1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * DMA support for Internal DMAC with SDHI SD/SDIO controller 4 * 5 * Copyright (C) 2016-19 Renesas Electronics Corporation 6 * Copyright (C) 2016-17 Horms Solutions, Simon Horman 7 * Copyright (C) 2018-19 Sang Engineering, Wolfram Sang 8 */ 9 10 #include <linux/bitops.h> 11 #include <linux/device.h> 12 #include <linux/dma-mapping.h> 13 #include <linux/io-64-nonatomic-hi-lo.h> 14 #include <linux/mfd/tmio.h> 15 #include <linux/mmc/host.h> 16 #include <linux/mod_devicetable.h> 17 #include <linux/module.h> 18 #include <linux/pagemap.h> 19 #include <linux/scatterlist.h> 20 #include <linux/sys_soc.h> 21 22 #include "renesas_sdhi.h" 23 #include "tmio_mmc.h" 24 25 #define DM_CM_DTRAN_MODE 0x820 26 #define DM_CM_DTRAN_CTRL 0x828 27 #define DM_CM_RST 0x830 28 #define DM_CM_INFO1 0x840 29 #define DM_CM_INFO1_MASK 0x848 30 #define DM_CM_INFO2 0x850 31 #define DM_CM_INFO2_MASK 0x858 32 #define DM_DTRAN_ADDR 0x880 33 34 /* DM_CM_DTRAN_MODE */ 35 #define DTRAN_MODE_CH_NUM_CH0 0 /* "downstream" = for write commands */ 36 #define DTRAN_MODE_CH_NUM_CH1 BIT(16) /* "upstream" = for read commands */ 37 #define DTRAN_MODE_BUS_WIDTH (BIT(5) | BIT(4)) 38 #define DTRAN_MODE_ADDR_MODE BIT(0) /* 1 = Increment address, 0 = Fixed */ 39 40 /* DM_CM_DTRAN_CTRL */ 41 #define DTRAN_CTRL_DM_START BIT(0) 42 43 /* DM_CM_RST */ 44 #define RST_DTRANRST1 BIT(9) 45 #define RST_DTRANRST0 BIT(8) 46 #define RST_RESERVED_BITS GENMASK_ULL(31, 0) 47 48 /* DM_CM_INFO1 and DM_CM_INFO1_MASK */ 49 #define INFO1_CLEAR 0 50 #define INFO1_MASK_CLEAR GENMASK_ULL(31, 0) 51 #define INFO1_DTRANEND1 BIT(17) 52 #define INFO1_DTRANEND0 BIT(16) 53 54 /* DM_CM_INFO2 and DM_CM_INFO2_MASK */ 55 #define INFO2_MASK_CLEAR GENMASK_ULL(31, 0) 56 #define INFO2_DTRANERR1 BIT(17) 57 #define INFO2_DTRANERR0 BIT(16) 58 59 enum renesas_sdhi_dma_cookie { 60 COOKIE_UNMAPPED, 61 COOKIE_PRE_MAPPED, 62 COOKIE_MAPPED, 63 }; 64 65 /* 66 * Specification of this driver: 67 * - host->chan_{rx,tx} will be used as a flag of enabling/disabling the dma 68 * - Since this SDHI DMAC register set has 16 but 32-bit width, we 69 * need a custom accessor. 70 */ 71 72 static unsigned long global_flags; 73 /* 74 * Workaround for avoiding to use RX DMAC by multiple channels. 75 * On R-Car H3 ES1.* and M3-W ES1.0, when multiple SDHI channels use 76 * RX DMAC simultaneously, sometimes hundreds of bytes data are not 77 * stored into the system memory even if the DMAC interrupt happened. 78 * So, this driver then uses one RX DMAC channel only. 79 */ 80 #define SDHI_INTERNAL_DMAC_ONE_RX_ONLY 0 81 #define SDHI_INTERNAL_DMAC_RX_IN_USE 1 82 83 /* RZ/A2 does not have the ADRR_MODE bit */ 84 #define SDHI_INTERNAL_DMAC_ADDR_MODE_FIXED_ONLY 2 85 86 /* Definitions for sampling clocks */ 87 static struct renesas_sdhi_scc rcar_gen3_scc_taps[] = { 88 { 89 .clk_rate = 0, 90 .tap = 0x00000300, 91 .tap_hs400_4tap = 0x00000100, 92 }, 93 }; 94 95 static const struct renesas_sdhi_of_data of_rza2_compatible = { 96 .tmio_flags = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL | 97 TMIO_MMC_HAVE_CBSY, 98 .tmio_ocr_mask = MMC_VDD_32_33, 99 .capabilities = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ | 100 MMC_CAP_CMD23, 101 .bus_shift = 2, 102 .scc_offset = 0 - 0x1000, 103 .taps = rcar_gen3_scc_taps, 104 .taps_num = ARRAY_SIZE(rcar_gen3_scc_taps), 105 /* DMAC can handle 32bit blk count but only 1 segment */ 106 .max_blk_count = UINT_MAX / TMIO_MAX_BLK_SIZE, 107 .max_segs = 1, 108 }; 109 110 static const struct renesas_sdhi_of_data