Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 984 insertions, 0 deletions

diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
new file mode 100644
index 000000000..47990ecbf
--- /dev/null
+++ b/drivers/gpu/drm/vc4/vc4_hvs.c
@@ -0,0 +1,984 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2015 Broadcom
+ */
+
+/**
+ * DOC: VC4 HVS module.
+ *
+ * The Hardware Video Scaler (HVS) is the piece of hardware that does
+ * translation, scaling, colorspace conversion, and compositing of
+ * pixels stored in framebuffers into a FIFO of pixels going out to
+ * the Pixel Valve (CRTC).  It operates at the system clock rate (the
+ * system audio clock gate, specifically), which is much higher than
+ * the pixel clock rate.
+ *
+ * There is a single global HVS, with multiple output FIFOs that can
+ * be consumed by the PVs.  This file just manages the resources for
+ * the HVS, while the vc4_crtc.c code actually drives HVS setup for
+ * each CRTC.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/component.h>
+#include <linux/platform_device.h>
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_vblank.h>
+
+#include "vc4_drv.h"
+#include "vc4_regs.h"
+
+static const struct debugfs_reg32 hvs_regs[] = {
+	VC4_REG32(SCALER_DISPCTRL),
+	VC4_REG32(SCALER_DISPSTAT),
+	VC4_REG32(SCALER_DISPID),
+	VC4_REG32(SCALER_DISPECTRL),
+	VC4_REG32(SCALER_DISPPROF),
+	VC4_REG32(SCALER_DISPDITHER),
+	VC4_REG32(SCALER_DISPEOLN),
+	VC4_REG32(SCALER_DISPLIST0),
+	VC4_REG32(SCALER_DISPLIST1),
+	VC4_REG32(SCALER_DISPLIST2),
+	VC4_REG32(SCALER_DISPLSTAT),
+	VC4_REG32(SCALER_DISPLACT0),
+	VC4_REG32(SCALER_DISPLACT1),
+	VC4_REG32(SCALER_DISPLACT2),
+	VC4_REG32(SCALER_DISPCTRL0),
+	VC4_REG32(SCALER_DISPBKGND0),
+	VC4_REG32(SCALER_DISPSTAT0),
+	VC4_REG32(SCALER_DISPBASE0),
+	VC4_REG32(SCALER_DISPCTRL1),
+	VC4_REG32(SCALER_DISPBKGND1),
+	VC4_REG32(SCALER_DISPSTAT1),
+	VC4_REG32(SCALER_DISPBASE1),
+	VC4_REG32(SCALER_DISPCTRL2),
+	VC4_REG32(SCALER_DISPBKGND2),
+	VC4_REG32(SCALER_DISPSTAT2),
+	VC4_REG32(SCALER_DISPBASE2),
+	VC4_REG32(SCALER_DISPALPHA2),
+	VC4_REG32(SCALER_OLEDOFFS),
+	VC4_REG32(SCALER_OLEDCOEF0),
+	VC4_REG32(SCALER_OLEDCOEF1),
+	VC4_REG32(SCALER_OLEDCOEF2),
+};
+
+void vc4_hvs_dump_state(struct vc4_hvs *hvs)
+{
+	struct drm_device *drm = &hvs->vc4->base;
+	struct drm_printer p = drm_info_printer(&hvs->pdev->dev);
+	int idx, i;
+
+	if (!drm_dev_enter(drm, &idx))
+		return;
+
+	drm_print_regset32(&p, &hvs->regset);
+
+	DRM_INFO("HVS ctx:\n");
+	for (i = 0; i < 64; i += 4) {
+		DRM_INFO("0x%08x (%s): 0x%08x 0x%08x 0x%08x 0x%08x\n",
+			 i * 4, i < HVS_BOOTLOADER_DLIST_END ? "B" : "D",
+			 readl((u32 __iomem *)hvs->dlist + i + 0),
+			 readl((u32 __iomem *)hvs->dlist + i + 1),
+			 readl((u32 __iomem *)hvs->dlist + i + 2),
+			 readl((u32 __iomem *)hvs->dlist + i + 3));
+	}
+
+	drm_dev_exit(idx);
+}
+
+static int vc4_hvs_debugfs_underrun(struct seq_file *m, void *data)
+{
+	struct drm_info_node *node = m->private;
+	struct drm_device *dev = node->minor->dev;
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+	struct drm_printer p = drm_seq_file_printer(m);
+
+	drm_printf(&p, "%d\n", atomic_read(&vc4->underrun));
+
+	return 0;
+}
+
+static int vc4_hvs_debugfs_dlist(struct seq_file *m, void *data)
+{
+	struct drm_info_node *node = m->private;
+	struct drm_device *dev = node->minor->dev;
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+	struct vc4_hvs *hvs = vc4->hvs;
+	struct drm_printer p = drm_seq_file_printer(m);
+	unsigned int next_entry_start = 0;
+	unsigned int i, j;
+	u32 dlist_word, dispstat;
+
+	for (i = 0; i < SCALER_CHANNELS_COUNT; i++) {
+		dispstat = VC4_GET_FIELD(HVS_READ(SCALER_DISPSTATX(i)),
+					 SCALER_DISPSTATX_MODE);
+		if (dispstat == SCALER_DISPSTATX_MODE_DISABLED ||
+		    dispstat == SCALER_DISPSTATX_MODE_EOF) {
+			drm_printf(&p, "HVS chan %u disabled\n", i);
+			continue;
+		}
+
+		drm_printf(&p, "HVS chan %u:\n", i);
+
+		for (j = HVS_READ(SCALER_DISPLISTX(i)); j < 256; j++) {
+			dlist_word = readl((u32 __iomem *)vc4->hvs->dlist + j);
+			drm_printf(&p, "dlist: %02d: 0x%08x\n", j,
+				   dlist_word);
+			if (!next_entry_start ||
+			    next_entry_start == j) {
+				if (dlist_word & SCALER_CTL0_END)
+					break;
+				next_entry_start = j +
+					VC4_GET_FIELD(dlist_word,
+						      SCALER_CTL0_SIZE);
+			}
+		}
+	}
+
+	return 0;
+}
+
+/* The filter kernel is composed of dwords each containing 3 9-bit
+ * signed integers packed next to each other.
