drivers/dma/ti/dma-crossbar.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com
   4  *  Author: Peter Ujfalusi <peter.ujfalusi@ti.com>
   5  */
   6 #include <linux/slab.h>
   7 #include <linux/err.h>
   8 #include <linux/init.h>
   9 #include <linux/list.h>
  10 #include <linux/io.h>
  11 #include <linux/of_address.h>
  12 #include <linux/of_device.h>
  13 #include <linux/of_dma.h>
  14
  15 #define TI_XBAR_DRA7            0
  16 #define TI_XBAR_AM335X          1
  17 static const u32 ti_xbar_type[] = {
  18         [TI_XBAR_DRA7] = TI_XBAR_DRA7,
  19         [TI_XBAR_AM335X] = TI_XBAR_AM335X,
  20 };
  21
  22 static const struct of_device_id ti_dma_xbar_match[] = {
  23         {
  24                 .compatible = "ti,dra7-dma-crossbar",
  25                 .data = &ti_xbar_type[TI_XBAR_DRA7],
  26         },
  27         {
  28                 .compatible = "ti,am335x-edma-crossbar",
  29                 .data = &ti_xbar_type[TI_XBAR_AM335X],
  30         },
  31         {},
  32 };
  33
  34 /* Crossbar on AM335x/AM437x family */
  35 #define TI_AM335X_XBAR_LINES    64
  36
  37 struct ti_am335x_xbar_data {
  38         void __iomem *iomem;
  39
  40         struct dma_router dmarouter;
  41
  42         u32 xbar_events; /* maximum number of events to select in xbar */
  43         u32 dma_requests; /* number of DMA requests on eDMA */
  44 };
  45
  46 struct ti_am335x_xbar_map {
  47         u16 dma_line;
  48         u8 mux_val;
  49 };
  50
  51 static inline void ti_am335x_xbar_write(void __iomem *iomem, int event, u8 val)
  52 {
  53         /*
  54          * TPCC_EVT_MUX_60_63 register layout is different than the
  55          * rest, in the sense, that event 63 is mapped to lowest byte
  56          * and event 60 is mapped to highest, handle it separately.
  57          */
  58         if (event >= 60 && event <= 63)
  59                 writeb_relaxed(val, iomem + (63 - event % 4));
  60         else
  61                 writeb_relaxed(val, iomem + event);
  62 }
  63
  64 static void ti_am335x_xbar_free(struct device *dev, void *route_data)
  65 {
  66         struct ti_am335x_xbar_data *xbar = dev_get_drvdata(dev);
  67         struct ti_am335x_xbar_map *map = route_data;
  68
  69         dev_dbg(dev, "Unmapping XBAR event %u on channel %u\n",
  70                 map->mux_val, map->dma_line);
  71
  72         ti_am335x_xbar_write(xbar->iomem, map->dma_line, 0);
  73         kfree(map);
  74 }
  75
  76 static void *ti_am335x_xbar_route_allocate(struct of_phandle_args *dma_spec,
  77                                            struct of_dma *ofdma)
  78 {
  79         struct platform_device *pdev = of_find_device_by_node(ofdma->of_node);
  80         struct ti_am335x_xbar_data *xbar = platform_get_drvdata(pdev);
  81         struct ti_am335x_xbar_map *map;
  82
  83         if (dma_spec->args_count != 3)
  84                 return ERR_PTR(-EINVAL);
  85
  86         if (dma_spec->args[2] >= xbar->xbar_events) {
  87                 dev_err(&pdev->dev, "Invalid XBAR event number: %d\n",
  88                         dma_spec->args[2]);
  89                 return ERR_PTR(-EINVAL);
  90         }
  91
  92         if (dma_spec->args[0] >= xbar->dma_requests) {
  93                 dev_err(&pdev->dev, "Invalid DMA request line number: %d\n",
  94                         dma_spec->args[0]);
  95                 return ERR_PTR(-EINVAL);
  96         }
  97
  98         /* The of_node_put() will be done in the core for the node */
