perf/arm-cmn: Decouple wp_config registers from filter group number

Previously, wp_config0/2 registers were used for primary match group and
wp_config1/3 registers for secondary match group. In order to support
tertiary match group, this patch decouples the registers and the groups.

Signed-off-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>
Link: https://lore.kernel.org/r/20240618005056.3092866-2-ilkka@os.amperecomputing.com
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c
index e26ad1d3ed0bb73dcc92116cba47c4936d200b8d..f2349d23df57af9ee702bf6a5e380e8b9ee48b96 100644 (file)
--- a/drivers/perf/arm-cmn.c
+++ b/drivers/perf/arm-cmn.c
@@ -590,6 +590,13 @@ struct arm_cmn_hw_event {
        s8 dtc_idx[CMN_MAX_DTCS];
        u8 num_dns;
        u8 dtm_offset;
+
+       /*
+        * WP config registers are divided to UP and DOWN events. We need to
+        * keep to track only one of them.
+        */
+       DECLARE_BITMAP(wp_idx, CMN_MAX_XPS);
+
        bool wide_sel;
        enum cmn_filter_select filter_sel;
 };
@@ -617,6 +624,17 @@ static unsigned int arm_cmn_get_index(u64 x[], unsigned int pos)
        return (x[pos / 32] >> ((pos % 32) * 2)) & 3;
 }
 
+static void arm_cmn_set_wp_idx(unsigned long *wp_idx, unsigned int pos, bool val)
+{
+       if (val)
+               set_bit(pos, wp_idx);
+}
+
+static unsigned int arm_cmn_get_wp_idx(unsigned long *wp_idx, unsigned int pos)
+{
+       return test_bit(pos, wp_idx);
+}
+
 struct arm_cmn_event_attr {
        struct device_attribute attr;
        enum cmn_model model;
@@ -1336,9 +1354,34 @@ static const struct attribute_group *arm_cmn_attr_groups[] = {
        NULL
 };
 
-static int arm_cmn_wp_idx(struct perf_event *event)
+static int arm_cmn_find_free_wp_idx(struct arm_cmn_dtm *dtm,
+                                   struct perf_event *event)
+{
+       int wp_idx = CMN_EVENT_EVENTID(event);
+
+       if (dtm->wp_event[wp_idx] >= 0)
+               if (dtm->wp_event[++wp_idx] >= 0)
+                       return -ENOSPC;
+
+       return wp_idx;
+}
+
+static int arm_cmn_get_assigned_wp_idx(struct perf_event *event,
+                                      struct arm_cmn_hw_event *hw,
+                                      unsigned int pos)
 {
-       return CMN_EVENT_EVENTID(event) + CMN_EVENT_WP_GRP(event);
+       return CMN_EVENT_EVENTID(event) + arm_cmn_get_wp_idx(hw->wp_idx, pos);
+}
+
+static void arm_cmn_claim_wp_idx(struct arm_cmn_dtm *dtm,
+                                struct perf_event *event,
+                                unsigned int dtc, int wp_idx,
+                                unsigned int pos)
+{
+       struct arm_cmn_hw_event *hw = to_cmn_hw(event);
+
+       dtm->wp_event[wp_idx] = hw->dtc_idx[dtc];
+       arm_cmn_set_wp_idx(hw->wp_idx, pos, wp_idx - CMN_EVENT_EVENTID(event));
 }
 
 static u32 arm_cmn_wp_config(struct perf_event *event)
@@ -1520,12 +1563,12 @@ static void arm_cmn_event_start(struct perf_event *event, int flags)
                writeq_relaxed(CMN_CC_INIT, cmn->dtc[i].base + CMN_DT_PMCCNTR);
                cmn->dtc[i].cc_active = true;
        } else if (type == CMN_TYPE_WP) {
-               int wp_idx = arm_cmn_wp_idx(event);
                u64 val = CMN_EVENT_WP_VAL(event);
                u64 mask = CMN_EVENT_WP_MASK(event);
 
                for_each_hw_dn(hw, dn, i) {
                        void __iomem *base = dn->pmu_base + CMN_DTM_OFFSET(hw->dtm_offset);
+                       int wp_idx = arm_cmn_get_assigned_wp_idx(event, hw, i);
 
                        writeq_relaxed(val, base + CMN_DTM_WPn_VAL(wp_idx));
                        writeq_relaxed(mask, base + CMN_DTM_WPn_MASK(wp_idx));
@@ -1550,10 +1593,9 @@ static void arm_cmn_event_stop(struct perf_event *event, int flags)
                i = hw->dtc_idx[0];
                cmn->dtc[i].cc_active = false;
        } else if (type == CMN_TYPE_WP) {
-               int wp_idx = arm_cmn_wp_idx(event);
-
                for_each_hw_dn(hw, dn, i) {
                        void __iomem *base = dn->pmu_base + CMN_DTM_OFFSET(hw->dtm_offset);
+                       int wp_idx = arm_cmn_get_assigned_wp_idx(event, hw, i);
 
                        writeq_relaxed(0, base + CMN_DTM_WPn_MASK(wp_idx));
                        writeq_relaxed(~0ULL, base + CMN_DTM_WPn_VAL(wp_idx));
@@ -1571,10 +1613,23 @@ struct arm_cmn_val {
        u8 dtm_count[CMN_MAX_DTMS];
        u8 occupid[CMN_MAX_DTMS][SEL_MAX];
        u8 wp[CMN_MAX_DTMS][4];
+       u8 wp_combine[CMN_MAX_DTMS][2];
        int dtc_count[CMN_MAX_DTCS];
        bool cycles;
 };
 