+ */
+#define VC4_INT_TO_COEFF(coeff) (coeff & 0x1ff)
+#define VC4_PPF_FILTER_WORD(c0, c1, c2)				\
+	((((c0) & 0x1ff) << 0) |				\
+	 (((c1) & 0x1ff) << 9) |				\
+	 (((c2) & 0x1ff) << 18))
+
+/* The whole filter kernel is arranged as the coefficients 0-16 going
+ * up, then a pad, then 17-31 going down and reversed within the
+ * dwords.  This means that a linear phase kernel (where it's
+ * symmetrical at the boundary between 15 and 16) has the last 5
+ * dwords matching the first 5, but reversed.
+ */
+#define VC4_LINEAR_PHASE_KERNEL(c0, c1, c2, c3, c4, c5, c6, c7, c8,	\
+				c9, c10, c11, c12, c13, c14, c15)	\
+	{VC4_PPF_FILTER_WORD(c0, c1, c2),				\
+	 VC4_PPF_FILTER_WORD(c3, c4, c5),				\
+	 VC4_PPF_FILTER_WORD(c6, c7, c8),				\
+	 VC4_PPF_FILTER_WORD(c9, c10, c11),				\
+	 VC4_PPF_FILTER_WORD(c12, c13, c14),				\
+	 VC4_PPF_FILTER_WORD(c15, c15, 0)}
+
+#define VC4_LINEAR_PHASE_KERNEL_DWORDS 6
+#define VC4_KERNEL_DWORDS (VC4_LINEAR_PHASE_KERNEL_DWORDS * 2 - 1)
+
+/* Recommended B=1/3, C=1/3 filter choice from Mitchell/Netravali.
+ * http://www.cs.utexas.edu/~fussell/courses/cs384g/lectures/mitchell/Mitchell.pdf
+ */
+static const u32 mitchell_netravali_1_3_1_3_kernel[] =
+	VC4_LINEAR_PHASE_KERNEL(0, -2, -6, -8, -10, -8, -3, 2, 18,
+				50, 82, 119, 155, 187, 213, 227);
+
+static int vc4_hvs_upload_linear_kernel(struct vc4_hvs *hvs,
+					struct drm_mm_node *space,
+					const u32 *kernel)
+{
+	int ret, i;
+	u32 __iomem *dst_kernel;
+
+	/*
+	 * NOTE: We don't need a call to drm_dev_enter()/drm_dev_exit()
+	 * here since that function is only called from vc4_hvs_bind().
+	 */
+
+	ret = drm_mm_insert_node(&hvs->dlist_mm, space, VC4_KERNEL_DWORDS);
+	if (ret) {
+		DRM_ERROR("Failed to allocate space for filter kernel: %d\n",
+			  ret);
+		return ret;
+	}
+
+	dst_kernel = hvs->dlist + space->start;
+
+	for (i = 0; i < VC4_KERNEL_DWORDS; i++) {
+		if (i < VC4_LINEAR_PHASE_KERNEL_DWORDS)
+			writel(kernel[i], &dst_kernel[i]);
+		else {
+			writel(kernel[VC4_KERNEL_DWORDS - i - 1],
+			       &dst_kernel[i]);
+		}
+	}
+
+	return 0;
+}
+
+static void vc4_hvs_lut_load(struct vc4_hvs *hvs,
+			     struct vc4_crtc *vc4_crtc)
+{
+	struct drm_device *drm = &hvs->vc4->base;
+	struct drm_crtc *crtc = &vc4_crtc->base;
+	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
+	int idx;
+	u32 i;
+
+	if (!drm_dev_enter(drm, &idx))
+		return;
+
+	/* The LUT memory is laid out with each HVS channel in order,
+	 * each of which takes 256 writes for R, 256 for G, then 256
+	 * for B.
