v4l2-drm-example: dmabuf-sharing: version 0.1

1 files changed, 446 insertions, 0 deletions

diff --git a/v4l2-drm-example/dmabuf-sharing.c b/v4l2-drm-example/dmabuf-sharing.c
new file mode 100644
index 0000000..16bb082
--- /dev/null
+++ b/v4l2-drm-example/dmabuf-sharing.c
@@ -0,0 +1,446 @@
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/videodev2.h>
+#include <math.h>
+#include <poll.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <xf86drm.h>
+#include <xf86drmMode.h>
+#include <exynos_drm.h>
+
+#define ERRSTR strerror(errno)
+
+#define BYE_ON(cond, ...) \
+do { \
+	if (cond) { \
+		int errsv = errno; \
+		fprintf(stderr, "ERROR(%s:%d) : ", \
+			__FILE__, __LINE__); \
+		errno = errsv; \
+		fprintf(stderr,  __VA_ARGS__); \
+		abort(); \
+	} \
+} while(0)
+
+static inline int warn(const char *file, int line, const char *fmt, ...)
+{
+	int errsv = errno;
+	va_list va;
+	va_start(va, fmt);
+	fprintf(stderr, "WARN(%s:%d): ", file, line);
+	vfprintf(stderr, fmt, va);
+	va_end(va);
+	errno = errsv;
+	return 1;
+}
+
+#define WARN_ON(cond, ...) \
+	((cond) ? warn(__FILE__, __LINE__, __VA_ARGS__) : 0)
+
+struct setup {
+	char module[32];
+	uint32_t conId;
+	uint32_t crtId;
+	char modestr[32];
+	char video[32];
+	unsigned int w, h;
+	unsigned int use_wh : 1;
+	unsigned int in_fourcc;
+	unsigned int out_fourcc;
+	unsigned int buffer_count;
+	unsigned int use_crop : 1;
+	unsigned int use_compose : 1;
+	struct v4l2_rect crop;
+	struct v4l2_rect compose;
+};
+
+struct buffer {
+	unsigned int bo_handle;
+	unsigned int fb_handle;
+	int dbuf_fd;
+};
+
+struct stream {
+	int v4lfd;
+	int current_buffer;
+	int buffer_count;
+	struct buffer *buffer;
+} stream;
+
+static void usage(char *name)
+{
+	fprintf(stderr, "usage: %s [-Moisth]\n", name);
+	fprintf(stderr, "\t-M <drm-module>\tset DRM module\n");
+	fprintf(stderr, "\t-o <connector_id>:<crtc_id>:<mode>\tset a mode\n");
+	fprintf(stderr, "\t-i <video-node>\tset video node like /dev/video*\n");
+	fprintf(stderr, "\t-S <width,height>\tset input resolution\n");
+	fprintf(stderr, "\t-f <fourcc>\tset input format using 4cc\n");
+	fprintf(stderr, "\t-F <fourcc>\tset output format using 4cc\n");
+	fprintf(stderr, "\t-s <width,height>@<left,top>\tset crop area\n");
+	fprintf(stderr, "\t-t <width,height>@<left,top>\tset compose area\n");
+	fprintf(stderr, "\t-b buffer_count\tset number of buffers\n");
+	fprintf(stderr, "\t-h\tshow this help\n");
+	fprintf(stderr, "\n\tDefault is to dump all info.\n");
+}
+
+static inline int parse_rect(char *s, struct v4l2_rect *r)
+{
+	return sscanf(s, "%d,%d@%d,%d", &r->width, &r->height,
+		&r->top, &r->left) != 4;
+}
+
+static int parse_args(int argc, char *argv[], struct setup *s)
+{
+	if (argc <= 1)
+		usage(argv[0]);
+
+	int c, ret;
+	memset(s, 0, sizeof(*s));
+
+	while ((c = getopt(argc, argv, "M:o:i:S:f:F:s:t:b:h")) != -1) {
+		switch (c) {
+		case 'M':
+			strncpy(s->module, optarg, 31);
+			break;
+		case 'o':
+			ret = sscanf(optarg, "%u:%u:%31s", &s->conId, &s->crtId,
+				s->modestr);
+			if (WARN_ON(ret != 3, "incorrect mode description\n"))
+				return -1;
+			break;
