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 /* 60 * Specification of this driver: 61 * - host->chan_{rx,tx} will be used as a flag of enabling/disabling the dma 62 * - Since this SDHI DMAC register set has 16 but 32-bit width, we 63 * need a custom accessor. 64 */ 65 66 static unsigned long global_flags; 67 /* 68 * Workaround for avoiding to use RX DMAC by multiple channels. 69 * On R-Car H3 ES1.* and M3-W ES1.0, when multiple SDHI channels use 70 * RX DMAC simultaneously, sometimes hundreds of bytes data are not 71 * stored into the system memory even if the DMAC interrupt happened. 72 * So, this driver then uses one RX DMAC channel only. 73 */ 74 #define SDHI_INTERNAL_DMAC_ONE_RX_ONLY 0 75 #define SDHI_INTERNAL_DMAC_RX_IN_USE 1 76 77 /* RZ/A2 does not have the ADRR_MODE bit */ 78 #define SDHI_INTERNAL_DMAC_ADDR_MODE_FIXED_ONLY 2 79 80 /* Definitions for sampling clocks */ 81 static struct renesas_sdhi_scc rcar_gen3_scc_taps[] = { 82 { 83 .clk_rate = 0, 84 .tap = 0x00000300, 85 .tap_hs400_4tap = 0x00000100, 86 }, 87 }; 88 89 static const struct renesas_sdhi_of_data of_rza2_compatible = { 90 .tmio_flags = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL | 91 TMIO_MMC_HAVE_CBSY, 92 .tmio_ocr_mask = MMC_VDD_32_33, 93 .capabilities = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ | 94 MMC_CAP_CMD23, 95 .bus_shift = 2, 96 .scc_offset = 0 - 0x1000, 97 .taps = rcar_gen3_scc_taps, 98 .taps_num = ARRAY_SIZE(rcar_gen3_scc_taps), 99 /* DMAC can handle 32bit blk count but only 1 segment */ 100 .max_blk_count = UINT_MAX / TMIO_MAX_BLK_SIZE, 101 .max_segs = 1, 102 }; 103 104 static const struct renesas_sdhi_of_data of_rcar_gen3_compatible = { 105 .tmio_flags = TMIO_MMC_HAS_IDLE_WAIT | TMIO_MMC_CLK_ACTUAL | 106 TMIO_MMC_HAVE_CBSY | TMIO_MMC_MIN_RCAR2, 107 .capabilities = MMC_CAP_SD_HIGHSPEED | MMC_CAP_SDIO_IRQ | 108 MMC_CAP_CMD23, 109 .capabilities2 = MMC_CAP2_NO_WRITE_PROTECT | MMC_CAP2_MERGE_CAPABLE, 110 .bus_shift = 2, 111 .scc_offset = 0x1000, 112 .taps = rcar_gen3_scc_taps, 113 .taps_num = ARRAY_SIZE(rcar_gen3_scc_taps), 114 /* DMAC can handle 32bit blk count but only 1 segment */ 115 .max_blk_count = UINT_MAX / TMIO_MAX_BLK_SIZE, 116 .max_segs = 1, 117 }; 118 119 static const struct of_device_id renesas_sdhi_internal_dmac_of_match[] = { 120 { .compatible = "renesas,sdhi-r7s9210", .data = &of_rza2_compatible, }, 121 { .compatible = "renesas,sdhi-mmc-r8a77470", .data = &of_rcar_gen3_compatible, }, 122 { .compatible = "renesas,sdhi-r8a7795", .data = &of_rcar_gen3_compatible, }, 123 { .compatible = "renesas,sdhi-r8a7796", .data = &of_rcar_gen3_compatible, }, 124 { .compatible = "renesas,rcar-gen3-sdhi", .data = &of_rcar_gen3_compatible, }, 125 {}, 126 }; 127 MODULE_DEVICE_TABLE(of, renesas_sdhi_internal_dmac_of_match); 128 129 static void 130 renesas_sdhi_internal_dmac_dm_write(struct tmio_mmc_host *host, 131 int addr, u64 val) 132 { 133 writeq(val, host->ctl + addr); 134 } 135 136 static void 137 renesas_sdhi_internal_dmac_enable_dma(struct tmio_mmc_host *host, bool enable) 138 { 139 struct renesas_sdhi *priv = host_to_priv(host); 140 141 if (!host->chan_tx || !host->chan_rx) 142 return; 143 144 if (!enable) 145 renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO1, 146 INFO1_CLEAR); 147 148 if (priv->dma_priv.enable) 