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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/Documentation/fb/arkfb.txt
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
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+
+ arkfb - fbdev driver for ARK Logic chips
+ ========================================
+
+
+Supported Hardware
+==================
+
+ ARK 2000PV chip
+ ICS 5342 ramdac
+
+ - only BIOS initialized VGA devices supported
+ - probably not working on big endian
+
+
+Supported Features
+==================
+
+ * 4 bpp pseudocolor modes (with 18bit palette, two variants)
+ * 8 bpp pseudocolor mode (with 18bit palette)
+ * 16 bpp truecolor modes (RGB 555 and RGB 565)
+ * 24 bpp truecolor mode (RGB 888)
+ * 32 bpp truecolor mode (RGB 888)
+ * text mode (activated by bpp = 0)
+ * doublescan mode variant (not available in text mode)
+ * panning in both directions
+ * suspend/resume support
+
+Text mode is supported even in higher resolutions, but there is limitation to
+lower pixclocks (i got maximum about 70 MHz, it is dependent on specific
+hardware). This limitation is not enforced by driver. Text mode supports 8bit
+wide fonts only (hardware limitation) and 16bit tall fonts (driver
+limitation). Unfortunately character attributes (like color) in text mode are
+broken for unknown reason, so its usefulness is limited.
+
+There are two 4 bpp modes. First mode (selected if nonstd == 0) is mode with
+packed pixels, high nibble first. Second mode (selected if nonstd == 1) is mode
+with interleaved planes (1 byte interleave), MSB first. Both modes support
+8bit wide fonts only (driver limitation).
+
+Suspend/resume works on systems that initialize video card during resume and
+if device is active (for example used by fbcon).
+
+
+Missing Features
+================
+(alias TODO list)
+
+ * secondary (not initialized by BIOS) device support
+ * big endian support
+ * DPMS support
+ * MMIO support
+ * interlaced mode variant
+ * support for fontwidths != 8 in 4 bpp modes
+ * support for fontheight != 16 in text mode
+ * hardware cursor
+ * vsync synchronization
+ * feature connector support
+ * acceleration support (8514-like 2D)
+
+
+Known bugs
+==========
+
+ * character attributes (and cursor) in text mode are broken
+
+--
+Ondrej Zajicek <santiago@crfreenet.org>