+		case 'i':
+			strncpy(s->video, optarg, 31);
+			break;
+		case 'S':
+			ret = sscanf(optarg, "%u,%u", &s->w, &s->h);
+			if (WARN_ON(ret != 2, "incorrect input size\n"))
+				return -1;
+			s->use_wh = 1;
+			break;
+		case 'f':
+			if (WARN_ON(strlen(optarg) != 4, "invalid fourcc\n"))
+				return -1;
+			s->in_fourcc = ((unsigned)optarg[0] << 0) |
+				((unsigned)optarg[1] << 8) |
+				((unsigned)optarg[2] << 16) |
+				((unsigned)optarg[3] << 24);
+			break;
+		case 'F':
+			if (WARN_ON(strlen(optarg) != 4, "invalid fourcc\n"))
+				return -1;
+			s->out_fourcc = ((unsigned)optarg[0] << 0) |
+				((unsigned)optarg[1] << 8) |
+				((unsigned)optarg[2] << 16) |
+				((unsigned)optarg[3] << 24);
+			break;
+		case 's':
+			ret = parse_rect(optarg, &s->crop);
+			if (WARN_ON(ret, "incorrect crop area\n"))
+				return -1;
+			s->use_crop = 1;
+			break;
+		case 't':
+			ret = parse_rect(optarg, &s->compose);
+			if (WARN_ON(ret, "incorrect compose area\n"))
+				return -1;
+			s->use_compose = 1;
+			break;
+		case 'b':
+			ret = sscanf(optarg, "%u", &s->buffer_count);
+			if (WARN_ON(ret != 1, "incorrect buffer count\n"))
+				return -1;
+			break;
+		case '?':
+		case 'h':
+			usage(argv[0]);
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int buffer_create(struct buffer *b, int drmfd, struct setup *s,
+	uint64_t size, uint32_t pitch)
+{
+	int ret = strncmp(s->module, "exynos", 6);
+	if (WARN_ON(ret, "drm: only exynos GEM is supported\n"))
+		return -1;
+
+	struct drm_exynos_gem_create gem;
+	struct drm_gem_close gem_close;
+
+	memset(&gem, 0, sizeof gem);
+	gem.size = size;
+	ret = ioctl(drmfd, DRM_IOCTL_EXYNOS_GEM_CREATE, &gem);
+	if (WARN_ON(ret, "EXYNOS_GEM_CREATE failed: %s\n", ERRSTR))
+		return -1;
+	b->bo_handle = gem.handle;
+
+	struct drm_prime_handle prime;
+	memset(&prime, 0, sizeof prime);
+	prime.handle = b->bo_handle;
+
+	ret = ioctl(drmfd, DRM_IOCTL_PRIME_HANDLE_TO_FD, &prime);
+	if (WARN_ON(ret, "PRIME_HANDLE_TO_FD failed: %s\n", ERRSTR))
+		goto fail_gem;
+	printf("dbuf_fd = %d\n", prime.fd);
+	b->dbuf_fd = prime.fd;
+
+	uint32_t offsets[4] = { 0 };
+	uint32_t pitches[4] = { pitch };
+	uint32_t bo_handles[4] = { b->bo_handle };
+	unsigned int fourcc = s->out_fourcc;
+	if (!fourcc)
+		fourcc = s->in_fourcc;
+	ret = drmModeAddFB2(drmfd, s->w, s->h, fourcc, bo_handles,
+		pitches, offsets, &b->fb_handle, 0);
+	if (WARN_ON(ret, "drmModeAddFB2 failed: %s\n", ERRSTR))
+		goto fail_prime;
+
+	return 0;
+
+fail_prime:
+	close(b->dbuf_fd);
+
+fail_gem:
+	memset(&gem_close, 0, sizeof gem_close);
+	gem_close.handle = b->bo_handle,
+	ret = ioctl(drmfd, DRM_IOCTL_GEM_CLOSE, gem_close);
+	WARN_ON(ret, "GEM_CLOSE failed: %s\n", ERRSTR);
+
+	return -1;
+}
+
+static int find_mode(drmModeModeInfo *m, int drmfd, struct setup *s,
+	uint32_t *con)
+{
+	int ret = -1;
+	drmModeRes *res = drmModeGetResources(drmfd);
+	if (WARN_ON(!res, "drmModeGetResources failed: %s\n", ERRSTR))
+		return -1;
+
+	if (WARN_ON(res->count_crtcs <= 0, "drm: no crts\n"))
+		goto fail_res;
+
+	if (WARN_ON(res->count_connectors <= 0, "drm: no connectors\n"))
+		goto fail_res;
+
