1 files changed, 458 insertions, 0 deletions

diff --git a/drivers/media/platform/sunxi/sun4i-csi/sun4i_dma.c b/drivers/media/platform/sunxi/sun4i-csi/sun4i_dma.c
new file mode 100644
index 000000000..a3e826a75
--- /dev/null
+++ b/drivers/media/platform/sunxi/sun4i-csi/sun4i_dma.c
@@ -0,0 +1,458 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2016 NextThing Co
+ * Copyright (C) 2016-2019 Bootlin
+ *
+ * Author: Maxime Ripard <maxime.ripard@bootlin.com>
+ */
+
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+#include <media/videobuf2-dma-contig.h>
+#include <media/videobuf2-v4l2.h>
+
+#include "sun4i_csi.h"
+
+struct sun4i_csi_buffer {
+	struct vb2_v4l2_buffer	vb;
+	struct list_head	list;
+};
+
+static inline struct sun4i_csi_buffer *
+vb2_v4l2_to_csi_buffer(const struct vb2_v4l2_buffer *p)
+{
+	return container_of(p, struct sun4i_csi_buffer, vb);
+}
+
+static inline struct sun4i_csi_buffer *
+vb2_to_csi_buffer(const struct vb2_buffer *p)
+{
+	return vb2_v4l2_to_csi_buffer(to_vb2_v4l2_buffer(p));
+}
+
+static void sun4i_csi_capture_start(struct sun4i_csi *csi)
+{
+	writel(CSI_CPT_CTRL_VIDEO_START, csi->regs + CSI_CPT_CTRL_REG);
+}
+
+static void sun4i_csi_capture_stop(struct sun4i_csi *csi)
+{
+	writel(0, csi->regs + CSI_CPT_CTRL_REG);
+}
+
+static int sun4i_csi_queue_setup(struct vb2_queue *vq,
+				 unsigned int *nbuffers,
+				 unsigned int *nplanes,
+				 unsigned int sizes[],
+				 struct device *alloc_devs[])
+{
+	struct sun4i_csi *csi = vb2_get_drv_priv(vq);
+	unsigned int num_planes = csi->fmt.num_planes;
+	unsigned int i;
+
+	if (*nplanes) {
+		if (*nplanes != num_planes)
+			return -EINVAL;
+
+		for (i = 0; i < num_planes; i++)
+			if (sizes[i] < csi->fmt.plane_fmt[i].sizeimage)
+				return -EINVAL;
+		return 0;
+	}
+
+	*nplanes = num_planes;
+	for (i = 0; i < num_planes; i++)
+		sizes[i] = csi->fmt.plane_fmt[i].sizeimage;
+
+	return 0;
+};
+
+static int sun4i_csi_buffer_prepare(struct vb2_buffer *vb)
+{
+	struct sun4i_csi *csi = vb2_get_drv_priv(vb->vb2_queue);
+	unsigned int i;
+
+	for (i = 0; i < csi->fmt.num_planes; i++) {
+		unsigned long size = csi->fmt.plane_fmt[i].sizeimage;
+
+		if (vb2_plane_size(vb, i) < size) {
+			dev_err(csi->dev, "buffer too small (%lu < %lu)\n",
+				vb2_plane_size(vb, i), size);
+			return -EINVAL;
+		}
+
+		vb2_set_plane_payload(vb, i, size);
+	}
+
+	return 0;
+}
+
+static int sun4i_csi_setup_scratch_buffer(struct sun4i_csi *csi,
+					  unsigned int slot)
+{
+	dma_addr_t addr = csi->scratch.paddr;
+	unsigned int plane;
+
+	dev_dbg(csi->dev,
+		"No more available buffer, using the scratch buffer\n");
+
+	for (plane = 0; plane < csi->fmt.num_planes; plane++) {
+		writel(addr, csi->regs + CSI_BUF_ADDR_REG(plane, slot));
+		addr += csi->fmt.plane_fmt[plane].sizeimage;
+	}
+
+	csi->current_buf[slot] = NULL;
+	return 0;
+}
+
+static int sun4i_csi_buffer_fill_slot(struct sun4i_csi *csi, unsigned int slot)
+{
+	struct sun4i_csi_buffer *c_buf;
+	struct vb2_v4l2_buffer *v_buf;
+	unsigned int plane;
+
+	/*
+	 * We should never end up in a situation where we overwrite an
+	 * already filled slot.
