sna: Use the existing configuration for initial modes

After checking for user overrides (preferred output modes, rotation and
placement), copy the current CRTC configuration from the kernel into the
desired modes. This should enable X to start without introducing any extra
flicker.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 155 insertions, 1 deletions

diff --git a/src/sna/sna_display.c b/src/sna/sna_display.c
index a9cec121..8c8d8444 100644
--- a/src/sna/sna_display.c
+++ b/src/sna/sna_display.c
@@ -2945,6 +2945,159 @@ static void set_size_range(struct sna *sna)
 	xf86CrtcSetSizeRange(sna->scrn, 320, 200, INT16_MAX, INT16_MAX);
 }
 
+static bool sna_probe_initial_configuration(struct sna *sna)
+{
+	ScrnInfoPtr scrn = sna->scrn;
+	xf86CrtcConfigPtr config = XF86_CRTC_CONFIG_PTR(scrn);
+	const int user_overrides[] = {
+		2, 3, 4, 5, 6, /* position */
+		11, /* rotate */
+		12, /* panning */
+	};
+	int width, height;
+	int i, j;
+
+	/* First scan through all outputs and look for user overrides */
+	for (i = 0; i < config->num_output; i++) {
+		xf86OutputPtr output = config->output[i];
+		DisplayModePtr mode;
+
+		for (j = 0; j < ARRAY_SIZE(user_overrides); j++) {
+			if (xf86GetOptValString(output->options, user_overrides[j])) {
+				DBG(("%s: user placement [%d] for %s\j",
+				     __FUNCTION__,
+				     user_overrides[j],
+				     output->name));
+				return false;
+			}
+		}
+
+		for (mode = output->probed_modes;
+		     mode && mode->next != output->probed_modes;
+		     mode = mode->next) {
+			if (mode->type & M_T_USERPREF) {
+				DBG(("%s: user mode for %s\n",
+				     __FUNCTION__,
+				     output->name));
+				return false;
+			}
+		}
+	}
+
+	/* Copy the existing modes on each CRTCs */
+	for (i = 0; i < config->num_crtc; i++) {
+		xf86CrtcPtr crtc = config->crtc[i];
+		struct sna_crtc *sna_crtc = to_sna_crtc(crtc);
+		struct drm_mode_crtc mode;
+		uint16_t *gamma;
+
+		crtc->enabled = FALSE;
+		crtc->desiredMode.status = MODE_NOMODE;
+
+		VG_CLEAR(mode);
+		mode.crtc_id = sna_crtc->id;
+		if (drmIoctl(sna->kgem.fd, DRM_IOCTL_MODE_GETCRTC, &mode))
+			continue;
+
+		if (!mode.mode_valid)
+			continue;
+
+		memset(&crtc->desiredMode, 0, sizeof(crtc->desiredMode));
+		mode_from_kmode(scrn, &mode.mode, &crtc->desiredMode);
+		crtc->desiredRotation = 0;
+		crtc->desiredX = mode.x;
+		crtc->desiredY = mode.y;
+
+		memset(&crtc->panningTotalArea, 0, sizeof(BoxRec));
+		memset(&crtc->panningTrackingArea, 0, sizeof(BoxRec));
+		memset(crtc->panningBorder, 0, 4 * sizeof(INT16));
+
+		gamma = malloc(3 * mode.gamma_size * sizeof(uint16_t));
+		if (gamma) {
+			struct drm_mode_crtc_lut lut;
+
+			lut.crtc_id = mode.crtc_id;
+			lut.gamma_size = mode.gamma_size;
+			lut.red = (uintptr_t)(gamma);
+			lut.green = (uintptr_t)(gamma + mode.gamma_size);
+			lut.blue = (uintptr_t)(gamma + 2 * mode.gamma_size);
+			if (drmIoctl(sna->kgem.fd, DRM_IOCTL_MODE_GETGAMMA, &lut) == 0) {
+				free(crtc->gamma_red);
+				crtc->gamma_size = mode.gamma_size;
+				crtc->gamma_red = gamma;
+				crtc->gamma_green = gamma + mode.gamma_size;
+				crtc->gamma_blue = gamma + 2*mode.gamma_size;
+			}
+		}
+	}
+
+	/* Reconstruct outputs pointing to active CRTC */
+	for (i = 0; i < config->num_output; i++) {
+		xf86OutputPtr output = config->output[i];
+		struct sna_output *sna_output = to_sna_output(output);
+		struct drm_mode_get_encoder enc;
+		Bool disable;
+
+		output->crtc = NULL;
+		if (xf86GetOptValBool(output->options,
+				      8 /* OPTION_DISABLE */,
+				      &disable) && disable)
+			continue;
+
+		VG_CLEAR(enc);
+		enc.encoder_id = sna->mode.kmode->encoders[sna_output->encoder_idx];
+		if (drmIoctl(sna->kgem.fd, DRM_IOCTL_MODE_GETENCODER, &enc))
+			continue;
+
+		if (enc.crtc_id == 0)
+			continue;
+
+		for (j = 0; j < config->num_crtc; j++) {
+			xf86CrtcPtr crtc = config->crtc[j];
+			if (to_sna_crtc(crtc)->id == enc.crtc_id) {
+				if (crtc->desiredMode.status == MODE_OK) {
+					xf86DrvMsg(scrn->scrnIndex, X_INFO,
+						   "Output %s using initial mode %s on pipe %d\n",
+						   output->name,
+						   crtc->desiredMode.name,
+						   to_sna_crtc(crtc)->pipe);
+
+					output->crtc = crtc;
+					crtc->enabled = TRUE;
+				}
+				break;
+			}
+		}
+	}
+
+	width = height = 0;
+	for (i = 0; i < config->num_crtc; i++) {
+		xf86CrtcPtr crtc = config->crtc[i];
+		int w, h;
+
+		if (!crtc->enabled)
+			continue;
+
+		w = crtc->desiredX + crtc->desiredMode.HDisplay;
+		if (w > width)
+			width = w;
+		h = crtc->desiredY + crtc->desiredMode.VDisplay;
+		if (h > height)
+			height = h;
+	}
+
+	scrn->display->frameX0 = 0;
+	scrn->display->frameY0 = 0;
+	scrn->display->virtualX = width;
+	scrn->display->virtualY = height;
+
+	scrn->virtualX = width;
+	scrn->virtualY = height;
+
+	xf86SetScrnInfoModes(sna->scrn);
+	return true;
+}
+
 bool sna_mode_pre_init(ScrnInfoPtr scrn, struct sna *sna)
 {
 	struct sna_mode *mode = &sna->mode;
@@ -2975,7 +3128,8 @@ bool sna_mode_pre_init(ScrnInfoPtr scrn, struct sna *sna)
 
 	set_size_range(sna);
 
-	xf86InitialConfiguration(scrn, TRUE);
+	if (!sna_probe_initial_configuration(sna))
+		xf86InitialConfiguration(scrn, TRUE);
 	return scrn->modes != NULL;
 }