival)
 	struct hw_perf_event *hwc = &event->hw;
 	unsigned long flag = SBI_PMU_START_FLAG_SET_INIT_VALUE;
 
+#if defined(CONFIG_32BIT)
 	ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, hwc->idx,
 			1, flag, ival, ival >> 32, 0);
+#else
+	ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, hwc->idx,
+			1, flag, ival, 0, 0);
+#endif
 	if (ret.error && (ret.error != SBI_ERR_ALREADY_STARTED))
 		pr_err("Starting counter idx %d failed with error %d\n",
 			hwc->idx, sbi_err_map_linux_errno(ret.error));
@@ -545,8 +541,14 @@ static inline void pmu_sbi_start_overflow_mask(struct riscv_pmu *pmu,
 			hwc = &event->hw;
 			max_period = riscv_pmu_ctr_get_width_mask(event);
 			init_val = local64_read(&hwc->prev_count) & max_period;
+#if defined(CONFIG_32BIT)
+			sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, idx, 1,
+				  flag, init_val, init_val >> 32, 0);
+#else
 			sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, idx, 1,
 				  flag, init_val, 0, 0);
+#endif
+			perf_event_update_userpage(event);
 		}
 		ctr_ovf_mask = ctr_ovf_mask >> 1;
 		idx++;