drivers/video/fbdev/omap/lcd_dma.c - third_party/linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * linux/arch/arm/mach-omap1/lcd_dma.c
  *
  * Extracted from arch/arm/plat-omap/dma.c
  * Copyright (C) 2003 - 2008 Nokia Corporation
  * Author: Juha Yrjölä <juha.yrjola@nokia.com>
  * DMA channel linking for 1610 by Samuel Ortiz <samuel.ortiz@nokia.com>
  * Graphics DMA and LCD DMA graphics tranformations
  * by Imre Deak <imre.deak@nokia.com>
  * OMAP2/3 support Copyright (C) 2004-2007 Texas Instruments, Inc.
  * Merged to support both OMAP1 and OMAP2 by Tony Lindgren <tony@atomide.com>
  * Some functions based on earlier dma-omap.c Copyright (C) 2001 RidgeRun, Inc.
  *
  * Copyright (C) 2009 Texas Instruments
  * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
  *
  * Support functions for the OMAP internal DMA channels.
  */

 #include <linux/module.h>
 #include <linux/spinlock.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>

 #include <linux/omap-dma.h>

 #include <linux/soc/ti/omap1-soc.h>
 #include <linux/soc/ti/omap1-io.h>

 #include "lcdc.h"
 #include "lcd_dma.h"

 int omap_lcd_dma_running(void)
 {
 	/*
 	 * On OMAP1510, internal LCD controller will start the transfer
 	 * when it gets enabled, so assume DMA running if LCD enabled.
 	 */
 	if (cpu_is_omap15xx())
 		if (omap_readw(OMAP_LCDC_CONTROL) & OMAP_LCDC_CTRL_LCD_EN)
 			return 1;

 	/* Check if LCD DMA is running */
 	if (cpu_is_omap16xx())
 		if (omap_readw(OMAP1610_DMA_LCD_CCR) & OMAP_DMA_CCR_EN)
 			return 1;

 	return 0;
 }

 static struct lcd_dma_info {
 	spinlock_t lock;
 	int reserved;
 	void (*callback)(u16 status, void *data);
 	void *cb_data;

 	int active;
 	unsigned long addr;
 	int rotate, data_type, xres, yres;
 	int vxres;
 	int mirror;
 	int xscale, yscale;
 	int ext_ctrl;
 	int src_port;
 	int single_transfer;
 } lcd_dma;

 void omap_set_lcd_dma_b1(unsigned long addr, u16 fb_xres, u16 fb_yres,
 			 int data_type)
 {
 	lcd_dma.addr = addr;
 	lcd_dma.data_type = data_type;
 	lcd_dma.xres = fb_xres;
 	lcd_dma.yres = fb_yres;
 }
 EXPORT_SYMBOL(omap_set_lcd_dma_b1);

 void omap_set_lcd_dma_ext_controller(int external)
 {
 	lcd_dma.ext_ctrl = external;
 }
 EXPORT_SYMBOL(omap_set_lcd_dma_ext_controller);

 void omap_set_lcd_dma_single_transfer(int single)
 {
 	lcd_dma.single_transfer = single;
 }
 EXPORT_SYMBOL(omap_set_lcd_dma_single_transfer);

 void omap_set_lcd_dma_b1_rotation(int rotate)
 {
 	if (cpu_is_omap15xx()) {
 		printk(KERN_ERR "DMA rotation is not supported in 1510 mode\n");
 		BUG();
 		return;
 	}
 	lcd_dma.rotate = rotate;
 }
 EXPORT_SYMBOL(omap_set_lcd_dma_b1_rotation);

 void omap_set_lcd_dma_b1_mirror(int mirror)
 {
 	if (cpu_is_omap15xx()) {
 		printk(KERN_ERR "DMA mirror is not supported in 1510 mode\n");
 		BUG();
 	}
 	lcd_dma.mirror = mirror;
 }
 EXPORT_SYMBOL(omap_set_lcd_dma_b1_mirror);

 void omap_set_lcd_dma_b1_vxres(unsigned long vxres)
 {
 	if (cpu_is_omap15xx()) {
 		pr_err("DMA virtual resolution is not supported in 1510 mode\n");
 		BUG();
 	}
 	lcd_dma.vxres = vxres;
 }
 EXPORT_SYMBOL(omap_set_lcd_dma_b1_vxres);