+	 */
+	HVS_WRITE(SCALER_GAMADDR,
+		  SCALER_GAMADDR_AUTOINC |
+		  (vc4_state->assigned_channel * 3 * crtc->gamma_size));
+
+	for (i = 0; i < crtc->gamma_size; i++)
+		HVS_WRITE(SCALER_GAMDATA, vc4_crtc->lut_r[i]);
+	for (i = 0; i < crtc->gamma_size; i++)
+		HVS_WRITE(SCALER_GAMDATA, vc4_crtc->lut_g[i]);
+	for (i = 0; i < crtc->gamma_size; i++)
+		HVS_WRITE(SCALER_GAMDATA, vc4_crtc->lut_b[i]);
+
+	drm_dev_exit(idx);
+}
+
+static void vc4_hvs_update_gamma_lut(struct vc4_hvs *hvs,
+				     struct vc4_crtc *vc4_crtc)
+{
+	struct drm_crtc_state *crtc_state = vc4_crtc->base.state;
+	struct drm_color_lut *lut = crtc_state->gamma_lut->data;
+	u32 length = drm_color_lut_size(crtc_state->gamma_lut);
+	u32 i;
+
+	for (i = 0; i < length; i++) {
+		vc4_crtc->lut_r[i] = drm_color_lut_extract(lut[i].red, 8);
+		vc4_crtc->lut_g[i] = drm_color_lut_extract(lut[i].green, 8);
+		vc4_crtc->lut_b[i] = drm_color_lut_extract(lut[i].blue, 8);
+	}
+
+	vc4_hvs_lut_load(hvs, vc4_crtc);
+}
+
+u8 vc4_hvs_get_fifo_frame_count(struct vc4_hvs *hvs, unsigned int fifo)
+{
+	struct drm_device *drm = &hvs->vc4->base;
+	u8 field = 0;
+	int idx;
+
+	if (!drm_dev_enter(drm, &idx))
+		return 0;
+
+	switch (fifo) {
+	case 0:
+		field = VC4_GET_FIELD(HVS_READ(SCALER_DISPSTAT1),
+				      SCALER_DISPSTAT1_FRCNT0);
+		break;
+	case 1:
+		field = VC4_GET_FIELD(HVS_READ(SCALER_DISPSTAT1),
+				      SCALER_DISPSTAT1_FRCNT1);
+		break;
+	case 2:
+		field = VC4_GET_FIELD(HVS_READ(SCALER_DISPSTAT2),
+				      SCALER_DISPSTAT2_FRCNT2);
+		break;
+	}
+
+	drm_dev_exit(idx);
+	return field;
+}
+
+int vc4_hvs_get_fifo_from_output(struct vc4_hvs *hvs, unsigned int output)
+{
+	struct vc4_dev *vc4 = hvs->vc4;
+	u32 reg;
+	int ret;
+
+	if (!vc4->is_vc5)
+		return output;
+
+	/*
+	 * NOTE: We should probably use drm_dev_enter()/drm_dev_exit()
+	 * here, but this function is only used during the DRM device
+	 * initialization, so we should be fine.
+	 */
+
+	switch (output) {
+	case 0:
+		return 0;
+
+	case 1:
+		return 1;
+
+	case 2:
+		reg = HVS_READ(SCALER_DISPECTRL);
+		ret = FIELD_GET(SCALER_DISPECTRL_DSP2_MUX_MASK, reg);
+		if (ret == 0)
+			return 2;
+
+		return 0;
+
+	case 3:
+		reg = HVS_READ(SCALER_DISPCTRL);
+		ret = FIELD_GET(SCALER_DISPCTRL_DSP3_MUX_MASK, reg);
+		if (ret == 3)
+			return -EPIPE;
+
+		return ret;
+
+	case 4:
+		reg = HVS_READ(SCALER_DISPEOLN);
+		ret = FIELD_GET(SCALER_DISPEOLN_DSP4_MUX_MASK, reg);
+		if (ret == 3)
+			return -EPIPE;
+
+		return ret;
+
+	case 5:
+		reg = HVS_READ(SCALER_DISPDITHER);
+		ret = FIELD_GET(SCALER_DISPDITHER_DSP5_MUX_MASK, reg);
+		if (ret == 3)
+			return -EPIPE;
+
+		return ret;
+
+	default:
+		return -EPIPE;
+	}
+}
+
+static int vc4_hvs_init_channel(struct vc4_hvs *hvs, struct drm_crtc *crtc,
+				struct drm_display_mode *mode, bool oneshot)
+{
+	struct vc4_dev *vc4 = hvs->vc4;
+	struct drm_device *drm = &vc4->base;
+	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
+	struct vc4_crtc_state *vc4_crtc_state = to_vc4_crtc_state(crtc->state);
+	unsigned int chan = vc4_crtc_state->assigned_channel;
+	bool interlace = mode->flags & DRM_MODE_FLAG_INTERLACE;
+	u32 dispbkgndx;
+	u32 dispctrl;
+	int idx;
+
+	if (!drm_dev_enter(drm, &idx))
+		return -ENODEV;
+
+	HVS_WRITE(SCALER_DISPCTRLX(chan), 0);
+	HVS_WRITE(SCALER_DISPCTRLX(chan), SCALER_DISPCTRLX_RESET);
+	HVS_WRITE(SCALER_DISPCTRLX(chan), 0);
+
+	/* Turn on the scaler, which will wait for vstart to start
+	 * compositing.
+	 * When feeding the transposer, we should operate in oneshot
+	 * mode.