of_rcar_gen3_compatible = { 111 .tmio_flags = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL | 112 TMIO_MMC_HAVE_CBSY | TMIO_MMC_MIN_RCAR2, 113 .capabilities = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ | 114 MMC_CAP_CMD23, 115 .capabilities2 = MMC_CAP2_NO_WRITE_PROTECT | MMC_CAP2_MERGE_CAPABLE, 116 .bus_shift = 2, 117 .scc_offset = 0x1000, 118 .taps = rcar_gen3_scc_taps, 119 .taps_num = ARRAY_SIZE(rcar_gen3_scc_taps), 120 /* DMAC can handle 32bit blk count but only 1 segment */ 121 .max_blk_count = UINT_MAX / TMIO_MAX_BLK_SIZE, 122 .max_segs = 1, 123 }; 124 125 static const struct of_device_id renesas_sdhi_internal_dmac_of_match[] = { 126 { .compatible = "renesas,sdhi-r7s9210", .data = &of_rza2_compatible, }, 127 { .compatible = "renesas,sdhi-mmc-r8a77470", .data = &of_rcar_gen3_compatible, }, 128 { .compatible = "renesas,sdhi-r8a7795", .data = &of_rcar_gen3_compatible, }, 129 { .compatible = "renesas,sdhi-r8a7796", .data = &of_rcar_gen3_compatible, }, 130 { .compatible = "renesas,rcar-gen3-sdhi", .data = &of_rcar_gen3_compatible, }, 131 {}, 132 }; 133 MODULE_DEVICE_TABLE(of, renesas_sdhi_internal_dmac_of_match); 134 135 static void 136 renesas_sdhi_internal_dmac_dm_write(struct tmio_mmc_host *host, 137 int addr, u64 val) 138 { 139 writeq(val, host->ctl + addr); 140 } 141 142 static void 143 renesas_sdhi_internal_dmac_enable_dma(struct tmio_mmc_host *host, bool enable) 144 { 145 struct renesas_sdhi *priv = host_to_priv(host); 146 147 if (!host->chan_tx || !host->chan_rx) 148 return; 149 150 if (!enable) 151 renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO1, 152 INFO1_CLEAR); 153 154 if (priv->dma_priv.enable) 155 priv->dma_priv.enable(host, enable); 156 } 157 158 static void 159 renesas_sdhi_internal_dmac_abort_dma(struct tmio_mmc_host *host) { 160 u64 val = RST_DTRANRST1 | RST_DTRANRST0; 161 162 renesas_sdhi_internal_dmac_enable_dma(host, false); 163 164 renesas_sdhi_internal_dmac_dm_write(host, DM_CM_RST, 165 RST_RESERVED_BITS & ~val); 166 renesas_sdhi_internal_dmac_dm_write(host, DM_CM_RST, 167 RST_RESERVED_BITS | val); 168 169 clear_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags); 170 171 renesas_sdhi_internal_dmac_enable_dma(host, true); 172 } 173 174 static void 175 renesas_sdhi_internal_dmac_dataend_dma(struct tmio_mmc_host *host) { 176 struct renesas_sdhi *priv = host_to_priv(host); 177 178 tasklet_schedule(&priv->dma_priv.dma_complete); 179 } 180 181 /* 182 * renesas_sdhi_internal_dmac_map() will be called with two difference 183 * sg pointers in two mmc_data by .pre_req(), but tmio host can have a single 184 * sg_ptr only. So, renesas_sdhi_internal_dmac_{un}map() should use a sg 185 * pointer in a mmc_data instead of host->sg_ptr. 186 */ 187 static void 188 renesas_sdhi_internal_dmac_unmap(struct tmio_mmc_host *host, 189 struct mmc_data *data, 190 enum renesas_sdhi_dma_cookie cookie) 191 { 192 bool unmap = cookie == COOKIE_UNMAPPED ? (data->host_cookie != cookie) : 193 (data->host_cookie == cookie); 194 195 if (unmap) { 196 dma_unmap_sg(&host->pdev->dev, data->sg, data->sg_len, 197 mmc_get_dma_dir(data)); 198 data->host_cookie = COOKIE_UNMAPPED; 199 } 200 } 201 202 static bool 203 renesas_sdhi_internal_dmac_map(struct tmio_mmc_host *host, 204 struct mmc_data *data, 205 enum renesas_sdhi_dma_cookie cookie) 206 { 207 if (data->host_cookie == COOKIE_PRE_MAPPED) 208 return true; 209 210 if (!dma_map_sg(&host->pdev->dev, data->sg, data->sg_len, 211 mmc_get_dma_dir(data))) 212 return false; 213 214 data->host_cookie = cookie; 215 216 /* This DMAC