 void omap_set_lcd_dma_b1_scale(unsigned int xscale, unsigned int yscale)
 {
 	if (cpu_is_omap15xx()) {
 		printk(KERN_ERR "DMA scale is not supported in 1510 mode\n");
 		BUG();
 	}
 	lcd_dma.xscale = xscale;
 	lcd_dma.yscale = yscale;
 }
 EXPORT_SYMBOL(omap_set_lcd_dma_b1_scale);

 static void set_b1_regs(void)
 {
 	unsigned long top, bottom;
 	int es;
 	u16 w;
 	unsigned long en, fn;
 	long ei, fi;
 	unsigned long vxres;
 	unsigned int xscale, yscale;

 	switch (lcd_dma.data_type) {
 	case OMAP_DMA_DATA_TYPE_S8:
 		es = 1;
 		break;
 	case OMAP_DMA_DATA_TYPE_S16:
 		es = 2;
 		break;
 	case OMAP_DMA_DATA_TYPE_S32:
 		es = 4;
 		break;
 	default:
 		BUG();
 		return;
 	}

 	vxres = lcd_dma.vxres ? lcd_dma.vxres : lcd_dma.xres;
 	xscale = lcd_dma.xscale ? lcd_dma.xscale : 1;
 	yscale = lcd_dma.yscale ? lcd_dma.yscale : 1;
 	BUG_ON(vxres < lcd_dma.xres);

 #define PIXADDR(x, y) (lcd_dma.addr +					\
 		((y) * vxres * yscale + (x) * xscale) * es)
 #define PIXSTEP(sx, sy, dx, dy) (PIXADDR(dx, dy) - PIXADDR(sx, sy) - es + 1)

 	switch (lcd_dma.rotate) {
 	case 0:
 		if (!lcd_dma.mirror) {
 			top = PIXADDR(0, 0);
 			bottom = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
 			/* 1510 DMA requires the bottom address to be 2 more
 			 * than the actual last memory access location. */
 			if (cpu_is_omap15xx() &&
 				lcd_dma.data_type == OMAP_DMA_DATA_TYPE_S32)
 					bottom += 2;
 			ei = PIXSTEP(0, 0, 1, 0);
 			fi = PIXSTEP(lcd_dma.xres - 1, 0, 0, 1);
 		} else {
 			top = PIXADDR(lcd_dma.xres - 1, 0);
 			bottom = PIXADDR(0, lcd_dma.yres - 1);
 			ei = PIXSTEP(1, 0, 0, 0);
 			fi = PIXSTEP(0, 0, lcd_dma.xres - 1, 1);
 		}
 		en = lcd_dma.xres;
 		fn = lcd_dma.yres;
 		break;
 	case 90:
 		if (!lcd_dma.mirror) {
 			top = PIXADDR(0, lcd_dma.yres - 1);
 			bottom = PIXADDR(lcd_dma.xres - 1, 0);
 			ei = PIXSTEP(0, 1, 0, 0);
 			fi = PIXSTEP(0, 0, 1, lcd_dma.yres - 1);
 		} else {
 			top = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
 			bottom = PIXADDR(0, 0);
 			ei = PIXSTEP(0, 1, 0, 0);
 			fi = PIXSTEP(1, 0, 0, lcd_dma.yres - 1);
 		}
 		en = lcd_dma.yres;
 		fn = lcd_dma.xres;
 		break;
 	case 180:
 		if (!lcd_dma.mirror) {
 			top = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
 			bottom = PIXADDR(0, 0);
 			ei = PIXSTEP(1, 0, 0, 0);
 			fi = PIXSTEP(0, 1, lcd_dma.xres - 1, 0);
 		} else {
 			top = PIXADDR(0, lcd_dma.yres - 1);
 			bottom = PIXADDR(lcd_dma.xres - 1, 0);
 			ei = PIXSTEP(0, 0, 1, 0);
 			fi = PIXSTEP(lcd_dma.xres - 1, 1, 0, 0);
 		}
 		en = lcd_dma.xres;
 		fn = lcd_dma.yres;
 		break;
 	case 270:
 		if (!lcd_dma.mirror) {
 			top = PIXADDR(lcd_dma.xres - 1, 0);
 			bottom = PIXADDR(0, lcd_dma.yres - 1);
 			ei = PIXSTEP(0, 0, 0, 1);
 			fi = PIXSTEP(1, lcd_dma.yres - 1, 0, 0);
 		} else {
 			top = PIXADDR(0, 0);
 			bottom = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
 			ei = PIXSTEP(0, 0, 0, 1);
 			fi = PIXSTEP(0, lcd_dma.yres - 1, 1, 0);
 		}
 		en = lcd_dma.yres;
 		fn = lcd_dma.xres;
 		break;
 	default:
 		BUG();
 		return;	/* Suppress warning about uninitialized vars */
 	}