+	 */
+	dispctrl = SCALER_DISPCTRLX_ENABLE;
+	dispbkgndx = HVS_READ(SCALER_DISPBKGNDX(chan));
+
+	if (!vc4->is_vc5) {
+		dispctrl |= VC4_SET_FIELD(mode->hdisplay,
+					  SCALER_DISPCTRLX_WIDTH) |
+			    VC4_SET_FIELD(mode->vdisplay,
+					  SCALER_DISPCTRLX_HEIGHT) |
+			    (oneshot ? SCALER_DISPCTRLX_ONESHOT : 0);
+		dispbkgndx |= SCALER_DISPBKGND_AUTOHS;
+	} else {
+		dispctrl |= VC4_SET_FIELD(mode->hdisplay,
+					  SCALER5_DISPCTRLX_WIDTH) |
+			    VC4_SET_FIELD(mode->vdisplay,
+					  SCALER5_DISPCTRLX_HEIGHT) |
+			    (oneshot ? SCALER5_DISPCTRLX_ONESHOT : 0);
+		dispbkgndx &= ~SCALER5_DISPBKGND_BCK2BCK;
+	}
+
+	HVS_WRITE(SCALER_DISPCTRLX(chan), dispctrl);
+
+	dispbkgndx &= ~SCALER_DISPBKGND_GAMMA;
+	dispbkgndx &= ~SCALER_DISPBKGND_INTERLACE;
+
+	HVS_WRITE(SCALER_DISPBKGNDX(chan), dispbkgndx |
+		  ((!vc4->is_vc5) ? SCALER_DISPBKGND_GAMMA : 0) |
+		  (interlace ? SCALER_DISPBKGND_INTERLACE : 0));
+
+	/* Reload the LUT, since the SRAMs would have been disabled if
+	 * all CRTCs had SCALER_DISPBKGND_GAMMA unset at once.
+	 */
+	vc4_hvs_lut_load(hvs, vc4_crtc);
+
+	drm_dev_exit(idx);
+
+	return 0;
+}
+
+void vc4_hvs_stop_channel(struct vc4_hvs *hvs, unsigned int chan)
+{
+	struct drm_device *drm = &hvs->vc4->base;
+	int idx;
+
+	if (!drm_dev_enter(drm, &idx))
+		return;
+
+	if (HVS_READ(SCALER_DISPCTRLX(chan)) & SCALER_DISPCTRLX_ENABLE)
+		goto out;
+
+	HVS_WRITE(SCALER_DISPCTRLX(chan),
+		  HVS_READ(SCALER_DISPCTRLX(chan)) | SCALER_DISPCTRLX_RESET);
+	HVS_WRITE(SCALER_DISPCTRLX(chan),
+		  HVS_READ(SCALER_DISPCTRLX(chan)) & ~SCALER_DISPCTRLX_ENABLE);
+
+	/* Once we leave, the scaler should be disabled and its fifo empty. */
+	WARN_ON_ONCE(HVS_READ(SCALER_DISPCTRLX(chan)) & SCALER_DISPCTRLX_RESET);
+
+	WARN_ON_ONCE(VC4_GET_FIELD(HVS_READ(SCALER_DISPSTATX(chan)),
+				   SCALER_DISPSTATX_MODE) !=
+		     SCALER_DISPSTATX_MODE_DISABLED);
+
+	WARN_ON_ONCE((HVS_READ(SCALER_DISPSTATX(chan)) &
+		      (SCALER_DISPSTATX_FULL | SCALER_DISPSTATX_EMPTY)) !=
+		     SCALER_DISPSTATX_EMPTY);
+
+out:
+	drm_dev_exit(idx);
+}
+
+int vc4_hvs_atomic_check(struct drm_crtc *crtc, struct drm_atomic_state *state)
+{
+	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
+	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc_state);
+	struct drm_device *dev = crtc->dev;
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+	struct drm_plane *plane;
+	unsigned long flags;
+	const struct drm_plane_state *plane_state;
+	u32 dlist_count = 0;
+	int ret;
+
+	/* The pixelvalve can only feed one encoder (and encoders are
+	 * 1:1 with connectors.)
