Commit 42e9ce05 authored by Thierry Reding's avatar Thierry Reding
Browse files

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: default avatarThierry Reding <treding@nvidia.com>
parent b4a20144

drivers/gpu/drm/tegra/dc.c

+24 −7
Original line number Diff line number Diff line
@@ -906,6 +906,15 @@ static int tegra_dc_add_planes(struct drm_device *drm, struct tegra_dc *dc) 
	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 @@ static int tegra_dc_init(struct host1x_client *client) 
	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 @@ static int tegra_dc_init(struct host1x_client *client) 
	}



	/* 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_parse_dt(struct tegra_dc *dc) 


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 @@ static int tegra_dc_probe(struct platform_device *pdev) 
		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 @@ static int tegra_dc_remove(struct platform_device *pdev) 
	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",

drivers/gpu/drm/tegra/dc.h

+3 −4
Original line number Diff line number Diff line
@@ -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 */

drivers/gpu/drm/tegra/drm.c

+6 −2
Original line number Diff line number Diff line
@@ -172,6 +172,10 @@ static int tegra_drm_load(struct drm_device *drm, unsigned long flags) 
	 */

	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 struct drm_crtc *tegra_crtc_from_pipe(struct drm_device *drm, 
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)

drivers/gpu/drm/tegra/drm.h

+2 −0
Original line number Diff line number Diff line
@@ -106,6 +106,7 @@ struct tegra_output; 


struct tegra_dc {

	struct host1x_client client;

	struct host1x_syncpt *syncpt;

	struct device *dev;

	spinlock_t lock;
@@ -180,6 +181,7 @@ struct tegra_dc_window { 
};



/* 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);