1 /* 2 * Copyright (C) 2013 DENX Software Engineering 3 * 4 * Gerhard Sittig, <gsi@denx.de> 5 * 6 * common clock driver support for the MPC512x platform 7 * 8 * This is free software; you can redistribute it and/or modify it 9 * under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or 11 * (at your option) any later version. 12 */ 13 14 #include <linux/bitops.h> 15 #include <linux/clk-provider.h> 16 #include <linux/clkdev.h> 17 #include <linux/device.h> 18 #include <linux/errno.h> 19 #include <linux/io.h> 20 #include <linux/of.h> 21 #include <linux/of_address.h> 22 23 #include <asm/mpc5121.h> 24 #include <dt-bindings/clock/mpc512x-clock.h> 25 26 #include "mpc512x.h" /* our public mpc5121_clk_init() API */ 27 28 /* helpers to keep the MCLK intermediates "somewhere" in our table */ 29 enum { 30 MCLK_IDX_MUX0, 31 MCLK_IDX_EN0, 32 MCLK_IDX_DIV0, 33 MCLK_MAX_IDX, 34 }; 35 36 #define NR_PSCS 12 37 #define NR_MSCANS 4 38 #define NR_SPDIFS 1 39 #define NR_OUTCLK 4 40 #define NR_MCLKS (NR_PSCS + NR_MSCANS + NR_SPDIFS + NR_OUTCLK) 41 42 /* extend the public set of clocks by adding internal slots for management */ 43 enum { 44 /* arrange for adjacent numbers after the public set */ 45 MPC512x_CLK_START_PRIVATE = MPC512x_CLK_LAST_PUBLIC, 46 /* clocks which aren't announced to the public */ 47 MPC512x_CLK_DDR, 48 MPC512x_CLK_MEM, 49 MPC512x_CLK_IIM, 50 /* intermediates in div+gate combos or fractional dividers */ 51 MPC512x_CLK_DDR_UG, 52 MPC512x_CLK_SDHC_x4, 53 MPC512x_CLK_SDHC_UG, 54 MPC512x_CLK_SDHC2_UG, 55 MPC512x_CLK_DIU_x4, 56 MPC512x_CLK_DIU_UG, 57 MPC512x_CLK_MBX_BUS_UG, 58 MPC512x_CLK_MBX_UG, 59 MPC512x_CLK_MBX_3D_UG, 60 MPC512x_CLK_PCI_UG, 61 MPC512x_CLK_NFC_UG, 62 MPC512x_CLK_LPC_UG, 63 MPC512x_CLK_SPDIF_TX_IN, 64 /* intermediates for the mux+gate+div+mux MCLK generation */ 65 MPC512x_CLK_MCLKS_FIRST, 66 MPC512x_CLK_MCLKS_LAST = MPC512x_CLK_MCLKS_FIRST 67 + NR_MCLKS * MCLK_MAX_IDX, 68 /* internal, symbolic spec for the number of slots */ 69 MPC512x_CLK_LAST_PRIVATE, 70 }; 71 72 /* data required for the OF clock provider registration */ 73 static struct clk *clks[MPC512x_CLK_LAST_PRIVATE]; 74 static struct clk_onecell_data clk_data; 75 76 /* CCM register access */ 77 static struct mpc512x_ccm __iomem *clkregs; 78 static DEFINE_SPINLOCK(clklock); 79 80 /* SoC variants {{{ */ 81 82 /* 83 * tell SoC variants apart as they are rather similar yet not identical, 84 * cache the result in an enum to not repeatedly run the expensive OF test 85 * 86 * MPC5123 is an MPC5121 without the MBX graphics accelerator 87 * 88 * MPC5125 has many more differences: no MBX, no AXE, no VIU, no SPDIF, 89 * no PATA, no SATA, no PCI, two FECs (of different compatibility name), 90 * only 10 PSCs (of different compatibility name), two SDHCs, different 91 * NFC IP block, output clocks, system PLL status query, different CPMF 92 * interpretation, no CFM, different fourth PSC/CAN mux0 input -- yet 93 * those differences can get folded into this clock provider support 94 * code and don't warrant a separate highly redundant implementation 95 */ 96 97 static enum soc_type { 98 MPC512x_SOC_MPC5121, 99 MPC512x_SOC_MPC5123, 100 MPC512x_SOC_MPC5125, 101 } soc; 102 103 static void mpc512x_clk_determine_soc(void) 104 { 105 if (of_machine_is_compatible("fsl,mpc5121")) { 106 soc = MPC512x_SOC_MPC5121; 107 return; 108 } 109 if (of_machine_is_compatible("fsl,mpc5123")) { 110 soc = MPC512x_SOC_MPC5123; 111 return; 112 } 113 if (of_machine_is_compatible("fsl,mpc5125")) { 114 soc = MPC512x_SOC_MPC5125; 115 return; 116 } 117 } 118 119 static bool soc_has_mbx(void) 120 { 121 if (soc == MPC512x_SOC_MPC5121) 122 return true; 123 return false; 124 } 125 126 static bool soc_has_axe(void) 127 { 128 if (soc == MPC512x_SOC_MPC5125) 129 return false; 130 return true; 131 } 132 133 static bool soc_has_viu(void) 134 { 135 if (soc == MPC512x_SOC_MPC5125) 136 return false; 137 return true; 138 } 139 140 static bool soc_has_spdif(void) 141 { 142 if (soc == MPC512x_SOC_MPC5125) 143 return false; 144 return true; 145 } 146 147 static bool soc_has_pata(void) 148 { 149 if (soc == MPC512x_SOC_MPC5125) 150 return false; 151 return true; 152 } 153 154 static bool soc_has_sata(void) 155 { 156 if (soc == MPC512x_SOC_MPC5125) 157 return false; 158 return true; 159 } 160 161 static bool soc_has_pci(void) 162 { 163 if (soc == MPC512x_SOC_MPC5125) 164 return false; 165 return true; 166 } 167 168 static bool soc_has_fec2(void) 169 { 170 if (soc == MPC512x_SOC_MPC5125) 171 return true; 172 return false; 173 } 174 175 static int soc_max_pscnum(void) 176 { 177 if (soc == MPC512x_SOC_MPC5125) 178 return 10; 179 return 12; 180 } 181 182 static bool soc_has_sdhc2(void) 183 { 184 if (soc == MPC512x_SOC_MPC5125) 185 return true; 186 return false; 187 } 188 189 static bool soc_has_nfc_5125(void) 190 { 191 if (soc == MPC512x_SOC_MPC5125) 192 return true; 193 return false; 194 } 195 196 static bool soc_has_outclk(void) 197 { 198 if (soc == MPC512x_SOC_MPC5125) 199 return true; 200 return false; 201 } 202 203 static bool soc_has_cpmf_0_bypass(void) 204 { 205 if (soc == MPC512x_SOC_MPC5125) 206 return true; 207 return false; 208 } 209 210 static bool soc_has_mclk_mux0_canin(void) 211 { 212 if (soc == MPC512x_SOC_MPC5125) 213 return true; 214 return false; 215 } 216 217 /* }}} SoC variants */ 218 /* common clk API wrappers {{{ */ 219 220 /* convenience wrappers around the common clk API */ 221 static inline struct clk *mpc512x_clk_fixed(const char *name, int rate) 222 { 223 return clk_register_fixed_rate(NULL, name, NULL, CLK_IS_ROOT, rate); 224 } 225 226 static inline struct clk *mpc512x_clk_factor( 227 const char *name, const char *parent_name, 228 int mul, int div) 229 { 230 int clkflags; 231 232 clkflags = CLK_SET_RATE_PARENT; 233 return clk_register_fixed_factor(NULL, name, parent_name, clkflags, 234 mul, div); 235 } 236 237 static inline struct clk *mpc512x_clk_divider( 238 const char *name, const char *parent_name, u8 clkflags, 239 u32 __iomem *reg, u8 pos, u8 len, int divflags) 240 { 241 return clk_register_divider(NULL, name, parent_name, clkflags, 242 reg, pos, len, divflags, &clklock); 243 } 244 245 static inline struct clk *mpc512x_clk_divtable( 246 const char *name, const char *parent_name, 247 u32 __iomem *reg, u8 pos, u8 len, 248 const struct clk_div_table *divtab) 249 { 250 u8 divflags; 251 252 divflags = 0; 253 return clk_register_divider_table(NULL, name, parent_name, 0, 254 reg, pos, len, divflags, 255 divtab, &clklock); 256 } 257 258 static inline struct clk *mpc512x_clk_gated( 259 const char *name, const char *parent_name, 260 u32 __iomem *reg, u8 pos) 261 { 262 int clkflags; 263 264 clkflags = CLK_SET_RATE_PARENT; 265 return clk_register_gate(NULL, name, parent_name, clkflags, 266 reg, pos, 0, &clklock); 267 } 268 269 static inline struct clk *mpc512x_clk_muxed(const char *name, 270 const char **parent_names, int parent_count, 271 u32 __iomem *reg, u8 pos, u8 len) 272 { 273 int clkflags; 274 u8 muxflags; 275 276 clkflags = CLK_SET_RATE_PARENT; 277 muxflags = 0; 278 return clk_register_mux(NULL, name, 279 parent_names, parent_count, clkflags, 280 reg, pos, len, muxflags, &clklock); 281 } 282 283 /* }}} common clk API wrappers */ 284 285 /* helper to isolate a bit field from a register */ 286 static inline int get_bit_field(uint32_t __iomem *reg, uint8_t pos, uint8_t len) 287 { 288 uint32_t val; 289 290 val = in_be32(reg); 291 val >>= pos; 292 val &= (1 << len) - 1; 293 return val; 294 } 295 296 /* get the SPMF and translate it into the "sys pll" multiplier */ 297 static int get_spmf_mult(void) 298 { 299 static int spmf_to_mult[] = { 300 68, 1, 12, 16, 20, 24, 28, 32, 301 36, 40, 44, 48, 52, 56, 60, 64, 302 }; 303 int spmf; 304 305 spmf = get_bit_field(&clkregs->spmr, 24, 4); 306 return spmf_to_mult[spmf]; 307 } 308 309 /* 310 * get the SYS_DIV value and translate it into a divide factor 311 * 312 * values returned from here are a multiple of the real factor since the 313 * divide ratio is fractional 314 */ 315 static int get_sys_div_x2(void) 316 { 317 static int sysdiv_code_to_x2[] = { 318 4, 5, 6, 7, 8, 9, 10, 14, 319 12, 16, 18, 22, 20, 24, 26, 30, 320 28, 32, 34, 38, 36, 40, 42, 46, 321 44, 48, 50, 54, 52, 56, 58, 62, 322 60, 64, 66, 323 }; 324 int divcode; 325 326 divcode = get_bit_field(&clkregs->scfr2, 26, 6); 327 return sysdiv_code_to_x2[divcode]; 328 } 329 330 /* 331 * get the CPMF value and translate it into a multiplier factor 332 * 333 * values returned from here are a multiple of the real factor since the 334 * multiplier ratio is fractional 335 */ 336 static int get_cpmf_mult_x2(void) 337 { 338 static int cpmf_to_mult_x36[] = { 339 /* 0b000 is "times 36" */ 340 72, 2, 2, 3, 4, 5, 6, 7, 341 }; 342 static int cpmf_to_mult_0by[] = { 343 /* 0b000 is "bypass" */ 344 2, 2, 2, 3, 4, 5, 6, 7, 345 }; 346 347 int *cpmf_to_mult; 348 int cpmf; 349 350 cpmf = get_bit_field(&clkregs->spmr, 16, 4); 351 if (soc_has_cpmf_0_bypass()) 352 cpmf_to_mult = cpmf_to_mult_0by; 353 else 354 cpmf_to_mult = cpmf_to_mult_x36; 355 return cpmf_to_mult[cpmf]; 356 } 357 358 /* 359 * some of the clock dividers do scale in a linear way, yet not all of 360 * their bit combinations are legal; use a divider table to get a 361 * resulting set of applicable divider values 362 */ 363 364 /* applies to the IPS_DIV, and PCI_DIV values */ 365 static struct clk_div_table divtab_2346[] = { 366 { .val = 2, .div = 2, }, 367 { .val = 3, .div = 3, }, 368 { .val = 4, .div = 4, }, 369 { .val = 6, .div = 6, }, 370 { .div = 0, }, 371 }; 372 373 /* applies to the MBX_DIV, LPC_DIV, and NFC_DIV values */ 374 static struct clk_div_table divtab_1234[] = { 375 { .val = 1, .div = 1, }, 376 { .val = 2, .div = 2, }, 377 { .val = 3, .div = 3, }, 378 { .val = 4, .div = 4, }, 379 { .div = 0, }, 380 }; 381 382 static int get_freq_from_dt(char *propname) 383 { 384 struct device_node *np; 385 const unsigned