linux/arch/arm/mach-omap2/dma.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * OMAP2+ DMA driver
   4 *
   5 * Copyright (C) 2003 - 2008 Nokia Corporation
   6 * Author: Juha Yrjölä <juha.yrjola@nokia.com>
   7 * DMA channel linking for 1610 by Samuel Ortiz <samuel.ortiz@nokia.com>
   8 * Graphics DMA and LCD DMA graphics tranformations
   9 * by Imre Deak <imre.deak@nokia.com>
  10 * OMAP2/3 support Copyright (C) 2004-2007 Texas Instruments, Inc.
  11 * Some functions based on earlier dma-omap.c Copyright (C) 2001 RidgeRun, Inc.
  12 *
  13 * Copyright (C) 2009 Texas Instruments
  14 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
  15 *
  16 * Copyright (C) 2010 Texas Instruments Incorporated - https://www.ti.com/
  17 * Converted DMA library into platform driver
  18 *      - G, Manjunath Kondaiah <manjugk@ti.com>
  19 */
  20
  21#include <linux/err.h>
  22#include <linux/io.h>
  23#include <linux/slab.h>
  24#include <linux/module.h>
  25#include <linux/init.h>
  26#include <linux/device.h>
  27#include <linux/dma-mapping.h>
  28#include <linux/dmaengine.h>
  29#include <linux/of.h>
  30#include <linux/omap-dma.h>
  31
  32#include "soc.h"
  33
  34static const struct omap_dma_reg reg_map[] = {
  35        [REVISION]      = { 0x0000, 0x00, OMAP_DMA_REG_32BIT },
  36        [GCR]           = { 0x0078, 0x00, OMAP_DMA_REG_32BIT },
  37        [IRQSTATUS_L0]  = { 0x0008, 0x00, OMAP_DMA_REG_32BIT },
  38        [IRQSTATUS_L1]  = { 0x000c, 0x00, OMAP_DMA_REG_32BIT },
  39        [IRQSTATUS_L2]  = { 0x0010, 0x00, OMAP_DMA_REG_32BIT },
  40        [IRQSTATUS_L3]  = { 0x0014, 0x00, OMAP_DMA_REG_32BIT },
  41        [IRQENABLE_L0]  = { 0x0018, 0x00, OMAP_DMA_REG_32BIT },
  42        [IRQENABLE_L1]  = { 0x001c, 0x00, OMAP_DMA_REG_32BIT },
  43        [IRQENABLE_L2]  = { 0x0020, 0x00, OMAP_DMA_REG_32BIT },
  44        [IRQENABLE_L3]  = { 0x0024, 0x00, OMAP_DMA_REG_32BIT },
  45        [SYSSTATUS]     = { 0x0028, 0x00, OMAP_DMA_REG_32BIT },
  46        [OCP_SYSCONFIG] = { 0x002c, 0x00, OMAP_DMA_REG_32BIT },
  47        [CAPS_0]        = { 0x0064, 0x00, OMAP_DMA_REG_32BIT },
  48        [CAPS_2]        = { 0x006c, 0x00, OMAP_DMA_REG_32BIT },
  49        [CAPS_3]        = { 0x0070, 0x00, OMAP_DMA_REG_32BIT },
  50        [CAPS_4]        = { 0x0074, 0x00, OMAP_DMA_REG_32BIT },
  51
  52        /* Common register offsets */
  53        [CCR]           = { 0x0080, 0x60, OMAP_DMA_REG_32BIT },
  54        [CLNK_CTRL]     = { 0x0084, 0x60, OMAP_DMA_REG_32BIT },
  55        [CICR]          = { 0x0088, 0x60, OMAP_DMA_REG_32BIT },
  56        [CSR]           = { 0x008c, 0x60, OMAP_DMA_REG_32BIT },
  57        [CSDP]          = { 0x0090, 0x60, OMAP_DMA_REG_32BIT },
  58        [CEN]           = { 0x0094, 0x60, OMAP_DMA_REG_32BIT },
  59        [CFN]           = { 0x0098, 0x60, OMAP_DMA_REG_32BIT },
  60        [CSEI]          = { 0x00a4, 0x60, OMAP_DMA_REG_32BIT },