  99         dma_spec->np = of_parse_phandle(ofdma->of_node, "dma-masters", 0);
 100         if (!dma_spec->np) {
 101                 dev_err(&pdev->dev, "Can't get DMA master\n");
 102                 return ERR_PTR(-EINVAL);
 103         }
 104
 105         map = kzalloc(sizeof(*map), GFP_KERNEL);
 106         if (!map) {
 107                 of_node_put(dma_spec->np);
 108                 return ERR_PTR(-ENOMEM);
 109         }
 110
 111         map->dma_line = (u16)dma_spec->args[0];
 112         map->mux_val = (u8)dma_spec->args[2];
 113
 114         dma_spec->args[2] = 0;
 115         dma_spec->args_count = 2;
 116
 117         dev_dbg(&pdev->dev, "Mapping XBAR event%u to DMA%u\n",
 118                 map->mux_val, map->dma_line);
 119
 120         ti_am335x_xbar_write(xbar->iomem, map->dma_line, map->mux_val);
 121
 122         return map;
 123 }
 124
 125 static const struct of_device_id ti_am335x_master_match[] __maybe_unused = {
 126         { .compatible = "ti,edma3-tpcc", },
 127         {},
 128 };
 129
 130 static int ti_am335x_xbar_probe(struct platform_device *pdev)
 131 {
 132         struct device_node *node = pdev->dev.of_node;
 133         const struct of_device_id *match;
 134         struct device_node *dma_node;
 135         struct ti_am335x_xbar_data *xbar;
 136         void __iomem *iomem;
 137         int i, ret;
 138
 139         if (!node)
 140                 return -ENODEV;
 141
 142         xbar = devm_kzalloc(&pdev->dev, sizeof(*xbar), GFP_KERNEL);
 143         if (!xbar)
 144                 return -ENOMEM;
 145
 146         dma_node = of_parse_phandle(node, "dma-masters", 0);
 147         if (!dma_node) {
 148                 dev_err(&pdev->dev, "Can't get DMA master node\n");
 149                 return -ENODEV;
 150         }
 151
 152         match = of_match_node(ti_am335x_master_match, dma_node);
 153         if (!match) {
 154                 dev_err(&pdev->dev, "DMA master is not supported\n");
 155                 of_node_put(dma_node);
 156                 return -EINVAL;
 157         }
 158
 159         if (of_property_read_u32(dma_node, "dma-requests",
 160                                  &xbar->dma_requests)) {
 161                 dev_info(&pdev->dev,
 162                          "Missing XBAR output information, using %u.\n",
 163                          TI_AM335X_XBAR_LINES);
 164                 xbar->dma_requests = TI_AM335X_XBAR_LINES;
 165         }
 166         of_node_put(dma_node);
 167
 168         if (of_property_read_u32(node, "dma-requests", &xbar->xbar_events)) {
 169                 dev_info(&pdev->dev,
 170                          "Missing XBAR input information, using %u.\n",
 171                          TI_AM335X_XBAR_LINES);
 172                 xbar->xbar_events = TI_AM335X_XBAR_LINES;
 173         }
 174
 175         iomem = devm_platform_ioremap_resource(pdev, 0);
 176         if (IS_ERR(iomem))
 177                 return PTR_ERR(iomem);
 178
 179         xbar->iomem = iomem;
 180
 181         xbar->dmarouter.dev = &pdev->dev;
 182         xbar->dmarouter.route_free = ti_am335x_xbar_free;
 183
 184         platform_set_drvdata(pdev, xbar);
 185
 186         /* Reset the crossbar */
 187         for (i = 0; i < xbar->dma_requests; i++)
 188                 ti_am335x_xbar_write(xbar->iomem, i, 0);
 189
 190         ret = of_dma_router_register(node, ti_am335x_xbar_route_allocate,
 191                                      &xbar->dmarouter);
 192
 193         return ret;
