drm/vc4: Add support for the transposer block
authorBoris Brezillon <boris.brezillon@free-electrons.com>
Tue, 3 Jul 2018 07:50:22 +0000 (09:50 +0200)
committerBoris Brezillon <boris.brezillon@bootlin.com>
Sat, 7 Jul 2018 05:54:46 +0000 (07:54 +0200)
The transposer block is providing support for mem-to-mem composition,
which is exposed as a drm_writeback connector in DRM.

Add a driver to support this feature.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20180703075022.15138-9-boris.brezillon@bootlin.com
Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
drivers/gpu/drm/vc4/Makefile
drivers/gpu/drm/vc4/vc4_crtc.c
drivers/gpu/drm/vc4/vc4_debugfs.c
drivers/gpu/drm/vc4/vc4_drv.c
drivers/gpu/drm/vc4/vc4_drv.h
drivers/gpu/drm/vc4/vc4_txp.c [new file with mode: 0644]

index 284e2b14cfbe0a291416973ce429ee4b9aa05300..26649b4c4dd8de41ab16a6f76f8e73dcac2525a1 100644 (file)
@@ -74,6 +74,12 @@ Required properties for DSI:
                The 3 clocks output from the DSI analog PHY: dsi[01]_byte,
                dsi[01]_ddr2, and dsi[01]_ddr
 
+Required properties for the TXP (writeback) block:
+- compatible:  Should be "brcm,bcm2835-txp"
+- reg:         Physical base address and length of the TXP block's registers
+- interrupts:  The interrupt number
+                 See bindings/interrupt-controller/brcm,bcm2835-armctrl-ic.txt
+
 [1] Documentation/devicetree/bindings/media/video-interfaces.txt
 
 Example:
index 4a3a868235f848698c3bcc062475a8d3e4518a69..b303703bc7f37e3f1b032096c0dc00a6d7326bb6 100644 (file)
@@ -19,6 +19,7 @@ vc4-y := \
        vc4_plane.o \
        vc4_render_cl.o \
        vc4_trace_points.o \
+       vc4_txp.o \
        vc4_v3d.o \
        vc4_validate.o \
        vc4_validate_shaders.o
index d222358fa8a701666aa0e7a0a70c51504fb08039..0e6a121858d13ec335ae0a1f19ad839123f9cbe6 100644 (file)
@@ -46,6 +46,8 @@ struct vc4_crtc_state {
        struct drm_crtc_state base;
        /* Dlist area for this CRTC configuration. */
        struct drm_mm_node mm;
+       bool feed_txp;
+       bool txp_armed;
 };
 
 static inline struct vc4_crtc_state *
@@ -324,10 +326,8 @@ static struct drm_encoder *vc4_get_crtc_encoder(struct drm_crtc *crtc)
        return NULL;
 }
 
-static void vc4_crtc_mode_set_nofb(struct drm_crtc *crtc)
+static void vc4_crtc_config_pv(struct drm_crtc *crtc)
 {
-       struct drm_device *dev = crtc->dev;
-       struct vc4_dev *vc4 = to_vc4_dev(dev);
        struct drm_encoder *encoder = vc4_get_crtc_encoder(crtc);
        struct vc4_encoder *vc4_encoder = to_vc4_encoder(encoder);
        struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
@@ -338,12 +338,6 @@ static void vc4_crtc_mode_set_nofb(struct drm_crtc *crtc)
        bool is_dsi = (vc4_encoder->type == VC4_ENCODER_TYPE_DSI0 ||
                       vc4_encoder->type == VC4_ENCODER_TYPE_DSI1);
        u32 format = is_dsi ? PV_CONTROL_FORMAT_DSIV_24 : PV_CONTROL_FORMAT_24;
-       bool debug_dump_regs = false;
-
-       if (debug_dump_regs) {
-               DRM_INFO("CRTC %d regs before:\n", drm_crtc_index(crtc));
-               vc4_crtc_dump_regs(vc4_crtc);
-       }
 
