drm/xe/oa: Allow oa_exponent value of 0

OA exponent value of 0 is a valid value for periodic reports. Allow user
to pass 0 for the OA sampling interval since it gets converted to 2 gt
clock ticks.

v2: Update the check in xe_oa_stream_init as well (Ashutosh)
v3: Fix mi-rpc failure by setting default exponent to -1 (CI)
v4: Add the Fixes tag

Fixes: b6fd51c ("drm/xe/oa/uapi: Define and parse OA stream properties")
Signed-off-by: Umesh Nerlige Ramappa <[email protected]>
Reviewed-by: Ashutosh Dixit <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
(cherry picked from commit 30341f0)
Signed-off-by: Rodrigo Vivi <[email protected]>

Author: unerlige

drivers/gpu/drm/xe/xe_oa.c

@@ -1689,7 +1689,7 @@ static int xe_oa_stream_init(struct xe_oa_stream *stream,
 	stream->oa_buffer.format = &stream->oa->oa_formats[param->oa_format];
 
 	stream->sample = param->sample;
-	stream->periodic = param->period_exponent > 0;
+	stream->periodic = param->period_exponent >= 0;
 	stream->period_exponent = param->period_exponent;
 	stream->no_preempt = param->no_preempt;
 	stream->wait_num_reports = param->wait_num_reports;
@@ -1970,6 +1970,7 @@ int xe_oa_stream_open_ioctl(struct drm_device *dev, u64 data, struct drm_file *f
 	}
 
 	param.xef = xef;
+	param.period_exponent = -1;
 	ret = xe_oa_user_extensions(oa, XE_OA_USER_EXTN_FROM_OPEN, data, 0, &param);
 	if (ret)
 		return ret;
@@ -2024,7 +2025,7 @@ int xe_oa_stream_open_ioctl(struct drm_device *dev, u64 data, struct drm_file *f
 		goto err_exec_q;
 	}
 
-	if (param.period_exponent > 0) {
+	if (param.period_exponent >= 0) {
 		u64 oa_period, oa_freq_hz;
 
 		/* Requesting samples from OAG buffer is a privileged operation */