1 /* 2 * EIM driver for Freescale's i.MX chips 3 * 4 * Copyright (C) 2013 Freescale Semiconductor, Inc. 5 * 6 * This file is licensed under the terms of the GNU General Public 7 * License version 2. This program is licensed "as is" without any 8 * warranty of any kind, whether express or implied. 9 */ 10 #include <linux/module.h> 11 #include <linux/clk.h> 12 #include <linux/io.h> 13 #include <linux/of_address.h> 14 #include <linux/of_device.h> 15 #include <linux/mfd/syscon.h> 16 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h> 17 #include <linux/regmap.h> 18 19 struct imx_weim_devtype { 20 unsigned int cs_count; 21 unsigned int cs_regs_count; 22 unsigned int cs_stride; 23 unsigned int wcr_offset; 24 unsigned int wcr_bcm; 25 unsigned int wcr_cont_bclk; 26 }; 27 28 static const struct imx_weim_devtype imx1_weim_devtype = { 29 .cs_count = 6, 30 .cs_regs_count = 2, 31 .cs_stride = 0x08, 32 }; 33 34 static const struct imx_weim_devtype imx27_weim_devtype = { 35 .cs_count = 6, 36 .cs_regs_count = 3, 37 .cs_stride = 0x10, 38 }; 39 40 static const struct imx_weim_devtype imx50_weim_devtype = { 41 .cs_count = 4, 42 .cs_regs_count = 6, 43 .cs_stride = 0x18, 44 .wcr_offset = 0x90, 45 .wcr_bcm = BIT(0), 46 .wcr_cont_bclk = BIT(3), 47 }; 48 49 static const struct imx_weim_devtype imx51_weim_devtype = { 50 .cs_count = 6, 51 .cs_regs_count = 6, 52 .cs_stride = 0x18, 53 }; 54 55 #define MAX_CS_REGS_COUNT 6 56 #define MAX_CS_COUNT 6 57 #define OF_REG_SIZE 3 58 59 struct cs_timing { 60 bool is_applied; 61 u32 regs[MAX_CS_REGS_COUNT]; 62 }; 63 64 struct cs_timing_state { 65 struct cs_timing cs[MAX_CS_COUNT]; 66 }; 67 68 struct weim_priv { 69 void __iomem *base; 70 struct cs_timing_state timing_state; 71 }; 72 73 static const struct of_device_id weim_id_table[] = { 74 /* i.MX1/21 */ 75 { .compatible = "fsl,imx1-weim", .data = &imx1_weim_devtype, }, 76 /* i.MX25/27/31/35 */ 77 { .compatible = "fsl,imx27-weim", .data = &imx27_weim_devtype, }, 78 /* i.MX50/53/6Q */ 79 { .compatible = "fsl,imx50-weim", .data = &imx50_weim_devtype, }, 80 { .compatible = "fsl,imx6q-weim", .data = &imx50_weim_devtype, }, 81 /* i.MX51 */ 82 { .compatible = "fsl,imx51-weim", .data = &imx51_weim_devtype, }, 83 { } 84 }; 85 MODULE_DEVICE_TABLE(of, weim_id_table); 86 87 static int imx_weim_gpr_setup(struct platform_device *pdev) 88 { 89 struct device_node *np = pdev->dev.of_node; 90 struct of_range_parser parser; 91 struct of_range range; 92 struct regmap *gpr; 93 u32 gprvals[4] = { 94 05, /* CS0(128M) CS1(0M) CS2(0M) CS3(0M) */ 95 033, /* CS0(64M) CS1(64M) CS2(0M) CS3(0M) */ 96 0113, /* CS0(64M) CS1(32M) CS2(32M) CS3(0M) */ 97 01111, /* CS0(32M) CS1(32M) CS2(32M) CS3(32M) */ 98 }; 99 u32 gprval = 0; 100 u32 val; 101 int cs = 0; 102 int i = 0; 103 104 gpr = syscon_regmap_lookup_by_phandle(np, "fsl,weim-cs-gpr"); 105 if (IS_ERR(gpr)) { 106 dev_dbg(&pdev->dev, "failed to find weim-cs-gpr\n"); 107 return 0; 108 } 109 110 if (of_range_parser_init(&parser, np)) 111 goto err; 112 113 for_each_of_range(&parser, &range) { 114 cs = range.bus_addr >> 32; 115 val = (range.size / SZ_32M) | 1; 116 gprval |= val << cs * 3; 117 i++; 118 } 119 120 if (i == 0 || i % 4) 121 goto err; 122 123 for (i = 0; i < ARRAY_SIZE(gprvals); i++) { 124 if (gprval == gprvals[i]) { 125 /* Found it. Set up IOMUXC_GPR1[11:0] with it. */ 126 regmap_update_bits(gpr, IOMUXC_GPR1, 0xfff, gprval); 127 return 0; 128 } 129 } 130 131 err: 132 dev_err(&pdev->dev, "Invalid 'ranges' configuration\n"); 133 return -EINVAL; 134 } 135 136 /* Parse and set the timing for this device. */ 137 static int weim_timing_setup(struct device *dev, struct device_node *np, 138 const struct