// SPDX-License-Identifier: GPL-2.0-only
/*
 * OMAP2+ DMA driver
 *
 * 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.
 * 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>
 *
 * Copyright (C) 2010 Texas Instruments Incorporated - https://www.ti.com/
 * Converted DMA library into platform driver
 *      - G, Manjunath Kondaiah <manjugk@ti.com>
 */

#include <linux/err.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/of.h>
#include <linux/omap-dma.h>

#include "soc.h"
#include "common.h"

static const struct omap_dma_reg reg_map[] = {
        [REVISION]      = { 0x0000, 0x00, OMAP_DMA_REG_32BIT },
        [GCR]           = { 0x0078, 0x00, OMAP_DMA_REG_32BIT },
        [IRQSTATUS_L0]  = { 0x0008, 0x00, OMAP_DMA_REG_32BIT },
        [IRQSTATUS_L1]  = { 0x000c, 0x00, OMAP_DMA_REG_32BIT },
        [IRQSTATUS_L2]  = { 0x0010, 0x00, OMAP_DMA_REG_32BIT },
        [IRQSTATUS_L3]  = { 0x0014, 0x00, OMAP_DMA_REG_32BIT },
        [IRQENABLE_L0]  = { 0x0018, 0x00, OMAP_DMA_REG_32BIT },
        [IRQENABLE_L1]  = { 0x001c, 0x00, OMAP_DMA_REG_32BIT },
        [IRQENABLE_L2]  = { 0x0020, 0x00, OMAP_DMA_REG_32BIT },
        [IRQENABLE_L3]  = { 0x0024, 0x00, OMAP_DMA_REG_32BIT },
        [SYSSTATUS]     = { 0x0028, 0x00, OMAP_DMA_REG_32BIT },
        [OCP_SYSCONFIG] = { 0x002c, 0x00, OMAP_DMA_REG_32BIT },
        [CAPS_0]        = { 0x0064, 0x00, OMAP_DMA_REG_32BIT },
        [CAPS_2]        = { 0x006c, 0x00, OMAP_DMA_REG_32BIT },
        [CAPS_3]        = { 0x0070, 0x00, OMAP_DMA_REG_32BIT },
        [CAPS_4]        = { 0x0074, 0x00, OMAP_DMA_REG_32BIT },

        /* Common register offsets */
        [CCR]           = { 0x0080, 0x60, OMAP_DMA_REG_32BIT },
        [CLNK_CTRL]     = { 0x0084, 0x60, OMAP_DMA_REG_32BIT },
        [CICR]          = { 0x0088, 0x60, OMAP_DMA_REG_32BIT },
        [CSR]           = { 0x008c, 0x60, OMAP_DMA_REG_32BIT },
        [CSDP]          = { 0x0090, 0x60, OMAP_DMA_REG_32BIT },
        [CEN]           = { 0x0094, 0x60, OMAP_DMA_REG_32BIT },
        [CFN]           = { 0x0098, 0x60, OMAP_DMA_REG_32BIT },
        [CSEI]          = { 0x00a4, 0x60, OMAP_DMA_REG_32BIT },
        [CSFI]          = { 0x00a8, 0x60, OMAP_DMA_REG_32BIT },
        [CDEI]          = { 0x00ac, 0x60, OMAP_DMA_REG_32BIT },
        [CDFI]          = { 0x00b0, 0x60, OMAP_DMA_REG_32BIT },
        [CSAC]          = { 0x00b4, 0x60, OMAP_DMA_REG_32BIT },
        [CDAC]          = { 0x00b8, 0x60, OMAP_DMA_REG_32BIT },

        /* Channel specific register offsets */
        [CSSA]          = { 0x009c, 0x60, OMAP_DMA_REG_32BIT },
        [CDSA]          = { 0x00a0, 0x60, OMAP_DMA_REG_32BIT },
        [CCEN]          = { 0x00bc, 0x60, OMAP_DMA_REG_32BIT },
        [CCFN]          = { 0x00c0, 0x60, OMAP_DMA_REG_32BIT },
        [COLOR]         = { 0x00c4, 0x60, OMAP_DMA_REG_32BIT },

        /* OMAP4 specific registers */
        [CDP]           = { 0x00d0, 0x60, OMAP_DMA_REG_32BIT },
        [CNDP]          = { 0x00d4, 0x60, OMAP_DMA_REG_32BIT },
        [CCDN]          = { 0x00d8, 0x60, OMAP_DMA_REG_32BIT },
};

static unsigned configure_dma_errata(void)
{
        unsigned errata = 0;