        /* Reset the PV fifo. */
        CRTC_WRITE(PV_CONTROL, 0);
@@ -419,6 +413,49 @@ static void vc4_crtc_mode_set_nofb(struct drm_crtc *crtc)
                                 PV_CONTROL_CLK_SELECT) |
                   PV_CONTROL_FIFO_CLR |
                   PV_CONTROL_EN);
+}
+
+static void vc4_crtc_mode_set_nofb(struct drm_crtc *crtc)
+{
+       struct drm_device *dev = crtc->dev;
+       struct vc4_dev *vc4 = to_vc4_dev(dev);
+       struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
+       struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
+       struct drm_display_mode *mode = &crtc->state->adjusted_mode;
+       bool interlace = mode->flags & DRM_MODE_FLAG_INTERLACE;
+       bool debug_dump_regs = false;
+
+       if (debug_dump_regs) {
+               DRM_INFO("CRTC %d regs before:\n", drm_crtc_index(crtc));
+               vc4_crtc_dump_regs(vc4_crtc);
+       }
+
+       if (vc4_crtc->channel == 2) {
+               u32 dispctrl;
+               u32 dsp3_mux;
+
+               /*
+                * SCALER_DISPCTRL_DSP3 = X, where X < 2 means 'connect DSP3 to
+                * FIFO X'.
+                * SCALER_DISPCTRL_DSP3 = 3 means 'disable DSP 3'.
+                *
+                * DSP3 is connected to FIFO2 unless the transposer is
+                * enabled. In this case, FIFO 2 is directly accessed by the
+                * TXP IP, and we need to disable the FIFO2 -> pixelvalve1
+                * route.
+                */
+               if (vc4_state->feed_txp)
+                       dsp3_mux = VC4_SET_FIELD(3, SCALER_DISPCTRL_DSP3_MUX);
+               else
+                       dsp3_mux = VC4_SET_FIELD(2, SCALER_DISPCTRL_DSP3_MUX);
+
+               dispctrl = HVS_READ(SCALER_DISPCTRL) &
+                          ~SCALER_DISPCTRL_DSP3_MUX_MASK;
+               HVS_WRITE(SCALER_DISPCTRL, dispctrl | dsp3_mux);
+       }
+
+       if (!vc4_state->feed_txp)
+               vc4_crtc_config_pv(crtc);
 
        HVS_WRITE(SCALER_DISPBKGNDX(vc4_crtc->channel),
                  SCALER_DISPBKGND_AUTOHS |
@@ -499,6 +536,13 @@ static void vc4_crtc_atomic_disable(struct drm_crtc *crtc,
        }
 }
 
+void vc4_crtc_txp_armed(struct drm_crtc_state *state)
+{
+       struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(state);
+
+       vc4_state->txp_armed = true;
+}
+
 static void vc4_crtc_update_dlist(struct drm_crtc *crtc)
 {
        struct drm_device *dev = crtc->dev;
@@ -514,8 +558,11 @@ static void vc4_crtc_update_dlist(struct drm_crtc *crtc)
                WARN_ON(drm_crtc_vblank_get(crtc) != 0);
 
                spin_lock_irqsave(&dev->event_lock, flags);
-               vc4_crtc->event = crtc->state->event;
-               crtc->state->event = NULL;
+
+               if (!vc4_state->feed_txp || vc4_state->txp_armed) {
+                       vc4_crtc->event = crtc->state->event;
+                       crtc->state->event = NULL;
+               }
 
                HVS_WRITE(SCALER_DISPLISTX(vc4_crtc->channel),
                          vc4_state->mm.start);
@@ -533,8 +580,8 @@ static void vc4_crtc_atomic_enable(struct drm_crtc *crtc,
        struct drm_device *dev = crtc->dev;
        struct vc4_dev *vc4 = to_vc4_dev(dev);
        struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
-       struct drm_crtc_state *state = crtc->state;
-       struct drm_display_mode *mode = &state->adjusted_mode;
+       struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
+       struct drm_display_mode *mode = &crtc->state->adjusted_mode;
 
        require_hvs_enabled(dev);
 
@@ -546,15 +593,21 @@ static void vc4_crtc_atomic_enable(struct drm_crtc *crtc,
 
        /* Turn on the scaler, which will wait for vstart to start
         * compositing.
+        * When feeding the transposer, we should operate in oneshot
+        * mode.
         */
        HVS_WRITE(SCALER_DISPCTRLX(vc4_crtc->channel),
                  VC4_SET_FIELD(mode->hdisplay, SCALER_DISPCTRLX_WIDTH) |
                  VC4_SET_FIELD(mode->vdisplay, SCALER_DISPCTRLX_HEIGHT) |
-                 SCALER_DISPCTRLX_ENABLE);
+                 SCALER_DISPCTRLX_ENABLE |
+                 (vc4_state->feed_txp ? SCALER_DISPCTRLX_ONESHOT : 0));
 