imx_weim_devtype *devtype) 139 { 140 u32 cs_idx, value[MAX_CS_REGS_COUNT]; 141 int i, ret; 142 int reg_idx, num_regs; 143 struct cs_timing *cst; 144 struct weim_priv *priv; 145 struct cs_timing_state *ts; 146 void __iomem *base; 147 148 if (WARN_ON(devtype->cs_regs_count > MAX_CS_REGS_COUNT)) 149 return -EINVAL; 150 if (WARN_ON(devtype->cs_count > MAX_CS_COUNT)) 151 return -EINVAL; 152 153 priv = dev_get_drvdata(dev); 154 base = priv->base; 155 ts = &priv->timing_state; 156 157 ret = of_property_read_u32_array(np, "fsl,weim-cs-timing", 158 value, devtype->cs_regs_count); 159 if (ret) 160 return ret; 161 162 /* 163 * the child node's "reg" property may contain multiple address ranges, 164 * extract the chip select for each. 165 */ 166 num_regs = of_property_count_elems_of_size(np, "reg", OF_REG_SIZE); 167 if (num_regs < 0) 168 return num_regs; 169 if (!num_regs) 170 return -EINVAL; 171 for (reg_idx = 0; reg_idx < num_regs; reg_idx++) { 172 /* get the CS index from this child node's "reg" property. */ 173 ret = of_property_read_u32_index(np, "reg", 174 reg_idx * OF_REG_SIZE, &cs_idx); 175 if (ret) 176 break; 177 178 if (cs_idx >= devtype->cs_count) 179 return -EINVAL; 180 181 /* prevent re-configuring a CS that's already been configured */ 182 cst = &ts->cs[cs_idx]; 183 if (cst->is_applied && memcmp(value, cst->regs, 184 devtype->cs_regs_count * sizeof(u32))) { 185 dev_err(dev, "fsl,weim-cs-timing conflict on %pOF", np); 186 return -EINVAL; 187 } 188 189 /* set the timing for WEIM */ 190 for (i = 0; i < devtype->cs_regs_count; i++) 191 writel(value[i], 192 base + cs_idx * devtype->cs_stride + i * 4); 193 if (!cst->is_applied) { 194 cst->is_applied = true; 195 memcpy(cst->regs, value, 196 devtype->cs_regs_count * sizeof(u32)); 197 } 198 } 199 200 return 0; 201 } 202 203 static int weim_parse_dt(struct platform_device *pdev) 204 { 205 const struct of_device_id *of_id = of_match_device(weim_id_table, 206 &pdev->dev); 207 const struct imx_weim_devtype *devtype = of_id->data; 208 int ret = 0, have_child = 0; 209 struct device_node *child; 210 struct weim_priv *priv; 211 void __iomem *base; 212 u32 reg; 213 214 if (devtype == &imx50_weim_devtype) { 215 ret = imx_weim_gpr_setup(pdev); 216 if (ret) 217 return ret; 218 } 219 220 priv = dev_get_drvdata(&pdev->dev); 221 base = priv->base; 222 223 if (of_property_read_bool(pdev->dev.of_node, "fsl,burst-clk-enable")) { 224 if (devtype->wcr_bcm) { 225 reg = readl(base + devtype->wcr_offset); 226 reg |= devtype->wcr_bcm; 227 228 if (of_property_read_bool(pdev->dev.of_node, 229 "fsl,continuous-burst-clk")) { 230 if (devtype->wcr_cont_bclk) { 231 reg |= devtype->wcr_cont_bclk; 232 } else { 233 dev_err(&pdev->dev, 234 "continuous burst clk not supported.\n"); 235 return -EINVAL; 236 } 237 } 238 239 writel(reg, base + devtype->wcr_offset); 240 } else { 241 dev_err(&pdev->dev, "burst clk mode not supported.\n"); 242 return -EINVAL; 243 } 244 } 245 246 for_each_available_child_of_node(pdev->dev.of_node, child) { 247 ret = weim_timing_setup(&pdev->dev, child, devtype); 248 if (ret) 249 dev_warn(&pdev->dev, "%pOF set timing failed.\n", 250 child); 251 else 252 have_child = 1; 253 } 254 255 if (have_child) 256 ret = of_platform_default_populate(pdev->dev.of_node, 257 NULL, &pdev->dev); 258 if (ret) 259 dev_err(&pdev->dev, "%pOF fail to create devices.