1 /* 2 * linux/arch/arm/plat-mxc/time.c 3 * 4 * Copyright (C) 2000-2001 Deep Blue Solutions 5 * Copyright (C) 2002 Shane Nay (shane@minirl.com) 6 * Copyright (C) 2006-2007 Pavel Pisa (ppisa@pikron.com) 7 * Copyright (C) 2008 Juergen Beisert (kernel@pengutronix.de) 8 * 9 * This program is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU General Public License 11 * as published by the Free Software Foundation; either version 2 12 * of the License, or (at your option) any later version. 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, 21 * MA 02110-1301, USA. 22 */ 23 24 #include <linux/interrupt.h> 25 #include <linux/irq.h> 26 #include <linux/clockchips.h> 27 #include <linux/clk.h> 28 #include <linux/delay.h> 29 #include <linux/err.h> 30 #include <linux/sched_clock.h> 31 #include <linux/slab.h> 32 #include <linux/of.h> 33 #include <linux/of_address.h> 34 #include <linux/of_irq.h> 35 #include <soc/imx/timer.h> 36 37 /* 38 * There are 4 versions of the timer hardware on Freescale MXC hardware. 39 * - MX1/MXL 40 * - MX21, MX27. 41 * - MX25, MX31, MX35, MX37, MX51, MX6Q(rev1.0) 42 * - MX6DL, MX6SX, MX6Q(rev1.1+) 43 */ 44 45 /* defines common for all i.MX */ 46 #define MXC_TCTL 0x00 47 #define MXC_TCTL_TEN (1 << 0) /* Enable module */ 48 #define MXC_TPRER 0x04 49 50 /* MX1, MX21, MX27 */ 51 #define MX1_2_TCTL_CLK_PCLK1 (1 << 1) 52 #define MX1_2_TCTL_IRQEN (1 << 4) 53 #define MX1_2_TCTL_FRR (1 << 8) 54 #define MX1_2_TCMP 0x08 55 #define MX1_2_TCN 0x10 56 #define MX1_2_TSTAT 0x14 57 58 /* MX21, MX27 */ 59 #define MX2_TSTAT_CAPT (1 << 1) 60 #define MX2_TSTAT_COMP (1 << 0) 61 62 /* MX31, MX35, MX25, MX5, MX6 */ 63 #define V2_TCTL_WAITEN (1 << 3) /* Wait enable mode */ 64 #define V2_TCTL_CLK_IPG (1 << 6) 65 #define V2_TCTL_CLK_PER (2 << 6) 66 #define V2_TCTL_CLK_OSC_DIV8 (5 << 6) 67 #define V2_TCTL_FRR (1 << 9) 68 #define V2_TCTL_24MEN (1 << 10) 69 #define V2_TPRER_PRE24M 12 70 #define V2_IR 0x0c 71 #define V2_TSTAT 0x08 72 #define V2_TSTAT_OF1 (1 << 0) 73 #define V2_TCN 0x24 74 #define V2_TCMP 0x10 75 76 #define V2_TIMER_RATE_OSC_DIV8 3000000 77 78 struct imx_timer { 79 enum imx_gpt_type type; 80 void __iomem *base; 81 int irq; 82 struct clk *clk_per; 83 struct clk *clk_ipg; 84 const struct imx_gpt_data *gpt; 85 struct clock_event_device ced; 86 struct irqaction act; 87 }; 88 89 struct imx_gpt_data { 90 int reg_tstat; 91 int reg_tcn; 92 int reg_tcmp; 93 void (*gpt_setup_tctl)(struct imx_timer *imxtm); 94 void (*gpt_irq_enable)(struct imx_timer *imxtm); 95 void (*gpt_irq_disable)(struct imx_timer *imxtm); 96 void (*gpt_irq_acknowledge)(struct imx_timer *imxtm); 97 int (*set_next_event)(unsigned long evt, 98 struct clock_event_device *ced); 99 }; 100 101 static inline struct imx_timer *to_imx_timer(struct