1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (C) 2013,2018,2020-2021 Intel Corporation 3 4 #include <linux/bitops.h> 5 #include <linux/dmaengine.h> 6 #include <linux/errno.h> 7 #include <linux/io.h> 8 #include <linux/pci.h> 9 #include <linux/slab.h> 10 #include <linux/types.h> 11 12 #include "internal.h" 13 14 #define DMA_CTL_CH(x) (0x1000 + (x) * 4) 15 #define DMA_SRC_ADDR_FILLIN(x) (0x1100 + (x) * 4) 16 #define DMA_DST_ADDR_FILLIN(x) (0x1200 + (x) * 4) 17 #define DMA_XBAR_SEL(x) (0x1300 + (x) * 4) 18 #define DMA_REGACCESS_CHID_CFG (0x1400) 19 20 #define CTL_CH_TRANSFER_MODE_MASK GENMASK(1, 0) 21 #define CTL_CH_TRANSFER_MODE_S2S 0 22 #define CTL_CH_TRANSFER_MODE_S2D 1 23 #define CTL_CH_TRANSFER_MODE_D2S 2 24 #define CTL_CH_TRANSFER_MODE_D2D 3 25 #define CTL_CH_RD_RS_MASK GENMASK(4, 3) 26 #define CTL_CH_WR_RS_MASK GENMASK(6, 5) 27 #define CTL_CH_RD_NON_SNOOP_BIT BIT(8) 28 #define CTL_CH_WR_NON_SNOOP_BIT BIT(9) 29 30 #define XBAR_SEL_DEVID_MASK GENMASK(15, 0) 31 #define XBAR_SEL_RX_TX_BIT BIT(16) 32 #define XBAR_SEL_RX_TX_SHIFT 16 33 34 #define REGACCESS_CHID_MASK GENMASK(2, 0) 35 36 static unsigned int idma32_get_slave_devfn(struct dw_dma_chan *dwc) 37 { 38 struct device *slave = dwc->chan.slave; 39 40 if (!slave || !dev_is_pci(slave)) 41 return 0; 42 43 return to_pci_dev(slave)->devfn; 44 } 45 46 static void idma32_initialize_chan_xbar(struct dw_dma_chan *dwc) 47 { 48 struct dw_dma *dw = to_dw_dma(dwc->chan.device); 49 void __iomem *misc = __dw_regs(dw); 50 u32 cfghi = 0, cfglo = 0; 51 u8 dst_id, src_id; 52 u32 value; 53 54 /* DMA Channel ID Configuration register must be programmed first */ 55 value = readl(misc + DMA_REGACCESS_CHID_CFG); 56 57 value &= ~REGACCESS_CHID_MASK; 58 value |= dwc->chan.chan_id; 59 60 writel(value, misc + DMA_REGACCESS_CHID_CFG); 61 62 /* Configure channel attributes */ 63 value = readl(misc + DMA_CTL_CH(dwc->chan.chan_id)); 64 65 value &= ~(CTL_CH_RD_NON_SNOOP_BIT | CTL_CH_WR_NON_SNOOP_BIT); 66 value &= ~(CTL_CH_RD_RS_MASK | CTL_CH_WR_RS_MASK); 67 value &= ~CTL_CH_TRANSFER_MODE_MASK; 68 69 switch (dwc->direction) { 70 case DMA_MEM_TO_DEV: 71 value |= CTL_CH_TRANSFER_MODE_D2S; 72 value |= CTL_CH_WR_NON_SNOOP_BIT; 73 break; 74 case DMA_DEV_TO_MEM: 75 value |= CTL_CH_TRANSFER_MODE_S2D; 76 value |= CTL_CH_RD_NON_SNOOP_BIT; 77 break; 78 default: 79 /* 80 * Memory-to-Memory and Device-to-Device are ignored for now. 81 * 82 * For Memory-to-Memory transfers we would need to set mode 83 * and disable snooping on both sides. 