-       /* Turn on the pixel valve, which will emit the vstart signal. */
-       CRTC_WRITE(PV_V_CONTROL,
-                  CRTC_READ(PV_V_CONTROL) | PV_VCONTROL_VIDEN);
+       /* When feeding the transposer block the pixelvalve is unneeded and
+        * should not be enabled.
+        */
+       if (!vc4_state->feed_txp)
+               CRTC_WRITE(PV_V_CONTROL,
+                          CRTC_READ(PV_V_CONTROL) | PV_VCONTROL_VIDEN);
 }
 
 static enum drm_mode_status vc4_crtc_mode_valid(struct drm_crtc *crtc,
@@ -579,8 +632,10 @@ static int vc4_crtc_atomic_check(struct drm_crtc *crtc,
        struct drm_plane *plane;
        unsigned long flags;
        const struct drm_plane_state *plane_state;
+       struct drm_connector *conn;
+       struct drm_connector_state *conn_state;
        u32 dlist_count = 0;
-       int ret;
+       int ret, i;
 
        /* The pixelvalve can only feed one encoder (and encoders are
         * 1:1 with connectors.)
@@ -600,6 +655,24 @@ static int vc4_crtc_atomic_check(struct drm_crtc *crtc,
        if (ret)
                return ret;
 
+       for_each_new_connector_in_state(state->state, conn, conn_state, i) {
+               if (conn_state->crtc != crtc)
+                       continue;
+
+               /* The writeback connector is implemented using the transposer
+                * block which is directly taking its data from the HVS FIFO.
+                */
+               if (conn->connector_type == DRM_MODE_CONNECTOR_WRITEBACK) {
+                       state->no_vblank = true;
+                       vc4_state->feed_txp = true;
+               } else {
+                       state->no_vblank = false;
+                       vc4_state->feed_txp = false;
+               }
+
+               break;
+       }
+
        return 0;
 }
 
@@ -713,7 +786,8 @@ static void vc4_crtc_handle_page_flip(struct vc4_crtc *vc4_crtc)
 
        spin_lock_irqsave(&dev->event_lock, flags);
        if (vc4_crtc->event &&
-           (vc4_state->mm.start == HVS_READ(SCALER_DISPLACTX(chan)))) {
+           (vc4_state->mm.start == HVS_READ(SCALER_DISPLACTX(chan)) ||
+            vc4_state->feed_txp)) {
                drm_crtc_send_vblank_event(crtc, vc4_crtc->event);
                vc4_crtc->event = NULL;
                drm_crtc_vblank_put(crtc);
@@ -721,6 +795,13 @@ static void vc4_crtc_handle_page_flip(struct vc4_crtc *vc4_crtc)
        spin_unlock_irqrestore(&dev->event_lock, flags);
 }
 
+void vc4_crtc_handle_vblank(struct vc4_crtc *crtc)
+{
+       crtc->t_vblank = ktime_get();
+       drm_crtc_handle_vblank(&crtc->base);
+       vc4_crtc_handle_page_flip(crtc);
+}
+
 static irqreturn_t vc4_crtc_irq_handler(int irq, void *data)
 {
        struct vc4_crtc *vc4_crtc = data;
@@ -728,10 +809,8 @@ static irqreturn_t vc4_crtc_irq_handler(int irq, void *data)
        irqreturn_t ret = IRQ_NONE;
 
        if (stat & PV_INT_VFP_START) {
-               vc4_crtc->t_vblank = ktime_get();
                CRTC_WRITE(PV_INTSTAT, PV_INT_VFP_START);
-               drm_crtc_handle_vblank(&vc4_crtc->base);
-               vc4_crtc_handle_page_flip(vc4_crtc);
+               vc4_crtc_handle_vblank(vc4_crtc);
                ret = IRQ_HANDLED;
        }
 
@@ -884,12 +963,15 @@ static int vc4_page_flip(struct drm_crtc *crtc,
 
 static struct drm_crtc_state *vc4_crtc_duplicate_state(struct drm_crtc *crtc)
 {
-       struct vc4_crtc_state *vc4_state;
+       struct vc4_crtc_state *vc4_state, *old_vc4_state;
 
        vc4_state = kzalloc(sizeof(*vc4_state), GFP_KERNEL);
        if (!vc4_state)
                return NULL;
 