cannot handle if buffer is not 128-bytes alignment */ 217 if (!IS_ALIGNED(sg_dma_address(data->sg), 128)) { 218 renesas_sdhi_internal_dmac_unmap(host, data, cookie); 219 return false; 220 } 221 222 return true; 223 } 224 225 static void 226 renesas_sdhi_internal_dmac_start_dma(struct tmio_mmc_host *host, 227 struct mmc_data *data) 228 { 229 struct scatterlist *sg = host->sg_ptr; 230 u32 dtran_mode = DTRAN_MODE_BUS_WIDTH; 231 232 if (!test_bit(SDHI_INTERNAL_DMAC_ADDR_MODE_FIXED_ONLY, &global_flags)) 233 dtran_mode |= DTRAN_MODE_ADDR_MODE; 234 235 if (!renesas_sdhi_internal_dmac_map(host, data, COOKIE_MAPPED)) 236 goto force_pio; 237 238 if (data->flags & MMC_DATA_READ) { 239 dtran_mode |= DTRAN_MODE_CH_NUM_CH1; 240 if (test_bit(SDHI_INTERNAL_DMAC_ONE_RX_ONLY, &global_flags) && 241 test_and_set_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags)) 242 goto force_pio_with_unmap; 243 } else { 244 dtran_mode |= DTRAN_MODE_CH_NUM_CH0; 245 } 246 247 renesas_sdhi_internal_dmac_enable_dma(host, true); 248 249 /* set dma parameters */ 250 renesas_sdhi_internal_dmac_dm_write(host, DM_CM_DTRAN_MODE, 251 dtran_mode); 252 renesas_sdhi_internal_dmac_dm_write(host, DM_DTRAN_ADDR, 253 sg_dma_address(sg)); 254 255 host->dma_on = true; 256 257 return; 258 259 force_pio_with_unmap: 260 renesas_sdhi_internal_dmac_unmap(host, data, COOKIE_UNMAPPED); 261 262 force_pio: 263 renesas_sdhi_internal_dmac_enable_dma(host, false); 264 } 265 266 static void renesas_sdhi_internal_dmac_issue_tasklet_fn(unsigned long arg) 267 { 268 struct tmio_mmc_host *host = (struct tmio_mmc_host *)arg; 269 270 tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND); 271 272 /* start the DMAC */ 273 renesas_sdhi_internal_dmac_dm_write(host, DM_CM_DTRAN_CTRL, 274 DTRAN_CTRL_DM_START); 275 } 276 277 static bool renesas_sdhi_internal_dmac_complete(struct tmio_mmc_host *host) 278 { 279 enum dma_data_direction dir; 280 281 if (!host->dma_on) 282 return false; 283 284 if (!host->data) 285 return false; 286 287 if (host->data->flags & MMC_DATA_READ) 288 dir = DMA_FROM_DEVICE; 289 else 290 dir = DMA_TO_DEVICE; 291 292 renesas_sdhi_internal_dmac_enable_dma(host, false); 293 renesas_sdhi_internal_dmac_unmap(host, host->data, COOKIE_MAPPED); 294 295 if (dir == DMA_FROM_DEVICE) 296 clear_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags); 297 298 host->dma_on = false; 299 300 return true; 301 } 302 303 static void renesas_sdhi_internal_dmac_complete_tasklet_fn(unsigned long arg) 304 { 305 struct tmio_mmc_host *host = (struct tmio_mmc_host *)arg; 306 307 spin_lock_irq(&host->lock); 308 if (!renesas_sdhi_internal_dmac_complete(host)) 309 goto out; 310 311 tmio_mmc_do_data_irq(host); 312 out: 313 spin_unlock_irq(&host->lock); 314 } 315 316 static void renesas_sdhi_internal_dmac_end_dma(struct tmio_mmc_host *host) 317 { 318 if (host->data) 319 renesas_sdhi_internal_dmac_complete(host); 320 } 321 322 static void renesas_sdhi_internal_dmac_post_req(struct mmc_host *mmc, 323 struct mmc_request *mrq, 324 int err) 325 { 326 struct tmio_mmc_host *host = mmc_priv(mmc); 327 struct mmc_data *data = mrq->data; 328 329 if (!data) 330 return; 331 332 renesas_sdhi_internal_dmac_unmap(host, data, COOKIE_UNMAPPED); 333 } 334 335 static void renesas_sdhi_internal_dmac_pre_req(struct mmc_host *mmc, 336 struct mmc_request *mrq) 337 { 338 struct tmio_mmc_host *host = mmc_priv(mmc); 339 struct mmc_data *data = mrq->data; 340 341 if (!data) 342 return; 343 344 data->host_cookie = COOKIE_UNMAPPED; 345 renesas_sdhi_internal_dmac_map(host, data, COOKIE_PRE_MAPPED); 