+	 */
+	if (WARN_ON(csi->current_buf[slot]))
+		return -EINVAL;
+
+	if (list_empty(&csi->buf_list))
+		return sun4i_csi_setup_scratch_buffer(csi, slot);
+
+	c_buf = list_first_entry(&csi->buf_list, struct sun4i_csi_buffer, list);
+	list_del_init(&c_buf->list);
+
+	v_buf = &c_buf->vb;
+	csi->current_buf[slot] = v_buf;
+
+	for (plane = 0; plane < csi->fmt.num_planes; plane++) {
+		dma_addr_t buf_addr;
+
+		buf_addr = vb2_dma_contig_plane_dma_addr(&v_buf->vb2_buf,
+							 plane);
+		writel(buf_addr, csi->regs + CSI_BUF_ADDR_REG(plane, slot));
+	}
+
+	return 0;
+}
+
+static int sun4i_csi_buffer_fill_all(struct sun4i_csi *csi)
+{
+	unsigned int slot;
+	int ret;
+
+	for (slot = 0; slot < CSI_MAX_BUFFER; slot++) {
+		ret = sun4i_csi_buffer_fill_slot(csi, slot);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static void sun4i_csi_buffer_mark_done(struct sun4i_csi *csi,
+				       unsigned int slot,
+				       unsigned int sequence)
+{
+	struct vb2_v4l2_buffer *v_buf;
+
+	if (!csi->current_buf[slot]) {
+		dev_dbg(csi->dev, "Scratch buffer was used, ignoring..\n");
+		return;
+	}
+
+	v_buf = csi->current_buf[slot];
+	v_buf->field = csi->fmt.field;
+	v_buf->sequence = sequence;
+	v_buf->vb2_buf.timestamp = ktime_get_ns();
+	vb2_buffer_done(&v_buf->vb2_buf, VB2_BUF_STATE_DONE);
+
+	csi->current_buf[slot] = NULL;
+}
+
+static int sun4i_csi_buffer_flip(struct sun4i_csi *csi, unsigned int sequence)
+{
+	u32 reg = readl(csi->regs + CSI_BUF_CTRL_REG);
+	unsigned int next;
+
+	/* Our next buffer is not the current buffer */
+	next = !(reg & CSI_BUF_CTRL_DBS);
+
+	/* Report the previous buffer as done */
+	sun4i_csi_buffer_mark_done(csi, next, sequence);
+
+	/* Put a new buffer in there */
+	return sun4i_csi_buffer_fill_slot(csi, next);
+}
+
+static void sun4i_csi_buffer_queue(struct vb2_buffer *vb)
+{
+	struct sun4i_csi *csi = vb2_get_drv_priv(vb->vb2_queue);
+	struct sun4i_csi_buffer *buf = vb2_to_csi_buffer(vb);
+	unsigned long flags;
+
+	spin_lock_irqsave(&csi->qlock, flags);
+	list_add_tail(&buf->list, &csi->buf_list);
+	spin_unlock_irqrestore(&csi->qlock, flags);
+}
+
+static void return_all_buffers(struct sun4i_csi *csi,
+			       enum vb2_buffer_state state)
+{
+	struct sun4i_csi_buffer *buf, *node;
+	unsigned int slot;
+
+	list_for_each_entry_safe(buf, node, &csi->buf_list, list) {
+		vb2_buffer_done(&buf->vb.vb2_buf, state);
+		list_del(&buf->list);
+	}
+
+	for (slot = 0; slot < CSI_MAX_BUFFER; slot++) {
+		struct vb2_v4l2_buffer *v_buf = csi->current_buf[slot];
+
+		if (!v_buf)
+			continue;
+
+		vb2_buffer_done(&v_buf->vb2_buf, state);
+		csi->current_buf[slot] = NULL;
+	}
+}
+
+static int sun4i_csi_start_streaming(struct vb2_queue *vq, unsigned int count)
+{
+	struct sun4i_csi *csi = vb2_get_drv_priv(vq);
+	struct v4l2_mbus_config_parallel *bus = &csi->bus;
+	const struct sun4i_csi_format *csi_fmt;
+	unsigned long href_pol, pclk_pol, vref_pol;
+	unsigned long flags;
+	unsigned int i;
+	int ret;
+
+	csi_fmt = sun4i_csi_find_format(&csi->fmt.pixelformat, NULL);
+	if (!csi_fmt)
+		return -EINVAL;
+
+	dev_dbg(csi->dev, "Starting capture\n");
+
+	csi->sequence = 0;
+
+	/*
+	 * We need a scratch buffer in case where we'll not have any
+	 * more buffer queued so that we don't error out. One of those
+	 * cases is when you end up at the last frame to capture, you
+	 * don't havea any buffer queued any more, and yet it doesn't
+	 * really matter since you'll never reach the next buffer.