int *prop; 386 int val; 387 388 val = 0; 389 np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-immr"); 390 if (np) { 391 prop = of_get_property(np, propname, NULL); 392 if (prop) 393 val = *prop; 394 of_node_put(np); 395 } 396 return val; 397 } 398 399 static void mpc512x_clk_preset_data(void) 400 { 401 size_t i; 402 403 for (i = 0; i < ARRAY_SIZE(clks); i++) 404 clks[i] = ERR_PTR(-ENODEV); 405 } 406 407 /* 408 * - receives the "bus frequency" from the caller (that's the IPS clock 409 * rate, the historical source of clock information) 410 * - fetches the system PLL multiplier and divider values as well as the 411 * IPS divider value from hardware 412 * - determines the REF clock rate either from the XTAL/OSC spec (if 413 * there is a device tree node describing the oscillator) or from the 414 * IPS bus clock (supported for backwards compatibility, such that 415 * setups without XTAL/OSC specs keep working) 416 * - creates the "ref" clock item in the clock tree, such that 417 * subsequent code can create the remainder of the hierarchy (REF -> 418 * SYS -> CSB -> IPS) from the REF clock rate and the returned mul/div 419 * values 420 */ 421 static void mpc512x_clk_setup_ref_clock(struct device_node *np, int bus_freq, 422 int *sys_mul, int *sys_div, 423 int *ips_div) 424 { 425 struct clk *osc_clk; 426 int calc_freq; 427 428 /* fetch mul/div factors from the hardware */ 429 *sys_mul = get_spmf_mult(); 430 *sys_mul *= 2; /* compensate for the fractional divider */ 431 *sys_div = get_sys_div_x2(); 432 *ips_div = get_bit_field(&clkregs->scfr1, 23, 3); 433 434 /* lookup the oscillator clock for its rate */ 435 osc_clk = of_clk_get_by_name(np, "osc"); 436 437 /* 438 * either descend from OSC to REF (and in bypassing verify the 439 * IPS rate), or backtrack from IPS and multiplier values that 440 * were fetched from hardware to REF and thus to the OSC value 441 * 442 * in either case the REF clock gets created here and the 443 * remainder of the clock tree can get spanned from there 444 */ 445 if (!IS_ERR(osc_clk)) { 446 clks[MPC512x_CLK_REF] = mpc512x_clk_factor("ref", "osc", 1, 1); 447 calc_freq = clk_get_rate(clks[MPC512x_CLK_REF]); 448 calc_freq *= *sys_mul; 449 calc_freq /= *sys_div; 450 calc_freq /= 2; 451 calc_freq /= *ips_div; 452 if (bus_freq && calc_freq != bus_freq) 453 pr_warn("calc rate %d != OF spec %d\n", 454 calc_freq, bus_freq); 455 } else { 456 calc_freq = bus_freq; /* start with IPS */ 457 calc_freq *= *ips_div; /* IPS -> CSB */ 458 calc_freq *= 2; /* CSB -> SYS */ 459 calc_freq *= *sys_div; /* SYS -> PLL out */ 460 calc_freq /= *sys_mul; /* PLL out -> REF == OSC */ 461 clks[MPC512x_CLK_REF] = mpc512x_clk_fixed("ref", calc_freq); 462 } 463 } 464 465 /* MCLK helpers {{{ */ 466 467 /* 468 * helper code for the MCLK subtree setup 469 * 470 * the overview in section 5.2.4 of the MPC5121e Reference Manual rev4 471 * suggests that all instances of the "PSC clock generation" are equal, 472 * and that one might re-use the PSC setup for MSCAN clock generation 473 * (section 5.2.5) as well, at least the logic if not the data for 474 * description 475 * 476 * the details (starting at page 5-20) show differences in the specific 477 * inputs of the first mux stage ("can clk in", "spdif tx"), and the 478 * factual non-availability of the second mux stage (it's present yet 479 * only one input is valid) 480 * 481 * the MSCAN clock related registers (starting at page 5-35) all 482 * reference "spdif clk" at the first mux stage and don't mention any 483 * "can clk" at all, which somehow is unexpected 484 * 485 * TODO re-check the document, and clarify whether the RM is correct in 486 * the overview or in the details, and whether the difference is a 487 * clipboard induced error or results from chip revisions 488 * 489 * it turns out that the RM rev4 as of 2012-06 talks about "can" for the 490 * PSCs while RM rev3 as of 2008-10 talks about "spdif", so I guess that 491 * first a doc update is required which better reflects reality in the 492 * SoC before the implementation should follow while no questions remain 493 */ 494 495 /* 496 * note that this declaration raises a checkpatch warning, but 497 * it's the very data type dictated by <linux/clk-provider.h>, 498 * "fixing" this warning will break compilation 499 */ 500 static const char *parent_names_mux0_spdif[] = { 501 "sys", "ref", "psc-mclk-in", "spdif-tx", 502 }; 503 504 static const char *parent_names_mux0_canin[] = { 505 "sys", "ref", "psc-mclk-in", "can-clk-in", 506 }; 507 508 enum mclk_type { 509 MCLK_TYPE_PSC, 510 MCLK_TYPE_MSCAN, 511 MCLK_TYPE_SPDIF, 512 MCLK_TYPE_OUTCLK, 513 }; 514 515 struct mclk_setup_data { 516 enum mclk_type type; 517 bool has_mclk1; 518 const char *name_mux0; 519 const char *name_en0; 520 const char *name_div0; 521 const char *parent_names_mux1[2]; 522 const char *name_mclk; 523 }; 524 525 #define MCLK_SETUP_DATA_PSC(id) { \ 526 MCLK_TYPE_PSC, 0, \ 527 "psc" #id "-mux0", \ 528 "psc" #id "-en0", \ 529 "psc" #id "_mclk_div", \ 530 { "psc" #id "_mclk_div", "dummy", }, \ 531 "psc" #id "_mclk", \ 532 } 533 534 #define MCLK_SETUP_DATA_MSCAN(id) { \ 535 MCLK_TYPE_MSCAN, 0, \ 536 "mscan" #id "-mux0", \ 537 "mscan" #id "-en0", \ 538 "mscan" #id "_mclk_div", \ 539 { "mscan" #id "_mclk_div", "dummy", }, \ 540 "mscan" #id "_mclk", \ 541 } 542 543 #define MCLK_SETUP_DATA_SPDIF { \ 544 MCLK_TYPE_SPDIF, 1, \ 545 "spdif-mux0", \ 546 "spdif-en0", \ 547 "spdif_mclk_div", \ 548 { "spdif_mclk_div", "spdif-rx", }, \ 549 "spdif_mclk", \ 550 } 551 552 #define MCLK_SETUP_DATA_OUTCLK(id) { \ 553 MCLK_TYPE_OUTCLK, 0, \ 554 "out" #id "-mux0", \ 555 "out" #id "-en0", \ 556 "out" #id "_mclk_div", \ 557 { "out" #id "_mclk_div", "dummy", }, \ 558 "out" #id "_clk", \ 559 } 560 561 static struct mclk_setup_data mclk_psc_data[] = { 562 MCLK_SETUP_DATA_PSC(0), 563 MCLK_SETUP_DATA_PSC(1), 564 MCLK_SETUP_DATA_PSC(2), 565 MCLK_SETUP_DATA_PSC(3), 566 MCLK_SETUP_DATA_PSC(4), 567 MCLK_SETUP_DATA_PSC(5), 568 MCLK_SETUP_DATA_PSC(6), 569 MCLK_SETUP_DATA_PSC(7), 570 MCLK_SETUP_DATA_PSC(8), 571 MCLK_SETUP_DATA_PSC(9), 572 MCLK_SETUP_DATA_PSC(10), 573 MCLK_SETUP_DATA_PSC(11), 574 }; 575 576 static struct mclk_setup_data mclk_mscan_data[] = { 577 MCLK_SETUP_DATA_MSCAN(0), 578 MCLK_SETUP_DATA_MSCAN(1), 579 MCLK_SETUP_DATA_MSCAN(2), 580 MCLK_SETUP_DATA_MSCAN(3), 581 }; 582 583 static struct mclk_setup_data mclk_spdif_data[] = { 584 MCLK_SETUP_DATA_SPDIF, 585 }; 586 587 static struct mclk_setup_data mclk_outclk_data[] = { 588 MCLK_SETUP_DATA_OUTCLK(0), 589 MCLK_SETUP_DATA_OUTCLK(1), 590 MCLK_SETUP_DATA_OUTCLK(2), 591 MCLK_SETUP_DATA_OUTCLK(3), 592 }; 593 594 /* setup the MCLK clock subtree of an individual PSC/MSCAN/SPDIF */ 595 static void mpc512x_clk_setup_mclk(struct mclk_setup_data *entry, size_t idx) 596 { 597 size_t clks_idx_pub, clks_idx_int; 598 u32 __iomem *mccr_reg; /* MCLK control register (mux, en, div) */ 599 int div; 600 601 /* derive a few parameters from the component type and index */ 602 switch (entry->type) { 603 case MCLK_TYPE_PSC: 604 clks_idx_pub = MPC512x_CLK_PSC0_MCLK + idx; 605 clks_idx_int = MPC512x_CLK_MCLKS_FIRST 606 + (idx) * MCLK_MAX_IDX; 607 mccr_reg = &clkregs->psc_ccr[idx]; 608 break; 609 case MCLK_TYPE_MSCAN: 610 clks_idx_pub = MPC512x_CLK_MSCAN0_MCLK + idx; 611 clks_idx_int = MPC512x_CLK_MCLKS_FIRST 612 + (NR_PSCS + idx) * MCLK_MAX_IDX; 613 mccr_reg = &clkregs->mscan_ccr[idx]; 614 break; 615 case MCLK_TYPE_SPDIF: 616 clks_idx_pub = MPC512x_CLK_SPDIF_MCLK; 617 clks_idx_int = MPC512x_CLK_MCLKS_FIRST 618 + (NR_PSCS + NR_MSCANS) * MCLK_MAX_IDX; 619 mccr_reg = &clkregs->spccr; 620 break; 621 case MCLK_TYPE_OUTCLK: 622 clks_idx_pub = MPC512x_CLK_OUT0_CLK + idx; 623 clks_idx_int = MPC512x_CLK_MCLKS_FIRST 624 + (NR_PSCS + NR_MSCANS + NR_SPDIFS + idx) 625 * MCLK_MAX_IDX; 626 mccr_reg = &clkregs->out_ccr[idx]; 627 break; 628 default: 629 return; 630 } 631 632 /* 633 * this was grabbed from the PPC_CLOCK implementation, which 634 * enforced a specific MCLK divider while the clock was gated 635 * during setup (that's a documented hardware requirement) 636 * 637 * the PPC_CLOCK implementation might even have violated the 638 * "MCLK <= IPS" constraint, the fixed divider value of 1 639 * results in a divider of 2 and thus MCLK = SYS/2 which equals 640 * CSB which is greater than IPS; the serial port setup may have 641 * adjusted the divider which the clock setup might have left in 642 * an undesirable state 643 * 644 * initial setup is: 645 * - MCLK 0 from SYS 646 * - MCLK DIV such to not exceed the IPS clock 647 * - MCLK 0 enabled 648 * - MCLK 1 from MCLK DIV 649 */ 650 div = clk_get_rate(clks[MPC512x_CLK_SYS]); 651 div /= clk_get_rate(clks[MPC512x_CLK_IPS]); 652 out_be32(mccr_reg, (0 << 16)); 653 out_be32(mccr_reg, (0 << 16) | ((div - 1) << 17)); 654 out_be32(mccr_reg, (1 << 16) | ((div - 1) << 17)); 655 656 /* 657 * create the 'struct clk' items of the MCLK's clock subtree 658 * 659 * note that by design we always create all nodes and won't take 660 * shortcuts here, because 661 * - the "internal" MCLK_DIV and MCLK_OUT signal in turn are 662 * selectable inputs to the CFM while those who "actually use" 663 * the PSC/MSCAN/SPDIF (serial drivers et al) need the MCLK 664 * for their bitrate 665 * - in the absence of "aliases" for clocks we need to create 666 * individial 'struct clk' items for whatever might get 667 * referenced or looked up, even if several of those items are 668 * identical from the logical POV (their rate value) 669 * - for easier future maintenance and for better reflection of 670 * the SoC's documentation, it appears appropriate to generate 671 * clock items even for those muxers which actually are NOPs 672 * (those with two inputs of which one is reserved) 673 */ 674 clks[clks_idx_int + MCLK_IDX_MUX0] = mpc512x_clk_muxed( 675 entry->name_mux0, 676 soc_has_mclk_mux0_canin() 677 ? &parent_names_mux0_canin[0] 678 : &parent_names_mux0_spdif[0], 679 ARRAY_SIZE(parent_names_mux0_spdif), 680 mccr_reg, 14, 2); 681 clks[clks_idx_int + MCLK_IDX_EN0] = mpc512x_clk_gated( 682 entry->name_en0, entry->name_mux0, 683 mccr_reg, 16); 684 clks[clks_idx_int + MCLK_IDX_DIV0] = mpc512x_clk_divider( 685 entry->name_div0, 686 entry->name_en0, CLK_SET_RATE_GATE, 687 mccr_reg, 17, 15, 0); 688 if (entry->has_mclk1) { 689 clks[clks_idx_pub] = mpc512x_clk_muxed( 690 entry->name_mclk, 691 &entry->parent_names_mux1[0], 692 ARRAY_SIZE(entry->parent_names_mux1), 693 mccr_reg, 7, 1); 694 } else { 695 clks[clks_idx_pub] = mpc512x_clk_factor( 696 entry->name_mclk, 697 entry->parent_names_mux1[0], 698 1, 1); 699 } 700 } 701 702 /* }}} MCLK helpers */ 703 704 static void mpc512x_clk_setup_clock_tree(struct device_node *np, int busfreq) 705 { 706 int sys_mul, sys_div, ips_div; 707 int mul, div; 708 size_t mclk_idx; 709 int freq; 710 711 /* 712 * developer's notes: 713 * - consider whether to handle clocks which have both gates and 714 * dividers via intermediates or by means of composites 715 * - fractional dividers appear to not map well to composites 716 * since they can be seen as a fixed multiplier and an 717 * adjustable divider, while composites can only combine at 718 * most one of a mux, div, and gate each into one 'struct clk' 719 * item 720 * - PSC/MSCAN/SPDIF clock generation OTOH already is very 721 * specific and cannot get mapped to componsites (at least not 722 * a single one, maybe two of them, but then some of these 723 * intermediate clock signals get referenced elsewhere (e.g. 724 * in the clock frequency measurement, CFM) and thus need 725 * publicly available names 726 * - the current source layout appropriately reflects the 727 * hardware setup, and it works, so it's questionable whether 728 * further changes will result in big enough a benefit 729 */ 730 731 /* regardless of whether XTAL/OSC exists, have REF created */ 732 mpc512x_clk_setup_ref_clock(np, busfreq, &sys_mul, &sys_div, &ips_div); 733 734 /* now setup the REF -> SYS -> CSB -> IPS hierarchy */ 735 clks[MPC512x_CLK_SYS] = mpc512x_clk_factor("sys", "ref", 736 sys_mul, sys_div); 737 clks[MPC512x_CLK_CSB] = mpc512x_clk_factor("csb", "sys", 1, 2); 738 clks[MPC512x_CLK_IPS] = mpc512x_clk_divtable("ips", "csb", 739 &clkregs->scfr1, 23, 3, 740 divtab_2346); 741 /* now setup anything below SYS and CSB and IPS */ 742 743 clks[MPC512x_CLK_DDR_UG] = mpc512x_clk_factor("ddr-ug", "sys", 1, 2); 744 745 /* 746 * the Reference Manual discusses that for SDHC only even divide 747 * ratios are supported because clock domain synchronization 748 * between 'per' and 'ipg' is broken; 749 * keep the divider's bit 0 cleared (per reset value), and only 750 * allow to setup the divider's bits 7:1, which results in that 751 * only even divide ratios can get configured upon rate changes; 752 * keep the "x4" name because this bit shift hack is an internal 753 * implementation detail, the "fractional divider with quarters" 754 * semantics remains 755 */ 756 clks[MPC512x_CLK_SDHC_x4] = mpc512x_clk_factor("sdhc-x4", "csb", 2, 1); 757 clks[MPC512x_CLK_SDHC_UG] = mpc512x_clk_divider("sdhc-ug", "sdhc-x4", 0, 758 &clkregs->scfr2, 1, 7, 759 CLK_DIVIDER_ONE_BASED); 760 if (soc_has_sdhc2()) { 761 clks[MPC512x_CLK_SDHC2_UG] = mpc512x_clk_divider( 762 "sdhc2-ug", "sdhc-x4", 0, &clkregs->scfr2, 763 9, 7, CLK_DIVIDER_ONE_BASED); 764 } 765 766 clks[MPC512x_CLK_DIU_x4] = mpc512x_clk_factor("diu-x4", "csb", 4, 1); 767 clks[MPC512x_CLK_DIU_UG] = mpc512x_clk_divider("diu-ug", "diu-x4", 0, 768 &clkregs->scfr1, 0, 8, 769 CLK_DIVIDER_ONE_BASED); 770 771 /* 772 * the "power architecture PLL" was setup from data which was 773 * sampled from the reset config word, at this point in time the 774 * configuration can be considered fixed and read only (i.e. no 775 * longer adjustable, or no longer in need of adjustment), which 776 * is why we don't register a PLL here but assume fixed factors 777 */ 778 mul = get_cpmf_mult_x2(); 779 div = 2; /* compensate for the fractional factor */ 780 clks[MPC512x_CLK_E300] = mpc512x_clk_factor("e300", "csb", mul, div); 781 782 if (soc_has_mbx()) { 783 clks[MPC512x_CLK_MBX_BUS_UG] = mpc512x_clk_factor( 784 "mbx-bus-ug", "csb", 1, 2); 785 clks[MPC512x_CLK_MBX_UG] = mpc512x_clk_divtable( 786 "mbx-ug", "mbx-bus-ug", &clkregs->scfr1, 787 14, 3, divtab_1234); 788 clks[MPC512x_CLK_MBX_3D_UG] = mpc512x_clk_factor( 789 "mbx-3d-ug", "mbx-ug", 1, 1); 790 } 791 if (soc_has_pci()) { 792 clks[MPC512x_CLK_PCI_UG] = mpc512x_clk_divtable( 793 "pci-ug", "csb", &clkregs->scfr1, 794 20, 3, divtab_2346); 795 } 796 if (soc_has_nfc_5125()) { 797 /* 798 * XXX TODO implement 5125 NFC clock setup logic, 799 * with high/low period counters in clkregs->scfr3, 800 * currently there are no users so it's ENOIMPL 801 */ 802 clks[MPC512x_CLK_NFC_UG] = ERR_PTR(-ENOTSUPP); 803 } else { 804 clks[MPC512x_CLK_NFC_UG] = mpc512x_clk_divtable( 805 "nfc-ug", "ips", &clkregs->scfr1, 