 	if (cpu_is_omap15xx()) {
 		omap_writew(top >> 16, OMAP1510_DMA_LCD_TOP_F1_U);
 		omap_writew(top, OMAP1510_DMA_LCD_TOP_F1_L);
 		omap_writew(bottom >> 16, OMAP1510_DMA_LCD_BOT_F1_U);
 		omap_writew(bottom, OMAP1510_DMA_LCD_BOT_F1_L);

 		return;
 	}

 	/* 1610 regs */
 	omap_writew(top >> 16, OMAP1610_DMA_LCD_TOP_B1_U);
 	omap_writew(top, OMAP1610_DMA_LCD_TOP_B1_L);
 	omap_writew(bottom >> 16, OMAP1610_DMA_LCD_BOT_B1_U);
 	omap_writew(bottom, OMAP1610_DMA_LCD_BOT_B1_L);

 	omap_writew(en, OMAP1610_DMA_LCD_SRC_EN_B1);
 	omap_writew(fn, OMAP1610_DMA_LCD_SRC_FN_B1);

 	w = omap_readw(OMAP1610_DMA_LCD_CSDP);
 	w &= ~0x03;
 	w |= lcd_dma.data_type;
 	omap_writew(w, OMAP1610_DMA_LCD_CSDP);

 	w = omap_readw(OMAP1610_DMA_LCD_CTRL);
 	/* Always set the source port as SDRAM for now*/
 	w &= ~(0x03 << 6);
 	if (lcd_dma.callback != NULL)
 		w |= 1 << 1;		/* Block interrupt enable */
 	else
 		w &= ~(1 << 1);
 	omap_writew(w, OMAP1610_DMA_LCD_CTRL);

 	if (!(lcd_dma.rotate || lcd_dma.mirror ||
 	      lcd_dma.vxres || lcd_dma.xscale || lcd_dma.yscale))
 		return;

 	w = omap_readw(OMAP1610_DMA_LCD_CCR);
 	/* Set the double-indexed addressing mode */
 	w |= (0x03 << 12);
 	omap_writew(w, OMAP1610_DMA_LCD_CCR);

 	omap_writew(ei, OMAP1610_DMA_LCD_SRC_EI_B1);
 	omap_writew(fi >> 16, OMAP1610_DMA_LCD_SRC_FI_B1_U);
 	omap_writew(fi, OMAP1610_DMA_LCD_SRC_FI_B1_L);
 }

 static irqreturn_t lcd_dma_irq_handler(int irq, void *dev_id)
 {
 	u16 w;

 	w = omap_readw(OMAP1610_DMA_LCD_CTRL);
 	if (unlikely(!(w & (1 << 3)))) {
 		printk(KERN_WARNING "Spurious LCD DMA IRQ\n");
 		return IRQ_NONE;
 	}
 	/* Ack the IRQ */
 	w |= (1 << 3);
 	omap_writew(w, OMAP1610_DMA_LCD_CTRL);
 	lcd_dma.active = 0;
 	if (lcd_dma.callback != NULL)
 		lcd_dma.callback(w, lcd_dma.cb_data);

 	return IRQ_HANDLED;
 }

 int omap_request_lcd_dma(void (*callback)(u16 status, void *data),
 			 void *data)
 {
 	spin_lock_irq(&lcd_dma.lock);
 	if (lcd_dma.reserved) {
 		spin_unlock_irq(&lcd_dma.lock);
 		printk(KERN_ERR "LCD DMA channel already reserved\n");
 		BUG();
 		return -EBUSY;
 	}
 	lcd_dma.reserved = 1;
 	spin_unlock_irq(&lcd_dma.lock);
 	lcd_dma.callback = callback;
 	lcd_dma.cb_data = data;
 	lcd_dma.active = 0;
 	lcd_dma.single_transfer = 0;
 	lcd_dma.rotate = 0;
 	lcd_dma.vxres = 0;
 	lcd_dma.mirror = 0;
 	lcd_dma.xscale = 0;
 	lcd_dma.yscale = 0;
 	lcd_dma.ext_ctrl = 0;
 	lcd_dma.src_port = 0;

