xref: /kernel/linux/linux-6.6/drivers/video/fbdev/omap/lcd_dma.c

// 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);