--- /dev/null
+SH7760/SH7763 integrated LCDC Framebuffer driver
+================================================
+
+0. Overview
+-----------
+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 ======================================
Code Review / kvmfornfv.git / blobdiff