drivers/dma/dw/idma32.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (C) 2013,2018 Intel Corporation
   3
   4 #include <linux/bitops.h>
   5 #include <linux/dmaengine.h>
   6 #include <linux/errno.h>
   7 #include <linux/slab.h>
   8 #include <linux/types.h>
   9
  10 #include "internal.h"
  11
  12 static void idma32_initialize_chan(struct dw_dma_chan *dwc)
  13 {
  14         u32 cfghi = 0;
  15         u32 cfglo = 0;
  16
  17         /* Set default burst alignment */
  18         cfglo |= IDMA32C_CFGL_DST_BURST_ALIGN | IDMA32C_CFGL_SRC_BURST_ALIGN;
  19
  20         /* Low 4 bits of the request lines */
  21         cfghi |= IDMA32C_CFGH_DST_PER(dwc->dws.dst_id & 0xf);
  22         cfghi |= IDMA32C_CFGH_SRC_PER(dwc->dws.src_id & 0xf);
  23
  24         /* Request line extension (2 bits) */
  25         cfghi |= IDMA32C_CFGH_DST_PER_EXT(dwc->dws.dst_id >> 4 & 0x3);
  26         cfghi |= IDMA32C_CFGH_SRC_PER_EXT(dwc->dws.src_id >> 4 & 0x3);
  27
  28         channel_writel(dwc, CFG_LO, cfglo);
  29         channel_writel(dwc, CFG_HI, cfghi);
  30 }
  31
  32 static void idma32_suspend_chan(struct dw_dma_chan *dwc, bool drain)
  33 {
  34         u32 cfglo = channel_readl(dwc, CFG_LO);
  35
  36         if (drain)
  37                 cfglo |= IDMA32C_CFGL_CH_DRAIN;
  38
  39         channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
  40 }
  41
  42 static void idma32_resume_chan(struct dw_dma_chan *dwc, bool drain)
  43 {
  44         u32 cfglo = channel_readl(dwc, CFG_LO);
  45
  46         if (drain)
  47                 cfglo &= ~IDMA32C_CFGL_CH_DRAIN;
  48
  49         channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);
  50 }
  51
  52 static u32 idma32_bytes2block(struct dw_dma_chan *dwc,
  53                               size_t bytes, unsigned int width, size_t *len)
  54 {
  55         u32 block;
  56
  57         if (bytes > dwc->block_size) {
  58                 block = dwc->block_size;
  59                 *len = dwc->block_size;
  60         } else {
  61                 block = bytes;
  62                 *len = bytes;
  63         }
  64
  65         return block;
  66 }
  67
  68 static size_t idma32_block2bytes(struct dw_dma_chan *dwc, u32 block, u32 width)
  69 {
  70         return IDMA32C_CTLH_BLOCK_TS(block);
  71 }
  72
  73 static u32 idma32_prepare_ctllo(struct dw_dma_chan *dwc)
  74 {
  75         struct dma_slave_config *sconfig = &dwc->dma_sconfig;
  76         u8 smsize = (dwc->direction == DMA_DEV_TO_MEM) ? sconfig->src_maxburst : 0;
  77         u8 dmsize = (dwc->direction == DMA_MEM_TO_DEV) ? sconfig->dst_maxburst : 0;
  78
  79         return DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN |
  80                DWC_CTLL_DST_MSIZE(dmsize) | DWC_CTLL_SRC_MSIZE(smsize);
  81 }
  82
  83 static void idma32_encode_maxburst(struct dw_dma_chan *dwc, u32 *maxburst)
  84 {
  85         *maxburst = *maxburst > 1 ? fls(*maxburst) - 1 : 0;
  86 }
  87
  88 static void idma32_set_device_name(struct dw_dma *dw, int id)
  89 {
  90         snprintf(dw->name, sizeof(dw->name), "idma32:dmac%d", id);
  91 }
  92
  93 /*
  94  * Program FIFO size of channels.
  95  *
  96  * By default full FIFO (512 bytes) is assigned to channel 0. Here we
  97  * slice FIFO on equal parts between channels.
  98  */
  99 static void idma32_fifo_partition(struct dw_dma *dw)
 100 {
 101         u64 value = IDMA32C_FP_PSIZE_CH0(64) | IDMA32C_FP_PSIZE_CH1(64) |
 102                     IDMA32C_FP_UPDATE;
 103         u64 fifo_partition = 0;
 104
 105         /* Fill FIFO_PARTITION low bits (Channels 0..1, 4..5) */
 106         fifo_partition |= value << 0;
 107
 108         /* Fill FIFO_PARTITION high bits (Channels 2..3, 6..7) */
 109         fifo_partition |= value << 32;
 110
 111         /* Program FIFO Partition registers - 64 bytes per channel */
 112         idma32_writeq(dw, FIFO_PARTITION1, fifo_partition);
 113         idma32_writeq(dw, FIFO_PARTITION0, fifo_partition);
 114 }
 115
 116 static void idma32_disable(struct dw_dma *dw)
 117 {
 118         do_dw_dma_off(dw);
 119         idma32_fifo_partition(dw);
 120 }
 121
 122 static void idma32_enable(struct dw_dma *dw)
 123 {
 124         idma32_fifo_partition(dw);
 125         do_dw_dma_on(dw);
 126 }
 127
 128 int idma32_dma_probe(struct dw_dma_chip *chip)
 129 {
 130         struct dw_dma *dw;
 131
 132         dw = devm_kzalloc(chip->dev, sizeof(*dw), GFP_KERNEL);
 133         if (!dw)
 134                 return -ENOMEM;
 135
 136         /* Channel operations */
 137         dw->initialize_chan = idma32_initialize_chan;
 138         dw->suspend_chan = idma32_suspend_chan;
 139         dw->resume_chan = idma32_resume_chan;
 140         dw->prepare_ctllo = idma32_prepare_ctllo;
 141         dw->encode_maxburst = idma32_encode_maxburst;
 142         dw->bytes2block = idma32_bytes2block;
 143         dw->block2bytes = idma32_block2bytes;
 144
 145         /* Device operations */
 146         dw->set_device_name = idma32_set_device_name;
 147         dw->disable = idma32_disable;
 148         dw->enable = idma32_enable;
 149
 150         chip->dw = dw;
 151         return do_dma_probe(chip);
 152 }
 153 EXPORT_SYMBOL_GPL(idma32_dma_probe);
 154
 155 int idma32_dma_remove(struct dw_dma_chip *chip)
 156 {
 157         return do_dma_remove(chip);
 158 }
 159 EXPORT_SYMBOL_GPL(idma32_dma_remove);