 	return 0;
 }
 EXPORT_SYMBOL(omap_request_lcd_dma);

 void omap_free_lcd_dma(void)
 {
 	spin_lock(&lcd_dma.lock);
 	if (!lcd_dma.reserved) {
 		spin_unlock(&lcd_dma.lock);
 		printk(KERN_ERR "LCD DMA is not reserved\n");
 		BUG();
 		return;
 	}
 	if (!cpu_is_omap15xx())
 		omap_writew(omap_readw(OMAP1610_DMA_LCD_CCR) & ~1,
 			    OMAP1610_DMA_LCD_CCR);
 	lcd_dma.reserved = 0;
 	spin_unlock(&lcd_dma.lock);
 }
 EXPORT_SYMBOL(omap_free_lcd_dma);

 void omap_enable_lcd_dma(void)
 {
 	u16 w;

 	/*
 	 * Set the Enable bit only if an external controller is
 	 * connected. Otherwise the OMAP internal controller will
 	 * start the transfer when it gets enabled.
 	 */
 	if (cpu_is_omap15xx() || !lcd_dma.ext_ctrl)
 		return;

 	w = omap_readw(OMAP1610_DMA_LCD_CTRL);
 	w |= 1 << 8;
 	omap_writew(w, OMAP1610_DMA_LCD_CTRL);

 	lcd_dma.active = 1;

 	w = omap_readw(OMAP1610_DMA_LCD_CCR);
 	w |= 1 << 7;
 	omap_writew(w, OMAP1610_DMA_LCD_CCR);
 }
 EXPORT_SYMBOL(omap_enable_lcd_dma);

 void omap_setup_lcd_dma(void)
 {
 	BUG_ON(lcd_dma.active);
 	if (!cpu_is_omap15xx()) {
 		/* Set some reasonable defaults */
 		omap_writew(0x5440, OMAP1610_DMA_LCD_CCR);
 		omap_writew(0x9102, OMAP1610_DMA_LCD_CSDP);
 		omap_writew(0x0004, OMAP1610_DMA_LCD_LCH_CTRL);
 	}
 	set_b1_regs();
 	if (!cpu_is_omap15xx()) {
 		u16 w;

 		w = omap_readw(OMAP1610_DMA_LCD_CCR);
 		/*
 		 * If DMA was already active set the end_prog bit to have
 		 * the programmed register set loaded into the active
 		 * register set.
 		 */
 		w |= 1 << 11;		/* End_prog */
 		if (!lcd_dma.single_transfer)
 			w |= (3 << 8);	/* Auto_init, repeat */
 		omap_writew(w, OMAP1610_DMA_LCD_CCR);
 	}
 }
 EXPORT_SYMBOL(omap_setup_lcd_dma);

 void omap_stop_lcd_dma(void)
 {
 	u16 w;

 	lcd_dma.active = 0;
 	if (cpu_is_omap15xx() || !lcd_dma.ext_ctrl)
 		return;

 	w = omap_readw(OMAP1610_DMA_LCD_CCR);
 	w &= ~(1 << 7);
 	omap_writew(w, OMAP1610_DMA_LCD_CCR);

 	w = omap_readw(OMAP1610_DMA_LCD_CTRL);
 	w &= ~(1 << 8);
 	omap_writew(w, OMAP1610_DMA_LCD_CTRL);
 }
 EXPORT_SYMBOL(omap_stop_lcd_dma);

 static int __init omap_init_lcd_dma(void)
 {
 	int r;

 	if (!cpu_class_is_omap1())
 		return -ENODEV;

 	if (cpu_is_omap16xx()) {
 		u16 w;

