drm/tegra: dc: Implement hardware VBLANK counter
The display controller on Tegra can use syncpoints to count VBLANK
events. syncpoints are 32-bit unsigned integers, so well suited as
VBLANK counters.
Signed-off-by: Thierry Reding <treding@nvidia.com>
diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c
index 8746a9c..9e32946 100644
--- a/drivers/gpu/drm/tegra/dc.c
+++ b/drivers/gpu/drm/tegra/dc.c
@@ -906,6 +906,15 @@
return 0;
}
+u32 tegra_dc_get_vblank_counter(struct tegra_dc *dc)
+{
+ if (dc->syncpt)
+ return host1x_syncpt_read(dc->syncpt);
+
+ /* fallback to software emulated VBLANK counter */
+ return drm_crtc_vblank_count(&dc->base);
+}
+
void tegra_dc_enable_vblank(struct tegra_dc *dc)
{
unsigned long value, flags;
@@ -1632,7 +1641,6 @@
struct tegra_drm *tegra = drm->dev_private;
struct drm_plane *primary = NULL;
struct drm_plane *cursor = NULL;
- unsigned int syncpt;
u32 value;
int err;
@@ -1701,13 +1709,15 @@
}
/* initialize display controller */
- if (dc->pipe)
- syncpt = SYNCPT_VBLANK1;
- else
- syncpt = SYNCPT_VBLANK0;
+ if (dc->syncpt) {
+ u32 syncpt = host1x_syncpt_id(dc->syncpt);
- tegra_dc_writel(dc, 0x00000100, DC_CMD_GENERAL_INCR_SYNCPT_CNTRL);
- tegra_dc_writel(dc, 0x100 | syncpt, DC_CMD_CONT_SYNCPT_VSYNC);
+ value = SYNCPT_CNTRL_NO_STALL;
+ tegra_dc_writel(dc, value, DC_CMD_GENERAL_INCR_SYNCPT_CNTRL);
+
+ value = SYNCPT_VSYNC_ENABLE | syncpt;
+ tegra_dc_writel(dc, value, DC_CMD_CONT_SYNCPT_VSYNC);
+ }
value = WIN_A_UF_INT | WIN_B_UF_INT | WIN_C_UF_INT | WIN_A_OF_INT;
tegra_dc_writel(dc, value, DC_CMD_INT_TYPE);
@@ -1875,6 +1885,7 @@
static int tegra_dc_probe(struct platform_device *pdev)
{
+ unsigned long flags = HOST1X_SYNCPT_CLIENT_MANAGED;
const struct of_device_id *id;
struct resource *regs;
struct tegra_dc *dc;
@@ -1966,6 +1977,10 @@
return err;
}
+ dc->syncpt = host1x_syncpt_request(&pdev->dev, flags);
+ if (!dc->syncpt)
+ dev_warn(&pdev->dev, "failed to allocate syncpoint\n");
+
platform_set_drvdata(pdev, dc);
return 0;
@@ -1976,6 +1991,8 @@
struct tegra_dc *dc = platform_get_drvdata(pdev);
int err;
+ host1x_syncpt_free(dc->syncpt);
+
err = host1x_client_unregister(&dc->client);
if (err < 0) {
dev_err(&pdev->dev, "failed to unregister host1x client: %d\n",