Window properties are programmed through a shared aperture and have to
happen atomically. Also we do the read-update-write dance on some of the
shared regs.
To make sure that different functions don't stumble over each other
protect the register access with a mutex.
Signed-off-by: Lucas Stach <dev@xxxxxxxxxx>
---
We could probably make this a bit more fine grained, but this would add
some complexity and I don't really see a win there for now.
---
drivers/gpu/drm/tegra/dc.c | 13 +++++++++++++
drivers/gpu/drm/tegra/drm.h | 1 +
2 Dateien geändert, 14 Zeilen hinzugefügt(+)
diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c
index 54683e4..b256574 100644
--- a/drivers/gpu/drm/tegra/dc.c
+++ b/drivers/gpu/drm/tegra/dc.c
@@ -171,6 +171,8 @@ static int tegra_crtc_mode_set(struct drm_crtc *crtc,
return err;
}
+ mutex_lock(&dc->regs_mutex);
+
/* program display mode */
tegra_dc_set_timings(dc, mode);
@@ -269,6 +271,8 @@ static int tegra_crtc_mode_set(struct drm_crtc *crtc,
tegra_dc_writel(dc, 0xff00, DC_WIN_BLEND_NOKEY);
tegra_dc_writel(dc, 0xff00, DC_WIN_BLEND_1WIN);
+ mutex_unlock(&dc->regs_mutex);
+
return 0;
}
@@ -287,6 +291,8 @@ static void tegra_crtc_prepare(struct drm_crtc *crtc)
else
syncpt = SYNCPT_VBLANK0;
+ mutex_lock(&dc->regs_mutex);
+
/* initialize display controller */
tegra_dc_writel(dc, 0x00000100, DC_CMD_GENERAL_INCR_SYNCPT_CNTRL);
tegra_dc_writel(dc, 0x100 | syncpt, DC_CMD_CONT_SYNCPT_VSYNC);
@@ -320,6 +326,8 @@ static void tegra_crtc_prepare(struct drm_crtc *crtc)
value = VBLANK_INT | WIN_A_UF_INT | WIN_B_UF_INT | WIN_C_UF_INT;
tegra_dc_writel(dc, value, DC_CMD_INT_ENABLE);
+
+ mutex_unlock(&dc->regs_mutex);
}
static void tegra_crtc_commit(struct drm_crtc *crtc)
@@ -330,6 +338,8 @@ static void tegra_crtc_commit(struct drm_crtc *crtc)
update_mask = GENERAL_ACT_REQ | WIN_A_ACT_REQ;
+ mutex_lock(&dc->regs_mutex);
+
tegra_dc_writel(dc, update_mask << 8, DC_CMD_STATE_CONTROL);
value = tegra_dc_readl(dc, DC_CMD_INT_ENABLE);
@@ -341,6 +351,8 @@ static void tegra_crtc_commit(struct drm_crtc *crtc)
tegra_dc_writel(dc, value, DC_CMD_INT_MASK);
tegra_dc_writel(dc, update_mask, DC_CMD_STATE_CONTROL);
+
+ mutex_unlock(&dc->regs_mutex);
}
static void tegra_crtc_load_lut(struct drm_crtc *crtc)
@@ -747,6 +759,7 @@ static int tegra_dc_probe(struct platform_device *pdev)
return -ENOMEM;
INIT_LIST_HEAD(&dc->list);
+ mutex_init(&dc->regs_mutex);
dc->dev = &pdev->dev;
dc->clk = devm_clk_get(&pdev->dev, NULL);
diff --git a/drivers/gpu/drm/tegra/drm.h b/drivers/gpu/drm/tegra/drm.h
index 3a843a7..eae1f56 100644
--- a/drivers/gpu/drm/tegra/drm.h
+++ b/drivers/gpu/drm/tegra/drm.h
@@ -84,6 +84,7 @@ struct tegra_dc {
struct clk *clk;
+ struct mutex regs_mutex;
void __iomem *regs;
int irq;
--
1.7.11.7
--
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