1 /* 2 * Copyright 2024 NXP 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 #include <errno.h> 7 8 #include <s32cc-clk-regs.h> 9 10 #include <common/debug.h> 11 #include <drivers/clk.h> 12 #include <lib/mmio.h> 13 #include <s32cc-clk-modules.h> 14 #include <s32cc-clk-utils.h> 15 16 #define MAX_STACK_DEPTH (15U) 17 18 struct s32cc_clk_drv { 19 uintptr_t fxosc_base; 20 }; 21 22 static int update_stack_depth(unsigned int *depth) 23 { 24 if (*depth == 0U) { 25 return -ENOMEM; 26 } 27 28 (*depth)--; 29 return 0; 30 } 31 32 static struct s32cc_clk_drv *get_drv(void) 33 { 34 static struct s32cc_clk_drv driver = { 35 .fxosc_base = FXOSC_BASE_ADDR, 36 }; 37 38 return &driver; 39 } 40 41 static int enable_module(const struct s32cc_clk_obj *module, unsigned int *depth); 42 43 static int enable_clk_module(const struct s32cc_clk_obj *module, 44 const struct s32cc_clk_drv *drv, 45 unsigned int *depth) 46 { 47 const struct s32cc_clk *clk = s32cc_obj2clk(module); 48 int ret; 49 50 ret = update_stack_depth(depth); 51 if (ret != 0) { 52 return ret; 53 } 54 55 if (clk == NULL) { 56 return -EINVAL; 57 } 58 59 if (clk->module != NULL) { 60 return enable_module(clk->module, depth); 61 } 62 63 if (clk->pclock != NULL) { 64 return enable_clk_module(&clk->pclock->desc, drv, depth); 65 } 66 67 return -EINVAL; 68 } 69 70 static void enable_fxosc(const struct s32cc_clk_drv *drv) 71 { 72 uintptr_t fxosc_base = drv->fxosc_base; 73 uint32_t ctrl; 74 75 ctrl = mmio_read_32(FXOSC_CTRL(fxosc_base)); 76 if ((ctrl & FXOSC_CTRL_OSCON) != U(0)) { 77 return; 78 } 79 80 ctrl = FXOSC_CTRL_COMP_EN; 81 ctrl &= ~FXOSC_CTRL_OSC_BYP; 82 ctrl |= FXOSC_CTRL_EOCV(0x1); 83 ctrl |= FXOSC_CTRL_GM_SEL(0x7); 84 mmio_write_32(FXOSC_CTRL(fxosc_base), ctrl); 85 86 /* Switch ON the crystal oscillator. */ 87 mmio_setbits_32(FXOSC_CTRL(fxosc_base), FXOSC_CTRL_OSCON); 88 89 /* Wait until the clock is stable. */ 90 while ((mmio_read_32(FXOSC_STAT(fxosc_base)) & FXOSC_STAT_OSC_STAT) == U(0)) { 91 } 92 } 93 94 static int enable_osc(const struct s32cc_clk_obj *module, 95 const struct s32cc_clk_drv *drv, 96 unsigned int *depth) 97 { 98 const struct s32cc_osc *osc = s32cc_obj2osc(module); 99 int ret = 0; 100 101 ret = update_stack_depth(depth); 102 if (ret != 0) { 103 return ret; 104 } 105 106 switch (osc->source) { 107 case S32CC_FXOSC: 108 enable_fxosc(drv); 109 break; 110 /* FIRC and SIRC oscillators are enabled by default */ 111 case S32CC_FIRC: 112 break; 113 case S32CC_SIRC: 114 break; 115 default: 116 ERROR("Invalid oscillator %d\n", osc->source); 117 ret = -EINVAL; 118 break; 119 }; 120 121 return ret; 122 } 123 124 static int enable_module(const struct s32cc_clk_obj *module, unsigned int *depth) 125 { 126 const struct s32cc_clk_drv *drv = get_drv(); 127 int ret = 0; 128 129 ret = update_stack_depth(depth); 130 if (ret != 0) { 131 return ret; 132 } 133 134 if (drv == NULL) { 135 return -EINVAL; 136 } 137 138 switch (module->type) { 139 case s32cc_osc_t: 140 ret = enable_osc(module, drv, depth); 141 break; 142 case s32cc_clk_t: 143 ret = enable_clk_module(module, drv, depth); 144 break; 145 case s32cc_clkmux_t: 146 ret = -ENOTSUP; 147 break; 148 case s32cc_shared_clkmux_t: 149 ret = -ENOTSUP; 150 break; 151 case s32cc_pll_t: 152 ret = -ENOTSUP; 153 break; 154 