        /*
         * Errata applicable for OMAP2430ES1.0 and all omap2420
         *
         * I.
         * Erratum ID: Not Available
         * Inter Frame DMA buffering issue DMA will wrongly
         * buffer elements if packing and bursting is enabled. This might
         * result in data gets stalled in FIFO at the end of the block.
         * Workaround: DMA channels must have BUFFERING_DISABLED bit set to
         * guarantee no data will stay in the DMA FIFO in case inter frame
         * buffering occurs
         *
         * II.
         * Erratum ID: Not Available
         * DMA may hang when several channels are used in parallel
         * In the following configuration, DMA channel hanging can occur:
         * a. Channel i, hardware synchronized, is enabled
         * b. Another channel (Channel x), software synchronized, is enabled.
         * c. Channel i is disabled before end of transfer
         * d. Channel i is reenabled.
         * e. Steps 1 to 4 are repeated a certain number of times.
         * f. A third channel (Channel y), software synchronized, is enabled.
         * Channel x and Channel y may hang immediately after step 'f'.
         * Workaround:
         * For any channel used - make sure NextLCH_ID is set to the value j.
         */
        if (cpu_is_omap2420() || (cpu_is_omap2430() &&
                                (omap_type() == OMAP2430_REV_ES1_0))) {

                SET_DMA_ERRATA(DMA_ERRATA_IFRAME_BUFFERING);
                SET_DMA_ERRATA(DMA_ERRATA_PARALLEL_CHANNELS);
        }

        /*
         * Erratum ID: i378: OMAP2+: sDMA Channel is not disabled
         * after a transaction error.
         * Workaround: SW should explicitely disable the channel.
         */
        if (cpu_class_is_omap2())
                SET_DMA_ERRATA(DMA_ERRATA_i378);

        /*
         * Erratum ID: i541: sDMA FIFO draining does not finish
         * If sDMA channel is disabled on the fly, sDMA enters standby even
         * through FIFO Drain is still in progress
         * Workaround: Put sDMA in NoStandby more before a logical channel is
         * disabled, then put it back to SmartStandby right after the channel
         * finishes FIFO draining.
         */
        if (cpu_is_omap34xx())
                SET_DMA_ERRATA(DMA_ERRATA_i541);

        /*
         * Erratum ID: i88 : Special programming model needed to disable DMA
         * before end of block.
         * Workaround: software must ensure that the DMA is configured in No
         * Standby mode(DMAx_OCP_SYSCONFIG.MIDLEMODE = "01")
         */
        if (omap_type() == OMAP3430_REV_ES1_0)
                SET_DMA_ERRATA(DMA_ERRATA_i88);

        /*
         * Erratum 3.2/3.3: sometimes 0 is returned if CSAC/CDAC is
         * read before the DMA controller finished disabling the channel.
         */
        SET_DMA_ERRATA(DMA_ERRATA_3_3);

        /*
         * Erratum ID: Not Available
         * A bug in ROM code leaves IRQ status for channels 0 and 1 uncleared
         * after secure sram context save and restore.
         * Work around: Hence we need to manually clear those IRQs to avoid
         * spurious interrupts. This affects only secure devices.
         */
        if (cpu_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
                SET_DMA_ERRATA(DMA_ROMCODE_BUG);

        return errata;
}

static const struct dma_slave_map omap24xx_sdma_dt_map[] = {
        /* external DMA requests when tusb6010 is used */
        { "musb-hdrc.1.auto", "dmareq0", SDMA_FILTER_PARAM(2) },
        { "musb-hdrc.1.auto", "dmareq1", SDMA_FILTER_PARAM(3) },
        { "musb-hdrc.1.auto", "dmareq2", SDMA_FILTER_PARAM(14) }, /* OMAP2420 only */
        { "musb-hdrc.1.auto", "dmareq3", SDMA_FILTER_PARAM(15) }, /* OMAP2420 only */
        { "musb-hdrc.1.auto", "dmareq4", SDMA_FILTER_PARAM(16) }, /* OMAP2420 only */
        { "musb-hdrc.1.auto", "dmareq5", SDMA_FILTER_PARAM(64) }, /* OMAP2420 only */
};

static struct omap_dma_dev_attr dma_attr = {
        .dev_caps = RESERVE_CHANNEL | DMA_LINKED_LCH | GLOBAL_PRIORITY |
                    IS_CSSA_32 | IS_CDSA_32,
        .lch_count = 32,
};

struct omap_system_dma_plat_info dma_plat_info = {
        .reg_map        = reg_map,
        .channel_stride = 0x60,
        .dma_attr       = &dma_attr,
};

/* One time initializations */
static int __init omap2_system_dma_init(void)
{
        dma_plat_info.errata = configure_dma_errata();

        if (soc_is_omap24xx()) {
                /* DMA slave map for drivers not yet converted to DT */
                dma_plat_info.slave_map = omap24xx_sdma_dt_map;
                dma_plat_info.slavecnt = ARRAY_SIZE(omap24xx_sdma_dt_map);
        }

        if (!soc_is_omap242x())
                dma_attr.dev_caps |= IS_RW_PRIORITY;

        if (soc_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
                dma_attr.dev_caps |= HS_CHANNELS_RESERVED;

        return 0;
}
omap_arch_initcall(omap2_system_dma_init);