 		/* this would prevent OMAP sleep */
 		w = omap_readw(OMAP1610_DMA_LCD_CTRL);
 		w &= ~(1 << 8);
 		omap_writew(w, OMAP1610_DMA_LCD_CTRL);
 	}

 	spin_lock_init(&lcd_dma.lock);

 	r = request_irq(INT_DMA_LCD, lcd_dma_irq_handler, 0,
 			"LCD DMA", NULL);
 	if (r != 0)
 		pr_err("unable to request IRQ for LCD DMA (error %d)\n", r);

 	return r;
 }

 arch_initcall(omap_init_lcd_dma);
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* linux/arch/arm/mach-omap1/lcd_dma.c
	*
	* Extracted from arch/arm/plat-omap/dma.c
	* Copyright (C) 2003 - 2008 Nokia Corporation
	* Author: Juha Yrjölä <juha.yrjola@nokia.com>
	* DMA channel linking for 1610 by Samuel Ortiz <samuel.ortiz@nokia.com>
	* Graphics DMA and LCD DMA graphics tranformations
	* by Imre Deak <imre.deak@nokia.com>
	* OMAP2/3 support Copyright (C) 2004-2007 Texas Instruments, Inc.
	* Merged to support both OMAP1 and OMAP2 by Tony Lindgren <tony@atomide.com>
	* Some functions based on earlier dma-omap.c Copyright (C) 2001 RidgeRun, Inc.
	*
	* Copyright (C) 2009 Texas Instruments
	* Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
	*
	* Support functions for the OMAP internal DMA channels.
	*/

	#include <linux/module.h>
	#include <linux/spinlock.h>
	#include <linux/interrupt.h>
	#include <linux/io.h>

	#include <linux/omap-dma.h>

	#include <linux/soc/ti/omap1-soc.h>
	#include <linux/soc/ti/omap1-io.h>

	#include "lcdc.h"
	#include "lcd_dma.h"

	int omap_lcd_dma_running(void)
	{
	/*
	* On OMAP1510, internal LCD controller will start the transfer
	* when it gets enabled, so assume DMA running if LCD enabled.
	*/
	if (cpu_is_omap15xx())
	if (omap_readw(OMAP_LCDC_CONTROL) & OMAP_LCDC_CTRL_LCD_EN)
	return 1;

	/* Check if LCD DMA is running */
	if (cpu_is_omap16xx())
	if (omap_readw(OMAP1610_DMA_LCD_CCR) & OMAP_DMA_CCR_EN)
	return 1;

	return 0;
	}

	static struct lcd_dma_info {
	spinlock_t lock;
	int reserved;
	void (callback)(u16 status, void data);
	void *cb_data;

	int active;
	unsigned long addr;
	int rotate, data_type, xres, yres;
	int vxres;
	int mirror;
	int xscale, yscale;
	int ext_ctrl;
	int src_port;
	int single_transfer;
	} lcd_dma;

	void omap_set_lcd_dma_b1(unsigned long addr, u16 fb_xres, u16 fb_yres,
	int data_type)
	{
	lcd_dma.addr = addr;
	lcd_dma.data_type = data_type;
	lcd_dma.xres = fb_xres;
	lcd_dma.yres = fb_yres;
	}
	EXPORT_SYMBOL(omap_set_lcd_dma_b1);

	void omap_set_lcd_dma_ext_controller(int external)
	{
	lcd_dma.ext_ctrl = external;
	}
	EXPORT_SYMBOL(omap_set_lcd_dma_ext_controller);

	void omap_set_lcd_dma_single_transfer(int single)
	{
	lcd_dma.single_transfer = single;
	}
	EXPORT_SYMBOL(omap_set_lcd_dma_single_transfer);

	void omap_set_lcd_dma_b1_rotation(int rotate)
	{
	if (cpu_is_omap15xx()) {
	printk(KERN_ERR "DMA rotation is not supported in 1510 mode\n");
	BUG();
	return;
	}
	lcd_dma.rotate = rotate;
	}
	EXPORT_SYMBOL(omap_set_lcd_dma_b1_rotation);

	void omap_set_lcd_dma_b1_mirror(int mirror)
	{
	if (cpu_is_omap15xx()) {
	printk(KERN_ERR "DMA mirror is not supported in 1510 mode\n");
	BUG();
	}
	lcd_dma.mirror = mirror;
	}
	EXPORT_SYMBOL(omap_set_lcd_dma_b1_mirror);

