wlroots-hyprland/include/backend/drm/util.h
Simon Ser 5dfaf5ea9c backend/drm: introduce wlr_drm_bo_handle_table
Using GBM to import DRM dumb buffers tends to not work well. By
using GBM we're calling some driver-specific functions in Mesa.
These functions check whether Mesa can work with the buffer.
Sometimes Mesa has requirements which differ from DRM dumb buffers
and the GBM import will fail (e.g. on amdgpu).

Instead, drop GBM and use drmPrimeFDToHandle directly. But there's
a twist: BO handles are not ref'counted by the kernel and need to
be ref'counted in user-space [1]. libdrm usually performs this
bookkeeping and is used under-the-hood by Mesa.

We can't re-use libdrm for this task without using driver-specific
APIs. So let's just re-implement the ref'counting logic in wlroots.
The wlroots implementation is inspired from amdgpu's in libdrm [2].

Closes: https://github.com/swaywm/wlroots/issues/2916

[1]: https://gitlab.freedesktop.org/mesa/drm/-/merge_requests/110
[2]: 1a4c0ec9ae/amdgpu/handle_table.c
2021-08-25 10:05:37 -04:00

39 lines
1.2 KiB
C

#ifndef BACKEND_DRM_UTIL_H
#define BACKEND_DRM_UTIL_H
#include <stdint.h>
#include <wlr/types/wlr_output.h>
#include <xf86drm.h>
#include <xf86drmMode.h>
// Calculates a more accurate refresh rate (mHz) than what mode itself provides
int32_t calculate_refresh_rate(const drmModeModeInfo *mode);
// Populates the make/model/phys_{width,height} of output from the edid data
void parse_edid(struct wlr_output *restrict output, size_t len,
const uint8_t *data);
// Returns the string representation of a DRM output type
const char *conn_get_name(uint32_t type_id);
// Part of match_obj
enum {
UNMATCHED = (uint32_t)-1,
SKIP = (uint32_t)-2,
};
/*
* Tries to match some DRM objects with some other DRM resource.
* e.g. Match CRTCs with Encoders, CRTCs with Planes.
*
* objs contains a bit array which resources it can be matched with.
* e.g. Bit 0 set means can be matched with res[0]
*
* res contains an index of which objs it is matched with or UNMATCHED.
*
* This solution is left in out.
* Returns the total number of matched solutions.
*/
size_t match_obj(size_t num_objs, const uint32_t objs[static restrict num_objs],
size_t num_res, const uint32_t res[static restrict num_res],
uint32_t out[static restrict num_res]);
#endif