  61        [CSFI]          = { 0x00a8, 0x60, OMAP_DMA_REG_32BIT },
  62        [CDEI]          = { 0x00ac, 0x60, OMAP_DMA_REG_32BIT },
  63        [CDFI]          = { 0x00b0, 0x60, OMAP_DMA_REG_32BIT },
  64        [CSAC]          = { 0x00b4, 0x60, OMAP_DMA_REG_32BIT },
  65        [CDAC]          = { 0x00b8, 0x60, OMAP_DMA_REG_32BIT },
  66
  67        /* Channel specific register offsets */
  68        [CSSA]          = { 0x009c, 0x60, OMAP_DMA_REG_32BIT },
  69        [CDSA]          = { 0x00a0, 0x60, OMAP_DMA_REG_32BIT },
  70        [CCEN]          = { 0x00bc, 0x60, OMAP_DMA_REG_32BIT },
  71        [CCFN]          = { 0x00c0, 0x60, OMAP_DMA_REG_32BIT },
  72        [COLOR]         = { 0x00c4, 0x60, OMAP_DMA_REG_32BIT },
  73
  74        /* OMAP4 specific registers */
  75        [CDP]           = { 0x00d0, 0x60, OMAP_DMA_REG_32BIT },
  76        [CNDP]          = { 0x00d4, 0x60, OMAP_DMA_REG_32BIT },
  77        [CCDN]          = { 0x00d8, 0x60, OMAP_DMA_REG_32BIT },
  78};
  79
  80static unsigned configure_dma_errata(void)
  81{
  82        unsigned errata = 0;
  83
  84        /*
  85         * Errata applicable for OMAP2430ES1.0 and all omap2420
  86         *
  87         * I.
  88         * Erratum ID: Not Available
  89         * Inter Frame DMA buffering issue DMA will wrongly
  90         * buffer elements if packing and bursting is enabled. This might
  91         * result in data gets stalled in FIFO at the end of the block.
  92         * Workaround: DMA channels must have BUFFERING_DISABLED bit set to
  93         * guarantee no data will stay in the DMA FIFO in case inter frame
  94         * buffering occurs
  95         *
  96         * II.
  97         * Erratum ID: Not Available
  98         * DMA may hang when several channels are used in parallel
  99         * In the following configuration, DMA channel hanging can occur:
 100         * a. Channel i, hardware synchronized, is enabled
 101         * b. Another channel (Channel x), software synchronized, is enabled.
 102         * c. Channel i is disabled before end of transfer
 103         * d. Channel i is reenabled.
 104         * e. Steps 1 to 4 are repeated a certain number of times.
 105         * f. A third channel (Channel y), software synchronized, is enabled.
 106         * Channel x and Channel y may hang immediately after step 'f'.
 107         * Workaround:
 108         * For any channel used - make sure NextLCH_ID is set to the value j.
 109         */
 110        if (cpu_is_omap2420() || (cpu_is_omap2430() &&
 111                                (omap_type() == OMAP2430_REV_ES1_0))) {
 112
 113                SET_DMA_ERRATA(DMA_ERRATA_IFRAME_BUFFERING);
 114                SET_DMA_ERRATA(DMA_ERRATA_PARALLEL_CHANNELS);
 115        }
 116
 117        /*
 118         * Erratum ID: i378: OMAP2+: sDMA Channel is not disabled
 119         * after a transaction error.
 120         * Workaround: SW should explicitely disable the channel.