+	 */
+	if (hweight32(crtc_state->connector_mask) > 1)
+		return -EINVAL;
+
+	drm_atomic_crtc_state_for_each_plane_state(plane, plane_state, crtc_state)
+		dlist_count += vc4_plane_dlist_size(plane_state);
+
+	dlist_count++; /* Account for SCALER_CTL0_END. */
+
+	spin_lock_irqsave(&vc4->hvs->mm_lock, flags);
+	ret = drm_mm_insert_node(&vc4->hvs->dlist_mm, &vc4_state->mm,
+				 dlist_count);
+	spin_unlock_irqrestore(&vc4->hvs->mm_lock, flags);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static void vc4_hvs_install_dlist(struct drm_crtc *crtc)
+{
+	struct drm_device *dev = crtc->dev;
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+	struct vc4_hvs *hvs = vc4->hvs;
+	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
+	int idx;
+
+	if (!drm_dev_enter(dev, &idx))
+		return;
+
+	HVS_WRITE(SCALER_DISPLISTX(vc4_state->assigned_channel),
+		  vc4_state->mm.start);
+
+	drm_dev_exit(idx);
+}
+
+static void vc4_hvs_update_dlist(struct drm_crtc *crtc)
+{
+	struct drm_device *dev = crtc->dev;
+	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
+	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
+	unsigned long flags;
+
+	if (crtc->state->event) {
+		crtc->state->event->pipe = drm_crtc_index(crtc);
+
+		WARN_ON(drm_crtc_vblank_get(crtc) != 0);
+
+		spin_lock_irqsave(&dev->event_lock, flags);
+
+		if (!vc4_crtc->feeds_txp || vc4_state->txp_armed) {
+			vc4_crtc->event = crtc->state->event;
+			crtc->state->event = NULL;
+		}
+
+		spin_unlock_irqrestore(&dev->event_lock, flags);
+	}
+
+	spin_lock_irqsave(&vc4_crtc->irq_lock, flags);
+	vc4_crtc->current_dlist = vc4_state->mm.start;
+	spin_unlock_irqrestore(&vc4_crtc->irq_lock, flags);
+}
+
+void vc4_hvs_atomic_begin(struct drm_crtc *crtc,
+			  struct drm_atomic_state *state)
+{
+	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
+	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
+	unsigned long flags;
+
+	spin_lock_irqsave(&vc4_crtc->irq_lock, flags);
+	vc4_crtc->current_hvs_channel = vc4_state->assigned_channel;
+	spin_unlock_irqrestore(&vc4_crtc->irq_lock, flags);
+}
+
+void vc4_hvs_atomic_enable(struct drm_crtc *crtc,
+			   struct drm_atomic_state *state)
+{
+	struct drm_device *dev = crtc->dev;
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+	struct drm_display_mode *mode = &crtc->state->adjusted_mode;
+	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
+	bool oneshot = vc4_crtc->feeds_txp;
+
+	vc4_hvs_install_dlist(crtc);
+	vc4_hvs_update_dlist(crtc);
+	vc4_hvs_init_channel(vc4->hvs, crtc, mode, oneshot);
+}
+
+void vc4_hvs_atomic_disable(struct drm_crtc *crtc,
+			    struct drm_atomic_state *state)
+{
+	struct drm_device *dev = crtc->dev;
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+	struct drm_crtc_state *old_state = drm_atomic_get_old_crtc_state(state, crtc);
+	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(old_state);
+	unsigned int chan = vc4_state->assigned_channel;
+
+	vc4_hvs_stop_channel(vc4->hvs, chan);
+}
+
+void vc4_hvs_atomic_flush(struct drm_crtc *crtc,
+			  struct drm_atomic_state *state)
+{
+	struct drm_crtc_state *old_state = drm_atomic_get_old_crtc_state(state,
+									 crtc);
+	struct drm_device *dev = crtc->dev;
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+	struct vc4_hvs *hvs = vc4->hvs;
+	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
+	struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
+	unsigned int channel = vc4_state->assigned_channel;
+	struct drm_plane *plane;
+	struct vc4_plane_state *vc4_plane_state;
+	bool debug_dump_regs = false;
+	bool enable_bg_fill = false;
+	u32 __iomem *dlist_start = vc4->hvs->dlist + vc4_state->mm.start;
+	u32 __iomem *dlist_next = dlist_start;
+	int idx;
+
+	if (!drm_dev_enter(dev, &idx)) {
+		vc4_crtc_send_vblank(crtc);
+		return;
+	}
+
+	if (debug_dump_regs) {
+		DRM_INFO("CRTC %d HVS before:\n", drm_crtc_index(crtc));
+		vc4_hvs_dump_state(hvs);
+	}
+
+	/* Copy all the active planes' dlist contents to the hardware dlist. */
+	drm_atomic_crtc_for_each_plane(plane, crtc) {
+		/* Is this the first active plane? */
+		if (dlist_next == dlist_start) {
+			/* We need to enable background fill when a plane
+			 * could be alpha blending from the background, i.e.
+			 * where no other plane is underneath. It suffices to
+			 * consider the first active plane here since we set
+			 * needs_bg_fill such that either the first plane
+			 * already needs it or all planes on top blend from
+			 * the first or a lower plane.
+			 */
+			vc4_plane_state = to_vc4_plane_state(plane->state);
+			enable_bg_fill = vc4_plane_state->needs_bg_fill;
+		}
+
+		dlist_next += vc4_plane_write_dlist(plane, dlist_next);
+	}
+
+	writel(SCALER_CTL0_END, dlist_next);
+	dlist_next++;
+
+	WARN_ON_ONCE(dlist_next - dlist_start != vc4_state->mm.size);
+
+	if (enable_bg_fill)
+		/* This sets a black background color fill, as is the case
+		 * with other DRM drivers.
+		 */
+		HVS_WRITE(SCALER_DISPBKGNDX(channel),
+			  HVS_READ(SCALER_DISPBKGNDX(channel)) |
+			  SCALER_DISPBKGND_FILL);
+
+	/* Only update DISPLIST if the CRTC was already running and is not
+	 * being disabled.
+	 * vc4_crtc_enable() takes care of updating the dlist just after
+	 * re-enabling VBLANK interrupts and before enabling the engine.
+	 * If the CRTC is being disabled, there's no point in updating this
+	 * information.