 194 }
 195
 196 /* Crossbar on DRA7xx family */
 197 #define TI_DRA7_XBAR_OUTPUTS    127
 198 #define TI_DRA7_XBAR_INPUTS     256
 199
 200 struct ti_dra7_xbar_data {
 201         void __iomem *iomem;
 202
 203         struct dma_router dmarouter;
 204         struct mutex mutex;
 205         unsigned long *dma_inuse;
 206
 207         u16 safe_val; /* Value to rest the crossbar lines */
 208         u32 xbar_requests; /* number of DMA requests connected to XBAR */
 209         u32 dma_requests; /* number of DMA requests forwarded to DMA */
 210         u32 dma_offset;
 211 };
 212
 213 struct ti_dra7_xbar_map {
 214         u16 xbar_in;
 215         int xbar_out;
 216 };
 217
 218 static inline void ti_dra7_xbar_write(void __iomem *iomem, int xbar, u16 val)
 219 {
 220         writew_relaxed(val, iomem + (xbar * 2));
 221 }
 222
 223 static void ti_dra7_xbar_free(struct device *dev, void *route_data)
 224 {
 225         struct ti_dra7_xbar_data *xbar = dev_get_drvdata(dev);
 226         struct ti_dra7_xbar_map *map = route_data;
 227
 228         dev_dbg(dev, "Unmapping XBAR%u (was routed to %d)\n",
 229                 map->xbar_in, map->xbar_out);
 230
 231         ti_dra7_xbar_write(xbar->iomem, map->xbar_out, xbar->safe_val);
 232         mutex_lock(&xbar->mutex);
 233         clear_bit(map->xbar_out, xbar->dma_inuse);
 234         mutex_unlock(&xbar->mutex);
 235         kfree(map);
 236 }
 237
 238 static void *ti_dra7_xbar_route_allocate(struct of_phandle_args *dma_spec,
 239                                          struct of_dma *ofdma)
 240 {
 241         struct platform_device *pdev = of_find_device_by_node(ofdma->of_node);
 242         struct ti_dra7_xbar_data *xbar = platform_get_drvdata(pdev);
 243         struct ti_dra7_xbar_map *map;
 244
 245         if (dma_spec->args[0] >= xbar->xbar_requests) {
 246                 dev_err(&pdev->dev, "Invalid XBAR request number: %d\n",
 247                         dma_spec->args[0]);
 248                 put_device(&pdev->dev);
 249                 return ERR_PTR(-EINVAL);
 250         }
 251
 252         /* The of_node_put() will be done in the core for the node */
 253         dma_spec->np = of_parse_phandle(ofdma->of_node, "dma-masters", 0);
 254         if (!dma_spec->np) {
 255                 dev_err(&pdev->dev, "Can't get DMA master\n");
 256                 put_device(&pdev->dev);
 257                 return ERR_PTR(-EINVAL);
 258         }
 259
 260         map = kzalloc(sizeof(*map), GFP_KERNEL);
 261         if (!map) {
 262                 of_node_put(dma_spec->np);
 263                 put_device(&pdev->dev);
 264                 return ERR_PTR(-ENOMEM);
 265         }
 266
 267         mutex_lock(&xbar->mutex);
 268         map->xbar_out = find_first_zero_bit(xbar->dma_inuse,
 269                                             xbar->dma_requests);
 270         if (map->xbar_out == xbar->dma_requests) {
 271                 mutex_unlock(&xbar->mutex);
 272                 dev_err(&pdev->dev, "Run out of free DMA requests\n");
 273                 kfree(map);
 274                 of_node_put(dma_spec->np);
 275                 put_device(&pdev->dev);
 276                 return ERR_PTR(-ENOMEM);
 277         }
 278         set_bit(map->xbar_out, xbar->dma_inuse);
 279         mutex_unlock(&xbar->mutex);
 280
 281         map->xbar_in = (u16)dma_spec->args[0];
 282
 283         dma_spec->args[0] = map->xbar_out + xbar->dma_offset;
 284
 285         dev_dbg(&pdev->dev, "Mapping XBAR%u to DMA%d\n",