case s32cc_pll_out_div_t: 155 case s32cc_fixed_div_t: 156 ret = -ENOTSUP; 157 break; 158 default: 159 ret = -EINVAL; 160 break; 161 } 162 163 return ret; 164 } 165 166 static int s32cc_clk_enable(unsigned long id) 167 { 168 unsigned int depth = MAX_STACK_DEPTH; 169 const struct s32cc_clk *clk; 170 171 clk = s32cc_get_arch_clk(id); 172 if (clk == NULL) { 173 return -EINVAL; 174 } 175 176 return enable_module(&clk->desc, &depth); 177 } 178 179 static void s32cc_clk_disable(unsigned long id) 180 { 181 } 182 183 static bool s32cc_clk_is_enabled(unsigned long id) 184 { 185 return false; 186 } 187 188 static unsigned long s32cc_clk_get_rate(unsigned long id) 189 { 190 return 0; 191 } 192 193 static int set_module_rate(const struct s32cc_clk_obj *module, 194 unsigned long rate, unsigned long *orate, 195 unsigned int *depth); 196 197 static int set_osc_freq(const struct s32cc_clk_obj *module, unsigned long rate, 198 unsigned long *orate, unsigned int *depth) 199 { 200 struct s32cc_osc *osc = s32cc_obj2osc(module); 201 int ret; 202 203 ret = update_stack_depth(depth); 204 if (ret != 0) { 205 return ret; 206 } 207 208 if ((osc->freq != 0UL) && (rate != osc->freq)) { 209 ERROR("Already initialized oscillator. freq = %lu\n", 210 osc->freq); 211 return -EINVAL; 212 } 213 214 osc->freq = rate; 215 *orate = osc->freq; 216 217 return 0; 218 } 219 220 static int set_clk_freq(const struct s32cc_clk_obj *module, unsigned long rate, 221 unsigned long *orate, unsigned int *depth) 222 { 223 const struct s32cc_clk *clk = s32cc_obj2clk(module); 224 int ret; 225 226 ret = update_stack_depth(depth); 227 if (ret != 0) { 228 return ret; 229 } 230 231 if ((clk->min_freq != 0UL) && (clk->max_freq != 0UL) && 232 ((rate < clk->min_freq) || (rate > clk->max_freq))) { 233 ERROR("%lu frequency is out of the allowed range: [%lu:%lu]\n", 234 rate, clk->min_freq, clk->max_freq); 235 return -EINVAL; 236 } 237 238 if (clk->module != NULL) { 239 return set_module_rate(clk->module, rate, orate, depth); 240 } 241 242 if (clk->pclock != NULL) { 243 return set_clk_freq(&clk->pclock->desc, rate, orate, depth); 244 } 245 246 return -EINVAL; 247 } 248 249 static int set_pll_freq(const struct s32cc_clk_obj *module, unsigned long rate, 250 unsigned long *orate, unsigned int *depth) 251 { 252 struct s32cc_pll *pll = s32cc_obj2pll(module); 253 int ret; 254 255 ret = update_stack_depth(depth); 256 if (ret != 0) { 257 return ret; 258 } 259 260 if ((pll->vco_freq != 0UL) && (pll->vco_freq != rate)) { 261 ERROR("PLL frequency was already set\n"); 262 return -EINVAL; 263 } 264 265 pll->vco_freq = rate; 266 *orate = pll->vco_freq; 267 268 return 0; 269 } 270 271 static int set_pll_div_freq(const struct s32cc_clk_obj *module, unsigned long rate, 272 unsigned long *orate, unsigned int *depth) 273 { 274 struct s32cc_pll_out_div *pdiv = s32cc_obj2plldiv(module); 275 const struct s32cc_pll *pll; 276 unsigned long prate, dc; 277 int ret; 278 279 ret = update_stack_depth(depth); 280 if (ret != 0) { 281 return ret; 282 } 283 284 if (pdiv->parent == NULL) { 285 ERROR("Failed to identify PLL divider's parent\n"); 286 return -EINVAL; 287 } 288 289 pll = s32cc_obj2pll(pdiv->parent); 290 if (pll == NULL) { 291 ERROR("The parent of the PLL DIV is invalid\n"); 292 return -EINVAL; 