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Diffstat (limited to 'packages/linux/linux-omap/0003-DSS-Documentation-for-OMAP2-3-display-subsystem.patch')
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diff --git a/packages/linux/linux-omap/0003-DSS-Documentation-for-OMAP2-3-display-subsystem.patch b/packages/linux/linux-omap/0003-DSS-Documentation-for-OMAP2-3-display-subsystem.patch deleted file mode 100644 index c3dba570d6..0000000000 --- a/packages/linux/linux-omap/0003-DSS-Documentation-for-OMAP2-3-display-subsystem.patch +++ /dev/null @@ -1,259 +0,0 @@ -From 66fad2b53d3427962407b40af79e227635aed780 Mon Sep 17 00:00:00 2001 -From: Tomi Valkeinen <tomi.valkeinen@nokia.com> -Date: Tue, 4 Nov 2008 15:08:07 +0200 -Subject: [PATCH] DSS: Documentation for OMAP2/3 display subsystem - -Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com> ---- - Documentation/arm/OMAP/DSS | 239 ++++++++++++++++++++++++++++++++++++++++++++ - 1 files changed, 239 insertions(+), 0 deletions(-) - create mode 100644 Documentation/arm/OMAP/DSS - -diff --git a/Documentation/arm/OMAP/DSS b/Documentation/arm/OMAP/DSS -new file mode 100644 -index 0000000..387bb73 ---- /dev/null -+++ b/Documentation/arm/OMAP/DSS -@@ -0,0 +1,239 @@ -+OMAP2/3 Display Subsystem -+------------------------- -+ -+This is an almost total rewrite of the OMAP FB driver in drivers/video/omap -+(let's call it DSS1). The main differences between DSS1 and DSS2 are DSI, -+TV-out and multiple display support. -+ -+The DSS2 driver (omap-dss module) is in arch/arm/plat-omap/dss/, and the FB, -+panel and controller drivers are in drivers/video/omap2/. DSS1 and DSS2 live -+currently side by side, you can choose which one to use. -+ -+Features -+-------- -+ -+Working and tested features include: -+ -+- MIPI DPI (parallel) output -+- MIPI DSI output in command mode -+- MIPI DBI (RFBI) output (not tested for a while, might've gotten broken) -+- SDI output -+- TV output -+- All pieces can be compiled as a module or inside kernel -+- Use DISPC to update any of the outputs -+- Use CPU to update RFBI or DSI output -+- OMAP DISPC planes -+- RGB16, RGB24 packed, RGB24 unpacked -+- YUV2, UYVY -+- Scaling -+- Adjusting DSS FCK to find a good pixel clock -+- Use DSI DPLL to create DSS FCK -+ -+omap-dss driver -+------------ -+ -+The DSS driver does not itself have any support for Linux framebuffer, V4L or -+such like the current ones, but it has an internal kernel API that upper level -+drivers can use. -+ -+The DSS driver models OMAP's overlays, overlay managers and displays in a -+flexible way to enable non-common multi-display configuration. In addition to -+modelling the hardware overlays, omap-dss supports virtual overlays and overlay -+managers. These can be used when updating a display with CPU or system DMA. -+ -+Panel and controller drivers -+---------------------------- -+ -+The drivers implement panel or controller specific functionality and are not -+visible to users except through omapfb driver. They register themselves to the -+DSS driver. -+ -+omapfb driver -+------------- -+ -+The omapfb driver implements arbitrary number of standard linux framebuffers. -+These framebuffers can be routed flexibly to any overlays, thus allowing very -+dynamic display architecture. -+ -+The driver exports some omapfb specific ioctls, which are compatible with the -+ioctls in the old driver. -+ -+The rest of the non standard features are exported via sysfs. Whether the final -+implementation will use sysfs, or ioctls, is still open. -+ -+V4L2 drivers -+------------ -+ -+Currently there are no V4L2 display drivers planned, but it is possible to -+implement such either to omapfb driver, or as a separate one. From omap-dss -+point of view the V4L2 drivers should be similar to framebuffer driver. -+ -+Architecture -+-------------------- -+ -+Some clarification what the different components do: -+ -+ - Framebuffer is a memory area inside OMAP's SDRAM that contains the pixel -+ data for the image. Framebuffer has width and height and color depth. -+ - Overlay defines where the pixels are read from and where they go on the -+ screen. The overlay may be smaller than framebuffer, thus displaying only -+ part of the framebuffer. The position of the overlay may be changed if -+ the overlay is smaller than the display. -+ - Overlay manager combines the overlays in to one image and feeds them to -+ display. -+ - Display is the actual physical display device. -+ -+A framebuffer can be connected to multiple overlays to show the same pixel data -+on all of the overlays. Note that in this case the overlay input sizes must be -+the same, but, in case of video overlays, the