vulkan: Add VK_EXT_calibrated_timestamps extension (radv and anv) [v5]

Offers three clocks, device, clock monotonic and clock monotonic
raw. Could use some kernel support to reduce the deviation between
clock values.

v2:
	Ensure deviation is at least as big as the GPU time interval.

v3:
	Set device->lost when returning DEVICE_LOST.
	Use MAX2 and DIV_ROUND_UP instead of open coding these.
	Delete spurious TIMESTAMP in radv version.

	Suggested-by: Jason Ekstrand <[email protected]>
	Suggested-by: Lionel Landwerlin <[email protected]>

v4:
	Add anv_gem_reg_read to anv_gem_stubs.c

	Suggested-by: Jason Ekstrand <[email protected]>

v5:
	Adjust maxDeviation computation to max(sampled_clock_period) +
	sample_interval.

	Suggested-by: Bas Nieuwenhuizen <[email protected]>
	Suggested-by: Jason Ekstrand <[email protected]>

Signed-off-by: Keith Packard <[email protected]>
Reviewed-by: Jason Ekstrand <[email protected]>
Reviewed-by: Bas Nieuwenhuizen <[email protected]>

2 files changed, 120 insertions, 0 deletions

diff --git a/src/amd/vulkan/radv_device.c b/src/amd/vulkan/radv_device.c
index 85e5d9014d8..6eb37472992 100644
--- a/src/amd/vulkan/radv_device.c
+++ b/src/amd/vulkan/radv_device.c
@@ -4957,3 +4957,122 @@ radv_GetDeviceGroupPeerMemoryFeatures(
 	                       VK_PEER_MEMORY_FEATURE_GENERIC_SRC_BIT |
 	                       VK_PEER_MEMORY_FEATURE_GENERIC_DST_BIT;
 }
+
+static const VkTimeDomainEXT radv_time_domains[] = {
+	VK_TIME_DOMAIN_DEVICE_EXT,
+	VK_TIME_DOMAIN_CLOCK_MONOTONIC_EXT,
+	VK_TIME_DOMAIN_CLOCK_MONOTONIC_RAW_EXT,
+};
+
+VkResult radv_GetPhysicalDeviceCalibrateableTimeDomainsEXT(
+	VkPhysicalDevice                             physicalDevice,
+	uint32_t                                     *pTimeDomainCount,
+	VkTimeDomainEXT                              *pTimeDomains)
+{
+	int d;
+	VK_OUTARRAY_MAKE(out, pTimeDomains, pTimeDomainCount);
+
+	for (d = 0; d < ARRAY_SIZE(radv_time_domains); d++) {
+		vk_outarray_append(&out, i) {
+			*i = radv_time_domains[d];
+		}
+	}
+
+	return vk_outarray_status(&out);
+}
+
+static uint64_t
+radv_clock_gettime(clockid_t clock_id)
+{
+	struct timespec current;
+	int ret;
+
+	ret = clock_gettime(clock_id, &current);
+	if (ret < 0 && clock_id == CLOCK_MONOTONIC_RAW)
+		ret = clock_gettime(CLOCK_MONOTONIC, &current);
+	if (ret < 0)
+		return 0;
+
+	return (uint64_t) current.tv_sec * 1000000000ULL + current.tv_nsec;
+}
+
+VkResult radv_GetCalibratedTimestampsEXT(
+	VkDevice                                     _device,
+	uint32_t                                     timestampCount,
+	const VkCalibratedTimestampInfoEXT           *pTimestampInfos,
+	uint64_t                                     *pTimestamps,
+	uint64_t                                     *pMaxDeviation)
+{
+	RADV_FROM_HANDLE(radv_device, device, _device);
+	uint32_t clock_crystal_freq = device->physical_device->rad_info.clock_crystal_freq;
+	int d;
+	uint64_t begin, end;
+        uint64_t max_clock_period = 0;
+
+	begin = radv_clock_gettime(CLOCK_MONOTONIC_RAW);
+
+	for (d = 0; d < timestampCount; d++) {
+		switch (pTimestampInfos[d].timeDomain) {
+		case VK_TIME_DOMAIN_DEVICE_EXT:
+			pTimestamps[d] = device->ws->query_value(device->ws,
+								 RADEON_TIMESTAMP);
+                        uint64_t device_period = DIV_ROUND_UP(1000000, clock_crystal_freq);
+                        max_clock_period = MAX2(max_clock_period, device_period);
+			break;
+		case VK_TIME_DOMAIN_CLOCK_MONOTONIC_EXT:
+			pTimestamps[d] = radv_clock_gettime(CLOCK_MONOTONIC);
+                        max_clock_period = MAX2(max_clock_period, 1);
+			break;
+
+		case VK_TIME_DOMAIN_CLOCK_MONOTONIC_RAW_EXT:
+			pTimestamps[d] = begin;
+			break;
+		default:
+			pTimestamps[d] = 0;
+			break;
+		}
+	}
+
+	end = radv_clock_gettime(CLOCK_MONOTONIC_RAW);
+
+        /*
+         * The maximum deviation is the sum of the interval over which we
+         * perform the sampling and the maximum period of any sampled
+         * clock. That's because the maximum skew between any two sampled
+         * clock edges is when the sampled clock with the largest period is
+         * sampled at the end of that period but right at the beginning of the
+         * sampling interval and some other clock is sampled right at the
+         * begining of its sampling period and right at the end of the
+         * sampling interval. Let's assume the GPU has the longest clock
+         * period and that the application is sampling GPU and monotonic:
+         *
+         *                               s                 e
+         *			 w x y z 0 1 2 3 4 5 6 7 8 9 a b c d e f
+         *	Raw              -_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-
+         *
+         *                               g
+         *		  0         1         2         3
+         *	GPU       -----_____-----_____-----_____-----_____
+         *
+         *                                                m
+         *					    x y z 0 1 2 3 4 5 6 7 8 9 a b c
+         *	Monotonic                           -_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-
+         *
+         *	Interval                     <----------------->
+         *	Deviation           <-------------------------->
+         *
+         *		s  = read(raw)       2
+         *		g  = read(GPU)       1
+         *		m  = read(monotonic) 2
+         *		e  = read(raw)       b
+         *
+         * We round the sample interval up by one tick to cover sampling error
+         * in the interval clock
+         */
+
+        uint64_t sample_interval = end - begin + 1;
+
+        *pMaxDeviation = sample_interval + max_clock_period;
+
+	return VK_SUCCESS;
+}
diff --git a/src/amd/vulkan/radv_extensions.py b/src/amd/vulkan/radv_extensions.py
index 5dcedae1c63..4c81d3f0068 100644
--- a/src/amd/vulkan/radv_extensions.py
+++ b/src/amd/vulkan/radv_extensions.py
@@ -92,6 +92,7 @@ EXTENSIONS = [
     Extension('VK_KHR_display',                          23, 'VK_USE_PLATFORM_DISPLAY_KHR'),
     Extension('VK_EXT_direct_mode_display',               1, 'VK_USE_PLATFORM_DISPLAY_KHR'),
     Extension('VK_EXT_acquire_xlib_display',              1, 'VK_USE_PLATFORM_XLIB_XRANDR_EXT'),
+    Extension('VK_EXT_calibrated_timestamps',             1, True),
     Extension('VK_EXT_conditional_rendering',             1, True),
     Extension('VK_EXT_conservative_rasterization',        1, 'device->rad_info.chip_class >= GFX9'),
     Extension('VK_EXT_display_surface_counter',           1, 'VK_USE_PLATFORM_DISPLAY_KHR'),