video: sh7760fb: SH7760/SH7763 LCDC framebuffer driver

Framebuffer driver for the SH7760/SH7763 integrated LCD controller.
Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
Reviewed-by: Paul Mundt <lethal@linux-sh.org>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Siegfried Schaefer <s.schaefer@schaefer-edv.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Documentation/fb/sh7760fb.txt

+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 ======================================

drivers/video/Kconfig

@@ -1991,6 +1991,19 @@ config FB_COBALT
 	tristate "Cobalt server LCD frame buffer support"
 	depends on FB && MIPS_COBALT
 
+config FB_SH7760
+       bool "SH7760/SH7763 LCDC support"
+       depends on FB && (CPU_SUBTYPE_SH7760 || CPU_SUBTYPE_SH7763)
+       select FB_CFB_FILLRECT
+       select FB_CFB_COPYAREA
+       select FB_CFB_IMAGEBLIT
+       help
+         Support for the SH7760/SH7763 integrated (D)STN/TFT LCD Controller.
+         Supports display resolutions up to 1024x1024 pixel, grayscale and
+         color operation, with depths ranging from 1 bpp to 8 bpp monochrome
+         and 8, 15 or 16 bpp color; 90 degrees clockwise display rotation for
+         panels <= 320 pixel horizontal resolution.
+
 config FB_VIRTUAL
 	tristate "Virtual Frame Buffer support (ONLY FOR TESTING!)"
 	depends on FB

drivers/video/Makefile

@@ -106,6 +106,7 @@ obj-$(CONFIG_FB_PMAGB_B)	  += pmagb-b-fb.o
 obj-$(CONFIG_FB_MAXINE)		  += maxinefb.o
 obj-$(CONFIG_FB_METRONOME)        += metronomefb.o
 obj-$(CONFIG_FB_S1D13XXX)	  += s1d13xxxfb.o
+obj-$(CONFIG_FB_SH7760)		  += sh7760fb.o
 obj-$(CONFIG_FB_IMX)              += imxfb.o
 obj-$(CONFIG_FB_S3C2410)	  += s3c2410fb.o
 obj-$(CONFIG_FB_FSL_DIU)	  += fsl-diu-fb.o