+       old_vc4_state = to_vc4_crtc_state(crtc->state);
+       vc4_state->feed_txp = old_vc4_state->feed_txp;
+
        __drm_atomic_helper_crtc_duplicate_state(crtc, &vc4_state->base);
        return &vc4_state->base;
 }
@@ -987,9 +1069,17 @@ static void vc4_set_crtc_possible_masks(struct drm_device *drm,
        struct drm_encoder *encoder;
 
        drm_for_each_encoder(encoder, drm) {
-               struct vc4_encoder *vc4_encoder = to_vc4_encoder(encoder);
+               struct vc4_encoder *vc4_encoder;
                int i;
 
+               /* HVS FIFO2 can feed the TXP IP. */
+               if (crtc_data->hvs_channel == 2 &&
+                   encoder->encoder_type == DRM_MODE_ENCODER_VIRTUAL) {
+                       encoder->possible_crtcs |= drm_crtc_mask(crtc);
+                       continue;
+               }
+
+               vc4_encoder = to_vc4_encoder(encoder);
                for (i = 0; i < ARRAY_SIZE(crtc_data->encoder_types); i++) {
                        if (vc4_encoder->type == encoder_types[i]) {
                                vc4_encoder->clock_select = i;
index 5db06bdb5f27b28eca3bfee651d6ccf660c3e351..7a0003de71ab0bf74d07549dd2df985bb0afa493 100644 (file)
@@ -21,6 +21,7 @@ static const struct drm_info_list vc4_debugfs_list[] = {
        {"dsi1_regs", vc4_dsi_debugfs_regs, 0, (void *)(uintptr_t)1},
        {"hdmi_regs", vc4_hdmi_debugfs_regs, 0},
        {"vec_regs", vc4_vec_debugfs_regs, 0},
+       {"txp_regs", vc4_txp_debugfs_regs, 0},
        {"hvs_regs", vc4_hvs_debugfs_regs, 0},
        {"crtc0_regs", vc4_crtc_debugfs_regs, 0, (void *)(uintptr_t)0},
        {"crtc1_regs", vc4_crtc_debugfs_regs, 0, (void *)(uintptr_t)1},
index 466d0a27b41510085a93b4119bb737d33b8af1a0..e42fd5ec41cc9e180605d9f0f47036ffa4d4db64 100644 (file)
@@ -344,6 +344,7 @@ static struct platform_driver *const component_drivers[] = {
        &vc4_vec_driver,
        &vc4_dpi_driver,
        &vc4_dsi_driver,
+       &vc4_txp_driver,
        &vc4_hvs_driver,
        &vc4_crtc_driver,
        &vc4_v3d_driver,
index eace76c621a183322c2ebbaae0a8a5d9bae323f7..bd6ef1f318220556e067b158936f9d1f6447eedb 100644 (file)
@@ -73,6 +73,7 @@ struct vc4_dev {
        struct vc4_dpi *dpi;
        struct vc4_dsi *dsi1;
        struct vc4_vec *vec;
+       struct vc4_txp *txp;
 
        struct vc4_hang_state *hang_state;
 
@@ -698,6 +699,8 @@ 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,
                             const struct drm_display_mode *mode);
+void vc4_crtc_handle_vblank(struct vc4_crtc *crtc);
+void vc4_crtc_txp_armed(struct drm_crtc_state *state);
 
 /* vc4_debugfs.c */
 int vc4_debugfs_init(struct drm_minor *minor);
@@ -745,6 +748,10 @@ int vc4_hdmi_debugfs_regs(struct seq_file *m, void *unused);
 extern struct platform_driver vc4_vec_driver;
 int vc4_vec_debugfs_regs(struct seq_file *m, void *unused);
 
