drm/rockchip: vop: export line flag function

VOP have integrated a hardware counter which indicate the exact display
line that vop is scanning. And if we're interested in a specific line,
we can set the line number to vop line_flag register, and then vop would
generate a line_flag interrupt for it.

For example eDP PSR function is interested in the vertical blanking
period, then driver could set the line number to zero.

This patch have exported a symbol that allow other driver to listen the
line flag event with given timeout limit:
-  rockchip_drm_wait_line_flag()

Signed-off-by: Yakir Yang <ykk@rock-chips.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.h b/drivers/gpu/drm/rockchip/rockchip_drm_drv.h
index ea39329..239b830 100644 (file)
--- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.h
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.h
@@ -70,4 +70,7 @@ int rockchip_drm_dma_attach_device(struct drm_device *drm_dev,
                                   struct device *dev);
 void rockchip_drm_dma_detach_device(struct drm_device *drm_dev,
                                    struct device *dev);
+int rockchip_drm_wait_line_flag(struct drm_crtc *crtc, unsigned int line_num,
+                               unsigned int mstimeout);
+
 #endif /* _ROCKCHIP_DRM_DRV_H_ */

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
index 42ce7d0..f5d8255 100644 (file)
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
@@ -119,6 +119,8 @@ struct vop {
        /* protected by dev->event_lock */
        struct drm_pending_vblank_event *event;
 
+       struct completion line_flag_completion;
+
        const struct vop_data *data;
 
        uint32_t *regsbak;
@@ -429,6 +431,71 @@ static void vop_dsp_hold_valid_irq_disable(struct vop *vop)
        spin_unlock_irqrestore(&vop->irq_lock, flags);
 }
 
+/*
+ * (1) each frame starts at the start of the Vsync pulse which is signaled by
+ *     the "FRAME_SYNC" interrupt.
+ * (2) the active data region of each frame ends at dsp_vact_end
+ * (3) we should program this same number (dsp_vact_end) into dsp_line_frag_num,
+ *      to get "LINE_FLAG" interrupt at the end of the active on screen data.
+ *
+ * VOP_INTR_CTRL0.dsp_line_frag_num = VOP_DSP_VACT_ST_END.dsp_vact_end
+ * Interrupts
+ * LINE_FLAG -------------------------------+
+ * FRAME_SYNC ----+                         |
+ *                |                         |
+ *                v                         v
+ *                | Vsync | Vbp |  Vactive  | Vfp |
+ *                        ^     ^           ^     ^
+ *                        |     |           |     |
+ *                        |     |           |     |
+ * dsp_vs_end ------------+     |           |     |   VOP_DSP_VTOTAL_VS_END
+ * dsp_vact_start --------------+           |     |   VOP_DSP_VACT_ST_END
+ * dsp_vact_end ----------------------------+     |   VOP_DSP_VACT_ST_END
+ * dsp_total -------------------------------------+   VOP_DSP_VTOTAL_VS_END
+ */
+static bool vop_line_flag_irq_is_enabled(struct vop *vop)
+{
+       uint32_t line_flag_irq;
+       unsigned long flags;
+
+       spin_lock_irqsave(&vop->irq_lock, flags);
+
+       line_flag_irq = VOP_INTR_GET_TYPE(vop, enable, LINE_FLAG_INTR);
+
+       spin_unlock_irqrestore(&vop->irq_lock, flags);
+
+       return !!line_flag_irq;
+}
+
+static void vop_line_flag_irq_enable(struct vop *vop, int line_num)
+{
+       unsigned long flags;
+
+       if (WARN_ON(!vop->is_enabled))
+               return;
+
+       spin_lock_irqsave(&vop->irq_lock, flags);
+
+       VOP_CTRL_SET(vop, line_flag_num[0], line_num);
+       VOP_INTR_SET_TYPE(vop, enable, LINE_FLAG_INTR, 1);
+
+       spin_unlock_irqrestore(&vop->irq_lock, flags);
+}
+
+static void vop_line_flag_irq_disable(struct vop *vop)
+{
+       unsigned long flags;
+
+       if (WARN_ON(!vop->is_enabled))
+               return;
+
+       spin_lock_irqsave(&vop->irq_lock, flags);
+
+       VOP_INTR_SET_TYPE(vop, enable, LINE_FLAG_INTR, 0);
+
+       spin_unlock_irqrestore(&vop->irq_lock, flags);
+}
+
 static void vop_enable(struct drm_crtc *crtc)
 {
        struct vop *vop = to_vop(crtc);
@@ -1151,6 +1218,12 @@ static irqreturn_t vop_isr(int irq, void *data)
                ret = IRQ_HANDLED;
        }
 
+       if (active_irqs & LINE_FLAG_INTR) {
+               complete(&vop->line_flag_completion);
+               active_irqs &= ~LINE_FLAG_INTR;
+               ret = IRQ_HANDLED;
+       }
+
        if (active_irqs & FS_INTR) {
                drm_crtc_handle_vblank(crtc);
                vop_handle_vblank(vop);
@@ -1249,6 +1322,7 @@ static int vop_create_crtc(struct vop *vop)
 
        init_completion(&vop->dsp_hold_completion);
        init_completion(&vop->wait_update_complete);
+       init_completion(&vop->line_flag_completion);
        crtc->port = port;
        rockchip_register_crtc_funcs(crtc, &private_crtc_funcs);
 