 286                 map->xbar_in, map->xbar_out);
 287
 288         ti_dra7_xbar_write(xbar->iomem, map->xbar_out, map->xbar_in);
 289
 290         return map;
 291 }
 292
 293 #define TI_XBAR_EDMA_OFFSET     0
 294 #define TI_XBAR_SDMA_OFFSET     1
 295 static const u32 ti_dma_offset[] = {
 296         [TI_XBAR_EDMA_OFFSET] = 0,
 297         [TI_XBAR_SDMA_OFFSET] = 1,
 298 };
 299
 300 static const struct of_device_id ti_dra7_master_match[] __maybe_unused = {
 301         {
 302                 .compatible = "ti,omap4430-sdma",
 303                 .data = &ti_dma_offset[TI_XBAR_SDMA_OFFSET],
 304         },
 305         {
 306                 .compatible = "ti,edma3",
 307                 .data = &ti_dma_offset[TI_XBAR_EDMA_OFFSET],
 308         },
 309         {
 310                 .compatible = "ti,edma3-tpcc",
 311                 .data = &ti_dma_offset[TI_XBAR_EDMA_OFFSET],
 312         },
 313         {},
 314 };
 315
 316 static inline void ti_dra7_xbar_reserve(int offset, int len, unsigned long *p)
 317 {
 318         for (; len > 0; len--)
 319                 set_bit(offset + (len - 1), p);
 320 }
 321
 322 static int ti_dra7_xbar_probe(struct platform_device *pdev)
 323 {
 324         struct device_node *node = pdev->dev.of_node;
 325         const struct of_device_id *match;
 326         struct device_node *dma_node;
 327         struct ti_dra7_xbar_data *xbar;
 328         struct property *prop;
 329         u32 safe_val;
 330         int sz;
 331         void __iomem *iomem;
 332         int i, ret;
 333
 334         if (!node)
 335                 return -ENODEV;
 336
 337         xbar = devm_kzalloc(&pdev->dev, sizeof(*xbar), GFP_KERNEL);
 338         if (!xbar)
 339                 return -ENOMEM;
 340
 341         dma_node = of_parse_phandle(node, "dma-masters", 0);
 342         if (!dma_node) {
 343                 dev_err(&pdev->dev, "Can't get DMA master node\n");
 344                 return -ENODEV;
 345         }
 346
 347         match = of_match_node(ti_dra7_master_match, dma_node);
 348         if (!match) {
 349                 dev_err(&pdev->dev, "DMA master is not supported\n");
 350                 of_node_put(dma_node);
 351                 return -EINVAL;
 352         }
 353
 354         if (of_property_read_u32(dma_node, "dma-requests",
 355                                  &xbar->dma_requests)) {
 356                 dev_info(&pdev->dev,
 357                          "Missing XBAR output information, using %u.\n",
 358                          TI_DRA7_XBAR_OUTPUTS);
 359                 xbar->dma_requests = TI_DRA7_XBAR_OUTPUTS;
 360         }
 361         of_node_put(dma_node);
 362
 363         xbar->dma_inuse = devm_kcalloc(&pdev->dev,
 364                                        BITS_TO_LONGS(xbar->dma_requests),
 365                                        sizeof(unsigned long), GFP_KERNEL);
 366         if (!xbar->dma_inuse)
 367                 return -ENOMEM;
 368
 369         if (of_property_read_u32(node, "dma-requests", &xbar->xbar_requests)) {
 370                 dev_info(&pdev->dev,
 371                          "Missing XBAR input information, using %u.\n",
 372                          TI_DRA7_XBAR_INPUTS);
 373                 xbar->xbar_requests = TI_DRA7_XBAR_INPUTS;
 374         }
 375
 376         if (!of_property_read_u32(node, "ti,dma-safe-map", &safe_val))
 377                 xbar->safe_val = (u16)safe_val;
 378
 379
 380         prop = of_find_property(node, "ti,reserved-dma-request-ranges", &sz);
