drm/tegra: Implement page-flipping support

All the necessary support bits like .mode_set_base() and VBLANK are now
available, so page-flipping case easily be implemented on top.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c
index 5f55a25424a77bcdaabf2eb567f271c531b89b60..c5d825fd25fe9dd678c5f52f2bac8b02772b13b9 100644 (file)
--- a/drivers/gpu/drm/tegra/dc.c
+++ b/drivers/gpu/drm/tegra/dc.c
@@ -183,7 +183,72 @@ void tegra_dc_disable_vblank(struct tegra_dc *dc)
        spin_unlock_irqrestore(&dc->lock, flags);
 }
 
+static void tegra_dc_finish_page_flip(struct tegra_dc *dc)
+{
+       struct drm_device *drm = dc->base.dev;
+       struct drm_crtc *crtc = &dc->base;
+       struct drm_gem_cma_object *gem;
+       unsigned long flags, base;
+
+       if (!dc->event)
+               return;
+
+       gem = drm_fb_cma_get_gem_obj(crtc->fb, 0);
+
+       /* check if new start address has been latched */
+       tegra_dc_writel(dc, READ_MUX, DC_CMD_STATE_ACCESS);
+       base = tegra_dc_readl(dc, DC_WINBUF_START_ADDR);
+       tegra_dc_writel(dc, 0, DC_CMD_STATE_ACCESS);
+
+       if (base == gem->paddr + crtc->fb->offsets[0]) {
+               spin_lock_irqsave(&drm->event_lock, flags);
+               drm_send_vblank_event(drm, dc->pipe, dc->event);
+               drm_vblank_put(drm, dc->pipe);
+               dc->event = NULL;
+               spin_unlock_irqrestore(&drm->event_lock, flags);
+       }
+}
+
+void tegra_dc_cancel_page_flip(struct drm_crtc *crtc, struct drm_file *file)
+{
+       struct tegra_dc *dc = to_tegra_dc(crtc);
+       struct drm_device *drm = crtc->dev;
+       unsigned long flags;
+
+       spin_lock_irqsave(&drm->event_lock, flags);
+
+       if (dc->event && dc->event->base.file_priv == file) {
+               dc->event->base.destroy(&dc->event->base);
+               drm_vblank_put(drm, dc->pipe);
+               dc->event = NULL;
+       }
+
+       spin_unlock_irqrestore(&drm->event_lock, flags);
+}
+
+static int tegra_dc_page_flip(struct drm_crtc *crtc, struct drm_framebuffer *fb,
+                             struct drm_pending_vblank_event *event)
+{
+       struct tegra_dc *dc = to_tegra_dc(crtc);
+       struct drm_device *drm = crtc->dev;
+
+       if (dc->event)
+               return -EBUSY;
+
+       if (event) {
+               event->pipe = dc->pipe;
+               dc->event = event;
+               drm_vblank_get(drm, dc->pipe);
+       }
+
+       tegra_dc_set_base(dc, 0, 0, fb);
+       crtc->fb = fb;
+
+       return 0;
+}
+
 static const struct drm_crtc_funcs tegra_crtc_funcs = {
+       .page_flip = tegra_dc_page_flip,
        .set_config = drm_crtc_helper_set_config,
        .destroy = drm_crtc_cleanup,
 };
@@ -665,6 +730,7 @@ static irqreturn_t tegra_dc_irq(int irq, void *data)
                dev_dbg(dc->dev, "%s(): vertical blank\n", __func__);
                */
                drm_handle_vblank(dc->base.dev, dc->pipe);
+               tegra_dc_finish_page_flip(dc);
        }
 
        if (status & (WIN_A_UF_INT | WIN_B_UF_INT | WIN_C_UF_INT)) {

diff --git a/drivers/gpu/drm/tegra/dc.h b/drivers/gpu/drm/tegra/dc.h
index e2fa328861ca032f38e8446481cd11f608473692..79eaec9aac7752a27bddd06a4c08cf7f2292eac8 100644 (file)
--- a/drivers/gpu/drm/tegra/dc.h
+++ b/drivers/gpu/drm/tegra/dc.h
@@ -58,6 +58,8 @@
 #define DC_CMD_SIGNAL_RAISE3                   0x03e
 
 #define DC_CMD_STATE_ACCESS                    0x040
+#define READ_MUX  (1 << 0)
+#define WRITE_MUX (1 << 2)
 
 #define DC_CMD_STATE_CONTROL                   0x041
 #define GENERAL_ACT_REQ (1 <<  0)

diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
index 4e31dace52759f552a56940cf3b79ef63d77b49b..97485af6eaf934d0e53f46c9e0a28c2531c8e285 100644 (file)
--- a/drivers/gpu/drm/tegra/drm.c
+++ b/drivers/gpu/drm/tegra/drm.c
@@ -135,11 +135,20 @@ static void tegra_drm_disable_vblank(struct drm_device *drm, int pipe)
                tegra_dc_disable_vblank(dc);
 }
 
+static void tegra_drm_preclose(struct drm_device *drm, struct drm_file *file)
+{
+       struct drm_crtc *crtc;
+
+       list_for_each_entry(crtc, &drm->mode_config.crtc_list, head)
+               tegra_dc_cancel_page_flip(crtc, file);
+}
+
 struct drm_driver tegra_drm_driver = {
        .driver_features = DRIVER_BUS_PLATFORM | DRIVER_MODESET | DRIVER_GEM,
        .load = tegra_drm_load,
        .unload = tegra_drm_unload,
        .open = tegra_drm_open,
+       .preclose = tegra_drm_preclose,
        .lastclose = tegra_drm_lastclose,
 
        .get_vblank_counter = tegra_drm_get_vblank_counter,

diff --git a/drivers/gpu/drm/tegra/drm.h b/drivers/gpu/drm/tegra/drm.h
index 01f0aee12ad9ff879d6c1829e91fe86c86036e95..6dd75a2600eb2f59fa2c0f5006a8df95ea2cdbdb 100644 (file)
--- a/drivers/gpu/drm/tegra/drm.h
+++ b/drivers/gpu/drm/tegra/drm.h
@@ -84,6 +84,9 @@ struct tegra_dc {
        struct drm_info_list *debugfs_files;
        struct drm_minor *minor;
        struct dentry *debugfs;
+
+       /* page-flip handling */
+       struct drm_pending_vblank_event *event;
 };
 
 static inline struct tegra_dc *host1x_client_to_dc(struct host1x_client *client)
@@ -133,6 +136,8 @@ extern int tegra_dc_setup_window(struct tegra_dc *dc, unsigned int index,
                                 const struct tegra_dc_window *window);
 extern void tegra_dc_enable_vblank(struct tegra_dc *dc);
 extern void tegra_dc_disable_vblank(struct tegra_dc *dc);
+extern void tegra_dc_cancel_page_flip(struct drm_crtc *crtc,
+                                     struct drm_file *file);
 
 struct tegra_output_ops {
        int (*enable)(struct tegra_output *output);