@@ -1405,6 +1479,49 @@ static void vop_win_init(struct vop *vop)
        }
 }
 
+/**
+ * rockchip_drm_wait_line_flag - acqiure the give line flag event
+ * @crtc: CRTC to enable line flag
+ * @line_num: interested line number
+ * @mstimeout: millisecond for timeout
+ *
+ * Driver would hold here until the interested line flag interrupt have
+ * happened or timeout to wait.
+ *
+ * Returns:
+ * Zero on success, negative errno on failure.
+ */
+int rockchip_drm_wait_line_flag(struct drm_crtc *crtc, unsigned int line_num,
+                               unsigned int mstimeout)
+{
+       struct vop *vop = to_vop(crtc);
+       unsigned long jiffies_left;
+
+       if (!crtc || !vop->is_enabled)
+               return -ENODEV;
+
+       if (line_num > crtc->mode.vtotal || mstimeout <= 0)
+               return -EINVAL;
+
+       if (vop_line_flag_irq_is_enabled(vop))
+               return -EBUSY;
+
+       reinit_completion(&vop->line_flag_completion);
+       vop_line_flag_irq_enable(vop, line_num);
+
+       jiffies_left = wait_for_completion_timeout(&vop->line_flag_completion,
+                                                  msecs_to_jiffies(mstimeout));
+       vop_line_flag_irq_disable(vop);
+
+       if (jiffies_left == 0) {
+               dev_err(vop->dev, "Timeout waiting for IRQ\n");
+               return -ETIMEDOUT;
+       }
+
+       return 0;
+}
+EXPORT_SYMBOL(rockchip_drm_wait_line_flag);
+
 static int vop_bind(struct device *dev, struct device *master, void *data)
 {
        struct platform_device *pdev = to_platform_device(dev);

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.h b/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
index ff4f52e..1dbc526 100644 (file)
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
@@ -61,6 +61,8 @@ struct vop_ctrl {
        struct vop_reg hpost_st_end;
        struct vop_reg vpost_st_end;
 
+       struct vop_reg line_flag_num[2];
+
        struct vop_reg cfg_done;
 };
 

diff --git a/drivers/gpu/drm/rockchip/rockchip_vop_reg.c b/drivers/gpu/drm/rockchip/rockchip_vop_reg.c
index a21b13b..e932b1b 100644 (file)
--- a/drivers/gpu/drm/rockchip/rockchip_vop_reg.c
+++ b/drivers/gpu/drm/rockchip/rockchip_vop_reg.c
@@ -123,6 +123,7 @@ static const struct vop_ctrl rk3036_ctrl_data = {
        .hact_st_end = VOP_REG(RK3036_DSP_HACT_ST_END, 0x1fff1fff, 0),
        .vtotal_pw = VOP_REG(RK3036_DSP_VTOTAL_VS_END, 0x1fff1fff, 0),
        .vact_st_end = VOP_REG(RK3036_DSP_VACT_ST_END, 0x1fff1fff, 0),
+       .line_flag_num[0] = VOP_REG(RK3036_INT_STATUS, 0xfff, 12),
        .cfg_done = VOP_REG(RK3036_REG_CFG_DONE, 0x1, 0),
 };
 
@@ -222,6 +223,7 @@ static const struct vop_ctrl rk3288_ctrl_data = {
        .vact_st_end = VOP_REG(RK3288_DSP_VACT_ST_END, 0x1fff1fff, 0),
        .hpost_st_end = VOP_REG(RK3288_POST_DSP_HACT_INFO, 0x1fff1fff, 0),
        .vpost_st_end = VOP_REG(RK3288_POST_DSP_VACT_INFO, 0x1fff1fff, 0),
+       .line_flag_num[0] = VOP_REG(RK3288_INTR_CTRL0, 0x1fff, 12),
        .cfg_done = VOP_REG(RK3288_REG_CFG_DONE, 0x1, 0),
 };
 
@@ -300,6 +302,8 @@ static const struct vop_ctrl rk3399_ctrl_data = {
        .vact_st_end = VOP_REG(RK3399_DSP_VACT_ST_END, 0x1fff1fff, 0),
        .hpost_st_end = VOP_REG(RK3399_POST_DSP_HACT_INFO, 0x1fff1fff, 0),
        .vpost_st_end = VOP_REG(RK3399_POST_DSP_VACT_INFO, 0x1fff1fff, 0),
+       .line_flag_num[0] = VOP_REG(RK3399_LINE_FLAG, 0xffff, 0),
+       .line_flag_num[1] = VOP_REG(RK3399_LINE_FLAG, 0xffff, 16),
        .cfg_done = VOP_REG_MASK(RK3399_REG_CFG_DONE, 0x1, 0),
 };