drm/msm: Add PERFCNTR_CONFIG ioctl

Add new UABI and implementation of PERFCNTR_CONFIG ioctl.

A bit more work is required to configure the pwrup_reglist for the GMU
to restore SELect regs on exit of IFPC, before we can stop disabling
IFPC while global counter collection.  This will follow in a later
commit, but will be transparent to userspace.

Signed-off-by: Rob Clark <robin.clark@oss.qualcomm.com>
Reviewed-by: Anna Maniscalco <anna.maniscalco2000@gmail.com>
Reviewed-by: Akhil P Oommen <akhilpo@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/728217/
Message-ID: <20260526145137.160554-14-robin.clark@oss.qualcomm.com>

1 files changed, 48 insertions, 0 deletions

diff --git a/include/uapi/drm/msm_drm.h b/include/uapi/drm/msm_drm.h
index b99098792371..7f2e594be4eb 100644
--- a/include/uapi/drm/msm_drm.h
+++ b/include/uapi/drm/msm_drm.h
@@ -491,6 +491,52 @@ struct drm_msm_submitqueue_query {
 	__u32 pad;
 };
 
+#define MSM_PERFCNTR_STREAM	0x00000001
+#define MSM_PERFCNTR_UPDATE	0x00000002
+#define MSM_PERFCNTR_FLAGS	( \
+		MSM_PERFCNTR_STREAM | \
+		MSM_PERFCNTR_UPDATE | \
+		0)
+
+struct drm_msm_perfcntr_group {
+	char group_name[16];
+	__u32 nr_countables;
+	__u32 pad;         /* mbz */
+	__u64 countables;  /* pointer to an array of nr_countables u32 */
+};
+
+/*
+ * Note, for MSM_PERFCNTR_STREAM, the ioctl returns an fd to read recorded
+ * counters.  This only works because the ioctl is DRM_IOW(), if we returned
+ * a out param in the ioctl struct the copy_to_user() (in drm_ioctl())
+ * could fault, causing us to leak the fd.
+ *
+ * If the ioctl returns with error E2BIG, that means more counters/countables
+ * are requested than are currently available.  If MSM_PERFCNTR_UPDATE flag
+ * is set, drm_msm_perfcntr_group::nr_countables will be updated to return
+ * the actual # of counters available.
+ *
+ * The data read from the has the following format for each sampling period:
+ *
+ *     uint64_t timestamp;  // CP_ALWAYS_ON_COUNTER captured at sample time
+ *     uint32_t seqno;      // increments by 1 each period, reset to 0 on discontinuity
+ *     uint32_t mbz;        // pad out counters to 64b
+ *     struct {
+ *        uint64_t counter[nr_countables];
+ *     } groups[nr_groups];
+ *
+ * The ordering of groups and counters matches the order in PERFCNTR_CONFIG
+ * ioctl.
+ */
+struct drm_msm_perfcntr_config {
+	__u32 flags;         /* bitmask of MSM_PERFCNTR_x */
+	__u32 nr_groups;     /* # of entries in groups array */
+	__u64 groups;        /* pointer to array of drm_msm_perfcntr_group */
+	__u64 period;        /* sampling period in ns */
+	__u32 bufsz_shift;   /* sample buffer size in bytes is 1<<bufsz_shift */
+	__u32 group_stride;  /* sizeof(struct drm_msm_perfcntr_group) */
+};
+
 #define DRM_MSM_GET_PARAM              0x00
 #define DRM_MSM_SET_PARAM              0x01
 #define DRM_MSM_GEM_NEW                0x02
@@ -507,6 +553,7 @@ struct drm_msm_submitqueue_query {
 #define DRM_MSM_SUBMITQUEUE_CLOSE      0x0B
 #define DRM_MSM_SUBMITQUEUE_QUERY      0x0C
 #define DRM_MSM_VM_BIND                0x0D
+#define DRM_MSM_PERFCNTR_CONFIG        0x0E
 
 #define DRM_IOCTL_MSM_GET_PARAM        DRM_IOWR(DRM_COMMAND_BASE + DRM_MSM_GET_PARAM, struct drm_msm_param)
 #define DRM_IOCTL_MSM_SET_PARAM        DRM_IOW (DRM_COMMAND_BASE + DRM_MSM_SET_PARAM, struct drm_msm_param)
@@ -521,6 +568,7 @@ struct drm_msm_submitqueue_query {
 #define DRM_IOCTL_MSM_SUBMITQUEUE_CLOSE  DRM_IOW (DRM_COMMAND_BASE + DRM_MSM_SUBMITQUEUE_CLOSE, __u32)
 #define DRM_IOCTL_MSM_SUBMITQUEUE_QUERY  DRM_IOW (DRM_COMMAND_BASE + DRM_MSM_SUBMITQUEUE_QUERY, struct drm_msm_submitqueue_query)
 #define DRM_IOCTL_MSM_VM_BIND          DRM_IOWR(DRM_COMMAND_BASE + DRM_MSM_VM_BIND, struct drm_msm_vm_bind)
+#define DRM_IOCTL_MSM_PERFCNTR_CONFIG  DRM_IOW (DRM_COMMAND_BASE + DRM_MSM_PERFCNTR_CONFIG, struct drm_msm_perfcntr_config)
 
 #if defined(__cplusplus)
 }