	void omap_set_lcd_dma_b1_vxres(unsigned long vxres)
	{
	if (cpu_is_omap15xx()) {
	pr_err("DMA virtual resolution is not supported in 1510 mode\n");
	BUG();
	}
	lcd_dma.vxres = vxres;
	}
	EXPORT_SYMBOL(omap_set_lcd_dma_b1_vxres);

	void omap_set_lcd_dma_b1_scale(unsigned int xscale, unsigned int yscale)
	{
	if (cpu_is_omap15xx()) {
	printk(KERN_ERR "DMA scale is not supported in 1510 mode\n");
	BUG();
	}
	lcd_dma.xscale = xscale;
	lcd_dma.yscale = yscale;
	}
	EXPORT_SYMBOL(omap_set_lcd_dma_b1_scale);

	static void set_b1_regs(void)
	{
	unsigned long top, bottom;
	int es;
	u16 w;
	unsigned long en, fn;
	long ei, fi;
	unsigned long vxres;
	unsigned int xscale, yscale;

	switch (lcd_dma.data_type) {
	case OMAP_DMA_DATA_TYPE_S8:
	es = 1;
	break;
	case OMAP_DMA_DATA_TYPE_S16:
	es = 2;
	break;
	case OMAP_DMA_DATA_TYPE_S32:
	es = 4;
	break;
	default:
	BUG();
	return;
	}

	vxres = lcd_dma.vxres ? lcd_dma.vxres : lcd_dma.xres;
	xscale = lcd_dma.xscale ? lcd_dma.xscale : 1;
	yscale = lcd_dma.yscale ? lcd_dma.yscale : 1;
	BUG_ON(vxres < lcd_dma.xres);

	#define PIXADDR(x, y) (lcd_dma.addr + \
	((y) * vxres * yscale + (x) * xscale) * es)
	#define PIXSTEP(sx, sy, dx, dy) (PIXADDR(dx, dy) - PIXADDR(sx, sy) - es + 1)

	switch (lcd_dma.rotate) {
	case 0:
	if (!lcd_dma.mirror) {
	top = PIXADDR(0, 0);
	bottom = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
	/* 1510 DMA requires the bottom address to be 2 more
	* than the actual last memory access location. */
	if (cpu_is_omap15xx() &&
	lcd_dma.data_type == OMAP_DMA_DATA_TYPE_S32)
	bottom += 2;
	ei = PIXSTEP(0, 0, 1, 0);
	fi = PIXSTEP(lcd_dma.xres - 1, 0, 0, 1);
	} else {
	top = PIXADDR(lcd_dma.xres - 1, 0);
	bottom = PIXADDR(0, lcd_dma.yres - 1);
	ei = PIXSTEP(1, 0, 0, 0);
	fi = PIXSTEP(0, 0, lcd_dma.xres - 1, 1);
	}
	en = lcd_dma.xres;
	fn = lcd_dma.yres;
	break;
	case 90:
	if (!lcd_dma.mirror) {
	top = PIXADDR(0, lcd_dma.yres - 1);
	bottom = PIXADDR(lcd_dma.xres - 1, 0);
	ei = PIXSTEP(0, 1, 0, 0);
	fi = PIXSTEP(0, 0, 1, lcd_dma.yres - 1);
	} else {
	top = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
	bottom = PIXADDR(0, 0);
	ei = PIXSTEP(0, 1, 0, 0);
	fi = PIXSTEP(1, 0, 0, lcd_dma.yres - 1);
	}
	en = lcd_dma.yres;
	fn = lcd_dma.xres;
	break;
	case 180:
	if (!lcd_dma.mirror) {
	top = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
	bottom = PIXADDR(0, 0);
	ei = PIXSTEP(1, 0, 0, 0);
	fi = PIXSTEP(0, 1, lcd_dma.xres - 1, 0);
	} else {
	top = PIXADDR(0, lcd_dma.yres - 1);
	bottom = PIXADDR(lcd_dma.xres - 1, 0);
	ei = PIXSTEP(0, 0, 1, 0);
	fi = PIXSTEP(lcd_dma.xres - 1, 1, 0, 0);
	}
	en = lcd_dma.xres;
	fn = lcd_dma.yres;
	break;
	case 270:
	if (!lcd_dma.mirror) {
	top = PIXADDR(lcd_dma.xres - 1, 0);
	bottom = PIXADDR(0, lcd_dma.yres - 1);
	ei = PIXSTEP(0, 0, 0, 1);
	fi = PIXSTEP(1, lcd_dma.yres - 1, 0, 0);
	} else {
	top = PIXADDR(0, 0);
	bottom = PIXADDR(lcd_dma.xres - 1, lcd_dma.yres - 1);
	ei = PIXSTEP(0, 0, 0, 1);
	fi = PIXSTEP(0, lcd_dma.yres - 1, 1, 0);
	}
	en = lcd_dma.yres;
	fn = lcd_dma.xres;
	break;
	default:
	BUG();
	return; /* Suppress warning about uninitialized vars */
	}