+/* vc4_txp.c */
+extern struct platform_driver vc4_txp_driver;
+int vc4_txp_debugfs_regs(struct seq_file *m, void *unused);
+
 /* vc4_irq.c */
 irqreturn_t vc4_irq(int irq, void *arg);
 void vc4_irq_preinstall(struct drm_device *dev);
diff --git a/drivers/gpu/drm/vc4/vc4_txp.c b/drivers/gpu/drm/vc4/vc4_txp.c
new file mode 100644 (file)
index 0000000..6e23c50
--- /dev/null
@@ -0,0 +1,477 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright © 2018 Broadcom
+ *
+ * Authors:
+ *     Eric Anholt <eric@anholt.net>
+ *     Boris Brezillon <boris.brezillon@bootlin.com>
+ */
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_edid.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_writeback.h>
+#include <linux/clk.h>
+#include <linux/component.h>
+#include <linux/of_graph.h>
+#include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
+
+#include "vc4_drv.h"
+#include "vc4_regs.h"
+
+/* Base address of the output.  Raster formats must be 4-byte aligned,
+ * T and LT must be 16-byte aligned or maybe utile-aligned (docs are
+ * inconsistent, but probably utile).
+ */
+#define TXP_DST_PTR            0x00
+
+/* Pitch in bytes for raster images, 16-byte aligned.  For tiled, it's
+ * the width in tiles.
+ */
+#define TXP_DST_PITCH          0x04
+/* For T-tiled imgaes, DST_PITCH should be the number of tiles wide,
+ * shifted up.
+ */
+# define TXP_T_TILE_WIDTH_SHIFT                7
+/* For LT-tiled images, DST_PITCH should be the number of utiles wide,
+ * shifted up.
+ */
+# define TXP_LT_TILE_WIDTH_SHIFT       4
+
+/* Pre-rotation width/height of the image.  Must match HVS config.
+ *
+ * If TFORMAT and 32-bit, limit is 1920 for 32-bit and 3840 to 16-bit
+ * and width/height must be tile or utile-aligned as appropriate.  If
+ * transposing (rotating), width is limited to 1920.
+ *
+ * Height is limited to various numbers between 4088 and 4095.  I'd
+ * just use 4088 to be safe.
+ */
+#define TXP_DIM                        0x08
+# define TXP_HEIGHT_SHIFT              16
+# define TXP_HEIGHT_MASK               GENMASK(31, 16)
+# define TXP_WIDTH_SHIFT               0
+# define TXP_WIDTH_MASK                        GENMASK(15, 0)
+
+#define TXP_DST_CTRL           0x0c
+/* These bits are set to 0x54 */
+#define TXP_PILOT_SHIFT                        24
+#define TXP_PILOT_MASK                 GENMASK(31, 24)
+/* Bits 22-23 are set to 0x01 */
+#define TXP_VERSION_SHIFT              22
+#define TXP_VERSION_MASK               GENMASK(23, 22)
+
+/* Powers down the internal memory. */
+# define TXP_POWERDOWN                 BIT(21)
+
+/* Enables storing the alpha component in 8888/4444, instead of
+ * filling with ~ALPHA_INVERT.
+ */
+# define TXP_ALPHA_ENABLE              BIT(20)
+
+/* 4 bits, each enables stores for a channel in each set of 4 bytes.
+ * Set to 0xf for normal operation.
+ */
+# define TXP_BYTE_ENABLE_SHIFT         16
+# define TXP_BYTE_ENABLE_MASK          GENMASK(19, 16)
+
+/* Debug: Generate VSTART again at EOF. */
+# define TXP_VSTART_AT_EOF             BIT(15)
+
+/* Debug: Terminate the current frame immediately.  Stops AXI
+ * writes.
+ */
+# define TXP_ABORT                     BIT(14)
+
+# define TXP_DITHER                    BIT(13)
+
+/* Inverts alpha if TXP_ALPHA_ENABLE, chooses fill value for
+ * !TXP_ALPHA_ENABLE.
+ */
+# define TXP_ALPHA_INVERT              BIT(12)
+
+/* Note: I've listed the channels here in high bit (in byte 3/2/1) to
+ * low bit (in byte 0) order.
+ */
+# define TXP_FORMAT_SHIFT              8
+# define TXP_FORMAT_MASK               GENMASK(11, 8)
+# define TXP_FORMAT_ABGR4444           0
+# define TXP_FORMAT_ARGB4444           1
+# define TXP_FORMAT_BGRA4444           2
+# define TXP_FORMAT_RGBA4444           3