806 8, 3, divtab_1234); 807 } 808 clks[MPC512x_CLK_LPC_UG] = mpc512x_clk_divtable("lpc-ug", "ips", 809 &clkregs->scfr1, 11, 3, 810 divtab_1234); 811 812 clks[MPC512x_CLK_LPC] = mpc512x_clk_gated("lpc", "lpc-ug", 813 &clkregs->sccr1, 30); 814 clks[MPC512x_CLK_NFC] = mpc512x_clk_gated("nfc", "nfc-ug", 815 &clkregs->sccr1, 29); 816 if (soc_has_pata()) { 817 clks[MPC512x_CLK_PATA] = mpc512x_clk_gated( 818 "pata", "ips", &clkregs->sccr1, 28); 819 } 820 /* for PSCs there is a "registers" gate and a bitrate MCLK subtree */ 821 for (mclk_idx = 0; mclk_idx < soc_max_pscnum(); mclk_idx++) { 822 char name[12]; 823 snprintf(name, sizeof(name), "psc%d", mclk_idx); 824 clks[MPC512x_CLK_PSC0 + mclk_idx] = mpc512x_clk_gated( 825 name, "ips", &clkregs->sccr1, 27 - mclk_idx); 826 mpc512x_clk_setup_mclk(&mclk_psc_data[mclk_idx], mclk_idx); 827 } 828 clks[MPC512x_CLK_PSC_FIFO] = mpc512x_clk_gated("psc-fifo", "ips", 829 &clkregs->sccr1, 15); 830 if (soc_has_sata()) { 831 clks[MPC512x_CLK_SATA] = mpc512x_clk_gated( 832 "sata", "ips", &clkregs->sccr1, 14); 833 } 834 clks[MPC512x_CLK_FEC] = mpc512x_clk_gated("fec", "ips", 835 &clkregs->sccr1, 13); 836 if (soc_has_pci()) { 837 clks[MPC512x_CLK_PCI] = mpc512x_clk_gated( 838 "pci", "pci-ug", &clkregs->sccr1, 11); 839 } 840 clks[MPC512x_CLK_DDR] = mpc512x_clk_gated("ddr", "ddr-ug", 841 &clkregs->sccr1, 10); 842 if (soc_has_fec2()) { 843 clks[MPC512x_CLK_FEC2] = mpc512x_clk_gated( 844 "fec2", "ips", &clkregs->sccr1, 9); 845 } 846 847 clks[MPC512x_CLK_DIU] = mpc512x_clk_gated("diu", "diu-ug", 848 &clkregs->sccr2, 31); 849 if (soc_has_axe()) { 850 clks[MPC512x_CLK_AXE] = mpc512x_clk_gated( 851 "axe", "csb", &clkregs->sccr2, 30); 852 } 853 clks[MPC512x_CLK_MEM] = mpc512x_clk_gated("mem", "ips", 854 &clkregs->sccr2, 29); 855 clks[MPC512x_CLK_USB1] = mpc512x_clk_gated("usb1", "csb", 856 &clkregs->sccr2, 28); 857 clks[MPC512x_CLK_USB2] = mpc512x_clk_gated("usb2", "csb", 858 &clkregs->sccr2, 27); 859 clks[MPC512x_CLK_I2C] = mpc512x_clk_gated("i2c", "ips", 860 &clkregs->sccr2, 26); 861 /* MSCAN differs from PSC with just one gate for multiple components */ 862 clks[MPC512x_CLK_BDLC] = mpc512x_clk_gated("bdlc", "ips", 863 &clkregs->sccr2, 25); 864 for (mclk_idx = 0; mclk_idx < ARRAY_SIZE(mclk_mscan_data); mclk_idx++) 865 mpc512x_clk_setup_mclk(&mclk_mscan_data[mclk_idx], mclk_idx); 866 clks[MPC512x_CLK_SDHC] = mpc512x_clk_gated("sdhc", "sdhc-ug", 867 &clkregs->sccr2, 24); 868 /* there is only one SPDIF component, which shares MCLK support code */ 869 if (soc_has_spdif()) { 870 clks[MPC512x_CLK_SPDIF] = mpc512x_clk_gated( 871 "spdif", "ips", &clkregs->sccr2, 23); 872 mpc512x_clk_setup_mclk(&mclk_spdif_data[0], 0); 873 } 874 if (soc_has_mbx()) { 875 clks[MPC512x_CLK_MBX_BUS] = mpc512x_clk_gated( 876 "mbx-bus", "mbx-bus-ug", &clkregs->sccr2, 22); 877 clks[MPC512x_CLK_MBX] = mpc512x_clk_gated( 878 "mbx", "mbx-ug", &clkregs->sccr2, 21); 879 clks[MPC512x_CLK_MBX_3D] = mpc512x_clk_gated( 880 "mbx-3d", "mbx-3d-ug", &clkregs->sccr2, 20); 881 } 882 clks[MPC512x_CLK_IIM] = mpc512x_clk_gated("iim", "csb", 883 &clkregs->sccr2, 19); 884 if (soc_has_viu()) { 885 clks[MPC512x_CLK_VIU] = mpc512x_clk_gated( 886 "viu", "csb", &clkregs->sccr2, 18); 887 } 888 if (soc_has_sdhc2()) { 889 clks[MPC512x_CLK_SDHC2] = mpc512x_clk_gated( 890 "sdhc-2", "sdhc2-ug", &clkregs->sccr2, 17); 891 } 892 893 if (soc_has_outclk()) { 894 size_t idx; /* used as mclk_idx, just to trim line length */ 895 for (idx = 0; idx < ARRAY_SIZE(mclk_outclk_data); idx++) 896 mpc512x_clk_setup_mclk(&mclk_outclk_data[idx], idx); 897 } 898 899 /* 900 * externally provided clocks (when implemented in hardware, 901 * device tree may specify values which otherwise were unknown) 902 */ 903 freq = get_freq_from_dt("psc_mclk_in"); 904 if (!freq) 905 freq = 25000000; 906 clks[MPC512x_CLK_PSC_MCLK_IN] = mpc512x_clk_fixed("psc_mclk_in", freq); 907 if (soc_has_mclk_mux0_canin()) { 908 freq = get_freq_from_dt("can_clk_in"); 909 clks[MPC512x_CLK_CAN_CLK_IN] = mpc512x_clk_fixed( 910 "can_clk_in", freq); 911 } else { 912 freq = get_freq_from_dt("spdif_tx_in"); 913 clks[MPC512x_CLK_SPDIF_TX_IN] = mpc512x_clk_fixed( 914 "spdif_tx_in", freq); 915 freq = get_freq_from_dt("spdif_rx_in"); 916 clks[MPC512x_CLK_SPDIF_TX_IN] = mpc512x_clk_fixed( 917 "spdif_rx_in", freq); 918 } 919 920 /* fixed frequency for AC97, always 24.567MHz */ 921 clks[MPC512x_CLK_AC97] = mpc512x_clk_fixed("ac97", 24567000); 922 923 /* 924 * pre-enable those "internal" clock items which never get 925 * claimed by any peripheral driver, to not have the clock 926 * subsystem disable them late at startup 927 */ 928 clk_prepare_enable(clks[MPC512x_CLK_DUMMY]); 929 clk_prepare_enable(clks[MPC512x_CLK_E300]); /* PowerPC CPU */ 930 clk_prepare_enable(clks[MPC512x_CLK_DDR]); /* DRAM */ 931 clk_prepare_enable(clks[MPC512x_CLK_MEM]); /* SRAM */ 932 clk_prepare_enable(clks[MPC512x_CLK_IPS]); /* SoC periph */ 933 clk_prepare_enable(clks[MPC512x_CLK_LPC]); /* boot