Read out the DISPBASE registers to decide on the FIFO size.
Signed-off-by: Eric Anholt <eric at anholt.net>
---
Mario: How about this for a squash into your commit? Here are the
values I dumped for cob_size:
[ 2.148314] [drm] Scaler 0 size 5232
[ 2.162239] [drm] Scaler 2 size 2048
[ 2.172957] [drm] Scaler 1 size 13456
drivers/gpu/drm/vc4/vc4_crtc.c | 23 +++++++++++++++++++++--
drivers/gpu/drm/vc4/vc4_regs.h | 18 +++++++++++++++++-
2 files changed, 38 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index baf962bce063..3b7db17c356d 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -55,6 +55,8 @@ struct vc4_crtc {
u8 lut_r[256];
u8 lut_g[256];
u8 lut_b[256];
+ /* Size in pixels of the COB memory allocated to this CRTC. */
+ u32 cob_size;
struct drm_pending_vblank_event *event;
};
@@ -195,8 +197,7 @@ int vc4_crtc_get_scanoutpos(struct drm_device *dev,
unsigned int crtc_id,
*hpos = 0;
/* This is the offset we need for translating hvs -> pv scanout pos. */
- /* XXX Find proper formula from hw docs instead of guesstimating? */
- fifo_lines = 2048 * 7 / mode->crtc_hdisplay;
+ fifo_lines = vc4_crtc->cob_size / mode->crtc_hdisplay;
if (fifo_lines > 0)
ret |= DRM_SCANOUTPOS_VALID;
@@ -873,6 +874,22 @@ static void vc4_set_crtc_possible_masks(struct drm_device
*drm,
}
}
+static void
+vc4_crtc_get_cob_allocation(struct vc4_crtc *vc4_crtc)
+{
+ struct drm_device *drm = vc4_crtc->base.dev;
+ struct vc4_dev *vc4 = to_vc4_dev(drm);
+ u32 dispbase = HVS_READ(SCALER_DISPBASEX(vc4_crtc->channel));
+ /* Top/base are supposed to be 4-pixel aligned, but the
+ * Raspberry Pi firmware fills the low bits (which are
+ * presumably ignored).
+ */
+ u32 top = VC4_GET_FIELD(dispbase, SCALER_DISPBASEX_TOP) & ~3;
+ u32 base = VC4_GET_FIELD(dispbase, SCALER_DISPBASEX_BASE) & ~3;
+
+ vc4_crtc->cob_size = top - base + 4;
+}
+
static int vc4_crtc_bind(struct device *dev, struct device *master, void *data)
{
struct platform_device *pdev = to_platform_device(dev);
@@ -949,6 +966,8 @@ static int vc4_crtc_bind(struct device *dev, struct device
*master, void *data)
crtc->cursor = cursor_plane;
}
+ vc4_crtc_get_cob_allocation(vc4_crtc);
+
CRTC_WRITE(PV_INTEN, 0);
CRTC_WRITE(PV_INTSTAT, PV_INT_VFP_START);
ret = devm_request_irq(dev, platform_get_irq(pdev, 0),
diff --git a/drivers/gpu/drm/vc4/vc4_regs.h b/drivers/gpu/drm/vc4/vc4_regs.h
index 63cdc28ff7bb..160942a9180e 100644
--- a/drivers/gpu/drm/vc4/vc4_regs.h
+++ b/drivers/gpu/drm/vc4/vc4_regs.h
@@ -366,7 +366,6 @@
# define SCALER_DISPBKGND_FILL BIT(24)
#define SCALER_DISPSTAT0 0x00000048
-#define SCALER_DISPBASE0 0x0000004c
# define SCALER_DISPSTATX_MODE_MASK VC4_MASK(31, 30)
# define SCALER_DISPSTATX_MODE_SHIFT 30
# define SCALER_DISPSTATX_MODE_DISABLED 0
@@ -379,6 +378,20 @@
# define SCALER_DISPSTATX_FRAME_COUNT_SHIFT 12
# define SCALER_DISPSTATX_LINE_MASK VC4_MASK(11, 0)
# define SCALER_DISPSTATX_LINE_SHIFT 0
+
+#define SCALER_DISPBASE0 0x0000004c
+/* Last pixel in the COB (display FIFO memory) allocated to this HVS
+ * channel. Must be 4-pixel aligned (and thus 4 pixels less than the
+ * next COB base).
+ */
+# define SCALER_DISPBASEX_TOP_MASK VC4_MASK(31, 16)
+# define SCALER_DISPBASEX_TOP_SHIFT 16
+/* First pixel in the COB (display FIFO memory) allocated to this HVS
+ * channel. Must be 4-pixel aligned.
+ */
+# define SCALER_DISPBASEX_BASE_MASK VC4_MASK(15, 0)
+# define SCALER_DISPBASEX_BASE_SHIFT 0
+
#define SCALER_DISPCTRL1 0x00000050
#define SCALER_DISPBKGND1 0x00000054
#define SCALER_DISPBKGNDX(x) (SCALER_DISPBKGND0 + \
@@ -389,6 +402,9 @@
(x) * (SCALER_DISPSTAT1 - \
SCALER_DISPSTAT0))
#define SCALER_DISPBASE1 0x0000005c
+#define SCALER_DISPBASEX(x) (SCALER_DISPBASE0 + \
+ (x) * (SCALER_DISPBASE1 - \
+ SCALER_DISPBASE0))
#define SCALER_DISPCTRL2 0x00000060
#define SCALER_DISPCTRLX(x) (SCALER_DISPCTRL0 + \
(x) * (SCALER_DISPCTRL1 - \
--
2.8.1
