// 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/export.h>
#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_threaded_irq(INT_DMA_LCD, NULL, lcd_dma_irq_handler,
                                 IRQF_ONESHOT, "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);