media */ 934 } 935 936 /* 937 * registers the set of public clocks (those listed in the dt-bindings/ 938 * header file) for OF lookups, keeps the intermediates private to us 939 */ 940 static void mpc5121_clk_register_of_provider(struct device_node *np) 941 { 942 clk_data.clks = clks; 943 clk_data.clk_num = MPC512x_CLK_LAST_PUBLIC + 1; /* _not_ ARRAY_SIZE() */ 944 of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data); 945 } 946 947 /* 948 * temporary support for the period of time between introduction of CCF 949 * support and the adjustment of peripheral drivers to OF based lookups 950 */ 951 static void mpc5121_clk_provide_migration_support(void) 952 { 953 954 /* 955 * pre-enable those clock items which are not yet appropriately 956 * acquired by their peripheral driver 957 * 958 * the PCI clock cannot get acquired by its peripheral driver, 959 * because for this platform the driver won't probe(), instead 960 * initialization is done from within the .setup_arch() routine 961 * at a point in time where the clock provider has not been 962 * setup yet and thus isn't available yet 963 * 964 * so we "pre-enable" the clock here, to not have the clock 965 * subsystem automatically disable this item in a late init call 966 * 967 * this PCI clock pre-enable workaround only applies when there 968 * are device tree nodes for PCI and thus the peripheral driver 969 * has attached to bridges, otherwise the PCI clock remains 970 * unused and so it gets disabled 971 */ 972 clk_prepare_enable(clks[MPC512x_CLK_PSC3_MCLK]);/* serial console */ 973 if (of_find_compatible_node(NULL, "pci", "fsl,mpc5121-pci")) 974 clk_prepare_enable(clks[MPC512x_CLK_PCI]); 975 } 976 977 /* 978 * those macros are not exactly pretty, but they encapsulate a lot 979 * of copy'n'paste heavy code which is even more ugly, and reduce 980 * the potential for inconsistencies in those many code copies 981 */ 982 #define FOR_NODES(compatname) \ 983 for_each_compatible_node(np, NULL, compatname) 984 985 #define NODE_PREP do { \ 986 of_address_to_resource(np, 0, &res); \ 987 snprintf(devname, sizeof(devname), "%08x.%s", res.start, np->name); \ 988 } while (0) 989 990 #define NODE_CHK(clkname, clkitem, regnode, regflag) do { \ 991 struct clk *clk; \ 992 clk = of_clk_get_by_name(np, clkname); \ 993 if (IS_ERR(clk)) { \ 994 clk = clkitem; \ 995 clk_register_clkdev(clk, clkname, devname); \ 996 if (regnode) \ 997 clk_register_clkdev(clk, clkname, np->name); \ 998 did_register |= DID_REG_ ## regflag; \ 999 pr_debug("clock alias name '%s' for dev '%s' pointer %p\n", \ 1000 clkname, devname, clk); \ 1001 } else { \ 1002 clk_put(clk); \ 1003 } \ 1004 } while (0) 1005 1006 /* 1007 * register source code provided fallback results for clock lookups, 1008 * these get consulted when OF based clock lookup fails (that is in the 1009 * case of not yet adjusted device tree data, where clock related specs 1010 * are missing) 1011 */ 1012 static void mpc5121_clk_provide_backwards_compat(void) 1013 { 1014 enum did_reg_flags { 1015 DID_REG_PSC = BIT(0), 1016 DID_REG_PSCFIFO = BIT(1), 1017 DID_REG_NFC = BIT(2), 1018 DID_REG_CAN = BIT(3), 1019 DID_REG_I2C = BIT(4), 1020 DID_REG_DIU = BIT(5), 1021 DID_REG_VIU = BIT(6), 1022 DID_REG_FEC = BIT(7), 1023 DID_REG_USB = BIT(8), 1024 DID_REG_PATA = BIT(9), 1025 }; 1026 1027 int did_register; 1028 struct device_node *np; 1029 struct resource res; 1030 int idx; 1031 char devname[32]; 1032 1033 did_register = 0; 1034 1035 FOR_NODES(mpc512x_select_psc_compat()) { 1036 NODE_PREP; 1037 idx = (res.start >> 8) & 0xf; 1038 NODE_CHK("ipg", clks[MPC512x_CLK_PSC0 + idx], 0, PSC); 1039 NODE_CHK("mclk", clks[MPC512x_CLK_PSC0_MCLK + idx], 0, PSC); 1040 } 1041 1042 FOR_NODES("fsl,mpc5121-psc-fifo") { 1043 NODE_PREP; 1044 NODE_CHK("ipg", clks[MPC512x_CLK_PSC_FIFO], 1, PSCFIFO); 1045 } 1046 1047 FOR_NODES("fsl,mpc5121-nfc") { 1048 NODE_PREP; 1049 NODE_CHK("ipg", clks[MPC512x_CLK_NFC], 0, NFC); 1050 } 1051 1052 FOR_NODES("fsl,mpc5121-mscan") { 1053 NODE_PREP; 1054 idx = 0; 1055 idx += (res.start & 0x2000) ? 2 : 0; 1056 idx += (res.start & 0x0080) ? 1 : 0; 1057 NODE_CHK("ipg", clks[MPC512x_CLK_BDLC], 0, CAN); 1058 NODE_CHK("mclk", clks[MPC512x_CLK_MSCAN0_MCLK + idx], 0, CAN); 1059 } 1060 1061 /* 1062 * do register the 'ips', 'sys', and 'ref' names globally 1063 * instead of inside each individual CAN node, as there is no 1064 * potential for a name conflict (in contrast to 'ipg' and 'mclk') 1065 */ 1066 if (did_register & DID_REG_CAN) { 1067 clk_register_clkdev(clks[MPC512x_CLK_IPS], "ips", NULL); 1068 clk_register_clkdev(clks[MPC512x_CLK_SYS], "sys", NULL); 1069 clk_register_clkdev(clks[MPC512x_CLK_REF], "ref", NULL); 1070 } 1071 1072 FOR_NODES("fsl,mpc5121-i2c") { 1073 NODE_PREP; 1074 NODE_CHK("ipg", clks[MPC512x_CLK_I2C], 0, I2C); 1075 } 1076 1077 /* 1078 * workaround for the fact that the I2C driver does an "anonymous" 1079 * lookup (NULL name spec, which yields the