[U-Boot] [PATCH] video: Add support for TI's AM335x LCD-Controller

Hannes Petermaier oe5hpm at oevsv.at
Thu Mar 6 14:39:06 CET 2014


- Adds support for a minimal framebuffer driver of TI's AM335x SoC
  to be compatible with Wolfgang Denk's LCD-Framework (CONFIG_LCD,
  common/lcd.c)

Signed-off-by: Hannes Petermaier <oe5hpm at oevsv.at>
---
 drivers/video/Makefile    |    1 +
 drivers/video/am335x-fb.c |  169 +++++++++++++++++++++++++++++++++++++++++++++
 drivers/video/am335x-fb.h |   67 ++++++++++++++++++
 3 files changed, 237 insertions(+)
 create mode 100644 drivers/video/am335x-fb.c
 create mode 100644 drivers/video/am335x-fb.h

diff --git a/drivers/video/Makefile b/drivers/video/Makefile
index a7f5469..ac3d6c7 100644
--- a/drivers/video/Makefile
+++ b/drivers/video/Makefile
@@ -39,3 +39,4 @@ obj-$(CONFIG_VIDEO_SMI_LYNXEM) += smiLynxEM.o videomodes.o
 obj-$(CONFIG_VIDEO_TEGRA) += tegra.o
 obj-$(CONFIG_VIDEO_VCXK) += bus_vcxk.o
 obj-$(CONFIG_FORMIKE) += formike.o
+obj-$(CONFIG_AM335X_LCD) += am335x-fb.o
diff --git a/drivers/video/am335x-fb.c b/drivers/video/am335x-fb.c
new file mode 100644
index 0000000..ab98941
--- /dev/null
+++ b/drivers/video/am335x-fb.c
@@ -0,0 +1,169 @@
+/*
+ * Copyright (C) 2013 Hannes Petermaier <oe5hpm at oevsv.at>
+ * Bernecker & Rainer Industrieelektronik GmbH - http://www.br-automation.com
+ *
+ * minimal framebuffer driver for TI's AM335x SoC to be compatible with
+ * Wolfgang Denk's LCD-Framework (CONFIG_LCD, common/lcd.c)
+ *
+ * - supporting only 24bit RGB/TFT raster Mode (not using palette)
+ * - sets up LCD controller as in 'am335x_lcdpanel' struct given
+ * - starts output DMA from gd->fb_base buffer
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+#include <common.h>
+#include <asm/arch/hardware.h>
+#include <lcd.h>
+#include "am335x-fb.h"
+
+#if !defined(LCD_CNTL_BASE)
+#error "hw-base address of LCD-Controller (LCD_CNTL_BASE) not defined!"
+#endif
+
+
+/* LCD Control Register */
+#define LCD_CLK_DIVISOR(x)			((x) << 8)
+#define LCD_RASTER_MODE				0x01
+/* LCD Clock Enable Register */
+#define LCD_CORECLKEN				(0x01 << 0)
+#define LCD_LIDDCLKEN				(0x01 << 1)
+#define LCD_DMACLKEN				(0x01 << 2)
+/* LCD DMA Control Register */
+#define LCD_DMA_BURST_SIZE(x)			((x) << 4)
+#define LCD_DMA_BURST_1				0x0
+#define LCD_DMA_BURST_2				0x1
+#define LCD_DMA_BURST_4				0x2
+#define LCD_DMA_BURST_8				0x3
+#define LCD_DMA_BURST_16			0x4
+/* LCD Timing_0 Register */
+#define LCD_HBPLSB(x)				((((x)-1) & 0xFF) << 24)
+#define LCD_HFPLSB(x)				((((x)-1) & 0xFF) << 16)
+#define LCD_HSWLSB(x)				((((x)-1) & 0x3F) << 10)
+#define LCD_HORLSB(x)				(((((x) >> 4)-1) & 0x3F) << 4)
+#define LCD_HORMSB(x)				(((((x) >> 4)-1) & 0x40) >> 4)
+/* LCD Timing_1 Register */
+#define LCD_VBP(x)				((x) << 24)
+#define LCD_VFP(x)				((x) << 16)
+#define LCD_VSW(x)				(((x)-1) << 10)
+#define LCD_VERLSB(x)				(((x)-1) & 0x3FF)
+/* LCD Timing_2 Register */
+#define LCD_HSWMSB(x)				((((x)-1) & 0x3C0) << 21)
+#define LCD_VERMSB(x)				((((x)-1) & 0x400) << 16)
+#define LCD_HBPMSB(x)				((((x)-1) & 0x300) >> 4)
+#define LCD_HFPMSB(x)				((((x)-1) & 0x300) >> 8)
+#define LCD_INVMASK(x)				((x) & 0x3F00000)