293 } 294 295 prate = pll->vco_freq; 296 297 /** 298 * The PLL is not initialized yet, so let's take a risk 299 * and accept the proposed rate. 300 */ 301 if (prate == 0UL) { 302 pdiv->freq = rate; 303 *orate = rate; 304 return 0; 305 } 306 307 /* Decline in case the rate cannot fit PLL's requirements. */ 308 dc = prate / rate; 309 if ((prate / dc) != rate) { 310 return -EINVAL; 311 } 312 313 pdiv->freq = rate; 314 *orate = pdiv->freq; 315 316 return 0; 317 } 318 319 static int set_module_rate(const struct s32cc_clk_obj *module, 320 unsigned long rate, unsigned long *orate, 321 unsigned int *depth) 322 { 323 int ret = 0; 324 325 ret = update_stack_depth(depth); 326 if (ret != 0) { 327 return ret; 328 } 329 330 switch (module->type) { 331 case s32cc_clk_t: 332 ret = set_clk_freq(module, rate, orate, depth); 333 break; 334 case s32cc_osc_t: 335 ret = set_osc_freq(module, rate, orate, depth); 336 break; 337 case s32cc_pll_t: 338 ret = set_pll_freq(module, rate, orate, depth); 339 break; 340 case s32cc_pll_out_div_t: 341 ret = set_pll_div_freq(module, rate, orate, depth); 342 break; 343 case s32cc_clkmux_t: 344 case s32cc_shared_clkmux_t: 345 case s32cc_fixed_div_t: 346 ret = -ENOTSUP; 347 break; 348 default: 349 ret = -EINVAL; 350 break; 351 } 352 353 return ret; 354 } 355 356 static int s32cc_clk_set_rate(unsigned long id, unsigned long rate, 357 unsigned long *orate) 358 { 359 unsigned int depth = MAX_STACK_DEPTH; 360 const struct s32cc_clk *clk; 361 int ret; 362 363 clk = s32cc_get_arch_clk(id); 364 if (clk == NULL) { 365 return -EINVAL; 366 } 367 368 ret = set_module_rate(&clk->desc, rate, orate, &depth); 369 if (ret != 0) { 370 ERROR("Failed to set frequency (%lu MHz) for clock %lu\n", 371 rate, id); 372 } 373 374 return ret; 375 } 376 377 static int s32cc_clk_get_parent(unsigned long id) 378 { 379 return -ENOTSUP; 380 } 381 382 static int s32cc_clk_set_parent(unsigned long id, unsigned long parent_id) 383 { 384 const struct s32cc_clk *parent; 385 const struct s32cc_clk *clk; 386 bool valid_source = false; 387 struct s32cc_clkmux *mux; 388 uint8_t i; 389 390 clk = s32cc_get_arch_clk(id); 391 if (clk == NULL) { 392 return -EINVAL; 393 } 394 395 parent = s32cc_get_arch_clk(parent_id); 396 if (parent == NULL) { 397 return -EINVAL; 398 } 399 400 if (!is_s32cc_clk_mux(clk)) { 401 ERROR("Clock %lu is not a mux\n", id); 402 return -EINVAL; 403 } 404 405 mux = s32cc_clk2mux(clk); 406 if (mux == NULL) { 407 ERROR("Failed to cast clock %lu to clock mux\n", id); 408 return -EINVAL; 409 } 410 411 for (i = 0; i < mux->nclks; i++) { 412 if (mux->clkids[i] == parent_id) { 413 valid_source = true; 414 break; 415 } 416 } 417 418 if (!valid_source) { 419 ERROR("Clock %lu is not a valid clock for mux %lu\n", 420 parent_id, id); 421 return -EINVAL; 422 } 423 424 mux->source_id = parent_id; 425 426 return 0; 427 } 428 429 void s32cc_clk_register_drv(void) 430 { 431 static const struct clk_ops s32cc_clk_ops = { 432 .enable = s32cc_clk_enable, 433 .disable = s32cc_clk_disable, 434 .is_enabled = s32cc_clk_is_enabled, 435 .get_rate = s32cc_clk_get_rate, 436 .set_rate = s32cc_clk_set_rate, 437 .get_parent = s32cc_clk_get_parent, 438 .set_parent = s32cc_clk_set_parent, 439 }; 440 441 clk_register(&s32cc_clk_ops); 442 } 443 444