buffer: Allocate DMA-BUFs via CMA where available

pull/118/merge
Andri Yngvason 2024-03-09 11:35:46 +00:00
parent 5b01551673
commit bd9daa85c3
1 changed files with 79 additions and 3 deletions

View File

@ -1,5 +1,5 @@
/*
* Copyright (c) 2020 - 2021 Andri Yngvason
* Copyright (c) 2020 - 2024 Andri Yngvason
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
@ -34,6 +34,12 @@
#ifdef ENABLE_SCREENCOPY_DMABUF
#include <gbm.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <linux/dma-buf.h>
#include <linux/dma-heap.h>
#define LINUX_CMA_PATH "/dev/dma_heap/linux,cma"
#endif
extern struct wl_shm* wl_shm;
@ -118,6 +124,74 @@ failure:
}
#ifdef ENABLE_SCREENCOPY_DMABUF
static bool have_linux_cma(void)
{
return access(LINUX_CMA_PATH, R_OK | W_OK) == 0;
}
static int linux_cma_alloc(size_t size)
{
int fd = open(LINUX_CMA_PATH, O_RDWR | O_CLOEXEC, 0);
if (fd < 0) {
nvnc_log(NVNC_LOG_ERROR, "Failed to open CMA device: %m");
return -1;
}
struct dma_heap_allocation_data data = {
.len = size,
.fd_flags = O_CLOEXEC | O_RDWR,
};
int r = ioctl(fd, DMA_HEAP_IOCTL_ALLOC, &data);
if (r < 0) {
nvnc_log(NVNC_LOG_ERROR, "Failed to allocate CMA buffer: %m");
return -1;
}
close(fd);
return data.fd;
}
// Some devices (mostly ARM SBCs) need CMA for hardware encoders.
static struct gbm_bo* create_cma_gbm_bo(int width, int height, uint32_t fourcc)
{
assert(gbm_device);
int bpp = pixel_size_from_fourcc(fourcc);
if (!bpp) {
nvnc_log(NVNC_LOG_PANIC, "Unsupported pixel format: %" PRIu32,
fourcc);
}
int stride = bpp * width;
int fd = linux_cma_alloc(stride * height);
if (fd < 0) {
return NULL;
}
struct gbm_import_fd_modifier_data d = {
.format = fourcc,
.width = width,
.height = height,
// v4l2m2m doesn't support modifiers, so we use linear
.modifier = DRM_FORMAT_MOD_LINEAR,
.num_fds = 1,
.fds[0] = fd,
.offsets[0] = 0,
.strides[0] = stride,
};
struct gbm_bo* bo = gbm_bo_import(gbm_device, GBM_BO_IMPORT_FD_MODIFIER,
&d, 0);
if (!bo) {
nvnc_log(NVNC_LOG_DEBUG, "Failed to import dmabuf: %m");
close(fd);
return NULL;
}
return bo;
}
static struct wv_buffer* wv_buffer_create_dmabuf(int width, int height,
uint32_t fourcc)
{
@ -133,7 +207,9 @@ static struct wv_buffer* wv_buffer_create_dmabuf(int width, int height,
self->height = height;
self->format = fourcc;
self->bo = gbm_bo_create(gbm_device, width, height, fourcc,
self->bo = have_linux_cma() ?
create_cma_gbm_bo(width, height, fourcc) :
gbm_bo_create(gbm_device, width, height, fourcc,
GBM_BO_USE_RENDERING);
if (!self->bo)
goto bo_failure;