346 } 347 348 static void 349 renesas_sdhi_internal_dmac_request_dma(struct tmio_mmc_host *host, 350 struct tmio_mmc_data *pdata) 351 { 352 struct renesas_sdhi *priv = host_to_priv(host); 353 354 /* Disable DMAC interrupts, we don't use them */ 355 renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO1_MASK, 356 INFO1_MASK_CLEAR); 357 renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO2_MASK, 358 INFO2_MASK_CLEAR); 359 360 /* Each value is set to non-zero to assume "enabling" each DMA */ 361 host->chan_rx = host->chan_tx = (void *)0xdeadbeaf; 362 363 tasklet_init(&priv->dma_priv.dma_complete, 364 renesas_sdhi_internal_dmac_complete_tasklet_fn, 365 (unsigned long)host); 366 tasklet_init(&host->dma_issue, 367 renesas_sdhi_internal_dmac_issue_tasklet_fn, 368 (unsigned long)host); 369 370 /* Add pre_req and post_req */ 371 host->ops.pre_req = renesas_sdhi_internal_dmac_pre_req; 372 host->ops.post_req = renesas_sdhi_internal_dmac_post_req; 373 } 374 375 static void 376 renesas_sdhi_internal_dmac_release_dma(struct tmio_mmc_host *host) 377 { 378 /* Each value is set to zero to assume "disabling" each DMA */ 379 host->chan_rx = host->chan_tx = NULL; 380 } 381 382 static const struct tmio_mmc_dma_ops renesas_sdhi_internal_dmac_dma_ops = { 383 .start = renesas_sdhi_internal_dmac_start_dma, 384 .enable = renesas_sdhi_internal_dmac_enable_dma, 385 .request = renesas_sdhi_internal_dmac_request_dma, 386 .release = renesas_sdhi_internal_dmac_release_dma, 387 .abort = renesas_sdhi_internal_dmac_abort_dma, 388 .dataend = renesas_sdhi_internal_dmac_dataend_dma, 389 .end = renesas_sdhi_internal_dmac_end_dma, 390 }; 391 392 /* 393 * Whitelist of specific R-Car Gen3 SoC ES versions to use this DMAC 394 * implementation as others may use a different implementation. 395 */ 396 static const struct soc_device_attribute soc_dma_quirks[] = { 397 { .soc_id = "r7s9210", 398 .data = (void *)BIT(SDHI_INTERNAL_DMAC_ADDR_MODE_FIXED_ONLY) }, 399 { .soc_id = "r8a7795", .revision = "ES1.*", 400 .data = (void *)BIT(SDHI_INTERNAL_DMAC_ONE_RX_ONLY) }, 401 { .soc_id = "r8a7796", .revision = "ES1.0", 402 .data = (void *)BIT(SDHI_INTERNAL_DMAC_ONE_RX_ONLY) }, 403 { /* sentinel */ } 404 }; 405 406 static int renesas_sdhi_internal_dmac_probe(struct platform_device *pdev) 407 { 408 const struct soc_device_attribute *soc = soc_device_match(soc_dma_quirks); 409 struct device *dev = &pdev->dev; 410 411 if (soc) 412 global_flags |= (unsigned long)soc->data; 413 414 /* value is max of SD_SECCNT. Confirmed by HW engineers */ 415 dma_set_max_seg_size(dev, 0xffffffff); 416 417 return renesas_sdhi_probe(pdev, &renesas_sdhi_internal_dmac_dma_ops); 418 } 419 420 static const struct dev_pm_ops renesas_sdhi_internal_dmac_dev_pm_ops = { 421 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, 422 pm_runtime_force_resume) 423 SET_RUNTIME_PM_OPS(tmio_mmc_host_runtime_suspend, 424 tmio_mmc_host_runtime_resume, 425 NULL) 426 }; 427 428 static struct platform_driver renesas_internal_dmac_sdhi_driver = { 429 .driver = { 430 .name = "renesas_sdhi_internal_dmac", 431 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 432 .pm = &renesas_sdhi_internal_dmac_dev_pm_ops, 433 .of_match_table = renesas_sdhi_internal_dmac_of_match, 434 }, 435 .probe = renesas_sdhi_internal_dmac_probe, 436 .remove = renesas_sdhi_remove, 437 }; 438 439 module_platform_driver(renesas_internal_dmac_sdhi_driver); 440 441 MODULE_DESCRIPTION("Renesas SDHI driver for internal DMAC"); 442 MODULE_AUTHOR("Yoshihiro Shimoda"); 443 MODULE_LICENSE("GPL v2"); 444