+/* LCD Raster Ctrl Register */
+#define LCD_TFT_24BPP_MODE			(1 << 25)
+#define LCD_TFT_24BPP_UNPACK			(1 << 26)
+#define LCD_PALMODE_RAWDATA			(0x10 << 20)
+#define LCD_TFT_MODE				(0x01 << 7)
+#define LCD_RASTER_ENABLE			(0x01 << 0)
+
+
+/* Macro definitions */
+#define FBSIZE(x)	((x->hactive * x->vactive * x->bpp) >> 3)
+
+struct am335x_lcdhw {
+	unsigned int		pid;			/* 0x00 */
+	unsigned int		ctrl;			/* 0x04 */
+	unsigned int		gap0;			/* 0x08 */
+	unsigned int		lidd_ctrl;		/* 0x0C */
+	unsigned int		lidd_cs0_conf;		/* 0x10 */
+	unsigned int		lidd_cs0_addr;		/* 0x14 */
+	unsigned int		lidd_cs0_data;		/* 0x18 */
+	unsigned int		lidd_cs1_conf;		/* 0x1C */
+	unsigned int		lidd_cs1_addr;		/* 0x20 */
+	unsigned int		lidd_cs1_data;		/* 0x24 */
+	unsigned int		raster_ctrl;		/* 0x28 */
+	unsigned int		raster_timing0;		/* 0x2C */
+	unsigned int		raster_timing1;		/* 0x30 */
+	unsigned int		raster_timing2;		/* 0x34 */
+	unsigned int		raster_subpanel;	/* 0x38 */
+	unsigned int		raster_subpanel2;	/* 0x3C */
+	unsigned int		lcddma_ctrl;		/* 0x40 */
+	unsigned int		lcddma_fb0_base;	/* 0x44 */
+	unsigned int		lcddma_fb0_ceiling;	/* 0x48 */
+	unsigned int		lcddma_fb1_base;	/* 0x4C */
+	unsigned int		lcddma_fb1_ceiling;	/* 0x50 */
+	unsigned int		sysconfig;		/* 0x54 */
+	unsigned int		irqstatus_raw;		/* 0x58 */
+	unsigned int		irqstatus;		/* 0x5C */
+	unsigned int		irqenable_set;		/* 0x60 */
+	unsigned int		irqenable_clear;	/* 0x64 */
+	unsigned int		gap1;			/* 0x68 */
+	unsigned int		clkc_enable;		/* 0x6C */
+	unsigned int		clkc_reset;		/* 0x70 */
+};
+
+static struct am335x_lcdhw *lcdhw = (void *)LCD_CNTL_BASE;
+DECLARE_GLOBAL_DATA_PTR;
+
+int lcd_get_size(int *line_length)
+{
+	*line_length = (panel_info.vl_col * NBITS(panel_info.vl_bpix)) / 8;
+	return *line_length * panel_info.vl_row + 0x20;
+}
+
+int am335xfb_init(struct am335x_lcdpanel *panel)
+{
+	if (0 == gd->fb_base) {
+		printf("ERROR: no valid fb_base stored in GLOBAL_DATA_PTR!\n");
+		return -1;
+	}
+	if (0 == panel) {
+		printf("ERROR: missing ptr to am335x_lcdpanel!\n");
+		return -1;
+	}
+
+	debug("setting up LCD-Controller for %dx%dx%d (hfp=%d,hbp=%d,hsw=%d / ",
+	      panel->hactive, panel->vactive, panel->bpp,
+	      panel->hfp, panel->hbp, panel->hsw);
+	debug("vfp=%d,vbp=%d,vsw=%d / clk-div=%d)\n",
+	      panel->vfp, panel->vfp, panel->vsw, panel->pxl_clk_div);
+	debug("using frambuffer at 0x%08x with size %d.\n",
+	      (unsigned int)gd->fb_base, FBSIZE(panel));
+
+	/* palette default entry */
+	memset((void *)gd->fb_base, 0, 0x20);
+	*(unsigned int *)gd->fb_base = 0x4000;
+
+	lcdhw->clkc_enable = LCD_CORECLKEN | LCD_LIDDCLKEN | LCD_DMACLKEN;
+	lcdhw->raster_ctrl = 0;
+	lcdhw->ctrl = LCD_CLK_DIVISOR(panel->pxl_clk_div) | LCD_RASTER_MODE;
+	lcdhw->lcddma_fb0_base = gd->fb_base;
+	lcdhw->lcddma_fb0_ceiling = gd->fb_base + FBSIZE(panel) + 0x20;
+	lcdhw->lcddma_fb1_base = gd->fb_base;
+	lcdhw->lcddma_fb1_ceiling = gd->fb_base + FBSIZE(panel) + 0x20;
+	lcdhw->lcddma_ctrl = LCD_DMA_BURST_SIZE(LCD_DMA_BURST_16);
+
+	lcdhw->raster_timing0 = LCD_HORLSB(panel->hactive) |
+				LCD_HORMSB(panel->hactive) |
+				LCD_HFPLSB(panel->hfp) |
+				LCD_HBPLSB(panel->hbp) |
+				LCD_HSWLSB(panel->hsw);