84 */ 85 return; 86 } 87 88 writel(value, misc + DMA_CTL_CH(dwc->chan.chan_id)); 89 90 /* Configure crossbar selection */ 91 value = readl(misc + DMA_XBAR_SEL(dwc->chan.chan_id)); 92 93 /* DEVFN selection */ 94 value &= ~XBAR_SEL_DEVID_MASK; 95 value |= idma32_get_slave_devfn(dwc); 96 97 switch (dwc->direction) { 98 case DMA_MEM_TO_DEV: 99 value |= XBAR_SEL_RX_TX_BIT; 100 break; 101 case DMA_DEV_TO_MEM: 102 value &= ~XBAR_SEL_RX_TX_BIT; 103 break; 104 default: 105 /* Memory-to-Memory and Device-to-Device are ignored for now */ 106 return; 107 } 108 109 writel(value, misc + DMA_XBAR_SEL(dwc->chan.chan_id)); 110 111 /* Configure DMA channel low and high registers */ 112 switch (dwc->direction) { 113 case DMA_MEM_TO_DEV: 114 dst_id = dwc->chan.chan_id; 115 src_id = dwc->dws.src_id; 116 break; 117 case DMA_DEV_TO_MEM: 118 dst_id = dwc->dws.dst_id; 119 src_id = dwc->chan.chan_id; 120 break; 121 default: 122 /* Memory-to-Memory and Device-to-Device are ignored for now */ 123 return; 124 } 125 126 /* Set default burst alignment */ 127 cfglo |= IDMA32C_CFGL_DST_BURST_ALIGN | IDMA32C_CFGL_SRC_BURST_ALIGN; 128 129 /* Low 4 bits of the request lines */ 130 cfghi |= IDMA32C_CFGH_DST_PER(dst_id & 0xf); 131 cfghi |= IDMA32C_CFGH_SRC_PER(src_id & 0xf); 132 133 /* Request line extension (2 bits) */ 134 cfghi |= IDMA32C_CFGH_DST_PER_EXT(dst_id >> 4 & 0x3); 135 cfghi |= IDMA32C_CFGH_SRC_PER_EXT(src_id >> 4 & 0x3); 136 137 channel_writel(dwc, CFG_LO, cfglo); 138 channel_writel(dwc, CFG_HI, cfghi); 139 } 140 141 static void idma32_initialize_chan_generic(struct dw_dma_chan *dwc) 142 { 143 u32 cfghi = 0; 144 u32 cfglo = 0; 145 146 /* Set default burst alignment */ 147 cfglo |= IDMA32C_CFGL_DST_BURST_ALIGN | IDMA32C_CFGL_SRC_BURST_ALIGN; 148 149 /* Low 4 bits of the request lines */ 150 cfghi |= IDMA32C_CFGH_DST_PER(dwc->dws.dst_id & 0xf); 151 cfghi |= IDMA32C_CFGH_SRC_PER(dwc->dws.src_id & 0xf); 152 153 /* Request line extension (2 bits) */ 154 cfghi |= IDMA32C_CFGH_DST_PER_EXT(dwc->dws.dst_id >> 4 & 0x3); 155 cfghi |= IDMA32C_CFGH_SRC_PER_EXT(dwc->dws.src_id >> 4 & 0x3); 156 157 channel_writel(dwc, CFG_LO, cfglo); 158 channel_writel(dwc, CFG_HI, cfghi); 159 } 160 161 static void idma32_suspend_chan(struct dw_dma_chan *dwc, bool drain) 162 { 163 u32 cfglo = channel_readl(dwc, CFG_LO); 164 165 if (drain) 166 cfglo |= IDMA32C_CFGL_CH_DRAIN; 167 168 channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP); 169 } 170 171 static void idma32_resume_chan(struct dw_dma_chan *dwc, bool drain) 172 { 173 u32 cfglo = channel_readl(dwc, CFG_LO); 174 175 if (drain) 176 cfglo &= ~IDMA32C_CFGL_CH_DRAIN; 177 178 channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP); 179 } 180 181 static u32 idma32_bytes2block(struct dw_dma_chan *dwc, 182 size_t bytes, unsigned int width, size_t *len) 183 { 184 u32 block; 185 186 if (bytes > dwc->block_size) { 187 block = dwc->block_size; 188 *len = dwc->block_size; 189 } else { 190 block = bytes; 191 *len = bytes; 192 } 193 194 return block; 195 } 196 197 static size_t idma32_block2bytes(struct dw_dma_chan *dwc, u32 block, u32 width) 198 { 199 return