Re: [PATCH] drm/rockchip: vop: power off until vop standby take effect
From: Mark yao
Date: Sun Feb 01 2015 - 21:30:30 EST
On 2015å02æ02æ 10:07, Daniel Kurtz wrote:
Hi Mark, Heiko,
On Sat, Jan 31, 2015 at 4:41 PM, Mark Yao <mark.yao@xxxxxxxxxxxxxx> wrote:
Vop standby will take effect end of current frame,
if dsp_hold_valid_irq happen, it means vop standby complete.
we must wait standby complete when we want to disable aclk,
if not, memory bus maybe dead.
Signed-off-by: Mark Yao <mark.yao@xxxxxxxxxxxxxx>
---
drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 76 ++++++++++++++++++++++-----
1 file changed, 63 insertions(+), 13 deletions(-)
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
index fb25836..47ea61f 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
@@ -89,6 +89,7 @@ struct vop {
/* mutex vsync_ work */
struct mutex vsync_mutex;
bool vsync_work_pending;
+ struct completion dsp_hold_completion;
const struct vop_data *data;
@@ -382,6 +383,34 @@ static bool is_alpha_support(uint32_t format)
}
}
+static void vop_dsp_hold_valid_irq_enable(struct vop *vop)
+{
+ unsigned long flags;
+
+ BUG_ON(!vop->is_enabled);
Re: Heiko "use a WARN_ON":
If the VOP clock is off, then the system will just hang when trying to
write the VOP register so in this case, BUG_ON gives a more reliable
crash dump than the hang.
In this way, you are right, if vop clocks is disabled, write vop
register will hang system, and the WARN_ON
crash dump may be have no chance to print.
+
+ spin_lock_irqsave(&vop->irq_lock, flags);
+
+ vop_mask_write(vop, INTR_CTRL0, DSP_HOLD_VALID_INTR_MASK,
+ DSP_HOLD_VALID_INTR_EN(1));
+
+ spin_unlock_irqrestore(&vop->irq_lock, flags);
+}
+
+static void vop_dsp_hold_valid_irq_disable(struct vop *vop)
+{
+ unsigned long flags;
+
+ BUG_ON(!vop->is_enabled);
+
+ spin_lock_irqsave(&vop->irq_lock, flags);
+
+ vop_mask_write(vop, INTR_CTRL0, DSP_HOLD_VALID_INTR_MASK,
+ DSP_HOLD_VALID_INTR_EN(0));
+
+ spin_unlock_irqrestore(&vop->irq_lock, flags);
+}
+
static void vop_enable(struct drm_crtc *crtc)
{
struct vop *vop = to_vop(crtc);
@@ -454,26 +483,36 @@ static void vop_disable(struct drm_crtc *crtc)
drm_vblank_off(crtc->dev, vop->pipe);
- disable_irq(vop->irq);
-
/*
- * TODO: Since standby doesn't take effect until the next vblank,
- * when we turn off dclk below, the vop is probably still active.
+ * Vop standby will take effect until end of current frame,
"Vop standby will take effect at end of current frame"
OK
+ * if dsp hold valid irq happen, it means standby complete.
+ *
+ * we must wait standby complete when we want to disable aclk,
+ * if not, memory bus maybe dead.
*/
+ reinit_completion(&vop->dsp_hold_completion);
+ vop_dsp_hold_valid_irq_enable(vop);
+
spin_lock(&vop->reg_lock);
VOP_CTRL_SET(vop, standby, 1);
spin_unlock(&vop->reg_lock);
+ wait_for_completion(&vop->dsp_hold_completion);
+
+ vop_dsp_hold_valid_irq_disable(vop);
+
+ disable_irq(vop->irq);
+
vop->is_enabled = false;
+
/*
- * disable dclk to stop frame scan, so we can safely detach iommu,
+ * vop standby complete, so iommu detach is safe.
*/
- clk_disable(vop->dclk);
-
rockchip_drm_dma_detach_device(vop->drm_dev, vop->dev);
+ clk_disable(vop->dclk);
clk_disable(vop->aclk);
clk_disable(vop->hclk);
}
@@ -1086,6 +1125,7 @@ static irqreturn_t vop_isr(int irq, void *data)
struct vop *vop = data;
uint32_t intr0_reg, active_irqs;
unsigned long flags;
+ int ret = IRQ_NONE;
/*
* INTR_CTRL0 register has interrupt status, enable and clear bits, we
@@ -1104,15 +1144,24 @@ static irqreturn_t vop_isr(int irq, void *data)
if (!active_irqs)
return IRQ_NONE;
- /* Only Frame Start Interrupt is enabled; other irqs are spurious. */
- if (!(active_irqs & FS_INTR)) {
- DRM_ERROR("Unknown VOP IRQs: %#02x\n", active_irqs);
- return IRQ_NONE;
+ if (active_irqs & DSP_HOLD_VALID_INTR) {
+ if (!completion_done(&vop->dsp_hold_completion))
Why is this "completion_done" check needed?
I guess it doesn't help, but isn't strictly needed, since the
dsp_hold_completion is a one shot, right?
Right, the DSP_HOLD_VALID_INTR only happen when standby complete, one
standby one irq.
Mark
In any case, this should work as it is, so:
Reviewed-by: Daniel Kurtz <djkurtz@xxxxxxxxxxxx>
+ complete(&vop->dsp_hold_completion);
+ active_irqs &= ~DSP_HOLD_VALID_INTR;
+ ret = IRQ_HANDLED;
}
- drm_handle_vblank(vop->drm_dev, vop->pipe);
+ if (active_irqs & FS_INTR) {
+ drm_handle_vblank(vop->drm_dev, vop->pipe);
+ active_irqs &= ~FS_INTR;
+ ret = (vop->vsync_work_pending) ? IRQ_WAKE_THREAD : IRQ_HANDLED;
+ }
- return (vop->vsync_work_pending) ? IRQ_WAKE_THREAD : IRQ_HANDLED;
+ /* Unhandled irqs are spurious. */
+ if (active_irqs)
+ DRM_ERROR("Unknown VOP IRQs: %#02x\n", active_irqs);
+
+ return ret;
}
static int vop_create_crtc(struct vop *vop)
@@ -1194,6 +1243,7 @@ static int vop_create_crtc(struct vop *vop)
goto err_cleanup_crtc;
}
+ init_completion(&vop->dsp_hold_completion);
crtc->port = port;
vop->pipe = drm_crtc_index(crtc);
rockchip_register_crtc_funcs(drm_dev, &private_crtc_funcs, vop->pipe);
--
1.7.9.5
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