1 files changed, 305 insertions, 0 deletions
diff --git a/drivers/media/platform/vsp1/vsp1_dl.c b/drivers/media/platform/vsp1/vsp1_dl.c
new file mode 100644
index 000000000000..7dc27ac6bd02
--- /dev/null
+++ b/drivers/media/platform/vsp1/vsp1_dl.c
@@ -0,0 +1,305 @@
+/*
+ * vsp1_dl.h  --  R-Car VSP1 Display List
+ *
+ * Copyright (C) 2015 Renesas Corporation
+ *
+ * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/gfp.h>
+#include <linux/slab.h>
+
+#include "vsp1.h"
+#include "vsp1_dl.h"
+#include "vsp1_pipe.h"
+
+/*
+ * Global resources
+ *
+ * - Display-related interrupts (can be used for vblank evasion ?)
+ * - Display-list enable
+ * - Header-less for WPF0
+ * - DL swap
+ */
+
+#define VSP1_DL_BODY_SIZE		(2 * 4 * 256)
+#define VSP1_DL_NUM_LISTS		3
+
+struct vsp1_dl_entry {
+	u32 addr;
+	u32 data;
+} __attribute__((__packed__));
+
+struct vsp1_dl_list {
+	size_t size;
+	int reg_count;
+
+	bool in_use;
+
+	struct vsp1_dl_entry *body;
+	dma_addr_t dma;
+};
+
+/**
+ * struct vsp1_dl - Display List manager
+ * @vsp1: the VSP1 device
+ * @lock: protects the active, queued and pending lists
+ * @lists.all: array of all allocate display lists
+ * @lists.active: list currently being processed (loaded) by hardware
+ * @lists.queued: list queued to the hardware (written to the DL registers)
+ * @lists.pending: list waiting to be queued to the hardware
+ * @lists.write: list being written to by software
+ */
+struct vsp1_dl {
+	struct vsp1_device *vsp1;
+
+	spinlock_t lock;
+
+	size_t size;
+	dma_addr_t dma;
+	void *mem;
+
+	struct {
+		struct vsp1_dl_list all[VSP1_DL_NUM_LISTS];
+
+		struct vsp1_dl_list *active;
+		struct vsp1_dl_list *queued;
+		struct vsp1_dl_list *pending;
+		struct vsp1_dl_list *write;
+	} lists;
+};
+
+/* -----------------------------------------------------------------------------
+ * Display List Transaction Management
+ */
+
+static void vsp1_dl_free_list(struct vsp1_dl_list *list)
+{
+	if (!list)
+		return;
+
+	list->in_use = false;
+}
+
+void vsp1_dl_reset(struct vsp1_dl *dl)
+{
+	unsigned int i;
+
+	dl->lists.active = NULL;
+	dl->lists.queued = NULL;
+	dl->lists.pending = NULL;
+	dl->lists.write = NULL;
+
+	for (i = 0; i < ARRAY_SIZE(dl->lists.all); ++i)
+		dl->lists.all[i].in_use = false;
+}
+
+void vsp1_dl_begin(struct vsp1_dl *dl)
+{
+	struct vsp1_dl_list *list = NULL;
+	unsigned long flags;
+	unsigned int i;
+
+	spin_lock_irqsave(&dl->lock, flags);
+
+	for (i = 0; i < ARRAY_SIZE(dl->lists.all); ++i) {
+		if (!dl->lists.all[i].in_use) {
+			list = &dl->lists.all[i];
+			break;
+		}
+	}
+
+	if (!list) {
+		list = dl->lists.pending;
+		dl->lists.pending = NULL;
+	}
+
+	spin_unlock_irqrestore(&dl->lock, flags);
+
+	dl->lists.write = list;
+
+	list->in_use = true;
+	list->reg_count = 0;
+}
+
+void vsp1_dl_add(struct vsp1_entity *e, u32 reg, u32 data)
+{
+	struct vsp1_pipeline *pipe = to_vsp1_pipeline(&e->subdev.entity);
+	struct vsp1_dl *dl = pipe->dl;
+	struct vsp1_dl_list *list = dl->lists.write;
+
+	list->body[list->reg_count].addr = reg;
+	list->body[list->reg_count].data = data;
+	list->reg_count++;
+}
+
+void vsp1_dl_commit(struct vsp1_dl *dl)
+{
+	struct vsp1_device *vsp1 = dl->vsp1;
+	struct vsp1_dl_list *list;
+	unsigned long flags;
+	bool update;
+
+	list = dl->lists.write;
+	dl->lists.write = NULL;
+
+	spin_lock_irqsave(&dl->lock, flags);
+
+	/* Once the UPD bit has been set the hardware can start processing the
+	 * display list at any time and we can't touch the address and size
+	 * registers. In that case mark the update as pending, it will be
+	 * queued up to the hardware by the frame end interrupt handler.
+	 */
+	update = !!(vsp1_read(vsp1, VI6_DL_BODY_SIZE) & VI6_DL_BODY_SIZE_UPD);
+	if (update) {
+		vsp1_dl_free_list(dl->lists.pending);
+		dl->lists.pending = list;
+		goto done;
+	}
+
+	/* Program the hardware with the display list body address and size.