+# define TXP_FORMAT_BGR565             6
+# define TXP_FORMAT_RGB565             7
+/* 888s are non-rotated, raster-only */
+# define TXP_FORMAT_BGR888             8
+# define TXP_FORMAT_RGB888             9
+# define TXP_FORMAT_ABGR8888           12
+# define TXP_FORMAT_ARGB8888           13
+# define TXP_FORMAT_BGRA8888           14
+# define TXP_FORMAT_RGBA8888           15
+
+/* If TFORMAT is set, generates LT instead of T format. */
+# define TXP_LINEAR_UTILE              BIT(7)
+
+/* Rotate output by 90 degrees. */
+# define TXP_TRANSPOSE                 BIT(6)
+
+/* Generate a tiled format for V3D. */
+# define TXP_TFORMAT                   BIT(5)
+
+/* Generates some undefined test mode output. */
+# define TXP_TEST_MODE                 BIT(4)
+
+/* Request odd field from HVS. */
+# define TXP_FIELD                     BIT(3)
+
+/* Raise interrupt when idle. */
+# define TXP_EI                                BIT(2)
+
+/* Set when generating a frame, clears when idle. */
+# define TXP_BUSY                      BIT(1)
+
+/* Starts a frame.  Self-clearing. */
+# define TXP_GO                                BIT(0)
+
+/* Number of lines received and committed to memory. */
+#define TXP_PROGRESS           0x10
+
+#define TXP_READ(offset) readl(txp->regs + (offset))
+#define TXP_WRITE(offset, val) writel(val, txp->regs + (offset))
+
+struct vc4_txp {
+       struct platform_device *pdev;
+
+       struct drm_writeback_connector connector;
+
+       void __iomem *regs;
+};
+
+static inline struct vc4_txp *encoder_to_vc4_txp(struct drm_encoder *encoder)
+{
+       return container_of(encoder, struct vc4_txp, connector.encoder);
+}
+
+static inline struct vc4_txp *connector_to_vc4_txp(struct drm_connector *conn)
+{
+       return container_of(conn, struct vc4_txp, connector.base);
+}
+
+#define TXP_REG(reg) { reg, #reg }
+static const struct {
+       u32 reg;
+       const char *name;
+} txp_regs[] = {
+       TXP_REG(TXP_DST_PTR),
+       TXP_REG(TXP_DST_PITCH),
+       TXP_REG(TXP_DIM),
+       TXP_REG(TXP_DST_CTRL),
+       TXP_REG(TXP_PROGRESS),
+};
+
+#ifdef CONFIG_DEBUG_FS
+int vc4_txp_debugfs_regs(struct seq_file *m, void *unused)
+{
+       struct drm_info_node *node = (struct drm_info_node *)m->private;
+       struct drm_device *dev = node->minor->dev;
+       struct vc4_dev *vc4 = to_vc4_dev(dev);
+       struct vc4_txp *txp = vc4->txp;
+       int i;
+
+       if (!txp)
+               return 0;
+
+       for (i = 0; i < ARRAY_SIZE(txp_regs); i++) {
+               seq_printf(m, "%s (0x%04x): 0x%08x\n",
+                          txp_regs[i].name, txp_regs[i].reg,
+                          TXP_READ(txp_regs[i].reg));
+       }
+
+       return 0;
+}
+#endif
+
+static int vc4_txp_connector_get_modes(struct drm_connector *connector)
+{
+       struct drm_device *dev = connector->dev;
+
+       return drm_add_modes_noedid(connector, dev->mode_config.max_width,
+                                   dev->mode_config.max_height);
+}
+
+static enum drm_mode_status
+vc4_txp_connector_mode_valid(struct drm_connector *connector,
+                            struct drm_display_mode *mode)
+{
+       struct drm_device *dev = connector->dev;
+       struct drm_mode_config *mode_config = &dev->mode_config;
+       int w = mode->hdisplay, h = mode->vdisplay;
+
+       if (w < mode_config->min_width || w > mode_config->max_width)
+               return MODE_BAD_HVALUE;
+
+       if (h < mode_config->min_height || h > mode_config->max_height)
+               return MODE_BAD_VVALUE;
+
+       return MODE_OK;
+}
+
+static const u32 drm_fmts[] = {
+       DRM_FORMAT_RGB888,
+       DRM_FORMAT_BGR888,
+       DRM_FORMAT_XRGB8888,
+       DRM_FORMAT_XBGR8888,
+       DRM_FORMAT_ARGB8888,
