Support Linux DRM backend #69
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What compatibility risks exist when using DRM legacy interfaces with newer Linux kernels? Could you verify the compatibility status of libdrm across different kernel versions? What prevents the DRM backend from rendering content across the full screen resolution? |
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@a1091150, You might check DRM backend for your environment as well. |
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| return true; | ||
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| bail_crtc: |
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I'm confused about this. It should be as below.
/* Retrieve resources */
if (!get_resources(tx->drm_dri_fd, &RES(tx)))
goto bail_res;
....
bail_fb:
drmModeRmFB(tx->drm_dri_fd, tx->fb_id);
munmap(tx->fb_base, tx->fb_len);
bail_crtc:
drmModeFreeCrtc(CRTC(tx));
bail_conn:
drmModeFreeConnector(CONN(tx));
bail_res:
drmModeFreeResources(RES(tx));
Implemented DRM-based framebuffer setup, including: - Opening DRM device - Creating dumb buffers and mapping them to framebuffers - Setting mode and handling CRTC for connected display output Currently, using the DRM legacy interface is suitable for Mado's backend if we only need basic window display without advanced features. The DRM legacy is simpler to implement. Close sysprog21#60
| @@ -83,6 +83,9 @@ For SDL backend, install the [SDL2 library](https://www.libsdl.org/). | |||
| * macOS: `brew install sdl2` | |||
| * Ubuntu Linux / Debian: `sudo apt install libsdl2-dev` | |||
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| For DRM backend, install the [libdrm](https://cgit.freedesktop.org/mesa/drm/). | |||
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Change the hyperlink to https://gitlab.freedesktop.org/mesa/drm
| @@ -0,0 +1,24 @@ | |||
| /* | |||
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Decouple linux VT changes in another pull request which adapts fbdev backend as well. That is, the linux VT routines should be shared between fbdev and DRM backends.
I need more time to research and adjust. |
| return false; | ||
| } | ||
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| /* Virtual terminal part is same as fbdev */ |
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Decouple this to another pull request to share the Linux VT manipulation.
| { | ||
| *resources = drmModeGetResources(fd); | ||
| if (*resources == NULL) { | ||
| log_error("drmModeGetResources failed"); |
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Make the error messages consistent, starting with "Failed to ..."
| @@ -12,6 +12,10 @@ config BACKEND_FBDEV | |||
| bool "Linux framebuffer support" | |||
| select CURSOR | |||
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| config BACKEND_DRM | |||
| bool "DRM support" | |||
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Consider changing to Linux DRM support for avoiding confusion.
| uint32_t fb_id; | ||
| uint32_t *fb_base; | ||
| size_t fb_len; | ||
| // int display_width; |
| twin_coord_t width = right - left; | ||
| int line_length = 4 * tx->width; | ||
| off_t off = line_length * top + 4 * left; | ||
| unsigned char *dest = (unsigned char *) tx->fb_base + off; |
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Replace unsigned char with uint8_t for consistency and use uintptr_t for pointer arithmetic. That is:
uint8_t *dest = (uint8_t *)((uintptr_t) tx->fb_base + off);| return NULL; | ||
| } | ||
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Remove one empty line here.
| free(ctx->priv); | ||
| free(ctx); | ||
| } | ||
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Check the DRM implementation for reference: https://github.com/zlgopen/awtk-linux-fb/blob/master/awtk-port/lcd_linux/lcd_linux_drm.c |
Currently, using the DRM legacy interface is suitable for Mado's backend because we only need basic window display without advanced features.