+	 * The UPD bit will be cleared by the device when the display list is
+	 * processed.
+	 */
+	vsp1_write(vsp1, VI6_DL_HDR_ADDR(0), list->dma);
+	vsp1_write(vsp1, VI6_DL_BODY_SIZE, VI6_DL_BODY_SIZE_UPD |
+		   (list->reg_count * 8));
+
+	vsp1_dl_free_list(dl->lists.queued);
+	dl->lists.queued = list;
+
+done:
+	spin_unlock_irqrestore(&dl->lock, flags);
+}
+
+/* -----------------------------------------------------------------------------
+ * Interrupt Handling
+ */
+
+void vsp1_dl_irq_display_start(struct vsp1_dl *dl)
+{
+	spin_lock(&dl->lock);
+
+	/* The display start interrupt signals the end of the display list
+	 * processing by the device. The active display list, if any, won't be
+	 * accessed anymore and can be reused.
+	 */
+	if (dl->lists.active) {
+		vsp1_dl_free_list(dl->lists.active);
+		dl->lists.active = NULL;
+	}
+
+	spin_unlock(&dl->lock);
+}
+
+void vsp1_dl_irq_frame_end(struct vsp1_dl *dl)
+{
+	struct vsp1_device *vsp1 = dl->vsp1;
+
+	spin_lock(&dl->lock);
+
+	/* The UPD bit set indicates that the commit operation raced with the
+	 * interrupt and occurred after the frame end event and UPD clear but
+	 * before interrupt processing. The hardware hasn't taken the update
+	 * into account yet, we'll thus skip one frame and retry.
+	 */
+	if (vsp1_read(vsp1, VI6_DL_BODY_SIZE) & VI6_DL_BODY_SIZE_UPD)
+		goto done;
+
+	/* The device starts processing the queued display list right after the
+	 * frame end interrupt. The display list thus becomes active.
+	 */
+	if (dl->lists.queued) {
+		WARN_ON(dl->lists.active);
+		dl->lists.active = dl->lists.queued;
+		dl->lists.queued = NULL;
+	}
+
+	/* Now that the UPD bit has been cleared we can queue the next display
+	 * list to the hardware if one has been prepared.
+	 */
+	if (dl->lists.pending) {
+		struct vsp1_dl_list *list = dl->lists.pending;
+
+		vsp1_write(vsp1, VI6_DL_HDR_ADDR(0), list->dma);
+		vsp1_write(vsp1, VI6_DL_BODY_SIZE, VI6_DL_BODY_SIZE_UPD |
+			   (list->reg_count * 8));
+
+		dl->lists.queued = list;
+		dl->lists.pending = NULL;
+	}
+
+done:
+	spin_unlock(&dl->lock);
+}
+
+/* -----------------------------------------------------------------------------
+ * Hardware Setup
+ */
+
+void vsp1_dl_setup(struct vsp1_device *vsp1)
+{
+	u32 ctrl = (256 << VI6_DL_CTRL_AR_WAIT_SHIFT)
+		 | VI6_DL_CTRL_DC2 | VI6_DL_CTRL_DC1 | VI6_DL_CTRL_DC0
+		 | VI6_DL_CTRL_DLE;
+
+	/* The DRM pipeline operates with header-less display lists in
+	 * Continuous Frame Mode.
+	 */
+	if (vsp1->drm)
+		ctrl |= VI6_DL_CTRL_CFM0 | VI6_DL_CTRL_NH0;
+
+	vsp1_write(vsp1, VI6_DL_CTRL, ctrl);
+	vsp1_write(vsp1, VI6_DL_SWAP, VI6_DL_SWAP_LWS);
+}
+
+/* -----------------------------------------------------------------------------
+ * Initialization and Cleanup
+ */
+
+struct vsp1_dl *vsp1_dl_create(struct vsp1_device *vsp1)
+{
+	struct vsp1_dl *dl;
+	unsigned int i;
+
+	dl = kzalloc(sizeof(*dl), GFP_KERNEL);
+	if (!dl)
+		return NULL;
+
+	spin_lock_init(&dl->lock);
+
+	dl->vsp1 = vsp1;
+	dl->size = VSP1_DL_BODY_SIZE * ARRAY_SIZE(dl->lists.all);
+
+	dl->mem = dma_alloc_writecombine(vsp1->dev, dl->size, &dl->dma,
+					 GFP_KERNEL);
+	if (!dl->mem) {
+		kfree(dl);
+		return NULL;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(dl->lists.all); ++i) {
+		struct vsp1_dl_list *list = &dl->lists.all[i];
+
+		list->size = VSP1_DL_BODY_SIZE;
+		list->reg_count = 0;
+		list->in_use = false;
+		list->dma = dl->dma + VSP1_DL_BODY_SIZE * i;
+		list->body = dl->mem + VSP1_DL_BODY_SIZE * i;
+	}
+
+	return dl;
+}
+
+void vsp1_dl_destroy(struct vsp1_dl *dl)
+{
+	dma_free_writecombine(dl->vsp1->dev, dl->size, dl->mem, dl->dma);
+	kfree(dl);
+}