+       DRM_FORMAT_ABGR8888,
+       DRM_FORMAT_RGBX8888,
+       DRM_FORMAT_BGRX8888,
+       DRM_FORMAT_RGBA8888,
+       DRM_FORMAT_BGRA8888,
+};
+
+static const u32 txp_fmts[] = {
+       TXP_FORMAT_RGB888,
+       TXP_FORMAT_BGR888,
+       TXP_FORMAT_ARGB8888,
+       TXP_FORMAT_ABGR8888,
+       TXP_FORMAT_ARGB8888,
+       TXP_FORMAT_ABGR8888,
+       TXP_FORMAT_RGBA8888,
+       TXP_FORMAT_BGRA8888,
+       TXP_FORMAT_RGBA8888,
+       TXP_FORMAT_BGRA8888,
+};
+
+static int vc4_txp_connector_atomic_check(struct drm_connector *conn,
+                                       struct drm_connector_state *conn_state)
+{
+       struct drm_crtc_state *crtc_state;
+       struct drm_gem_cma_object *gem;
+       struct drm_framebuffer *fb;
+       int i;
+
+       if (!conn_state->writeback_job || !conn_state->writeback_job->fb)
+               return 0;
+
+       crtc_state = drm_atomic_get_new_crtc_state(conn_state->state,
+                                                  conn_state->crtc);
+
+       fb = conn_state->writeback_job->fb;
+       if (fb->width != crtc_state->mode.hdisplay ||
+           fb->height != crtc_state->mode.vdisplay) {
+               DRM_DEBUG_KMS("Invalid framebuffer size %ux%u\n",
+                             fb->width, fb->height);
+               return -EINVAL;
+       }
+
+       for (i = 0; i < ARRAY_SIZE(drm_fmts); i++) {
+               if (fb->format->format == drm_fmts[i])
+                       break;
+       }
+
+       if (i == ARRAY_SIZE(drm_fmts))
+               return -EINVAL;
+
+       gem = drm_fb_cma_get_gem_obj(fb, 0);
+
+       /* Pitch must be aligned on 16 bytes. */
+       if (fb->pitches[0] & GENMASK(3, 0))
+               return -EINVAL;
+
+       vc4_crtc_txp_armed(crtc_state);
+
+       return 0;
+}
+
+static void vc4_txp_connector_atomic_commit(struct drm_connector *conn,
+                                       struct drm_connector_state *conn_state)
+{
+       struct vc4_txp *txp = connector_to_vc4_txp(conn);
+       struct drm_gem_cma_object *gem;
+       struct drm_display_mode *mode;
+       struct drm_framebuffer *fb;
+       u32 ctrl;
+       int i;
+
+       if (WARN_ON(!conn_state->writeback_job ||
+                   !conn_state->writeback_job->fb))
+               return;
+
+       mode = &conn_state->crtc->state->adjusted_mode;
+       fb = conn_state->writeback_job->fb;
+
+       for (i = 0; i < ARRAY_SIZE(drm_fmts); i++) {
+               if (fb->format->format == drm_fmts[i])
+                       break;
+       }
+
+       if (WARN_ON(i == ARRAY_SIZE(drm_fmts)))
+               return;
+
+       ctrl = TXP_GO | TXP_VSTART_AT_EOF | TXP_EI |
+              VC4_SET_FIELD(0xf, TXP_BYTE_ENABLE) |
+              VC4_SET_FIELD(txp_fmts[i], TXP_FORMAT);
+
+       if (fb->format->has_alpha)
+               ctrl |= TXP_ALPHA_ENABLE;
+
+       gem = drm_fb_cma_get_gem_obj(fb, 0);
+       TXP_WRITE(TXP_DST_PTR, gem->paddr + fb->offsets[0]);
+       TXP_WRITE(TXP_DST_PITCH, fb->pitches[0]);
+       TXP_WRITE(TXP_DIM,
+                 VC4_SET_FIELD(mode->hdisplay, TXP_WIDTH) |
+                 VC4_SET_FIELD(mode->vdisplay, TXP_HEIGHT));
+
+       TXP_WRITE(TXP_DST_CTRL, ctrl);
+
+       drm_writeback_queue_job(&txp->connector, conn_state->writeback_job);
+}
+
+static const struct drm_connector_helper_funcs vc4_txp_connector_helper_funcs = {
+       .get_modes = vc4_txp_connector_get_modes,
+       .mode_valid = vc4_txp_connector_mode_valid,
+       .atomic_check = vc4_txp_connector_atomic_check,
+       .atomic_commit = vc4_txp_connector_atomic_commit,
+};
+
+static enum drm_connector_status
+vc4_txp_connector_detect(struct drm_connector *connector, bool force)
+{
+       return connector_status_connected;
