Test application for DMABUF sharing between V4L2 and DRM

Kyungmin Park kmpark at infradead.org
Wed Apr 11 01:21:20 PDT 2012


Hi Tomasz,

How about to add this program to tools directory? tools/drm or tools/media?

Thank you,
Kyungmin Park

On Wed, Apr 11, 2012 at 1:13 AM, Tomasz Stanislawski
<t.stanislaws at samsung.com> wrote:
> Hi Everyone,
> This email contains a test application showing DMABUF sharing
> between DRM/KMS display and capture node including VIVI.
> It shows a simple preview on LCD display. The similar application
> was posted in thread:
> http://thread.gmane.org/gmane.comp.video.dri.devel/65997
>
> This version makes use of single-plane API for V4L2 capture instead
> of multiplanar. This change allows VIVI driver to be tested as
> DMABUF importer.
>
> The program is written in C99 and it was tested using Exynos/DRM
> and VIVI capture.
>
> This application shows how buffer sharing between V4L2/DRM may look like.
> Please let me know if/where I use DRM/V4L2 incorrectly.
>
> The application was tested against 3.4-rc1 kernel with patches:
>
> - Integration of videobuf2 with dmabuf
> http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/46586
>
> - Integration of vb2-vmalloc and VIVI with dmabuf
> http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/46713
>
> - Support for DRM prime for Exynos by Inki Dae
> http://git.infradead.org/users/kmpark/linux-2.6-samsung/shortlog/refs/heads/exynos-drm-prime
>
> - patch fixing kmap/vmap support for EXYNOS-DRM prime.
> http://git.infradead.org/users/kmpark/linux-2.6-samsung/commit/3c483f24e418f342eac40dc5fb3991e058deb270
>
>
> The branch containing all mentioned patches (without platform code)
> rebased on 3.4-rc1 is available at link:
>
> http://git.infradead.org/users/kmpark/linux-2.6-samsung/shortlog/refs/heads/v3.4-rc1-v4l-drm-dmabuf-for-test
>
> Regards,
> Tomasz Stanislawski
>
> ---
>
>
> #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;
> }
>
>
>
>
>
>
>
>
>
>
> --
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