+static int arm_cmn_val_find_free_wp_config(struct perf_event *event,
+                                         struct arm_cmn_val *val, int dtm)
+{
+       int wp_idx = CMN_EVENT_EVENTID(event);
+
+       if (val->wp[dtm][wp_idx])
+               if (val->wp[dtm][++wp_idx])
+                       return -ENOSPC;
+
+       return wp_idx;
+}
+
 static void arm_cmn_val_add_event(struct arm_cmn *cmn, struct arm_cmn_val *val,
                                  struct perf_event *event)
 {
@@ -1606,8 +1661,9 @@ static void arm_cmn_val_add_event(struct arm_cmn *cmn, struct arm_cmn_val *val,
                if (type != CMN_TYPE_WP)
                        continue;
 
-               wp_idx = arm_cmn_wp_idx(event);
-               val->wp[dtm][wp_idx] = CMN_EVENT_WP_COMBINE(event) + 1;
+               wp_idx = arm_cmn_val_find_free_wp_config(event, val, dtm);
+               val->wp[dtm][wp_idx] = 1;
+               val->wp_combine[dtm][wp_idx >> 1] += !!CMN_EVENT_WP_COMBINE(event);
        }
 }
 
@@ -1631,6 +1687,7 @@ static int arm_cmn_validate_group(struct arm_cmn *cmn, struct perf_event *event)
                return -ENOMEM;
 
        arm_cmn_val_add_event(cmn, val, leader);
+
        for_each_sibling_event(sibling, leader)
                arm_cmn_val_add_event(cmn, val, sibling);
 
@@ -1645,7 +1702,7 @@ static int arm_cmn_validate_group(struct arm_cmn *cmn, struct perf_event *event)
                        goto done;
 
        for_each_hw_dn(hw, dn, i) {
-               int wp_idx, wp_cmb, dtm = dn->dtm, sel = hw->filter_sel;
+               int wp_idx, dtm = dn->dtm, sel = hw->filter_sel;
 
                if (val->dtm_count[dtm] == CMN_DTM_NUM_COUNTERS)
                        goto done;
@@ -1657,12 +1714,12 @@ static int arm_cmn_validate_group(struct arm_cmn *cmn, struct perf_event *event)
                if (type != CMN_TYPE_WP)
                        continue;
 
-               wp_idx = arm_cmn_wp_idx(event);
-               if (val->wp[dtm][wp_idx])
+               wp_idx = arm_cmn_val_find_free_wp_config(event, val, dtm);
+               if (wp_idx < 0)
                        goto done;
 
-               wp_cmb = val->wp[dtm][wp_idx ^ 1];
-               if (wp_cmb && wp_cmb != CMN_EVENT_WP_COMBINE(event) + 1)
+               if (wp_idx & 1 &&
+                   val->wp_combine[dtm][wp_idx >> 1] != !!CMN_EVENT_WP_COMBINE(event))
                        goto done;
        }
 
@@ -1773,8 +1830,11 @@ static void arm_cmn_event_clear(struct arm_cmn *cmn, struct perf_event *event,
                struct arm_cmn_dtm *dtm = &cmn->dtms[hw->dn[i].dtm] + hw->dtm_offset;
                unsigned int dtm_idx = arm_cmn_get_index(hw->dtm_idx, i);
 
-               if (type == CMN_TYPE_WP)
-                       dtm->wp_event[arm_cmn_wp_idx(event)] = -1;
+               if (type == CMN_TYPE_WP) {
+                       int wp_idx = arm_cmn_get_assigned_wp_idx(event, hw, i);
+
+                       dtm->wp_event[wp_idx] = -1;
+               }
 
                if (hw->filter_sel > SEL_NONE)
                        hw->dn[i].occupid[hw->filter_sel].count--;
@@ -1783,6 +1843,7 @@ static void arm_cmn_event_clear(struct arm_cmn *cmn, struct perf_event *event,
                writel_relaxed(dtm->pmu_config_low, dtm->base + CMN_DTM_PMU_CONFIG);
        }
        memset(hw->dtm_idx, 0, sizeof(hw->dtm_idx));
+       memset(hw->wp_idx, 0, sizeof(hw->wp_idx));
 
        for_each_hw_dtc_idx(hw, j, idx)
                cmn->dtc[j].counters[idx] = NULL;
@@ -1836,10 +1897,11 @@ static int arm_cmn_event_add(struct perf_event *event, int flags)
                if (type == CMN_TYPE_XP) {
                        input_sel = CMN__PMEVCNT0_INPUT_SEL_XP + dtm_idx;
                } else if (type == CMN_TYPE_WP) {
-                       int tmp, wp_idx = arm_cmn_wp_idx(event);
+                       int tmp, wp_idx;
                        u32 cfg = arm_cmn_wp_config(event);
 
-                       if (dtm->wp_event[wp_idx] >= 0)
+                       wp_idx = arm_cmn_find_free_wp_idx(dtm, event);
+                       if (wp_idx < 0)
                                goto free_dtms;
 
                        tmp = dtm->wp_event[wp_idx ^ 1];
@@ -1848,7 +1910,8 @@ static int arm_cmn_event_add(struct perf_event *event, int flags)
                                goto free_dtms;
 
                        input_sel = CMN__PMEVCNT0_INPUT_SEL_WP + wp_idx;
-                       dtm->wp_event[wp_idx] = hw->dtc_idx[d];
+
+                       arm_cmn_claim_wp_idx(dtm, event, d, wp_idx, i);
                        writel_relaxed(cfg, dtm->base + CMN_DTM_WPn_CONFIG(wp_idx));
                } else {
                        struct arm_cmn_nodeid nid = arm_cmn_nid(cmn, dn->id);