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",
diff --git a/drivers/gpu/drm/tegra/dc.h b/drivers/gpu/drm/tegra/dc.h
index 705c93b..55792da 100644
--- a/drivers/gpu/drm/tegra/dc.h
+++ b/drivers/gpu/drm/tegra/dc.h
@@ -12,6 +12,8 @@
#define DC_CMD_GENERAL_INCR_SYNCPT 0x000
#define DC_CMD_GENERAL_INCR_SYNCPT_CNTRL 0x001
+#define SYNCPT_CNTRL_NO_STALL (1 << 8)
+#define SYNCPT_CNTRL_SOFT_RESET (1 << 0)
#define DC_CMD_GENERAL_INCR_SYNCPT_ERROR 0x002
#define DC_CMD_WIN_A_INCR_SYNCPT 0x008
#define DC_CMD_WIN_A_INCR_SYNCPT_CNTRL 0x009
@@ -23,6 +25,7 @@
#define DC_CMD_WIN_C_INCR_SYNCPT_CNTRL 0x019
#define DC_CMD_WIN_C_INCR_SYNCPT_ERROR 0x01a
#define DC_CMD_CONT_SYNCPT_VSYNC 0x028
+#define SYNCPT_VSYNC_ENABLE (1 << 8)
#define DC_CMD_DISPLAY_COMMAND_OPTION0 0x031
#define DC_CMD_DISPLAY_COMMAND 0x032
#define DISP_CTRL_MODE_STOP (0 << 5)
@@ -438,8 +441,4 @@
#define DC_WINBUF_BD_UFLOW_STATUS 0xdca
#define DC_WINBUF_CD_UFLOW_STATUS 0xfca
-/* synchronization points */
-#define SYNCPT_VBLANK0 26
-#define SYNCPT_VBLANK1 27
-
#endif /* TEGRA_DC_H */
diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
index 7ba7e28..8de17f9 100644
--- a/drivers/gpu/drm/tegra/drm.c
+++ b/drivers/gpu/drm/tegra/drm.c
@@ -172,6 +172,10 @@
*/
drm->irq_enabled = true;
+ /* syncpoints are used for full 32-bit hardware VBLANK counters */
+ drm->vblank_disable_immediate = true;
+ drm->max_vblank_count = 0xffffffff;
+
err = drm_vblank_init(drm, drm->mode_config.num_crtc);
if (err < 0)
goto device;
@@ -813,12 +817,12 @@
static u32 tegra_drm_get_vblank_counter(struct drm_device *drm, int pipe)
{
struct drm_crtc *crtc = tegra_crtc_from_pipe(drm, pipe);
+ struct tegra_dc *dc = to_tegra_dc(crtc);
if (!crtc)
return 0;
- /* TODO: implement real hardware counter using syncpoints */
- return drm_crtc_vblank_count(crtc);
+ return tegra_dc_get_vblank_counter(dc);
}
static int tegra_drm_enable_vblank(struct drm_device *drm, int pipe)
diff --git a/drivers/gpu/drm/tegra/drm.h b/drivers/gpu/drm/tegra/drm.h
index 8cb2dfe..ded04e3 100644
--- a/drivers/gpu/drm/tegra/drm.h
+++ b/drivers/gpu/drm/tegra/drm.h
@@ -106,6 +106,7 @@
struct tegra_dc {
struct host1x_client client;
+ struct host1x_syncpt *syncpt;
struct device *dev;
spinlock_t lock;
@@ -180,6 +181,7 @@
};
/* from dc.c */
+u32 tegra_dc_get_vblank_counter(struct tegra_dc *dc);
void tegra_dc_enable_vblank(struct tegra_dc *dc);
void tegra_dc_disable_vblank(struct tegra_dc *dc);
void tegra_dc_cancel_page_flip(struct drm_crtc *crtc, struct drm_file *file);