 121         */
 122        if (cpu_class_is_omap2())
 123                SET_DMA_ERRATA(DMA_ERRATA_i378);
 124
 125        /*
 126         * Erratum ID: i541: sDMA FIFO draining does not finish
 127         * If sDMA channel is disabled on the fly, sDMA enters standby even
 128         * through FIFO Drain is still in progress
 129         * Workaround: Put sDMA in NoStandby more before a logical channel is
 130         * disabled, then put it back to SmartStandby right after the channel
 131         * finishes FIFO draining.
 132         */
 133        if (cpu_is_omap34xx())
 134                SET_DMA_ERRATA(DMA_ERRATA_i541);
 135
 136        /*
 137         * Erratum ID: i88 : Special programming model needed to disable DMA
 138         * before end of block.
 139         * Workaround: software must ensure that the DMA is configured in No
 140         * Standby mode(DMAx_OCP_SYSCONFIG.MIDLEMODE = "01")
 141         */
 142        if (omap_type() == OMAP3430_REV_ES1_0)
 143                SET_DMA_ERRATA(DMA_ERRATA_i88);
 144
 145        /*
 146         * Erratum 3.2/3.3: sometimes 0 is returned if CSAC/CDAC is
 147         * read before the DMA controller finished disabling the channel.
 148         */
 149        SET_DMA_ERRATA(DMA_ERRATA_3_3);
 150
 151        /*
 152         * Erratum ID: Not Available
 153         * A bug in ROM code leaves IRQ status for channels 0 and 1 uncleared
 154         * after secure sram context save and restore.
 155         * Work around: Hence we need to manually clear those IRQs to avoid
 156         * spurious interrupts. This affects only secure devices.
 157         */
 158        if (cpu_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
 159                SET_DMA_ERRATA(DMA_ROMCODE_BUG);
 160
 161        return errata;
 162}
 163
 164static const struct dma_slave_map omap24xx_sdma_dt_map[] = {
 165        /* external DMA requests when tusb6010 is used */
 166        { "musb-hdrc.1.auto", "dmareq0", SDMA_FILTER_PARAM(2) },
 167        { "musb-hdrc.1.auto", "dmareq1", SDMA_FILTER_PARAM(3) },
 168        { "musb-hdrc.1.auto", "dmareq2", SDMA_FILTER_PARAM(14) }, /* OMAP2420 only */
 169        { "musb-hdrc.1.auto", "dmareq3", SDMA_FILTER_PARAM(15) }, /* OMAP2420 only */
 170        { "musb-hdrc.1.auto", "dmareq4", SDMA_FILTER_PARAM(16) }, /* OMAP2420 only */
 171        { "musb-hdrc.1.auto", "dmareq5", SDMA_FILTER_PARAM(64) }, /* OMAP2420 only */
 172};
 173
 174static struct omap_dma_dev_attr dma_attr = {
 175        .dev_caps = RESERVE_CHANNEL | DMA_LINKED_LCH | GLOBAL_PRIORITY |
 176                    IS_CSSA_32 | IS_CDSA_32,
 177        .lch_count = 32,
 178};
 179
 180struct omap_system_dma_plat_info dma_plat_info = {
 181        .reg_map        = reg_map,
 182        .channel_stride = 0x60,
 183        .dma_attr       = &dma_attr,
 184};
 185
 186/* One time initializations */
 187static int __init omap2_system_dma_init(void)
 188{
 189        dma_plat_info.errata = configure_dma_errata();
 190
 191        if (soc_is_omap24xx()) {
 192                /* DMA slave map for drivers not yet converted to DT */
 193                dma_plat_info.slave_map = omap24xx_sdma_dt_map;
 194                dma_plat_info.slavecnt = ARRAY_SIZE(omap24xx_sdma_dt_map);
 195        }
 196
 197        if (!soc_is_omap242x())
 198                dma_attr.dev_caps |= IS_RW_PRIORITY;
 199
 200        if (soc_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
 201                dma_attr.dev_caps |= HS_CHANNELS_RESERVED;
 202
 203        return 0;
 204}
 205omap_arch_initcall(omap2_system_dma_init);
 206