+	if (WARN_ON(s->conId >= res->count_connectors, "connector %d "
+		"is not supported\n", s->conId))
+		goto fail_res;
+
+	drmModeConnector *c;
+	c = drmModeGetConnector(drmfd, res->connectors[s->conId]);
+
+	if (WARN_ON(!c, "drmModeGetConnector failed: %s\n", ERRSTR))
+		goto fail_res;
+
+	if (WARN_ON(!c->count_modes, "connector supports no mode\n"))
+		goto fail_conn;
+
+	drmModeModeInfo *found = NULL;
+	for (int i = 0; i < c->count_modes; ++i)
+		if (strcmp(c->modes[i].name, s->modestr) == 0)
+			found = &c->modes[i];
+
+	if (WARN_ON(!found, "mode %s not supported\n", s->modestr)) {
+		fprintf(stderr, "Valid modes:");
+		for (int i = 0; i < c->count_modes; ++i)
+			fprintf(stderr, " %s", c->modes[i].name);
+		fprintf(stderr, "\n");
+		goto fail_conn;
+	}
+
+	memcpy(m, found, sizeof *found);
+	if (con)
+		*con = c->connector_id;
+	ret = 0;
+
+fail_conn:
+	drmModeFreeConnector(c);
+
+fail_res:
+	drmModeFreeResources(res);
+
+	return ret;
+}
+
+static void page_flip_handler(int fd, unsigned int frame,
+	unsigned int sec, unsigned int usec, void *data)
+{
+	int index = stream.current_buffer;
+	struct v4l2_buffer buf;
+	int ret;
+
+	stream.current_buffer = (int)data;
+	if (index < 0)
+		return;
+
+	memset(&buf, 0, sizeof buf);
+	buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	buf.memory = V4L2_MEMORY_DMABUF;
+	buf.index = index;
+	buf.m.fd = stream.buffer[index].dbuf_fd;
+
+	ret = ioctl(stream.v4lfd, VIDIOC_QBUF, &buf);
+	BYE_ON(ret, "VIDIOC_QBUF(index = %d) failed: %s\n", index, ERRSTR);
+}
+
+int main(int argc, char *argv[])
+{
+	int ret;
+	struct setup s;
+
+	ret = parse_args(argc, argv, &s);
+	BYE_ON(ret, "failed to parse arguments\n");
+	BYE_ON(s.module[0] == 0, "DRM module is missing\n");
+	BYE_ON(s.video[0] == 0, "video node is missing\n");
+
+	int drmfd = drmOpen(s.module, NULL);
+	BYE_ON(drmfd < 0, "drmOpen(%s) failed: %s\n", s.module, ERRSTR);
+
+	int v4lfd = open(s.video, O_RDWR);
+	BYE_ON(v4lfd < 0, "failed to open %s: %s\n", s.video, ERRSTR);
+
+	struct v4l2_capability caps;
+	memset(&caps, 0, sizeof caps);
+
+	ret = ioctl(v4lfd, VIDIOC_QUERYCAP, &caps);
+	BYE_ON(ret, "VIDIOC_QUERYCAP failed: %s\n", ERRSTR);
+
+	/* TODO: add single plane support */
+	BYE_ON(~caps.capabilities & V4L2_CAP_VIDEO_CAPTURE,
+		"video: singleplanar capture is not supported\n");
+
+	struct v4l2_format fmt;
+	memset(&fmt, 0, sizeof fmt);
+	fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+
+	ret = ioctl(v4lfd, VIDIOC_G_FMT, &fmt);
+	BYE_ON(ret < 0, "VIDIOC_G_FMT failed: %s\n", ERRSTR);
+	printf("G_FMT(start): width = %u, height = %u, 4cc = %.4s\n",
+		fmt.fmt.pix.width, fmt.fmt.pix.height,
+		(char*)&fmt.fmt.pix.pixelformat);
+
+	if (s.use_wh) {
+		fmt.fmt.pix.width = s.w;
+		fmt.fmt.pix.height = s.h;
+	}
+	if (s.in_fourcc)
+		fmt.fmt.pix.pixelformat = s.in_fourcc;
+
+	ret = ioctl(v4lfd, VIDIOC_S_FMT, &fmt);
+	BYE_ON(ret < 0, "VIDIOC_S_FMT failed: %s\n", ERRSTR);
+
+	ret = ioctl(v4lfd, VIDIOC_G_FMT, &fmt);
+	BYE_ON(ret < 0, "VIDIOC_G_FMT failed: %s\n", ERRSTR);
+	printf("G_FMT(final): width = %u, height = %u, 4cc = %.4s\n",
+		fmt.fmt.pix.width, fmt.fmt.pix.height,