	if (cpu_is_omap15xx()) {
	omap_writew(top >> 16, OMAP1510_DMA_LCD_TOP_F1_U);
	omap_writew(top, OMAP1510_DMA_LCD_TOP_F1_L);
	omap_writew(bottom >> 16, OMAP1510_DMA_LCD_BOT_F1_U);
	omap_writew(bottom, OMAP1510_DMA_LCD_BOT_F1_L);

	return;
	}

	/* 1610 regs */
	omap_writew(top >> 16, OMAP1610_DMA_LCD_TOP_B1_U);
	omap_writew(top, OMAP1610_DMA_LCD_TOP_B1_L);
	omap_writew(bottom >> 16, OMAP1610_DMA_LCD_BOT_B1_U);
	omap_writew(bottom, OMAP1610_DMA_LCD_BOT_B1_L);

	omap_writew(en, OMAP1610_DMA_LCD_SRC_EN_B1);
	omap_writew(fn, OMAP1610_DMA_LCD_SRC_FN_B1);

	w = omap_readw(OMAP1610_DMA_LCD_CSDP);
	w &= ~0x03;
	w \|= lcd_dma.data_type;
	omap_writew(w, OMAP1610_DMA_LCD_CSDP);

	w = omap_readw(OMAP1610_DMA_LCD_CTRL);
	/* Always set the source port as SDRAM for now*/
	w &= ~(0x03 << 6);
	if (lcd_dma.callback != NULL)
	w \|= 1 << 1; /* Block interrupt enable */
	else
	w &= ~(1 << 1);
	omap_writew(w, OMAP1610_DMA_LCD_CTRL);

	if (!(lcd_dma.rotate \|\| lcd_dma.mirror \|\|
	lcd_dma.vxres \|\| lcd_dma.xscale \|\| lcd_dma.yscale))
	return;

	w = omap_readw(OMAP1610_DMA_LCD_CCR);
	/* Set the double-indexed addressing mode */
	w \|= (0x03 << 12);
	omap_writew(w, OMAP1610_DMA_LCD_CCR);

	omap_writew(ei, OMAP1610_DMA_LCD_SRC_EI_B1);
	omap_writew(fi >> 16, OMAP1610_DMA_LCD_SRC_FI_B1_U);
	omap_writew(fi, OMAP1610_DMA_LCD_SRC_FI_B1_L);
	}

	static irqreturn_t lcd_dma_irq_handler(int irq, void *dev_id)
	{
	u16 w;

	w = omap_readw(OMAP1610_DMA_LCD_CTRL);
	if (unlikely(!(w & (1 << 3)))) {
	printk(KERN_WARNING "Spurious LCD DMA IRQ\n");
	return IRQ_NONE;
	}
	/* Ack the IRQ */
	w \|= (1 << 3);
	omap_writew(w, OMAP1610_DMA_LCD_CTRL);
	lcd_dma.active = 0;
	if (lcd_dma.callback != NULL)
	lcd_dma.callback(w, lcd_dma.cb_data);

	return IRQ_HANDLED;
	}

	int omap_request_lcd_dma(void (callback)(u16 status, void data),
	void *data)
	{
	spin_lock_irq(&lcd_dma.lock);
	if (lcd_dma.reserved) {
	spin_unlock_irq(&lcd_dma.lock);
	printk(KERN_ERR "LCD DMA channel already reserved\n");
	BUG();
	return -EBUSY;
	}
	lcd_dma.reserved = 1;
	spin_unlock_irq(&lcd_dma.lock);
	lcd_dma.callback = callback;
	lcd_dma.cb_data = data;
	lcd_dma.active = 0;
	lcd_dma.single_transfer = 0;
	lcd_dma.rotate = 0;
	lcd_dma.vxres = 0;
	lcd_dma.mirror = 0;
	lcd_dma.xscale = 0;
	lcd_dma.yscale = 0;
	lcd_dma.ext_ctrl = 0;
	lcd_dma.src_port = 0;