IDMA32C_CTLH_BLOCK_TS(block); 200 } 201 202 static inline u8 idma32_encode_maxburst(u32 maxburst) 203 { 204 return maxburst > 1 ? fls(maxburst) - 1 : 0; 205 } 206 207 static u32 idma32_prepare_ctllo(struct dw_dma_chan *dwc) 208 { 209 struct dma_slave_config *sconfig = &dwc->dma_sconfig; 210 u8 smsize = 0, dmsize = 0; 211 212 if (dwc->direction == DMA_MEM_TO_DEV) 213 dmsize = idma32_encode_maxburst(sconfig->dst_maxburst); 214 else if (dwc->direction == DMA_DEV_TO_MEM) 215 smsize = idma32_encode_maxburst(sconfig->src_maxburst); 216 217 return DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN | 218 DWC_CTLL_DST_MSIZE(dmsize) | DWC_CTLL_SRC_MSIZE(smsize); 219 } 220 221 static void idma32_set_device_name(struct dw_dma *dw, int id) 222 { 223 snprintf(dw->name, sizeof(dw->name), "idma32:dmac%d", id); 224 } 225 226 /* 227 * Program FIFO size of channels. 228 * 229 * By default full FIFO (512 bytes) is assigned to channel 0. Here we 230 * slice FIFO on equal parts between channels. 231 */ 232 static void idma32_fifo_partition(struct dw_dma *dw) 233 { 234 u64 value = IDMA32C_FP_PSIZE_CH0(64) | IDMA32C_FP_PSIZE_CH1(64) | 235 IDMA32C_FP_UPDATE; 236 u64 fifo_partition = 0; 237 238 /* Fill FIFO_PARTITION low bits (Channels 0..1, 4..5) */ 239 fifo_partition |= value << 0; 240 241 /* Fill FIFO_PARTITION high bits (Channels 2..3, 6..7) */ 242 fifo_partition |= value << 32; 243 244 /* Program FIFO Partition registers - 64 bytes per channel */ 245 idma32_writeq(dw, FIFO_PARTITION1, fifo_partition); 246 idma32_writeq(dw, FIFO_PARTITION0, fifo_partition); 247 } 248 249 static void idma32_disable(struct dw_dma *dw) 250 { 251 do_dw_dma_off(dw); 252 idma32_fifo_partition(dw); 253 } 254 255 static void idma32_enable(struct dw_dma *dw) 256 { 257 idma32_fifo_partition(dw); 258 do_dw_dma_on(dw); 259 } 260 261 int idma32_dma_probe(struct dw_dma_chip *chip) 262 { 263 struct dw_dma *dw; 264 265 dw = devm_kzalloc(chip->dev, sizeof(*dw), GFP_KERNEL); 266 if (!dw) 267 return -ENOMEM; 268 269 /* Channel operations */ 270 if (chip->pdata->quirks & DW_DMA_QUIRK_XBAR_PRESENT) 271 dw->initialize_chan = idma32_initialize_chan_xbar; 272 else 273 dw->initialize_chan = idma32_initialize_chan_generic; 274 dw->suspend_chan = idma32_suspend_chan; 275 dw->resume_chan = idma32_resume_chan; 276 dw->prepare_ctllo = idma32_prepare_ctllo; 277 dw->bytes2block = idma32_bytes2block; 278 dw->block2bytes = idma32_block2bytes; 279 280 /* Device operations */ 281 dw->set_device_name = idma32_set_device_name; 282 dw->disable = idma32_disable; 283 dw->enable = idma32_enable; 284 285 chip->dw = dw; 286 return do_dma_probe(chip); 287 } 288 EXPORT_SYMBOL_GPL(idma32_dma_probe); 289 290 int idma32_dma_remove(struct dw_dma_chip *chip) 291 { 292 return do_dma_remove(chip); 293 } 294 EXPORT_SYMBOL_GPL(idma32_dma_remove); 295