openwrt/target/linux/bcm27xx/patches-5.4/950-0551-drm-vc4-crtc-Move-the-cob-allocation-outside-of-bind.patch

From e93fc4ed811c7dcc6b0c93716f760431fc645ba2 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime@cerno.tech>
Date: Thu, 26 Dec 2019 15:48:09 +0100
Subject: [PATCH] drm/vc4: crtc: Move the cob allocation outside of
 bind

The COB allocation depends on the HVS channel used for a given
pixelvalve.

While the channel allocation was entirely static in vc4, vc5 changes
that and at bind time, a pixelvalve can be assigned to multiple
HVS channels.

Let's prepare that rework by allocating the COB when it's actually
needed.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
 drivers/gpu/drm/vc4/vc4_crtc.c | 39 +++++++++++++++++-----------------
 drivers/gpu/drm/vc4/vc4_drv.h  |  2 --
 2 files changed, 20 insertions(+), 21 deletions(-)

--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -65,6 +65,23 @@ static const struct debugfs_reg32 crtc_r
 	VC4_REG32(PV_HACT_ACT),
 };
 
+static unsigned int
+vc4_crtc_get_cob_allocation(struct vc4_crtc *vc4_crtc, unsigned int channel)
+{
+	struct drm_device *drm = vc4_crtc->base.dev;
+	struct vc4_dev *vc4 = to_vc4_dev(drm);
+
+	u32 dispbase = HVS_READ(SCALER_DISPBASEX(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;
+
+	return top - base + 4;
+}
+
 bool vc4_crtc_get_scanoutpos(struct drm_device *dev, unsigned int crtc_id,
 			     bool in_vblank_irq, int *vpos, int *hpos,
 			     ktime_t *stime, ktime_t *etime,
@@ -73,6 +90,7 @@ bool vc4_crtc_get_scanoutpos(struct drm_
 	struct vc4_dev *vc4 = to_vc4_dev(dev);
 	struct drm_crtc *crtc = drm_crtc_from_index(dev, crtc_id);
 	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
+	unsigned int cob_size;
 	u32 val;
 	int fifo_lines;
 	int vblank_lines;
@@ -108,8 +126,9 @@ bool vc4_crtc_get_scanoutpos(struct drm_
 			*hpos += mode->crtc_htotal / 2;
 	}
 
+	cob_size = vc4_crtc_get_cob_allocation(vc4_crtc, vc4_crtc->channel);
 	/* This is the offset we need for translating hvs -> pv scanout pos. */
-	fifo_lines = vc4_crtc->cob_size / mode->crtc_hdisplay;
+	fifo_lines = cob_size / mode->crtc_hdisplay;
 
 	if (fifo_lines > 0)
 		ret = true;
@@ -1104,22 +1123,6 @@ static void vc4_set_crtc_possible_masks(
 	}
 }
 
-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);
@@ -1174,8 +1177,6 @@ static int vc4_crtc_bind(struct device *
 	 */
 	drm_crtc_enable_color_mgmt(crtc, 0, true, crtc->gamma_size);
 
-	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),
--- a/drivers/gpu/drm/vc4/vc4_drv.h
+++ b/drivers/gpu/drm/vc4/vc4_drv.h
@@ -477,8 +477,6 @@ 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;