149 priv->dma_priv.enable(host, enable); 150 } 151 152 static void 153 renesas_sdhi_internal_dmac_abort_dma(struct tmio_mmc_host *host) { 154 u64 val = RST_DTRANRST1 | RST_DTRANRST0; 155 156 renesas_sdhi_internal_dmac_enable_dma(host, false); 157 158 renesas_sdhi_internal_dmac_dm_write(host, DM_CM_RST, 159 RST_RESERVED_BITS & ~val); 160 renesas_sdhi_internal_dmac_dm_write(host, DM_CM_RST, 161 RST_RESERVED_BITS | val); 162 163 clear_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags); 164 165 renesas_sdhi_internal_dmac_enable_dma(host, true); 166 } 167 168 static void 169 renesas_sdhi_internal_dmac_dataend_dma(struct tmio_mmc_host *host) { 170 struct renesas_sdhi *priv = host_to_priv(host); 171 172 tasklet_schedule(&priv->dma_priv.dma_complete); 173 } 174 175 static void 176 renesas_sdhi_internal_dmac_start_dma(struct tmio_mmc_host *host, 177 struct mmc_data *data) 178 { 179 struct scatterlist *sg = host->sg_ptr; 180 u32 dtran_mode = DTRAN_MODE_BUS_WIDTH; 181 182 if (!test_bit(SDHI_INTERNAL_DMAC_ADDR_MODE_FIXED_ONLY, &global_flags)) 183 dtran_mode |= DTRAN_MODE_ADDR_MODE; 184 185 if (!dma_map_sg(&host->pdev->dev, sg, host->sg_len, 186 mmc_get_dma_dir(data))) 187 goto force_pio; 188 189 /* This DMAC cannot handle if buffer is not 8-bytes alignment */ 190 if (!IS_ALIGNED(sg_dma_address(sg), 8)) 191 goto force_pio_with_unmap; 192 193 if (data->flags & MMC_DATA_READ) { 194 dtran_mode |= DTRAN_MODE_CH_NUM_CH1; 195 if (test_bit(SDHI_INTERNAL_DMAC_ONE_RX_ONLY, &global_flags) && 196 test_and_set_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags)) 197 goto force_pio_with_unmap; 198 } else { 199 dtran_mode |= DTRAN_MODE_CH_NUM_CH0; 200 } 201 202 renesas_sdhi_internal_dmac_enable_dma(host, true); 203 204 /* set dma parameters */ 205 renesas_sdhi_internal_dmac_dm_write(host, DM_CM_DTRAN_MODE, 206 dtran_mode); 207 renesas_sdhi_internal_dmac_dm_write(host, DM_DTRAN_ADDR, 208 sg_dma_address(sg)); 209 210 host->dma_on = true; 211 212 return; 213 214 force_pio_with_unmap: 215 dma_unmap_sg(&host->pdev->dev, sg, host->sg_len, mmc_get_dma_dir(data)); 216 217 force_pio: 218 renesas_sdhi_internal_dmac_enable_dma(host, false); 219 } 220 221 static void renesas_sdhi_internal_dmac_issue_tasklet_fn(unsigned long arg) 222 { 223 struct tmio_mmc_host *host = (struct tmio_mmc_host *)arg; 224 225 tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND); 226 227 /* start the DMAC */ 228 renesas_sdhi_internal_dmac_dm_write(host, DM_CM_DTRAN_CTRL, 229 DTRAN_CTRL_DM_START); 230 } 231 232 static void renesas_sdhi_internal_dmac_complete_tasklet_fn(unsigned long arg) 233 { 234 struct tmio_mmc_host *host = (struct tmio_mmc_host *)arg; 235 enum dma_data_direction dir; 236 237 spin_lock_irq(&host->lock); 238 239 if (!host->data) 240 goto out; 241 242 if (host->data->flags & MMC_DATA_READ) 243 dir = DMA_FROM_DEVICE; 244 else 245 dir = DMA_TO_DEVICE; 246 247 renesas_sdhi_internal_dmac_enable_dma(host, false); 248 dma_unmap_sg(&host->pdev->dev, host->sg_ptr, host->sg_len, dir); 249 250 if (dir == DMA_FROM_DEVICE) 251 clear_bit(SDHI_INTERNAL_DMAC_RX_IN_USE, &global_flags); 252 253 tmio_mmc_do_data_irq(host); 254 out: 255 spin_unlock_irq(&host->lock); 256 } 257 258 static void 259 renesas_sdhi_internal_dmac_request_dma(struct tmio_mmc_host *host, 260 struct