[PATCH i-g-t v2 11/66] lib/xe_eudebug: Add support for dynamic debugger sysfs toggle

[Christoph Manszewski <christoph.manszewski@intel.com>]

The debugger now uses a dedicated sysfs entry:

/sys/class/drm/card<N>/device/enable_eudebug

to toggle the debugger on/off. This change adds helper functons for
toggling the debugger.

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Christoph Manszewski <christoph.manszewski@intel.com>
Cc: Dominik Grzegorzek <dominik.grzegorzek@intel.com>
---
 lib/xe/xe_eudebug.c | 88 +++++++++++++++++++++++++++++++++++++++++++++
 lib/xe/xe_eudebug.h |  3 ++
 2 files changed, 91 insertions(+)

diff --git a/lib/xe/xe_eudebug.c b/lib/xe/xe_eudebug.c
index af7cc5fc4..36eef25c7 100644
--- a/lib/xe/xe_eudebug.c
+++ b/lib/xe/xe_eudebug.c
@@ -7,10 +7,12 @@
 #include <poll.h>
 #include <signal.h>
 #include <sys/select.h>
+#include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/wait.h>
 
 #include "igt.h"
+#include "igt_sysfs.h"
 #include "intel_pat.h"
 #include "xe_eudebug.h"
 #include "xe_ioctl.h"
@@ -1040,6 +1042,24 @@ static void *debugger_worker_loop(void *data)
 	return NULL;
 }
 
+/**
+ * xe_eudebug_debugger_available:
+ * @fd: Xe file descriptor
+ *
+ * Returns: true it debugger connection is available, false otherwise.
+ */
+bool xe_eudebug_debugger_available(int fd)
+{
+	struct drm_xe_eudebug_connect param = { .pid = getpid() };
+	int debugfd;
+
+	debugfd = igt_ioctl(fd, DRM_IOCTL_XE_EUDEBUG_CONNECT, &param);
+	if (debugfd >= 0)
+		close(debugfd);
+
+	return debugfd >= 0;
+}
+
 /**
  * xe_eudebug_debugger_create:
  * @master_fd: xe client used to open the debugger connection
@@ -1563,6 +1583,74 @@ static void metadata_event(struct xe_eudebug_client *c, uint32_t flags,
 	xe_eudebug_event_log_write(c->log, (void *)&em);
 }
 
+static int enable_getset(int fd, bool *old, bool *new)
+{
+	static const char * const fname = "enable_eudebug";
+	int ret = 0;
+
+	int sysfs, device_fd;
+	bool val_before;
+	struct stat st;
+
+	igt_assert(new || old);
+
+	igt_assert_eq(fstat(fd, &st), 0);
+	sysfs = igt_sysfs_open(fd);
+	if (sysfs < 0)
+		return -1;
+
+	device_fd = openat(sysfs, "device", O_DIRECTORY | O_RDONLY);
+	close(sysfs);
+	if (device_fd < 0)
+		return -1;
+
+	if (!__igt_sysfs_get_boolean(device_fd, fname, &val_before)) {
+		ret = -1;
+		goto out;
+	}
+
+	igt_debug("enable_eudebug before: %d\n", val_before);
+
+	if (old)
+		*old = val_before;
+
+	ret = 0;
+	if (new) {
+		if (__igt_sysfs_set_boolean(device_fd, fname, *new))
+			igt_assert_eq(igt_sysfs_get_boolean(device_fd, fname), *new);
+		else
+			ret = -1;
+	}
+
+out:
+	close(device_fd);
+	return ret;
+}
+
+/**
+ * xe_eudebug_enable
+ * @fd: xe client
+ * @enable: state toggle - true to enable, false to disable
+ *
+ * Enables/disables eudebug capability by writing to
+ * '/sys/class/drm/card<N>/device/enable_eudebug' sysfs entry.
+ *
+ * Returns: previous toggle value, i.e. true when eudebugging was enabled,
+ * false when eudebugging was disabled.
+ */
+bool xe_eudebug_enable(int fd, bool enable)
+{
+	bool old = false;
+	int ret = enable_getset(fd, &old, &enable);
+
+	if (ret) {
+		igt_skip_on(enable);
+		old = false;
+	}
+
+	return old;
+}
+
 /* Eu debugger wrappers around resource creating xe ioctls. */
 
 /**
diff --git a/lib/xe/xe_eudebug.h b/lib/xe/xe_eudebug.h
index ec75634f5..1343cb25c 100644
--- a/lib/xe/xe_eudebug.h
+++ b/lib/xe/xe_eudebug.h
@@ -123,6 +123,7 @@ void xe_eudebug_event_log_compare(struct xe_eudebug_event_log *c, struct xe_eude
 void xe_eudebug_event_log_write(struct xe_eudebug_event_log *l, struct drm_xe_eudebug_event *e);
 void xe_eudebug_event_log_match_opposite(struct xe_eudebug_event_log *l, uint32_t filter);
 
+bool xe_eudebug_debugger_available(int fd);
 struct xe_eudebug_debugger *
 xe_eudebug_debugger_create(int xe, uint64_t flags, void *data);
 void xe_eudebug_debugger_destroy(struct xe_eudebug_debugger *d);
@@ -146,6 +147,8 @@ void xe_eudebug_client_wait_stage(struct xe_eudebug_client *c, uint64_t stage);
 uint64_t xe_eudebug_client_get_seqno(struct xe_eudebug_client *c);
 void xe_eudebug_client_set_data(struct xe_eudebug_client *c, void *ptr);
 
+bool xe_eudebug_enable(int fd, bool enable);
+
 int xe_eudebug_client_open_driver(struct xe_eudebug_client *c);
 void xe_eudebug_client_close_driver(struct xe_eudebug_client *c, int fd);
 uint32_t xe_eudebug_client_vm_create(struct xe_eudebug_client *c, int fd,
-- 
2.34.1