---
drivers/gpu/drm/i915/i915_query.c | 148 ++++++++++++++++++++++++++++++
include/uapi/drm/i915_drm.h | 52 +++++++++++
2 files changed, 200 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_query.c b/drivers/gpu/drm/i915/i915_query.c
index fed337ad7b68..357c44e8177c 100644
--- a/drivers/gpu/drm/i915/i915_query.c
+++ b/drivers/gpu/drm/i915/i915_query.c
@@ -6,6 +6,8 @@
#include <linux/nospec.h>
+#include "gt/intel_engine_pm.h"
+#include "gt/intel_engine_user.h"
#include "i915_drv.h"
#include "i915_perf.h"
#include "i915_query.h"
@@ -90,6 +92,151 @@ static int query_topology_info(struct drm_i915_private *dev_priv,
return total_length;
}
+typedef u64 (*__ktime_func_t)(void);
+static __ktime_func_t __clock_id_to_func(clockid_t clk_id)
+{
+ /*
+ * Use logic same as the perf subsystem to allow user to select the
+ * reference clock id to be used for timestamps.
+ */
+ switch (clk_id) {
+ case CLOCK_MONOTONIC:
+ return &ktime_get_ns;
+ case CLOCK_MONOTONIC_RAW:
+ return &ktime_get_raw_ns;
+ case CLOCK_REALTIME:
+ return &ktime_get_real_ns;
+ case CLOCK_BOOTTIME:
+ return &ktime_get_boottime_ns;
+ case CLOCK_TAI:
+ return &ktime_get_clocktai_ns;
+ default:
+ return NULL;
+ }
+}
+
+static inline int
+__read_timestamps(struct intel_uncore *uncore,
+ i915_reg_t lower_reg,
+ i915_reg_t upper_reg,
+ u64 *cs_ts,
+ u64 *cpu_ts,
+ u64 *cpu_delta,
+ __ktime_func_t cpu_clock)
+{
+ u32 upper, lower, old_upper, loop = 0;
+
+ upper = intel_uncore_read_fw(uncore, upper_reg);
+ do {
+ *cpu_delta = local_clock();
+ *cpu_ts = cpu_clock();
+ lower = intel_uncore_read_fw(uncore, lower_reg);
+ *cpu_delta = local_clock() - *cpu_delta;
+ old_upper = upper;
+ upper = intel_uncore_read_fw(uncore, upper_reg);
+ } while (upper != old_upper && loop++ < 2);
+
+ *cs_ts = (u64)upper << 32 | lower;
+
+ return 0;
+}
+
+static int
+__query_cs_cycles(struct intel_engine_cs *engine,
+ u64 *cs_ts, u64 *cpu_ts, u64 *cpu_delta,
+ __ktime_func_t cpu_clock)
+{
+ struct intel_uncore *uncore = engine->uncore;
+ enum forcewake_domains fw_domains;
+ u32 base = engine->mmio_base;
+ intel_wakeref_t wakeref;
+ int ret;
+
+ fw_domains = intel_uncore_forcewake_for_reg(uncore,
+ RING_TIMESTAMP(base),
+ FW_REG_READ);
+
+ with_intel_runtime_pm(uncore->rpm, wakeref) {
+ spin_lock_irq(&uncore->lock);
+ intel_uncore_forcewake_get__locked(uncore, fw_domains);
+
+ ret = __read_timestamps(uncore,
+ RING_TIMESTAMP(base),
+ RING_TIMESTAMP_UDW(base),
+ cs_ts,
+ cpu_ts,
+ cpu_delta,
+ cpu_clock);
+
+ intel_uncore_forcewake_put__locked(uncore, fw_domains);
+ spin_unlock_irq(&uncore->lock);
+ }
+
+ return ret;
+}
+
+static int
+query_cs_cycles(struct drm_i915_private *i915,
+ struct drm_i915_query_item *query_item)
+{
+ struct drm_i915_query_cs_cycles __user *query_ptr;
+ struct drm_i915_query_cs_cycles query;
+ struct intel_engine_cs *engine;
+ __ktime_func_t cpu_clock;
+ int ret;
+
+ if (GRAPHICS_VER(i915) < 6)
+ return -ENODEV;
+
+ query_ptr = u64_to_user_ptr(query_item->data_ptr);
+ ret = copy_query_item(&query, sizeof(query), sizeof(query), query_item);
+ if (ret != 0)
+ return ret;
+