\n", 260 pdev->dev.of_node); 261 return ret; 262 } 263 264 static int weim_probe(struct platform_device *pdev) 265 { 266 struct weim_priv *priv; 267 struct clk *clk; 268 void __iomem *base; 269 int ret; 270 271 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); 272 if (!priv) 273 return -ENOMEM; 274 275 /* get the resource */ 276 base = devm_platform_ioremap_resource(pdev, 0); 277 if (IS_ERR(base)) 278 return PTR_ERR(base); 279 280 priv->base = base; 281 dev_set_drvdata(&pdev->dev, priv); 282 283 /* get the clock */ 284 clk = devm_clk_get(&pdev->dev, NULL); 285 if (IS_ERR(clk)) 286 return PTR_ERR(clk); 287 288 ret = clk_prepare_enable(clk); 289 if (ret) 290 return ret; 291 292 /* parse the device node */ 293 ret = weim_parse_dt(pdev); 294 if (ret) 295 clk_disable_unprepare(clk); 296 else 297 dev_info(&pdev->dev, "Driver registered.\n"); 298 299 return ret; 300 } 301 302 #if IS_ENABLED(CONFIG_OF_DYNAMIC) 303 static int of_weim_notify(struct notifier_block *nb, unsigned long action, 304 void *arg) 305 { 306 const struct imx_weim_devtype *devtype; 307 struct of_reconfig_data *rd = arg; 308 const struct of_device_id *of_id; 309 struct platform_device *pdev; 310 int ret = NOTIFY_OK; 311 312 switch (of_reconfig_get_state_change(action, rd)) { 313 case OF_RECONFIG_CHANGE_ADD: 314 of_id = of_match_node(weim_id_table, rd->dn->parent); 315 if (!of_id) 316 return NOTIFY_OK; /* not for us */ 317 318 devtype = of_id->data; 319 320 pdev = of_find_device_by_node(rd->dn->parent); 321 if (!pdev) { 322 pr_err("%s: could not find platform device for '%pOF'\n", 323 __func__, rd->dn->parent); 324 325 return notifier_from_errno(-EINVAL); 326 } 327 328 if (weim_timing_setup(&pdev->dev, rd->dn, devtype)) 329 dev_warn(&pdev->dev, 330 "Failed to setup timing for '%pOF'\n", rd->dn); 331 332 if (!of_node_check_flag(rd->dn, OF_POPULATED)) { 333 /* 334 * Clear the flag before adding the device so that 335 * fw_devlink doesn't skip adding consumers to this 336 * device. 337 */ 338 rd->dn->fwnode.flags &= ~FWNODE_FLAG_NOT_DEVICE; 339 if (!of_platform_device_create(rd->dn, NULL, &pdev->dev)) { 340 dev_err(&pdev->dev, 341 "Failed to create child device '%pOF'\n", 342 rd->dn); 343 ret = notifier_from_errno(-EINVAL); 344 } 345 } 346 347 platform_device_put(pdev); 348 349 break; 350 case OF_RECONFIG_CHANGE_REMOVE: 351 if (!of_node_check_flag(rd->dn, OF_POPULATED)) 352 return NOTIFY_OK; /* device already destroyed */ 353 354 of_id = of_match_node(weim_id_table, rd->dn->parent); 355 if (!of_id) 356 return NOTIFY_OK; /* not for us */ 357 358 pdev = of_find_device_by_node(rd->dn); 359 if (!pdev) { 360 pr_err("Could not find platform device for '%pOF'\n", 361 rd->dn); 362 363 ret = notifier_from_errno(-EINVAL); 364 } else { 365 of_platform_device_destroy(&pdev->dev, NULL); 366 platform_device_put(pdev); 367 } 368 369 break; 370 default: 371 break; 372 } 373 374 return ret; 375 } 376 377 static struct notifier_block weim_of_notifier = { 378 .notifier_call = of_weim_notify, 379 }; 380 #endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ 381 382 static struct platform_driver weim_driver = { 383 .driver = { 384 .name = "imx-weim", 385 .of_match_table = weim_id_table, 386 }, 387 .probe = weim_probe, 388 }; 389 390 static int __init weim_init(void) 391 { 392 #if IS_ENABLED(CONFIG_OF_DYNAMIC) 393 WARN_ON(of_reconfig_notifier_register(&weim_of_notifier)); 394 #endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ 395 396 return platform_driver_register(&weim_driver); 397 } 398 module_init(weim_init); 399 400 static void __exit weim_exit(void) 401 { 402 #if IS_ENABLED(CONFIG_OF_DYNAMIC) 403 of_reconfig_notifier_unregister(&weim_of_notifier); 404 #endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ 405 406 return platform_driver_unregister(&weim_driver); 407 408 } 409 module_exit(weim_exit); 410 411 MODULE_AUTHOR("Freescale Semiconductor Inc."); 412 MODULE_DESCRIPTION("i.MX EIM Controller Driver"); 413 MODULE_LICENSE("GPL"); 414