+	 */
+	if (crtc->state->active && old_state->active) {
+		vc4_hvs_install_dlist(crtc);
+		vc4_hvs_update_dlist(crtc);
+	}
+
+	if (crtc->state->color_mgmt_changed) {
+		u32 dispbkgndx = HVS_READ(SCALER_DISPBKGNDX(channel));
+
+		if (crtc->state->gamma_lut) {
+			vc4_hvs_update_gamma_lut(hvs, vc4_crtc);
+			dispbkgndx |= SCALER_DISPBKGND_GAMMA;
+		} else {
+			/* Unsetting DISPBKGND_GAMMA skips the gamma lut step
+			 * in hardware, which is the same as a linear lut that
+			 * DRM expects us to use in absence of a user lut.
+			 */
+			dispbkgndx &= ~SCALER_DISPBKGND_GAMMA;
+		}
+		HVS_WRITE(SCALER_DISPBKGNDX(channel), dispbkgndx);
+	}
+
+	if (debug_dump_regs) {
+		DRM_INFO("CRTC %d HVS after:\n", drm_crtc_index(crtc));
+		vc4_hvs_dump_state(hvs);
+	}
+
+	drm_dev_exit(idx);
+}
+
+void vc4_hvs_mask_underrun(struct vc4_hvs *hvs, int channel)
+{
+	struct drm_device *drm = &hvs->vc4->base;
+	u32 dispctrl;
+	int idx;
+
+	if (!drm_dev_enter(drm, &idx))
+		return;
+
+	dispctrl = HVS_READ(SCALER_DISPCTRL);
+	dispctrl &= ~(hvs->vc4->is_vc5 ? SCALER5_DISPCTRL_DSPEISLUR(channel) :
+					 SCALER_DISPCTRL_DSPEISLUR(channel));
+
+	HVS_WRITE(SCALER_DISPCTRL, dispctrl);
+
+	drm_dev_exit(idx);
+}
+
+void vc4_hvs_unmask_underrun(struct vc4_hvs *hvs, int channel)
+{
+	struct drm_device *drm = &hvs->vc4->base;
+	u32 dispctrl;
+	int idx;
+
+	if (!drm_dev_enter(drm, &idx))
+		return;
+
+	dispctrl = HVS_READ(SCALER_DISPCTRL);
+	dispctrl |= (hvs->vc4->is_vc5 ? SCALER5_DISPCTRL_DSPEISLUR(channel) :
+					SCALER_DISPCTRL_DSPEISLUR(channel));
+
+	HVS_WRITE(SCALER_DISPSTAT,
+		  SCALER_DISPSTAT_EUFLOW(channel));
+	HVS_WRITE(SCALER_DISPCTRL, dispctrl);
+
+	drm_dev_exit(idx);
+}
+
+static void vc4_hvs_report_underrun(struct drm_device *dev)
+{
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+
+	atomic_inc(&vc4->underrun);
+	DRM_DEV_ERROR(dev->dev, "HVS underrun\n");
+}
+
+static irqreturn_t vc4_hvs_irq_handler(int irq, void *data)
+{
+	struct drm_device *dev = data;
+	struct vc4_dev *vc4 = to_vc4_dev(dev);
+	struct vc4_hvs *hvs = vc4->hvs;
+	irqreturn_t irqret = IRQ_NONE;
+	int channel;
+	u32 control;
+	u32 status;
+	u32 dspeislur;
+
+	/*
+	 * NOTE: We don't need to protect the register access using
+	 * drm_dev_enter() there because the interrupt handler lifetime
+	 * is tied to the device itself, and not to the DRM device.
+	 *
+	 * So when the device will be gone, one of the first thing we
+	 * will be doing will be to unregister the interrupt handler,
+	 * and then unregister the DRM device. drm_dev_enter() would
+	 * thus always succeed if we are here.
+	 */
+
+	status = HVS_READ(SCALER_DISPSTAT);
+	control = HVS_READ(SCALER_DISPCTRL);
+
+	for (channel = 0; channel < SCALER_CHANNELS_COUNT; channel++) {
+		dspeislur = vc4->is_vc5 ? SCALER5_DISPCTRL_DSPEISLUR(channel) :
+					  SCALER_DISPCTRL_DSPEISLUR(channel);
+		/* Interrupt masking is not always honored, so check it here. */
+		if (status & SCALER_DISPSTAT_EUFLOW(channel) &&
+		    control & dspeislur) {
+			vc4_hvs_mask_underrun(hvs, channel);
+			vc4_hvs_report_underrun(dev);
+
+			irqret = IRQ_HANDLED;
+		}
+	}
+
+	/* Clear every per-channel interrupt flag. */
+	HVS_WRITE(SCALER_DISPSTAT, SCALER_DISPSTAT_IRQMASK(0) |
+				   SCALER_DISPSTAT_IRQMASK(1) |
+				   SCALER_DISPSTAT_IRQMASK(2));
+
+	return irqret;
+}
+
+int vc4_hvs_debugfs_init(struct drm_minor *minor)
+{
+	struct drm_device *drm = minor->dev;