+	lcdhw->raster_timing1 = LCD_VBP(panel->vbp) |
+				LCD_VFP(panel->vfp) |
+				LCD_VSW(panel->vsw) |
+				LCD_VERLSB(panel->vactive);
+	lcdhw->raster_timing2 = LCD_HSWMSB(panel->hsw) |
+				LCD_VERMSB(panel->vactive) |
+				LCD_INVMASK(panel->pol) |
+				LCD_HBPMSB(panel->hbp) |
+				LCD_HFPMSB(panel->hfp) |
+				0x0000FF00;	/* clk cycles for ac-bias */
+	lcdhw->raster_ctrl =	LCD_TFT_24BPP_MODE |
+				LCD_TFT_24BPP_UNPACK |
+				LCD_PALMODE_RAWDATA |
+				LCD_TFT_MODE |
+				LCD_RASTER_ENABLE;
+
+	gd->fb_base += 0x20;	/* point fb behind palette */
+
+	/* turn ON display through powercontrol function if accessible */
+	if (0 != panel->panel_power_ctrl) {
+		mdelay(panel->pon_delay);
+		panel->panel_power_ctrl(1);
+	}
+
+	return 0;
+}
diff --git a/drivers/video/am335x-fb.h b/drivers/video/am335x-fb.h
new file mode 100644
index 0000000..8a0b131
--- /dev/null
+++ b/drivers/video/am335x-fb.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2013 Hannes Petermaier <oe5hpm at oevsv.at> -
+ * Bernecker & Rainer Industrieelektronik GmbH - http://www.br-automation.com
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef AM335X_FB_H
+#define AM335X_FB_H
+
+#define HSVS_CONTROL	(0x01 << 25)	/*
+					 * 0 = lcd_lp and lcd_fp are driven on
+					 * opposite edges of pixel clock than
+					 * the lcd_pixel_o
+					 * 1 = lcd_lp and lcd_fp are driven
+					 * according to bit 24 Note that this
+					 * bit MUST be set to '0' for Passive
+					 * Matrix displays the edge timing is
+					 * fixed
+					 */
+#define HSVS_RISEFALL	(0x01 << 24)	/*
+					 * 0 = lcd_lp and lcd_fp are driven on
+					 * the rising edge of pixel clock (bit
+					 * 25 must be set to 1)
+					 * 1 = lcd_lp and lcd_fp are driven on
+					 * the falling edge of pixel clock (bit
+					 * 25 must be set to 1)
+					 */
+#define DE_INVERT	(0x01 << 23)	/*
+					 * 0 = DE is low-active
+					 * 1 = DE is high-active
+					 */
+#define PXCLK_INVERT	(0x01 << 22)	/*
+					 * 0 = pix-clk is high-active
+					 * 1 = pic-clk is low-active
+					 */
+#define HSYNC_INVERT	(0x01 << 21)	/*
+					 * 0 = HSYNC is active high
+					 * 1 = HSYNC is avtive low
+					 */
+#define VSYNC_INVERT	(0x01 << 20)	/*
+					 * 0 = VSYNC is active high
+					 * 1 = VSYNC is active low
+					 */
+
+struct am335x_lcdpanel {
+	unsigned int	hactive;	/* Horizontal active area */
+	unsigned int	vactive;	/* Vertical active area */
+	unsigned int	bpp;		/* bits per pixel */
+	unsigned int	hfp;		/* Horizontal front porch */
+	unsigned int	hbp;		/* Horizontal back porch */
+	unsigned int	hsw;		/* Horizontal Sync Pulse Width */
+	unsigned int	vfp;		/* Vertical front porch */
+	unsigned int	vbp;		/* Vertical back porch */
+	unsigned int	vsw;		/* Vertical Sync Pulse Width */
+	unsigned int	pxl_clk_div;	/* Pixel clock divider*/
+	unsigned int	pol;		/* polarity of sync, clock signals */
+	unsigned int	pon_delay;	/*
+					 * time in ms for turning on lcd after
+					 * initializing lcd-controller
+					 */
+	void (*panel_power_ctrl)(int);	/* fp for power on/off display */
+};
+
+int am335xfb_init(struct am335x_lcdpanel *panel);
+
+#endif  /* AM335X_FB_H */
-- 
1.7.9.5



More information about the U-Boot mailing list