7 Dec
2015
7 Dec
'15
3:02 p.m.
On Fri, Dec 04, 2015 at 09:46:07AM +0100, Daniel Vetter wrote: [...]
diff --git a/include/drm/drm_modes.h b/include/drm/drm_modes.h
[...]
@@ -96,17 +141,124 @@ enum drm_mode_status {
#define DRM_MODE_FLAG_3D_MAX DRM_MODE_FLAG_3D_SIDE_BY_SIDE_HALF
+/**
- struct drm_display_mode - DRM kernel-internal display mode structure
[...]
- @crtc_hdisplay: hardware modehorizontal display size
- @crtc_hsync_start: hardware modehorizontal sync start
- @crtc_hsync_end: hardware modehorizontal sync end
- @crtc_htotal: hardware modehorizontal total size
- @crtc_hskew: hardware modehorizontal skew?!
- @crtc_vdisplay: hardware modevertical display size
- @crtc_vsync_start: hardware modevertical sync start
- @crtc_vsync_end: hardware modevertical sync end
- @crtc_vtotal: hardware modevertical total size
- @crtc_vscan: hardware modevertical scan?!
These are missing a space between "mode" and the description.
- The horizontal an vertical timings are defined per the following diagram:
Active Front Sync Back
Region Porch Porch
<-----------------------><----------------><-------------><-------------->
//////////////////////|
////////////////////// |
////////////////////// |.................. ................
_______________
<----- [hv]display ----->
<------------- [hv]sync_start ------------>
<--------------------- [hv]sync_end --------------------->
<-------------------------------- [hv]total ----------------------------->*
- This structure contains two copies of timings. First are the plain timings,
- which specify the logical mode, as it would be for a progressive 1:1 scanout
- at the refresh rate userspace can observe through vblank timestamps. Then
- there's the hardware timings, which are corrected for interlacing,
- double-clocking and similar things. They are provided as a convience, and can
"convenience"
- be appropriately computed using drm_mode_set_crtcinfo().
- */
struct drm_display_mode {
- /* Header */
- /**
* @head:** struct list_head for mode lists.*/- /**
* @base:** A display mode is a normal modeset object, possibly including public* userspace id.** FIXME:** This can probably be removed since the entire concept of userspace* managing modes explicitly hasn't ever landed in upstream kernel mode
"has never"
* setting support.*/struct drm_mode_object base;
/**
* @name:** Human-readable name of the mode, filled out with drm_mode_set_name().*/char name[DRM_DISPLAY_MODE_LEN];
/**
* @status:** Status of the mode, used to filter out modes not supported by the* hardware. See enum &drm_mode_status.*/enum drm_mode_status status;
/**
* @type:** A bitmask of flags, mostly about the source of a mode. Possible flags* are:** - DRM_MODE_TYPE_BUILTIN: Meant for hard-coded modes, effectively* unused.* - DRM_MODE_TYPE_PREFERRED: Preferred mode, usually the native* resolution of an LCD panel. There should only be one preferred* mode per connector at any given time.* - DRM_MODE_TYPE_DRIVER: Mode created by the driver, which is all of* them really. Drivers must set this bit for all modes they create* and expose to userspace.** Plus a big list of flags which shouldn't be used at all, but are* still around since these flags are also used in the userspace ABI:** - DRM_MODE_TYPE_DEFAULT: Again a leftover, use* DRM_MODE_TYPE_PREFERRED instead.* - DRM_MODE_TYPE_CLOCK_C and DRM_MODE_TYPE_CRTC_C: Define leftovers* which are stuck around for hysterical raisins only. No one has an* idea what they where meant for. Don't use.
"were"
* - DRM_MODE_TYPE_USERDEF: Mode defined by userspace, again a vestige* from older kms designs where userspace had to first add a custom* mode to the kernel's mode list before it could use it. Don't use.*/
- /* Proposed mode values */
- /**
* @clock:** Pixel clock in kHz.*/@@ -118,14 +270,74 @@ struct drm_display_mode { int vsync_end; int vtotal; int vscan;
I'm thinking that these could all use "unsigned", but that's definitely something for a separate patch.
- /**
* @flags:** Sync and timing flags:** - DRM_MODE_FLAG_PHSYNC: horizontal sync is active high.* - DRM_MODE_FLAG_NHSYNC: horizontal sync is active low.* - DRM_MODE_FLAG_PVSYNC: vertical sync is active high.* - DRM_MODE_FLAG_NVSYNC: vertical sync is active low.* - DRM_MODE_FLAG_INTERLACE: mode is interlaced.* - DRM_MODE_FLAG_DBLSCAN: mode uses doublescan.* - DRM_MODE_FLAG_CSYNC: mode uses composite sync.* - DRM_MODE_FLAG_PCSYNC: composite sync is active high.* - DRM_MODE_FLAG_NCSYNC: composite sync is active low.* - DRM_MODE_FLAG_HSKEW: hskew provided (not used?).* - DRM_MODE_FLAG_BCAST: not used?* - DRM_MODE_FLAG_PIXMUX: not used?* - DRM_MODE_FLAG_DBLCLK: double-clocked mode.* - DRM_MODE_FLAG_CLKDIV2: half-clocked mode.** Additionally there's flags to specify how 3D modes are packed:** - DRM_MODE_FLAG_3D_NONE: normal, non-3D mode.* - DRM_MODE_FLAG_3D_FRAME_PACKING: 2 full frames for left and right.* - DRM_MODE_FLAG_3D_FIELD_ALTERNATIVE: interleaved like fields.* - DRM_MODE_FLAG_3D_LINE_ALTERNATIVE: interleaved lines.* - DRM_MODE_FLAG_3D_SIDE_BY_SIDE_FULL: side-by-side full frames.* - DRM_MODE_FLAG_3D_L_DEPTH: ?
^
Stray tab.
* Note that with digital outputs like HDMI or DP there's usually a* massive confusion between the dot clock and the signal clock at the* bit encoding level. Especially when a 8b/10b encoding is used and the* differences is exactly a factor of 10.
"difference"
*/- int crtc_clock; int crtc_hdisplay; int crtc_hblank_start; int crtc_hblank_end;
@@ -140,12 +352,48 @@ struct drm_display_mode { int crtc_vsync_end; int crtc_vtotal;
- /* Driver private mode info */
- /**
* @private:** Pointer for driver private data. This can only be used for mode* objects passed to drivers in modeset operations. It shouldn't be used* by atomic drivers since they can store any additional data by* subclassing state structures.*/
Off-topic: Any reasons why this is int * and not void *?
- /**
* @private_flags:** Similar to @private, but just an integer.*/
- int vrefresh; /* in Hz */
- int hsync; /* in kHz */
- /**
* @vrefresh:** Vertical refresh rate, for debug output in human readable form. Not* used in a functional way.** This value is in Hz.*/- int vrefresh;
- /**
* @hsync:** Horizontal refresh rate, for debug output in human readable form. Not* used in a functional way.** This value is in kHz.*/- int hsync;
- /**
* @picture_aspect_ratio:** Filed for setting the HDMI picture aspect ratio of a mode.
"Field".
Thierry