output size can be different. Any -+framebuffer can be connected to any overlay. -+ -+An overlay can be connected to one overlay manager. Also DISPC overlays can be -+connected only to DISPC overlay managers, and virtual overlays can be only -+connected to virtual overlays. -+ -+An overlay manager can be connected to one display. There are certain -+restrictions which kinds of displays an overlay manager can be connected: -+ -+ - DISPC TV overlay manager can be only connected to TV display. -+ - Virtual overlay managers can only be connected to DBI or DSI displays. -+ - DISPC LCD overlay manager can be connected to all displays, except TV -+ display. -+ -+Sysfs -+----- -+The sysfs interface is a hack, but works for testing. I don't think sysfs -+interface is the best for this in the final version, but I don't quite know -+what would be the best interfaces for these things. -+ -+In /sys/devices/platform/omapfb we have four files: framebuffers, -+overlays, managers and displays. You can read them so see the current -+setup, and change them by writing to it in the form of -+"<item-id> <opt1>:<val1> <opt2>:<val2>..." -+ -+"framebuffers" lists all framebuffers. Its format is: -+ <fb number> -+ t:<target overlay> -+ -+"overlays" lists all overlays. Its format is: -+ <overlay name> -+ t:<target manager> -+ x:<xpos> -+ y:<ypos> -+ iw:<input width, read only> -+ ih:<input height, read only> -+ w:<output width> -+ h:<output height> -+ e:<enabled> -+ -+"managers" lists all overlay managers. Its format is: -+ <manager name> -+ t:<target display> -+ -+"displays" lists all displays. Its format is: -+ <display name> -+ w:<width> -+ h:<height> -+ e:<enabled> -+ u:<update mode> -+ t:<tear sync on/off> -+ -+There is also a debug sysfs file at /sys/devices/platform/omap-dss/clk which -+shows how DSS has configured the clocks. -+ -+Examples -+-------- -+ -+In the example scripts "omapfb" is a symlink to /sys/devices/platform/omapfb/. -+ -+Default setup on OMAP3 SDP -+-------------------------- -+ -+Here's the default setup on OMAP3 SDP board. All planes go to LCD. DVI -+and TV-out are not in use. The columns from left to right are: -+framebuffers, overlays, overlay managers, displays. Framebuffers are -+handled by omapfb, and the rest by the DSS. -+ -+FB0 --- GFX -\ DVI -+FB1 --- VID1 --+- LCD ---- LCD -+FB2 --- VID2 -/ TV ----- TV -+ -+Switch from LCD to DVI -+---------------------- -+ -+dviline=`cat omapfb/displays |grep dvi` -+w=`echo $dviline | cut -d " " -f 2 | cut -d ":" -f 2` -+h=`echo $dviline | cut -d " " -f 3 | cut -d ":" -f 2` -+ -+echo "lcd e:0" > omapfb/displays -+echo "lcd t:none" > omapfb/managers -+fbset -fb /dev/fb0 -xres $w -yres $h -+# at this point you have to switch the dvi/lcd dip-switch from the omap board -+echo "lcd t:dvi" > omapfb/managers -+echo "dvi e:1" > omapfb/displays -+ -+After this the configuration looks like: -+ -+FB0 --- GFX -\ -- DVI -+FB1 --- VID1 --+- LCD -/ LCD -+FB2 --- VID2 -/ TV ----- TV -+ -+Clone GFX overlay to LCD and TV -+------------------------------- -+ -+tvline=`cat /sys/devices/platform/omapfb/displays |grep tv` -+w=`echo $tvline | cut -d " " -f 2 | cut -d ":" -f 2` -+h=`echo $tvline | cut -d " " -f 3 | cut -d ":" -f 2` -+ -+echo "1 t:none" > omapfb/framebuffers -+echo "0 t:gfx,vid1" > omapfb/framebuffers -+echo "gfx e:1" > omapfb/overlays -+echo "vid1 t:tv w:$w h:$h e:1" > omapfb/overlays -+echo "tv e:1" > omapfb/displays -+ -+After this the configuration looks like (only relevant parts shown): -+ -+FB0 +-- GFX ---- LCD ---- LCD -+ \- VID1 ---- TV ---- TV -+ -+Misc notes -+---------- -+ -+OMAP FB allocates the framebuffer memory when it starts using -+dma_alloc_writecombine(). This requires large continuous physical memory areas -+and you can pre-reserve that area with "Consistent DMA memory size" Kconfig -+option. -+ -+Using DSI DPLL to generate pixel clock it is possible produce the pixel clock -+of 86.5MHz (max possible), and with that you get 1280x1024@57 output from DVI. -+ -+TODO -+---- -+ -+OMAP2 not tested for some time -+- DSS2 did work on OMAP2, but I haven't been able to test it for some time. -+ -+DSS locking -+ -+Error checking -+- Lots of checks are missing or implemented just as BUG() -+ -+Rotate (external FB) -+Rotate (VRFB) -+Rotate (SMS) -+ -+System DMA update for DSI -+- Can be used for RGB16 and RGB24P modes. Probably not for RGB24U (how -+ to skip the empty byte?) -+ -+Power management -+- Context saving -+ -+Resolution change -+- The x/y res of the framebuffer are not display resolutions, but the size -+ of the overlay. -+- The display resolution affects all planes on the display. -+ -+OMAP1 support -+- Not sure if needed -+ --- -1.5.6.3 - |