first clock spec) for 1080 * which we cannot register an alias -- a _global_ 'ipg' alias that 1081 * is not bound to any device name and returns the I2C clock item 1082 * is not a good idea 1083 * 1084 * so we have the lookup in the peripheral driver fail, which is 1085 * silent and non-fatal, and pre-enable the clock item here such 1086 * that register access is possible 1087 * 1088 * see commit b3bfce2b "i2c: mpc: cleanup clock API use" for 1089 * details, adjusting s/NULL/"ipg"/ in i2c-mpc.c would make this 1090 * workaround obsolete 1091 */ 1092 if (did_register & DID_REG_I2C) 1093 clk_prepare_enable(clks[MPC512x_CLK_I2C]); 1094 1095 FOR_NODES("fsl,mpc5121-diu") { 1096 NODE_PREP; 1097 NODE_CHK("ipg", clks[MPC512x_CLK_DIU], 1, DIU); 1098 } 1099 1100 FOR_NODES("fsl,mpc5121-viu") { 1101 NODE_PREP; 1102 NODE_CHK("ipg", clks[MPC512x_CLK_VIU], 0, VIU); 1103 } 1104 1105 /* 1106 * note that 2771399a "fs_enet: cleanup clock API use" did use the 1107 * "per" string for the clock lookup in contrast to the "ipg" name 1108 * which most other nodes are using -- this is not a fatal thing 1109 * but just something to keep in mind when doing compatibility 1110 * registration, it's a non-issue with up-to-date device tree data 1111 */ 1112 FOR_NODES("fsl,mpc5121-fec") { 1113 NODE_PREP; 1114 NODE_CHK("per", clks[MPC512x_CLK_FEC], 0, FEC); 1115 } 1116 FOR_NODES("fsl,mpc5121-fec-mdio") { 1117 NODE_PREP; 1118 NODE_CHK("per", clks[MPC512x_CLK_FEC], 0, FEC); 1119 } 1120 /* 1121 * MPC5125 has two FECs: FEC1 at 0x2800, FEC2 at 0x4800; 1122 * the clock items don't "form an array" since FEC2 was 1123 * added only later and was not allowed to shift all other 1124 * clock item indices, so the numbers aren't adjacent 1125 */ 1126 FOR_NODES("fsl,mpc5125-fec") { 1127 NODE_PREP; 1128 if (res.start & 0x4000) 1129 idx = MPC512x_CLK_FEC2; 1130 else 1131 idx = MPC512x_CLK_FEC; 1132 NODE_CHK("per", clks[idx], 0, FEC); 1133 } 1134 1135 FOR_NODES("fsl,mpc5121-usb2-dr") { 1136 NODE_PREP; 1137 idx = (res.start & 0x4000) ? 1 : 0; 1138 NODE_CHK("ipg", clks[MPC512x_CLK_USB1 + idx], 0, USB); 1139 } 1140 1141 FOR_NODES("fsl,mpc5121-pata") { 1142 NODE_PREP; 1143 NODE_CHK("ipg", clks[MPC512x_CLK_PATA], 0, PATA); 1144 } 1145 1146 /* 1147 * try to collapse diagnostics into a single line of output yet 1148 * provide a full list of what is missing, to avoid noise in the 1149 * absence of up-to-date device tree data -- backwards 1150 * compatibility to old DTBs is a requirement, updates may be 1151 * desirable or preferrable but are not at all mandatory 1152 */ 1153 if (did_register) { 1154 pr_notice("device tree lacks clock specs, adding fallbacks (0x%x,%s%s%s%s%s%s%s%s%s%s)\n", 1155 did_register, 1156 (did_register & DID_REG_PSC) ? " PSC" : "", 1157 (did_register & DID_REG_PSCFIFO) ? " PSCFIFO" : "", 1158 (did_register & DID_REG_NFC) ? " NFC" : "", 1159 (did_register & DID_REG_CAN) ? " CAN" : "", 1160 (did_register & DID_REG_I2C) ? " I2C" : "", 1161 (did_register & DID_REG_DIU) ? " DIU" : "", 1162 (did_register & DID_REG_VIU) ? " VIU" : "", 1163 (did_register & DID_REG_FEC) ? " FEC" : "", 1164 (did_register & DID_REG_USB) ? " USB" : "", 1165 (did_register & DID_REG_PATA) ? " PATA" : ""); 1166 } else { 1167 pr_debug("device tree has clock specs, no fallbacks added\n"); 1168 } 1169 } 1170 1171 int __init mpc5121_clk_init(void) 1172 { 1173 struct device_node *clk_np; 1174 int busfreq; 1175 1176 /* map the clock control registers */ 1177 clk_np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-clock"); 1178 if (!clk_np) 1179 return -ENODEV; 1180 clkregs = of_iomap(clk_np, 0); 1181 WARN_ON(!clkregs); 1182 1183 /* determine the SoC variant we run on */ 1184 mpc512x_clk_determine_soc(); 1185 1186 /* invalidate all not yet registered clock slots */ 1187 mpc512x_clk_preset_data(); 1188 1189 /* 1190 * have the device tree scanned for "fixed-clock" nodes (which 1191 * includes the oscillator node if the board's DT provides one) 1192 */ 1193 of_clk_init(NULL); 1194 1195 /* 1196 * add a dummy clock for those situations where a clock spec is 1197 * required yet no real clock is involved 1198 */ 1199 clks[MPC512x_CLK_DUMMY] = mpc512x_clk_fixed("dummy", 0); 1200 1201 /* 1202 * have all the real nodes in the clock tree populated from REF 1203 * down to all leaves, either starting from the OSC node or from 1204 * a REF root that was created from the IPS bus clock input 1205 */ 1206 busfreq = get_freq_from_dt("bus-frequency"); 1207 mpc512x_clk_setup_clock_tree(clk_np, busfreq); 1208 1209 /* register as an OF clock provider */ 1210 mpc5121_clk_register_of_provider(clk_np); 1211 1212 /* 1213 * unbreak not yet adjusted peripheral drivers during migration 1214 * towards fully operational common clock support, and allow 1215 * operation in the absence of clock related device tree specs 1216 */ 1217 mpc5121_clk_provide_migration_support(); 1218 mpc5121_clk_provide_backwards_compat(); 1219 1220 return 0; 1221 } 1222