include/asm-sh/sh7760fb.h

+/*
+ * sh7760fb.h -- platform data for SH7760/SH7763 LCDC framebuffer driver.
+ *
+ * (c) 2006-2008 MSC Vertriebsges.m.b.H.,
+ * 			Manuel Lauss <mano@roarinelk.homelinux.net>
+ * (c) 2008 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
+ */
+
+#ifndef _ASM_SH_SH7760FB_H
+#define _ASM_SH_SH7760FB_H
+
+/*
+ * some bits of the colormap registers should be written as zero.
+ * create a mask for that.
+ */
+#define SH7760FB_PALETTE_MASK 0x00f8fcf8
+
+/* The LCDC dma engine always sets bits 27-26 to 1: this is Area3 */
+#define SH7760FB_DMA_MASK 0x0C000000
+
+/* palette */
+#define LDPR(x) (((x) << 2))
+
+/* framebuffer registers and bits */
+#define LDICKR 0x400
+#define LDMTR 0x402
+/* see sh7760fb.h for LDMTR bits */
+#define LDDFR 0x404
+#define LDDFR_PABD (1 << 8)
+#define LDDFR_COLOR_MASK 0x7F
+#define LDSMR 0x406
+#define LDSMR_ROT (1 << 13)
+#define LDSARU 0x408
+#define LDSARL 0x40c
+#define LDLAOR 0x410
+#define LDPALCR 0x412
+#define LDPALCR_PALS (1 << 4)
+#define LDPALCR_PALEN (1 << 0)
+#define LDHCNR 0x414
+#define LDHSYNR 0x416
+#define LDVDLNR 0x418
+#define LDVTLNR 0x41a
+#define LDVSYNR 0x41c
+#define LDACLNR 0x41e
+#define LDINTR 0x420
+#define LDPMMR 0x424
+#define LDPSPR 0x426
+#define LDCNTR 0x428
+#define LDCNTR_DON (1 << 0)
+#define LDCNTR_DON2 (1 << 4)
+
+#ifdef CONFIG_CPU_SUBTYPE_SH7763
+# define LDLIRNR       0x440
+/* LDINTR bit */
+# define LDINTR_MINTEN (1 << 15)
+# define LDINTR_FINTEN (1 << 14)
+# define LDINTR_VSINTEN (1 << 13)
+# define LDINTR_VEINTEN (1 << 12)
+# define LDINTR_MINTS (1 << 11)
+# define LDINTR_FINTS (1 << 10)
+# define LDINTR_VSINTS (1 << 9)
+# define LDINTR_VEINTS (1 << 8)
+# define VINT_START (LDINTR_VSINTEN)
+# define VINT_CHECK (LDINTR_VSINTS)
+#else
+/* LDINTR bit */
+# define LDINTR_VINTSEL (1 << 12)
+# define LDINTR_VINTE (1 << 8)
+# define LDINTR_VINTS (1 << 0)
+# define VINT_START (LDINTR_VINTSEL)
+# define VINT_CHECK (LDINTR_VINTS)
+#endif
+
+/* HSYNC polarity inversion */
+#define LDMTR_FLMPOL (1 << 15)
+
+/* VSYNC polarity inversion */
+#define LDMTR_CL1POL (1 << 14)
+
+/* DISPLAY-ENABLE polarity inversion */
+#define LDMTR_DISPEN_LOWACT (1 << 13)
+
+/* DISPLAY DATA BUS polarity inversion */
+#define LDMTR_DPOL_LOWACT (1 << 12)
+
+/* AC modulation signal enable */
+#define LDMTR_MCNT (1 << 10)
+
+/* Disable output of HSYNC during VSYNC period */
+#define LDMTR_CL1CNT (1 << 9)
+
+/* Disable output of VSYNC during VSYNC period */
+#define LDMTR_CL2CNT (1 << 8)
+
+/* Display types supported by the LCDC */
+#define LDMTR_STN_MONO_4       0x00
+#define LDMTR_STN_MONO_8       0x01
+#define LDMTR_STN_COLOR_4      0x08
+#define LDMTR_STN_COLOR_8      0x09
+#define LDMTR_STN_COLOR_12     0x0A
+#define LDMTR_STN_COLOR_16     0x0B
+#define LDMTR_DSTN_MONO_8      0x11
+#define LDMTR_DSTN_MONO_16     0x13
+#define LDMTR_DSTN_COLOR_8     0x19
+#define LDMTR_DSTN_COLOR_12    0x1A
+#define LDMTR_DSTN_COLOR_16    0x1B
+#define LDMTR_TFT_COLOR_16     0x2B
+
+/* framebuffer color layout */
+#define LDDFR_1BPP_MONO 0x00
+#define LDDFR_2BPP_MONO 0x01
+#define LDDFR_4BPP_MONO 0x02
+#define LDDFR_6BPP_MONO 0x04
+#define LDDFR_4BPP 0x0A
+#define LDDFR_8BPP 0x0C
+#define LDDFR_16BPP_RGB555 0x1D
+#define LDDFR_16BPP_RGB565 0x2D
+
+/* LCDC Pixclock sources */
+#define LCDC_CLKSRC_BUSCLOCK 0
+#define LCDC_CLKSRC_PERIPHERAL 1
+#define LCDC_CLKSRC_EXTERNAL 2
+
+#define LDICKR_CLKSRC(x) \
+       (((x) & 3) << 12)
+
+/* LCDC pixclock input divider. Set to 1 at a minimum! */
+#define LDICKR_CLKDIV(x) \
+       ((x) & 0x1f)
+
+struct sh7760fb_platdata {
+
+	/* Set this member to a valid fb_videmode for the display you
+	 * wish to use.  The following members must be initialized:
+	 * xres, yres, hsync_len, vsync_len, sync,
+	 * {left,right,upper,lower}_margin.
+	 * The driver uses the above members to calculate register values
+	 * and memory requirements. Other members are ignored but may
+	 * be used by other framebuffer layer components.
+	 */
+	struct fb_videomode *def_mode;
+
+	/* LDMTR includes display type and signal polarity.  The
+	 * HSYNC/VSYNC polarities are derived from the fb_var_screeninfo
+	 * data above; however the polarities of the following signals
+	 * must be encoded in the ldmtr member:
+	 * Display Enable signal (default high-active)  DISPEN_LOWACT
+	 * Display Data signals (default high-active)   DPOL_LOWACT
+	 * AC Modulation signal (default off)           MCNT
+	 * Hsync-During-Vsync suppression (default off) CL1CNT
+	 * Vsync-during-vsync suppression (default off) CL2CNT
+	 * NOTE: also set a display type!
+	 * (one of LDMTR_{STN,DSTN,TFT}_{MONO,COLOR}_{4,8,12,16})
+	 */
+	u16 ldmtr;
+
+	/* LDDFR controls framebuffer image format (depth, organization)
+	 * Use ONE of the LDDFR_?BPP_* macros!
+	 */
+	u16 lddfr;
+
+	/* LDPMMR and LDPSPR control the timing of the power signals
+	 * for the display. Please read the SH7760 Hardware Manual,
+	 * Chapters 30.3.17, 30.3.18 and 30.4.6!
+	 */
+	u16 ldpmmr;
+	u16 ldpspr;
+
+	/* LDACLNR contains the line numbers after which the AC modulation
+	 * signal is to toggle. Set to ZERO for TFTs or displays which
+	 * do not need it. (Chapter 30.3.15 in SH7760 Hardware Manual).
+	 */
+	u16 ldaclnr;
+
+	/* LDICKR contains information on pixelclock source and config.
+	 * Please use the LDICKR_CLKSRC() and LDICKR_CLKDIV() macros.
+	 * minimal value for CLKDIV() must be 1!.
+	 */
+	u16 ldickr;
+
+	/* set this member to 1 if you wish to use the LCDC's hardware
+	 * rotation function.  This is limited to displays <= 320x200
+	 * pixels resolution!
+	 */
+	int rotate;		/* set to 1 to rotate 90 CCW */
+
+	/* set this to 1 to suppress vsync irq use. */
+	int novsync;
+
+	/* blanking hook for platform. Set this if your platform can do
+	 * more than the LCDC in terms of blanking (e.g. disable clock
+	 * generator / backlight power supply / etc.
+	 */
+	void (*blank) (int);
+};
+
+#endif /* _ASM_SH_SH7760FB_H */