+}
+
+static void vc4_txp_connector_destroy(struct drm_connector *connector)
+{
+       drm_connector_unregister(connector);
+       drm_connector_cleanup(connector);
+}
+
+static const struct drm_connector_funcs vc4_txp_connector_funcs = {
+       .detect = vc4_txp_connector_detect,
+       .fill_modes = drm_helper_probe_single_connector_modes,
+       .destroy = vc4_txp_connector_destroy,
+       .reset = drm_atomic_helper_connector_reset,
+       .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
+       .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+static void vc4_txp_encoder_disable(struct drm_encoder *encoder)
+{
+       struct vc4_txp *txp = encoder_to_vc4_txp(encoder);
+
+       if (TXP_READ(TXP_DST_CTRL) & TXP_BUSY) {
+               unsigned long timeout = jiffies + msecs_to_jiffies(1000);
+
+               TXP_WRITE(TXP_DST_CTRL, TXP_ABORT);
+
+               while (TXP_READ(TXP_DST_CTRL) & TXP_BUSY &&
+                      time_before(jiffies, timeout))
+                       ;
+
+               WARN_ON(TXP_READ(TXP_DST_CTRL) & TXP_BUSY);
+       }
+
+       TXP_WRITE(TXP_DST_CTRL, TXP_POWERDOWN);
+}
+
+static const struct drm_encoder_helper_funcs vc4_txp_encoder_helper_funcs = {
+       .disable = vc4_txp_encoder_disable,
+};
+
+static irqreturn_t vc4_txp_interrupt(int irq, void *data)
+{
+       struct vc4_txp *txp = data;
+
+       TXP_WRITE(TXP_DST_CTRL, TXP_READ(TXP_DST_CTRL) & ~TXP_EI);
+       vc4_crtc_handle_vblank(to_vc4_crtc(txp->connector.base.state->crtc));
+       drm_writeback_signal_completion(&txp->connector, 0);
+
+       return IRQ_HANDLED;
+}
+
+static int vc4_txp_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_txp *txp;
+       int ret, irq;
+
+       irq = platform_get_irq(pdev, 0);
+       if (irq < 0)
+               return irq;
+
+       txp = devm_kzalloc(dev, sizeof(*txp), GFP_KERNEL);
+       if (!txp)
+               return -ENOMEM;
+
+       txp->pdev = pdev;
+
+       txp->regs = vc4_ioremap_regs(pdev, 0);
+       if (IS_ERR(txp->regs))
+               return PTR_ERR(txp->regs);
+
+       drm_connector_helper_add(&txp->connector.base,
+                                &vc4_txp_connector_helper_funcs);
+       ret = drm_writeback_connector_init(drm, &txp->connector,
+                                          &vc4_txp_connector_funcs,
+                                          &vc4_txp_encoder_helper_funcs,
+                                          drm_fmts, ARRAY_SIZE(drm_fmts));
+       if (ret)
+               return ret;
+
+       ret = devm_request_irq(dev, irq, vc4_txp_interrupt, 0,
+                              dev_name(dev), txp);
+       if (ret)
+               return ret;
+
+       dev_set_drvdata(dev, txp);
+       vc4->txp = txp;
+
+       return 0;
+}
+
+static void vc4_txp_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_txp *txp = dev_get_drvdata(dev);
+
+       vc4_txp_connector_destroy(&txp->connector.base);
+
+       vc4->txp = NULL;
+}
+
+static const struct component_ops vc4_txp_ops = {
+       .bind   = vc4_txp_bind,
+       .unbind = vc4_txp_unbind,
+};
+
+static int vc4_txp_probe(struct platform_device *pdev)
+{
+       return component_add(&pdev->dev, &vc4_txp_ops);
+}
+
+static int vc4_txp_remove(struct platform_device *pdev)
+{
+       component_del(&pdev->dev, &vc4_txp_ops);
+       return 0;
+}
+
+static const struct of_device_id vc4_txp_dt_match[] = {
+       { .compatible = "brcm,bcm2835-txp" },
+       { /* sentinel */ },
+};
+
+struct platform_driver vc4_txp_driver = {
+       .probe = vc4_txp_probe,
+       .remove = vc4_txp_remove,
+       .driver = {
+               .name = "vc4_txp",
+               .of_match_table = vc4_txp_dt_match,
+       },
+};