diff options
Diffstat (limited to 'Documentation/fb')
| -rw-r--r-- | Documentation/fb/sh7760fb.txt | 131 | ||||
| -rw-r--r-- | Documentation/fb/tridentfb.txt | 46 |
2 files changed, 162 insertions, 15 deletions
diff --git a/Documentation/fb/sh7760fb.txt b/Documentation/fb/sh7760fb.txt new file mode 100644 index 00000000000..c87bfe5c630 --- /dev/null +++ b/Documentation/fb/sh7760fb.txt @@ -0,0 +1,131 @@ +SH7760/SH7763 integrated LCDC Framebuffer driver +================================================ + +0. Overwiew +----------- +The SH7760/SH7763 have an integrated LCD Display controller (LCDC) which +supports (in theory) resolutions ranging from 1x1 to 1024x1024, +with color depths ranging from 1 to 16 bits, on STN, DSTN and TFT Panels. + +Caveats: +* Framebuffer memory must be a large chunk allocated at the top + of Area3 (HW requirement). Because of this requirement you should NOT + make the driver a module since at runtime it may become impossible to + get a large enough contiguous chunk of memory. + +* The driver does not support changing resolution while loaded + (displays aren't hotpluggable anyway) + +* Heavy flickering may be observed + a) if you're using 15/16bit color modes at >= 640x480 px resolutions, + b) during PCMCIA (or any other slow bus) activity. + +* Rotation works only 90degress clockwise, and only if horizontal + resolution is <= 320 pixels. + +files: drivers/video/sh7760fb.c + include/asm-sh/sh7760fb.h + Documentation/fb/sh7760fb.txt + +1. Platform setup +----------------- +SH7760: + Video data is fetched via the DMABRG DMA engine, so you have to + configure the SH DMAC for DMABRG mode (write 0x94808080 to the + DMARSRA register somewhere at boot). + + PFC registers PCCR and PCDR must be set to peripheral mode. + (write zeros to both). + +The driver does NOT do the above for you since board setup is, well, job +of the board setup code. + +2. Panel definitions +-------------------- +The LCDC must explicitly be told about the type of LCD panel +attached. Data must be wrapped in a "struct sh7760fb_platdata" and +passed to the driver as platform_data. + +Suggest you take a closer look at the SH7760 Manual, Section 30. +(http://documentation.renesas.com/eng/products/mpumcu/e602291_sh7760.pdf) + +The following code illustrates what needs to be done to +get the framebuffer working on a 640x480 TFT: + +====================== cut here ====================================== + +#include <linux/fb.h> +#include <asm/sh7760fb.h> + +/* + * NEC NL6440bc26-01 640x480 TFT + * dotclock 25175 kHz + * Xres 640 Yres 480 + * Htotal 800 Vtotal 525 + * HsynStart 656 VsynStart 490 + * HsynLenn 30 VsynLenn 2 + * + * The linux framebuffer layer does not use the syncstart/synclen + * values but right/left/upper/lower margin values. The comments + * for the x_margin explain how to calculate those from given + * panel sync timings. + */ +static struct fb_videomode nl6448bc26 = { + .name = "NL6448BC26", + .refresh = 60, + .xres = 640, + .yres = 480, + .pixclock = 39683, /* in picoseconds! */ + .hsync_len = 30, + .vsync_len = 2, + .left_margin = 114, /* HTOT - (HSYNSLEN + HSYNSTART) */ + .right_margin = 16, /* HSYNSTART - XRES */ + .upper_margin = 33, /* VTOT - (VSYNLEN + VSYNSTART) */ + .lower_margin = 10, /* VSYNSTART - YRES */ + .sync = FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT, + .vmode = FB_VMODE_NONINTERLACED, + .flag = 0, +}; + +static struct sh7760fb_platdata sh7760fb_nl6448 = { + .def_mode = &nl6448bc26, + .ldmtr = LDMTR_TFT_COLOR_16, /* 16bit TFT panel */ + .lddfr = LDDFR_8BPP, /* we want 8bit output */ + .ldpmmr = 0x0070, + .ldpspr = 0x0500, + .ldaclnr = 0, + .ldickr = LDICKR_CLKSRC(LCDC_CLKSRC_EXTERNAL) | + LDICKR_CLKDIV(1), + .rotate = 0, + .novsync = 1, + .blank = NULL, +}; + +/* SH7760: + * 0xFE300800: 256 * 4byte xRGB palette ram + * 0xFE300C00: 42 bytes ctrl registers + */ +static struct resource sh7760_lcdc_res[] = { + [0] = { + .start = 0xFE300800, + .end = 0xFE300CFF, + .flags = IORESOURCE_MEM, + }, + [1] = { + .start = 65, + .end = 65, + .flags = IORESOURCE_IRQ, + }, +}; + +static struct platform_device sh7760_lcdc_dev = { + .dev = { + .platform_data = &sh7760fb_nl6448, + }, + .name = "sh7760-lcdc", + .id = -1, + .resource = sh7760_lcdc_res, + .num_resources = ARRAY_SIZE(sh7760_lcdc_res), +}; + +====================== cut here ====================================== diff --git a/Documentation/fb/tridentfb.txt b/Documentation/fb/tridentfb.txt index 8a6c8a43e6a..45d9de5b13a 100644 --- a/Documentation/fb/tridentfb.txt +++ b/Documentation/fb/tridentfb.txt @@ -3,11 +3,25 @@ Tridentfb is a framebuffer driver for some Trident chip based cards. The following list of chips is thought to be supported although not all are tested: -those from the Image series with Cyber in their names - accelerated -those with Blade in their names (Blade3D,CyberBlade...) - accelerated -the newer CyberBladeXP family - nonaccelerated - -Only PCI/AGP based cards are supported, none of the older Tridents. +those from the TGUI series 9440/96XX and with Cyber in their names +those from the Image series and with Cyber in their names +those with Blade in their names (Blade3D,CyberBlade...) +the newer CyberBladeXP family + +All families are accelerated. Only PCI/AGP based cards are supported, +none of the older Tridents. +The driver supports 8, 16 and 32 bits per pixel depths. +The TGUI family requires a line length to be power of 2 if acceleration +is enabled. This means that range of possible resolutions and bpp is +limited comparing to the range if acceleration is disabled (see list +of parameters below). + +Known bugs: +1. The driver randomly locks up on 3DImage975 chip with acceleration + enabled. The same happens in X11 (Xorg). +2. The ramdac speeds require some more fine tuning. It is possible to + switch resolution which the chip does not support at some depths for + older chips. How to use it? ============== @@ -17,12 +31,11 @@ video=tridentfb The parameters for tridentfb are concatenated with a ':' as in this example. -video=tridentfb:800x600,bpp=16,noaccel +video=tridentfb:800x600-16@75,noaccel The second level parameters that tridentfb understands are: noaccel - turns off acceleration (when it doesn't work for your card) -accel - force text acceleration (for boards which by default are noacceled) fp - use flat panel related stuff crt - assume monitor is present instead of fp @@ -31,21 +44,24 @@ center - for flat panels and resolutions smaller than native size center the image, otherwise use stretch -memsize - integer value in Kb, use if your card's memory size is misdetected. +memsize - integer value in KB, use if your card's memory size is misdetected. look at the driver output to see what it says when initializing. -memdiff - integer value in Kb,should be nonzero if your card reports - more memory than it actually has.For instance mine is 192K less than + +memdiff - integer value in KB, should be nonzero if your card reports + more memory than it actually has. For instance mine is 192K less than detection says in all three BIOS selectable situations 2M, 4M, 8M. Only use if your video memory is taken from main memory hence of - configurable size.Otherwise use memsize. - If in some modes which barely fit the memory you see garbage at the bottom - this might help by not letting change to that mode anymore. + configurable size. Otherwise use memsize. + If in some modes which barely fit the memory you see garbage + at the bottom this might help by not letting change to that mode + anymore. nativex - the width in pixels of the flat panel.If you know it (usually 1024 800 or 1280) and it is not what the driver seems to detect use it. -bpp - bits per pixel (8,16 or 32) -mode - a mode name like 800x600 (as described in Documentation/fb/modedb.txt) +bpp - bits per pixel (8,16 or 32) +mode - a mode name like 800x600-8@75 as described in + Documentation/fb/modedb.txt Using insane values for the above parameters will probably result in driver misbehaviour so take care(for instance memsize=12345678 or memdiff=23784 or |