radv: Add startup debug option.

This adds a RADV_DEBUG=startup option to dump more info about
instance creation and device enumeration.

A common question end users have is why the direver is not loading
for them, and this has two common reasons:
1) They did not install the driver.
2) AMDGPU is not used for the card in the kernel.

This adds some info messages so we can easily get a some useful
output from end users.

Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>

src/amd/vulkan/radv_debug.h

@@ -47,6 +47,7 @@ enum {
 	RADV_DEBUG_NO_OUT_OF_ORDER   = 0x20000,
 	RADV_DEBUG_INFO              = 0x40000,
 	RADV_DEBUG_ERRORS            = 0x80000,
+	RADV_DEBUG_STARTUP           = 0x100000,
 };
 
 enum {

src/amd/vulkan/radv_device.c

@@ -227,12 +227,20 @@ radv_physical_device_init(struct radv_physical_device *device,
 	int fd;
 
 	fd = open(path, O_RDWR | O_CLOEXEC);
-	if (fd < 0)
+	if (fd < 0) {
+		if (instance->debug_flags & RADV_DEBUG_STARTUP)
+			radv_logi("Could not open device '%s'", path);
+
 		return vk_error(instance, VK_ERROR_INCOMPATIBLE_DRIVER);
+	}
 
 	version = drmGetVersion(fd);
 	if (!version) {
 		close(fd);
+
+		if (instance->debug_flags & RADV_DEBUG_STARTUP)
+			radv_logi("Could not get the kernel driver version for device '%s'", path);
+
 		return vk_errorf(instance, VK_ERROR_INCOMPATIBLE_DRIVER,
 				 "failed to get version %s: %m", path);
 	}
@@ -240,10 +248,17 @@ radv_physical_device_init(struct radv_physical_device *device,
 	if (strcmp(version->name, "amdgpu")) {
 		drmFreeVersion(version);
 		close(fd);
+
+		if (instance->debug_flags & RADV_DEBUG_STARTUP)
+			radv_logi("Device '%s' is not using the amdgpu kernel driver.", path);
+
 		return VK_ERROR_INCOMPATIBLE_DRIVER;
 	}
 	drmFreeVersion(version);
 
+	if (instance->debug_flags & RADV_DEBUG_STARTUP)
+			radv_logi("Found compatible device '%s'.", path);
+
 	device->_loader_data.loaderMagic = ICD_LOADER_MAGIC;
 	device->instance = instance;
 	assert(strlen(path) < ARRAY_SIZE(device->path));
@@ -252,7 +267,7 @@ radv_physical_device_init(struct radv_physical_device *device,
 	device->ws = radv_amdgpu_winsys_create(fd, instance->debug_flags,
 					       instance->perftest_flags);
 	if (!device->ws) {
-		result = VK_ERROR_INCOMPATIBLE_DRIVER;
+		result = vk_error(instance, VK_ERROR_INCOMPATIBLE_DRIVER);
 		goto fail;
 	}
 
@@ -323,6 +338,7 @@ radv_physical_device_init(struct radv_physical_device *device,
 	result = radv_init_wsi(device);
 	if (result != VK_SUCCESS) {
 		device->ws->destroy(device->ws);
+		vk_error(instance, result);
 		goto fail;
 	}
 
@@ -393,6 +409,7 @@ static const struct debug_control radv_debug_options[] = {
 	{"nooutoforder", RADV_DEBUG_NO_OUT_OF_ORDER},
 	{"info", RADV_DEBUG_INFO},
 	{"errors", RADV_DEBUG_ERRORS},
+	{"startup", RADV_DEBUG_STARTUP},
 	{NULL, 0}
 };
 
@@ -488,6 +505,10 @@ VkResult radv_CreateInstance(
 	instance->perftest_flags = parse_debug_string(getenv("RADV_PERFTEST"),
 						   radv_perftest_options);
 
+
+	if (instance->debug_flags & RADV_DEBUG_STARTUP)
+		radv_logi("Created an instance");
+
 	for (uint32_t i = 0; i < pCreateInfo->enabledExtensionCount; i++) {
 		const char *ext_name = pCreateInfo->ppEnabledExtensionNames[i];
 		int index = radv_get_instance_extension_index(ext_name);
@@ -550,6 +571,10 @@ radv_enumerate_devices(struct radv_instance *instance)
 	instance->physicalDeviceCount = 0;
 
 	max_devices = drmGetDevices2(0, devices, ARRAY_SIZE(devices));
+
+	if (instance->debug_flags & RADV_DEBUG_STARTUP)
+		radv_logi("Found %d drm nodes", max_devices);
+
 	if (max_devices < 1)
 		return vk_error(instance, VK_ERROR_INCOMPATIBLE_DRIVER);
 

src/amd/vulkan/radv_private.h

@@ -228,6 +228,8 @@ void __radv_finishme(const char *file, int line, const char *format, ...)
 	radv_printflike(3, 4);
 void radv_loge(const char *format, ...) radv_printflike(1, 2);
 void radv_loge_v(const char *format, va_list va);
+void radv_logi(const char *format, ...) radv_printflike(1, 2);
+void radv_logi_v(const char *format, va_list va);
 
 /**
  * Print a FINISHME message, including its source location.

src/amd/vulkan/radv_util.c

@@ -54,6 +54,26 @@ radv_loge_v(const char *format, va_list va)
 	fprintf(stderr, "\n");
 }
 
+/** Log an error message.  */
+void radv_printflike(1, 2)
+	radv_logi(const char *format, ...)
+{
+	va_list va;
+
+	va_start(va, format);
+	radv_logi_v(format, va);
+	va_end(va);
+}
+
+/** \see radv_logi() */
+void
+radv_logi_v(const char *format, va_list va)
+{
+	fprintf(stderr, "radv: info: ");
+	vfprintf(stderr, format, va);
+	fprintf(stderr, "\n");
+}
+
 void radv_printflike(3, 4)
 	__radv_finishme(const char *file, int line, const char *format, ...)
 {