+	struct vc4_dev *vc4 = to_vc4_dev(drm);
+	struct vc4_hvs *hvs = vc4->hvs;
+	int ret;
+
+	if (!vc4->hvs)
+		return -ENODEV;
+
+	if (!vc4->is_vc5)
+		debugfs_create_bool("hvs_load_tracker", S_IRUGO | S_IWUSR,
+				    minor->debugfs_root,
+				    &vc4->load_tracker_enabled);
+
+	ret = vc4_debugfs_add_file(minor, "hvs_dlists",
+				   vc4_hvs_debugfs_dlist, NULL);
+	if (ret)
+		return ret;
+
+	ret = vc4_debugfs_add_file(minor, "hvs_underrun",
+				   vc4_hvs_debugfs_underrun, NULL);
+	if (ret)
+		return ret;
+
+	ret = vc4_debugfs_add_regset32(minor, "hvs_regs",
+				       &hvs->regset);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int vc4_hvs_bind(struct device *dev, struct device *master, void *data)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct drm_device *drm = dev_get_drvdata(master);
+	struct vc4_dev *vc4 = to_vc4_dev(drm);
+	struct vc4_hvs *hvs = NULL;
+	int ret;
+	u32 dispctrl;
+	u32 reg;
+
+	hvs = drmm_kzalloc(drm, sizeof(*hvs), GFP_KERNEL);
+	if (!hvs)
+		return -ENOMEM;
+	hvs->vc4 = vc4;
+	hvs->pdev = pdev;
+
+	hvs->regs = vc4_ioremap_regs(pdev, 0);
+	if (IS_ERR(hvs->regs))
+		return PTR_ERR(hvs->regs);
+
+	hvs->regset.base = hvs->regs;
+	hvs->regset.regs = hvs_regs;
+	hvs->regset.nregs = ARRAY_SIZE(hvs_regs);
+
+	if (vc4->is_vc5) {
+		hvs->core_clk = devm_clk_get(&pdev->dev, NULL);
+		if (IS_ERR(hvs->core_clk)) {
+			dev_err(&pdev->dev, "Couldn't get core clock\n");
+			return PTR_ERR(hvs->core_clk);
+		}
+
+		ret = clk_prepare_enable(hvs->core_clk);
+		if (ret) {
+			dev_err(&pdev->dev, "Couldn't enable the core clock\n");
+			return ret;
+		}
+	}
+
+	if (!vc4->is_vc5)
+		hvs->dlist = hvs->regs + SCALER_DLIST_START;
+	else
+		hvs->dlist = hvs->regs + SCALER5_DLIST_START;
+
+	spin_lock_init(&hvs->mm_lock);
+
+	/* Set up the HVS display list memory manager.  We never
+	 * overwrite the setup from the bootloader (just 128b out of
+	 * our 16K), since we don't want to scramble the screen when
+	 * transitioning from the firmware's boot setup to runtime.
+	 */
+	drm_mm_init(&hvs->dlist_mm,
+		    HVS_BOOTLOADER_DLIST_END,
+		    (SCALER_DLIST_SIZE >> 2) - HVS_BOOTLOADER_DLIST_END);
+
+	/* Set up the HVS LBM memory manager.  We could have some more
+	 * complicated data structure that allowed reuse of LBM areas
+	 * between planes when they don't overlap on the screen, but
+	 * for now we just allocate globally.
+	 */
+	if (!vc4->is_vc5)
+		/* 48k words of 2x12-bit pixels */
+		drm_mm_init(&hvs->lbm_mm, 0, 48 * 1024);
+	else
+		/* 60k words of 4x12-bit pixels */
+		drm_mm_init(&hvs->lbm_mm, 0, 60 * 1024);
+
+	/* Upload filter kernels.  We only have the one for now, so we
+	 * keep it around for the lifetime of the driver.
+	 */
+	ret = vc4_hvs_upload_linear_kernel(hvs,
+					   &hvs->mitchell_netravali_filter,
+					   mitchell_netravali_1_3_1_3_kernel);
+	if (ret)
+		return ret;
+
+	vc4->hvs = hvs;
+
+	reg = HVS_READ(SCALER_DISPECTRL);
+	reg &= ~SCALER_DISPECTRL_DSP2_MUX_MASK;
+	HVS_WRITE(SCALER_DISPECTRL,
+		  reg | VC4_SET_FIELD(0, SCALER_DISPECTRL_DSP2_MUX));
+
+	reg = HVS_READ(SCALER_DISPCTRL);
+	reg &= ~SCALER_DISPCTRL_DSP3_MUX_MASK;
+	HVS_WRITE(SCALER_DISPCTRL,
+		  reg | VC4_SET_FIELD(3, SCALER_DISPCTRL_DSP3_MUX));
+
+	reg = HVS_READ(SCALER_DISPEOLN);
+	reg &= ~SCALER_DISPEOLN_DSP4_MUX_MASK;
+	HVS_WRITE(SCALER_DISPEOLN,
+		  reg | VC4_SET_FIELD(3, SCALER_DISPEOLN_DSP4_MUX));
+
+	reg = HVS_READ(SCALER_DISPDITHER);