+ if (query.flags)
+ return -EINVAL;
+
+ if (query.rsvd)
+ return -EINVAL;
+
+ cpu_clock = __clock_id_to_func(query.clockid);
+ if (!cpu_clock)
+ return -EINVAL;
+
+ engine = intel_engine_lookup_user(i915,
+ query.engine.engine_class,
+ query.engine.engine_instance);
+ if (!engine)
+ return -EINVAL;
+
+ if (GRAPHICS_VER(i915) == 6 &&
+ query.engine.engine_class != I915_ENGINE_CLASS_RENDER)
+ return -ENODEV;
+
+ query.cs_frequency = engine->gt->clock_frequency;
+ ret = __query_cs_cycles(engine,
+ &query.cs_cycles,
+ &query.cpu_timestamp,
+ &query.cpu_delta,
+ cpu_clock);
+ if (ret)
+ return ret;
+
+ if (put_user(query.cs_frequency, &query_ptr->cs_frequency))
+ return -EFAULT;
+
+ if (put_user(query.cpu_timestamp, &query_ptr->cpu_timestamp))
+ return -EFAULT;
+
+ if (put_user(query.cpu_delta, &query_ptr->cpu_delta))
+ return -EFAULT;
+
+ if (put_user(query.cs_cycles, &query_ptr->cs_cycles))
+ return -EFAULT;
+
+ return sizeof(query);
+}
+
static int
query_engine_info(struct drm_i915_private *i915,
struct drm_i915_query_item *query_item)
@@ -424,6 +571,7 @@ static int (* const i915_query_funcs[])(struct drm_i915_private *dev_priv,
query_topology_info,
query_engine_info,
query_perf_config,
+ query_cs_cycles,
};
int i915_query_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 6a34243a7646..0b4c27092d41 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -2230,6 +2230,10 @@ struct drm_i915_query_item {
#define DRM_I915_QUERY_TOPOLOGY_INFO 1
#define DRM_I915_QUERY_ENGINE_INFO 2
#define DRM_I915_QUERY_PERF_CONFIG 3
+ /**
+ * Query Command Streamer timestamp register.
+ */
+#define DRM_I915_QUERY_CS_CYCLES 4
/* Must be kept compact -- no holes and well documented */
/**
@@ -2397,6 +2401,54 @@ struct drm_i915_engine_info {
__u64 rsvd1[4];
};
+/**
+ * struct drm_i915_query_cs_cycles
+ *
+ * The query returns the command streamer cycles and the frequency that can be
+ * used to calculate the command streamer timestamp. In addition the query
+ * returns a set of cpu timestamps that indicate when the command streamer cycle
+ * count was captured.
+ */
+struct drm_i915_query_cs_cycles {
+ /** Engine for which command streamer cycles is queried. */
+ struct i915_engine_class_instance engine;
+
+ /** Must be zero. */
+ __u32 flags;
+
+ /**
+ * Command streamer cycles as read from the command streamer
+ * register at 0x358 offset.
+ */
+ __u64 cs_cycles;
+
+ /** Frequency of the cs cycles in Hz. */
+ __u64 cs_frequency;
+
+ /**
+ * CPU timestamp in ns. The timestamp is captured before reading the
+ * cs_cycles register using the reference clockid set by the user.
+ */
+ __u64 cpu_timestamp;
+
+ /**
+ * Time delta in ns captured around reading the lower dword of the
+ * cs_cycles register.
+ */
+ __u64 cpu_delta;
+
+ /**
+ * Reference clock id for CPU timestamp. For definition, see
+ * clock_gettime(2) and perf_event_open(2). Supported clock ids are
+ * CLOCK_MONOTONIC, CLOCK_MONOTONIC_RAW, CLOCK_REALTIME, CLOCK_BOOTTIME,
+ * CLOCK_TAI.
+ */
+ __s32 clockid;
+
+ /** Must be zero. */
+ __u32 rsvd;
+};
+
/**
* struct drm_i915_query_engine_info
*