tmio_mmc_data *pdata) 261 { 262 struct renesas_sdhi *priv = host_to_priv(host); 263 264 /* Disable DMAC interrupts, we don't use them */ 265 renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO1_MASK, 266 INFO1_MASK_CLEAR); 267 renesas_sdhi_internal_dmac_dm_write(host, DM_CM_INFO2_MASK, 268 INFO2_MASK_CLEAR); 269 270 /* Each value is set to non-zero to assume "enabling" each DMA */ 271 host->chan_rx = host->chan_tx = (void *)0xdeadbeaf; 272 273 tasklet_init(&priv->dma_priv.dma_complete, 274 renesas_sdhi_internal_dmac_complete_tasklet_fn, 275 (unsigned long)host); 276 tasklet_init(&host->dma_issue, 277 renesas_sdhi_internal_dmac_issue_tasklet_fn, 278 (unsigned long)host); 279 } 280 281 static void 282 renesas_sdhi_internal_dmac_release_dma(struct tmio_mmc_host *host) 283 { 284 /* Each value is set to zero to assume "disabling" each DMA */ 285 host->chan_rx = host->chan_tx = NULL; 286 } 287 288 static const struct tmio_mmc_dma_ops renesas_sdhi_internal_dmac_dma_ops = { 289 .start = renesas_sdhi_internal_dmac_start_dma, 290 .enable = renesas_sdhi_internal_dmac_enable_dma, 291 .request = renesas_sdhi_internal_dmac_request_dma, 292 .release = renesas_sdhi_internal_dmac_release_dma, 293 .abort = renesas_sdhi_internal_dmac_abort_dma, 294 .dataend = renesas_sdhi_internal_dmac_dataend_dma, 295 }; 296 297 /* 298 * Whitelist of specific R-Car Gen3 SoC ES versions to use this DMAC 299 * implementation as others may use a different implementation. 300 */ 301 static const struct soc_device_attribute soc_dma_quirks[] = { 302 { .soc_id = "r7s9210", 303 .data = (void *)BIT(SDHI_INTERNAL_DMAC_ADDR_MODE_FIXED_ONLY) }, 304 { .soc_id = "r8a7795", .revision = "ES1.*", 305 .data = (void *)BIT(SDHI_INTERNAL_DMAC_ONE_RX_ONLY) }, 306 { .soc_id = "r8a7796", .revision = "ES1.0", 307 .data = (void *)BIT(SDHI_INTERNAL_DMAC_ONE_RX_ONLY) }, 308 { /* sentinel */ } 309 }; 310 311 static int renesas_sdhi_internal_dmac_probe(struct platform_device *pdev) 312 { 313 const struct soc_device_attribute *soc = soc_device_match(soc_dma_quirks); 314 struct device *dev = &pdev->dev; 315 316 if (soc) 317 global_flags |= (unsigned long)soc->data; 318 319 dev->dma_parms = devm_kzalloc(dev, sizeof(*dev->dma_parms), GFP_KERNEL); 320 if (!dev->dma_parms) 321 return -ENOMEM; 322 323 /* value is max of SD_SECCNT. Confirmed by HW engineers */ 324 dma_set_max_seg_size(dev, 0xffffffff); 325 326 return renesas_sdhi_probe(pdev, &renesas_sdhi_internal_dmac_dma_ops); 327 } 328 329 static const struct dev_pm_ops renesas_sdhi_internal_dmac_dev_pm_ops = { 330 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, 331 pm_runtime_force_resume) 332 SET_RUNTIME_PM_OPS(tmio_mmc_host_runtime_suspend, 333 tmio_mmc_host_runtime_resume, 334 NULL) 335 }; 336 337 static struct platform_driver renesas_internal_dmac_sdhi_driver = { 338 .driver = { 339 .name = "renesas_sdhi_internal_dmac", 340 .pm = &renesas_sdhi_internal_dmac_dev_pm_ops, 341 .of_match_table = renesas_sdhi_internal_dmac_of_match, 342 }, 343 .probe = renesas_sdhi_internal_dmac_probe, 344 .remove = renesas_sdhi_remove, 345 }; 346 347 module_platform_driver(renesas_internal_dmac_sdhi_driver); 348 349 MODULE_DESCRIPTION("Renesas SDHI driver for internal DMAC"); 350 MODULE_AUTHOR("Yoshihiro Shimoda"); 351 MODULE_LICENSE("GPL v2"); 352