+	 *
+	 * Since we support the multi-planar API, we need to have a
+	 * buffer for each plane. Allocating a single one large enough
+	 * to hold all the buffers is simpler, so let's go for that.
+	 */
+	csi->scratch.size = 0;
+	for (i = 0; i < csi->fmt.num_planes; i++)
+		csi->scratch.size += csi->fmt.plane_fmt[i].sizeimage;
+
+	csi->scratch.vaddr = dma_alloc_coherent(csi->dev,
+						csi->scratch.size,
+						&csi->scratch.paddr,
+						GFP_KERNEL);
+	if (!csi->scratch.vaddr) {
+		dev_err(csi->dev, "Failed to allocate scratch buffer\n");
+		ret = -ENOMEM;
+		goto err_clear_dma_queue;
+	}
+
+	ret = video_device_pipeline_alloc_start(&csi->vdev);
+	if (ret < 0)
+		goto err_free_scratch_buffer;
+
+	spin_lock_irqsave(&csi->qlock, flags);
+
+	/* Setup timings */
+	writel(CSI_WIN_CTRL_W_ACTIVE(csi->fmt.width * 2),
+	       csi->regs + CSI_WIN_CTRL_W_REG);
+	writel(CSI_WIN_CTRL_H_ACTIVE(csi->fmt.height),
+	       csi->regs + CSI_WIN_CTRL_H_REG);
+
+	/*
+	 * This hardware uses [HV]REF instead of [HV]SYNC. Based on the
+	 * provided timing diagrams in the manual, positive polarity
+	 * equals active high [HV]REF.
+	 *
+	 * When the back porch is 0, [HV]REF is more or less equivalent
+	 * to [HV]SYNC inverted.
+	 */
+	href_pol = !!(bus->flags & V4L2_MBUS_HSYNC_ACTIVE_LOW);
+	vref_pol = !!(bus->flags & V4L2_MBUS_VSYNC_ACTIVE_LOW);
+	pclk_pol = !!(bus->flags & V4L2_MBUS_PCLK_SAMPLE_RISING);
+	writel(CSI_CFG_INPUT_FMT(csi_fmt->input) |
+	       CSI_CFG_OUTPUT_FMT(csi_fmt->output) |
+	       CSI_CFG_VREF_POL(vref_pol) |
+	       CSI_CFG_HREF_POL(href_pol) |
+	       CSI_CFG_PCLK_POL(pclk_pol),
+	       csi->regs + CSI_CFG_REG);
+
+	/* Setup buffer length */
+	writel(csi->fmt.plane_fmt[0].bytesperline,
+	       csi->regs + CSI_BUF_LEN_REG);
+
+	/* Prepare our buffers in hardware */
+	ret = sun4i_csi_buffer_fill_all(csi);
+	if (ret) {
+		spin_unlock_irqrestore(&csi->qlock, flags);
+		goto err_disable_pipeline;
+	}
+
+	/* Enable double buffering */
+	writel(CSI_BUF_CTRL_DBE, csi->regs + CSI_BUF_CTRL_REG);
+
+	/* Clear the pending interrupts */
+	writel(CSI_INT_FRM_DONE, csi->regs + 0x34);
+
+	/* Enable frame done interrupt */
+	writel(CSI_INT_FRM_DONE, csi->regs + CSI_INT_EN_REG);
+
+	sun4i_csi_capture_start(csi);
+
+	spin_unlock_irqrestore(&csi->qlock, flags);
+
+	ret = v4l2_subdev_call(csi->src_subdev, video, s_stream, 1);
+	if (ret < 0 && ret != -ENOIOCTLCMD)
+		goto err_disable_device;
+
+	return 0;
+
+err_disable_device:
+	sun4i_csi_capture_stop(csi);
+
+err_disable_pipeline:
+	video_device_pipeline_stop(&csi->vdev);
+
+err_free_scratch_buffer:
+	dma_free_coherent(csi->dev, csi->scratch.size, csi->scratch.vaddr,
+			  csi->scratch.paddr);
+
+err_clear_dma_queue:
+	spin_lock_irqsave(&csi->qlock, flags);
+	return_all_buffers(csi, VB2_BUF_STATE_QUEUED);
+	spin_unlock_irqrestore(&csi->qlock, flags);
+
+	return ret;
+}
+