+		(char*)&fmt.fmt.pix.pixelformat);
+
+	struct v4l2_requestbuffers rqbufs;
+	memset(&rqbufs, 0, sizeof(rqbufs));
+	rqbufs.count = s.buffer_count;
+	rqbufs.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	rqbufs.memory = V4L2_MEMORY_DMABUF;
+
+	ret = ioctl(v4lfd, VIDIOC_REQBUFS, &rqbufs);
+	BYE_ON(ret < 0, "VIDIOC_REQBUFS failed: %s\n", ERRSTR);
+	BYE_ON(rqbufs.count < s.buffer_count, "video node allocated only "
+		"%u of %u buffers\n", rqbufs.count, s.buffer_count);
+
+	s.in_fourcc = fmt.fmt.pix.pixelformat;
+	s.w = fmt.fmt.pix.width;
+	s.h = fmt.fmt.pix.height;
+
+	/* TODO: add support for multiplanar formats */
+	struct buffer buffer[s.buffer_count];
+	uint64_t size = fmt.fmt.pix.sizeimage;
+	uint32_t pitch = fmt.fmt.pix.bytesperline;
+	printf("size = %llu pitch = %u\n", size, pitch);
+	for (int i = 0; i < s.buffer_count; ++i) {
+		ret = buffer_create(&buffer[i], drmfd, &s, size, pitch);
+		BYE_ON(ret, "failed to create buffer%d\n", i);
+	}
+	printf("buffers ready\n");
+
+	drmModeModeInfo drmmode;
+	uint32_t con;
+	ret = find_mode(&drmmode, drmfd, &s, &con);
+	BYE_ON(ret, "failed to find valid mode\n");
+
+	ret = drmModeSetCrtc(drmfd, s.crtId, buffer[0].fb_handle, 0, 0,
+		&con, 1, &drmmode);
+	BYE_ON(ret, "drmModeSetCrtc failed: %s\n", ERRSTR);
+
+	/* enqueueing first buffer to DRM */
+	ret = drmModePageFlip(drmfd, s.crtId, buffer[0].fb_handle,
+		DRM_MODE_PAGE_FLIP_EVENT, 0);
+	BYE_ON(ret, "drmModePageFlip failed: %s\n", ERRSTR);
+
+	for (int i = 1; i < s.buffer_count; ++i) {
+		struct v4l2_buffer buf;
+		memset(&buf, 0, sizeof buf);
+
+		buf.index = i;
+		buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+		buf.memory = V4L2_MEMORY_DMABUF;
+		buf.m.fd = buffer[i].dbuf_fd;
+		ret = ioctl(v4lfd, VIDIOC_QBUF, &buf);
+		BYE_ON(ret < 0, "VIDIOC_QBUF for buffer %d failed: %s\n",
+			buf.index, ERRSTR);
+	}
+
+	int type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	ret = ioctl(v4lfd, VIDIOC_STREAMON, &type);
+	BYE_ON(ret < 0, "STREAMON failed: %s\n", ERRSTR);
+
+	struct pollfd fds[] = {
+		{ .fd = v4lfd, .events = POLLIN },
+		{ .fd = drmfd, .events = POLLIN },
+	};
+
+	/* buffer currently used by drm */
+	stream.v4lfd = v4lfd;
+	stream.current_buffer = -1;
+	stream.buffer = buffer;
+
+	while ((ret = poll(fds, 2, 5000)) > 0) {
+		if (fds[0].revents & POLLIN) {
+			struct v4l2_buffer buf;
+			memset(&buf, 0, sizeof buf);
+			/* dequeue buffer */
+			buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+			buf.memory = V4L2_MEMORY_DMABUF;
+			ret = ioctl(v4lfd, VIDIOC_DQBUF, &buf);
+			BYE_ON(ret, "VIDIOC_DQBUF failed: %s\n", ERRSTR);
+
+			ret = drmModePageFlip(drmfd, s.crtId, buffer[buf.index].fb_handle,
+				DRM_MODE_PAGE_FLIP_EVENT, (void*)buf.index);
+			BYE_ON(ret, "drmModePageFlip failed: %s\n", ERRSTR);
+
+		}
+		if (fds[1].revents & POLLIN) {
+			drmEventContext evctx;
+			memset(&evctx, 0, sizeof evctx);
+			evctx.version = DRM_EVENT_CONTEXT_VERSION;
+			evctx.page_flip_handler = page_flip_handler;
+
+			ret = drmHandleEvent(drmfd, &evctx);
+			BYE_ON(ret, "drmHandleEvent failed: %s\n", ERRSTR);
+		}
+	}
+
+	return 0;
+}
+