 381         if (prop) {
 382                 const char pname[] = "ti,reserved-dma-request-ranges";
 383                 u32 (*rsv_events)[2];
 384                 size_t nelm = sz / sizeof(*rsv_events);
 385                 int i;
 386
 387                 if (!nelm)
 388                         return -EINVAL;
 389
 390                 rsv_events = kcalloc(nelm, sizeof(*rsv_events), GFP_KERNEL);
 391                 if (!rsv_events)
 392                         return -ENOMEM;
 393
 394                 ret = of_property_read_u32_array(node, pname, (u32 *)rsv_events,
 395                                                  nelm * 2);
 396                 if (ret) {
 397                         kfree(rsv_events);
 398                         return ret;
 399                 }
 400
 401                 for (i = 0; i < nelm; i++) {
 402                         ti_dra7_xbar_reserve(rsv_events[i][0], rsv_events[i][1],
 403                                              xbar->dma_inuse);
 404                 }
 405                 kfree(rsv_events);
 406         }
 407
 408         iomem = devm_platform_ioremap_resource(pdev, 0);
 409         if (IS_ERR(iomem))
 410                 return PTR_ERR(iomem);
 411
 412         xbar->iomem = iomem;
 413
 414         xbar->dmarouter.dev = &pdev->dev;
 415         xbar->dmarouter.route_free = ti_dra7_xbar_free;
 416         xbar->dma_offset = *(u32 *)match->data;
 417
 418         mutex_init(&xbar->mutex);
 419         platform_set_drvdata(pdev, xbar);
 420
 421         /* Reset the crossbar */
 422         for (i = 0; i < xbar->dma_requests; i++) {
 423                 if (!test_bit(i, xbar->dma_inuse))
 424                         ti_dra7_xbar_write(xbar->iomem, i, xbar->safe_val);
 425         }
 426
 427         ret = of_dma_router_register(node, ti_dra7_xbar_route_allocate,
 428                                      &xbar->dmarouter);
 429         if (ret) {
 430                 /* Restore the defaults for the crossbar */
 431                 for (i = 0; i < xbar->dma_requests; i++) {
 432                         if (!test_bit(i, xbar->dma_inuse))
 433                                 ti_dra7_xbar_write(xbar->iomem, i, i);
 434                 }
 435         }
 436
 437         return ret;
 438 }
 439
 440 static int ti_dma_xbar_probe(struct platform_device *pdev)
 441 {
 442         const struct of_device_id *match;
 443         int ret;
 444
 445         match = of_match_node(ti_dma_xbar_match, pdev->dev.of_node);
 446         if (unlikely(!match))
 447                 return -EINVAL;
 448
 449         switch (*(u32 *)match->data) {
 450         case TI_XBAR_DRA7:
 451                 ret = ti_dra7_xbar_probe(pdev);
 452                 break;
 453         case TI_XBAR_AM335X:
 454                 ret = ti_am335x_xbar_probe(pdev);
 455                 break;
 456         default:
 457                 dev_err(&pdev->dev, "Unsupported crossbar\n");
 458                 ret = -ENODEV;
 459                 break;
 460         }
 461
 462         return ret;
 463 }
 464
 465 static struct platform_driver ti_dma_xbar_driver = {
 466         .driver = {
 467                 .name = "ti-dma-crossbar",
 468                 .of_match_table = ti_dma_xbar_match,
 469         },
 470         .probe  = ti_dma_xbar_probe,
 471 };
 472
 473 static int omap_dmaxbar_init(void)
 474 {
 475         return platform_driver_register(&ti_dma_xbar_driver);
 476 }
 477 arch_initcall(omap_dmaxbar_init);