+static void sun4i_csi_stop_streaming(struct vb2_queue *vq)
+{
+	struct sun4i_csi *csi = vb2_get_drv_priv(vq);
+	unsigned long flags;
+
+	dev_dbg(csi->dev, "Stopping capture\n");
+
+	v4l2_subdev_call(csi->src_subdev, video, s_stream, 0);
+	sun4i_csi_capture_stop(csi);
+
+	/* Release all active buffers */
+	spin_lock_irqsave(&csi->qlock, flags);
+	return_all_buffers(csi, VB2_BUF_STATE_ERROR);
+	spin_unlock_irqrestore(&csi->qlock, flags);
+
+	video_device_pipeline_stop(&csi->vdev);
+
+	dma_free_coherent(csi->dev, csi->scratch.size, csi->scratch.vaddr,
+			  csi->scratch.paddr);
+}
+
+static const struct vb2_ops sun4i_csi_qops = {
+	.queue_setup		= sun4i_csi_queue_setup,
+	.buf_prepare		= sun4i_csi_buffer_prepare,
+	.buf_queue		= sun4i_csi_buffer_queue,
+	.start_streaming	= sun4i_csi_start_streaming,
+	.stop_streaming		= sun4i_csi_stop_streaming,
+	.wait_prepare		= vb2_ops_wait_prepare,
+	.wait_finish		= vb2_ops_wait_finish,
+};
+
+static irqreturn_t sun4i_csi_irq(int irq, void *data)
+{
+	struct sun4i_csi *csi = data;
+	u32 reg;
+
+	reg = readl(csi->regs + CSI_INT_STA_REG);
+
+	/* Acknowledge the interrupts */
+	writel(reg, csi->regs + CSI_INT_STA_REG);
+
+	if (!(reg & CSI_INT_FRM_DONE))
+		return IRQ_HANDLED;
+
+	spin_lock(&csi->qlock);
+	if (sun4i_csi_buffer_flip(csi, csi->sequence++)) {
+		dev_warn(csi->dev, "%s: Flip failed\n", __func__);
+		sun4i_csi_capture_stop(csi);
+	}
+	spin_unlock(&csi->qlock);
+
+	return IRQ_HANDLED;
+}
+
+int sun4i_csi_dma_register(struct sun4i_csi *csi, int irq)
+{
+	struct vb2_queue *q = &csi->queue;
+	int ret;
+	int i;
+
+	spin_lock_init(&csi->qlock);
+	mutex_init(&csi->lock);
+
+	INIT_LIST_HEAD(&csi->buf_list);
+	for (i = 0; i < CSI_MAX_BUFFER; i++)
+		csi->current_buf[i] = NULL;
+
+	q->min_buffers_needed = 3;
+	q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+	q->io_modes = VB2_MMAP | VB2_DMABUF;
+	q->lock = &csi->lock;
+	q->drv_priv = csi;
+	q->buf_struct_size = sizeof(struct sun4i_csi_buffer);
+	q->ops = &sun4i_csi_qops;
+	q->mem_ops = &vb2_dma_contig_memops;
+	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+	q->dev = csi->dev;
+
+	ret = vb2_queue_init(q);
+	if (ret < 0) {
+		dev_err(csi->dev, "failed to initialize VB2 queue\n");
+		goto err_free_mutex;
+	}
+
+	ret = v4l2_device_register(csi->dev, &csi->v4l);
+	if (ret) {
+		dev_err(csi->dev, "Couldn't register the v4l2 device\n");
+		goto err_free_mutex;
+	}
+
+	ret = devm_request_irq(csi->dev, irq, sun4i_csi_irq, 0,
+			       dev_name(csi->dev), csi);
+	if (ret) {
+		dev_err(csi->dev, "Couldn't register our interrupt\n");
+		goto err_unregister_device;
+	}
+
+	return 0;
+
+err_unregister_device:
+	v4l2_device_unregister(&csi->v4l);
+
+err_free_mutex:
+	mutex_destroy(&csi->lock);
+	return ret;
+}
+
+void sun4i_csi_dma_unregister(struct sun4i_csi *csi)
+{
+	v4l2_device_unregister(&csi->v4l);
+	mutex_destroy(&csi->lock);
+}