	return 0;
	}
	EXPORT_SYMBOL(omap_request_lcd_dma);

	void omap_free_lcd_dma(void)
	{
	spin_lock(&lcd_dma.lock);
	if (!lcd_dma.reserved) {
	spin_unlock(&lcd_dma.lock);
	printk(KERN_ERR "LCD DMA is not reserved\n");
	BUG();
	return;
	}
	if (!cpu_is_omap15xx())
	omap_writew(omap_readw(OMAP1610_DMA_LCD_CCR) & ~1,
	OMAP1610_DMA_LCD_CCR);
	lcd_dma.reserved = 0;
	spin_unlock(&lcd_dma.lock);
	}
	EXPORT_SYMBOL(omap_free_lcd_dma);

	void omap_enable_lcd_dma(void)
	{
	u16 w;

	/*
	* Set the Enable bit only if an external controller is
	* connected. Otherwise the OMAP internal controller will
	* start the transfer when it gets enabled.
	*/
	if (cpu_is_omap15xx() \|\| !lcd_dma.ext_ctrl)
	return;

	w = omap_readw(OMAP1610_DMA_LCD_CTRL);
	w \|= 1 << 8;
	omap_writew(w, OMAP1610_DMA_LCD_CTRL);

	lcd_dma.active = 1;

	w = omap_readw(OMAP1610_DMA_LCD_CCR);
	w \|= 1 << 7;
	omap_writew(w, OMAP1610_DMA_LCD_CCR);
	}
	EXPORT_SYMBOL(omap_enable_lcd_dma);

	void omap_setup_lcd_dma(void)
	{
	BUG_ON(lcd_dma.active);
	if (!cpu_is_omap15xx()) {
	/* Set some reasonable defaults */
	omap_writew(0x5440, OMAP1610_DMA_LCD_CCR);
	omap_writew(0x9102, OMAP1610_DMA_LCD_CSDP);
	omap_writew(0x0004, OMAP1610_DMA_LCD_LCH_CTRL);
	}
	set_b1_regs();
	if (!cpu_is_omap15xx()) {
	u16 w;

	w = omap_readw(OMAP1610_DMA_LCD_CCR);
	/*
	* If DMA was already active set the end_prog bit to have
	* the programmed register set loaded into the active
	* register set.
	*/
	w \|= 1 << 11; /* End_prog */
	if (!lcd_dma.single_transfer)
	w \|= (3 << 8); /* Auto_init, repeat */
	omap_writew(w, OMAP1610_DMA_LCD_CCR);
	}
	}
	EXPORT_SYMBOL(omap_setup_lcd_dma);

	void omap_stop_lcd_dma(void)
	{
	u16 w;

	lcd_dma.active = 0;
	if (cpu_is_omap15xx() \|\| !lcd_dma.ext_ctrl)
	return;

	w = omap_readw(OMAP1610_DMA_LCD_CCR);
	w &= ~(1 << 7);
	omap_writew(w, OMAP1610_DMA_LCD_CCR);

	w = omap_readw(OMAP1610_DMA_LCD_CTRL);
	w &= ~(1 << 8);
	omap_writew(w, OMAP1610_DMA_LCD_CTRL);
	}
	EXPORT_SYMBOL(omap_stop_lcd_dma);

	static int __init omap_init_lcd_dma(void)
	{
	int r;

	if (!cpu_class_is_omap1())
	return -ENODEV;

	if (cpu_is_omap16xx()) {
	u16 w;

	/* this would prevent OMAP sleep */
	w = omap_readw(OMAP1610_DMA_LCD_CTRL);
	w &= ~(1 << 8);
	omap_writew(w, OMAP1610_DMA_LCD_CTRL);
	}

	spin_lock_init(&lcd_dma.lock);

	r = request_irq(INT_DMA_LCD, lcd_dma_irq_handler, 0,
	"LCD DMA", NULL);
	if (r != 0)
	pr_err("unable to request IRQ for LCD DMA (error %d)\n", r);

	return r;
	}

	arch_initcall(omap_init_lcd_dma);