+	reg &= ~SCALER_DISPDITHER_DSP5_MUX_MASK;
+	HVS_WRITE(SCALER_DISPDITHER,
+		  reg | VC4_SET_FIELD(3, SCALER_DISPDITHER_DSP5_MUX));
+
+	dispctrl = HVS_READ(SCALER_DISPCTRL);
+
+	dispctrl |= SCALER_DISPCTRL_ENABLE;
+	dispctrl |= SCALER_DISPCTRL_DISPEIRQ(0) |
+		    SCALER_DISPCTRL_DISPEIRQ(1) |
+		    SCALER_DISPCTRL_DISPEIRQ(2);
+
+	if (!vc4->is_vc5)
+		dispctrl &= ~(SCALER_DISPCTRL_DMAEIRQ |
+			      SCALER_DISPCTRL_SLVWREIRQ |
+			      SCALER_DISPCTRL_SLVRDEIRQ |
+			      SCALER_DISPCTRL_DSPEIEOF(0) |
+			      SCALER_DISPCTRL_DSPEIEOF(1) |
+			      SCALER_DISPCTRL_DSPEIEOF(2) |
+			      SCALER_DISPCTRL_DSPEIEOLN(0) |
+			      SCALER_DISPCTRL_DSPEIEOLN(1) |
+			      SCALER_DISPCTRL_DSPEIEOLN(2) |
+			      SCALER_DISPCTRL_DSPEISLUR(0) |
+			      SCALER_DISPCTRL_DSPEISLUR(1) |
+			      SCALER_DISPCTRL_DSPEISLUR(2) |
+			      SCALER_DISPCTRL_SCLEIRQ);
+	else
+		dispctrl &= ~(SCALER_DISPCTRL_DMAEIRQ |
+			      SCALER5_DISPCTRL_SLVEIRQ |
+			      SCALER5_DISPCTRL_DSPEIEOF(0) |
+			      SCALER5_DISPCTRL_DSPEIEOF(1) |
+			      SCALER5_DISPCTRL_DSPEIEOF(2) |
+			      SCALER5_DISPCTRL_DSPEIEOLN(0) |
+			      SCALER5_DISPCTRL_DSPEIEOLN(1) |
+			      SCALER5_DISPCTRL_DSPEIEOLN(2) |
+			      SCALER5_DISPCTRL_DSPEISLUR(0) |
+			      SCALER5_DISPCTRL_DSPEISLUR(1) |
+			      SCALER5_DISPCTRL_DSPEISLUR(2) |
+			      SCALER_DISPCTRL_SCLEIRQ);
+
+
+	/* Set AXI panic mode.
+	 * VC4 panics when < 2 lines in FIFO.
+	 * VC5 panics when less than 1 line in the FIFO.
+	 */
+	dispctrl &= ~(SCALER_DISPCTRL_PANIC0_MASK |
+		      SCALER_DISPCTRL_PANIC1_MASK |
+		      SCALER_DISPCTRL_PANIC2_MASK);
+	dispctrl |= VC4_SET_FIELD(2, SCALER_DISPCTRL_PANIC0);
+	dispctrl |= VC4_SET_FIELD(2, SCALER_DISPCTRL_PANIC1);
+	dispctrl |= VC4_SET_FIELD(2, SCALER_DISPCTRL_PANIC2);
+
+	HVS_WRITE(SCALER_DISPCTRL, dispctrl);
+
+	ret = devm_request_irq(dev, platform_get_irq(pdev, 0),
+			       vc4_hvs_irq_handler, 0, "vc4 hvs", drm);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static void vc4_hvs_unbind(struct device *dev, struct device *master,
+			   void *data)
+{
+	struct drm_device *drm = dev_get_drvdata(master);
+	struct vc4_dev *vc4 = to_vc4_dev(drm);
+	struct vc4_hvs *hvs = vc4->hvs;
+	struct drm_mm_node *node, *next;
+
+	if (drm_mm_node_allocated(&vc4->hvs->mitchell_netravali_filter))
+		drm_mm_remove_node(&vc4->hvs->mitchell_netravali_filter);
+
+	drm_mm_for_each_node_safe(node, next, &vc4->hvs->dlist_mm)
+		drm_mm_remove_node(node);
+
+	drm_mm_takedown(&vc4->hvs->dlist_mm);
+
+	drm_mm_for_each_node_safe(node, next, &vc4->hvs->lbm_mm)
+		drm_mm_remove_node(node);
+	drm_mm_takedown(&vc4->hvs->lbm_mm);
+
+	clk_disable_unprepare(hvs->core_clk);
+
+	vc4->hvs = NULL;
+}
+
+static const struct component_ops vc4_hvs_ops = {
+	.bind   = vc4_hvs_bind,
+	.unbind = vc4_hvs_unbind,
+};
+
+static int vc4_hvs_dev_probe(struct platform_device *pdev)
+{
+	return component_add(&pdev->dev, &vc4_hvs_ops);
+}
+
+static int vc4_hvs_dev_remove(struct platform_device *pdev)
+{
+	component_del(&pdev->dev, &vc4_hvs_ops);
+	return 0;
+}
+
+static const struct of_device_id vc4_hvs_dt_match[] = {
+	{ .compatible = "brcm,bcm2711-hvs" },
+	{ .compatible = "brcm,bcm2835-hvs" },
+	{}
+};
+
+struct platform_driver vc4_hvs_driver = {
+	.probe = vc4_hvs_dev_probe,
+	.remove = vc4_hvs_dev_remove,
+	.driver = {
+		.name = "vc4_hvs",
+		.of_match_table = vc4_hvs_dt_match,
+	},
+};