clock_event_device *ced) 102 { 103 return container_of(ced, struct imx_timer, ced); 104 } 105 106 static void imx1_gpt_irq_disable(struct imx_timer *imxtm) 107 { 108 unsigned int tmp; 109 110 tmp = readl_relaxed(imxtm->base + MXC_TCTL); 111 writel_relaxed(tmp & ~MX1_2_TCTL_IRQEN, imxtm->base + MXC_TCTL); 112 } 113 #define imx21_gpt_irq_disable imx1_gpt_irq_disable 114 115 static void imx31_gpt_irq_disable(struct imx_timer *imxtm) 116 { 117 writel_relaxed(0, imxtm->base + V2_IR); 118 } 119 #define imx6dl_gpt_irq_disable imx31_gpt_irq_disable 120 121 static void imx1_gpt_irq_enable(struct imx_timer *imxtm) 122 { 123 unsigned int tmp; 124 125 tmp = readl_relaxed(imxtm->base + MXC_TCTL); 126 writel_relaxed(tmp | MX1_2_TCTL_IRQEN, imxtm->base + MXC_TCTL); 127 } 128 #define imx21_gpt_irq_enable imx1_gpt_irq_enable 129 130 static void imx31_gpt_irq_enable(struct imx_timer *imxtm) 131 { 132 writel_relaxed(1<<0, imxtm->base + V2_IR); 133 } 134 #define imx6dl_gpt_irq_enable imx31_gpt_irq_enable 135 136 static void imx1_gpt_irq_acknowledge(struct imx_timer *imxtm) 137 { 138 writel_relaxed(0, imxtm->base + MX1_2_TSTAT); 139 } 140 141 static void imx21_gpt_irq_acknowledge(struct imx_timer *imxtm) 142 { 143 writel_relaxed(MX2_TSTAT_CAPT | MX2_TSTAT_COMP, 144 imxtm->base + MX1_2_TSTAT); 145 } 146 147 static void imx31_gpt_irq_acknowledge(struct imx_timer *imxtm) 148 { 149 writel_relaxed(V2_TSTAT_OF1, imxtm->base + V2_TSTAT); 150 } 151 #define imx6dl_gpt_irq_acknowledge imx31_gpt_irq_acknowledge 152 153 static void __iomem *sched_clock_reg; 154 155 static u64 notrace mxc_read_sched_clock(void) 156 { 157 return sched_clock_reg ? readl_relaxed(sched_clock_reg) : 0; 158 } 159 160 static struct delay_timer imx_delay_timer; 161 162 static unsigned long imx_read_current_timer(void) 163 { 164 return readl_relaxed(sched_clock_reg); 165 } 166 167 static int __init mxc_clocksource_init(struct imx_timer *imxtm) 168 { 169 unsigned int c = clk_get_rate(imxtm->clk_per); 170 void __iomem *reg = imxtm->base + imxtm->gpt->reg_tcn; 171 172 imx_delay_timer.read_current_timer = &imx_read_current_timer; 173 imx_delay_timer.freq = c; 174 register_current_timer_delay(&imx_delay_timer); 175 176 sched_clock_reg = reg; 177 178 sched_clock_register(mxc_read_sched_clock, 32, c); 179 return clocksource_mmio_init(reg, "mxc_timer1", c, 200, 32, 180 clocksource_mmio_readl_up); 181 } 182 183 /* clock event */ 184 185 static int mx1_2_set_next_event(unsigned long evt, 186 struct clock_event_device *ced) 187 { 188 struct imx_timer *imxtm = to_imx_timer(ced); 189 unsigned long tcmp; 190 191 tcmp = readl_relaxed(imxtm->base + MX1_2_TCN) + evt; 192 193 writel_relaxed(tcmp, imxtm->base + MX1_2_TCMP); 194 195 return (int)(tcmp - readl_relaxed(imxtm->base + MX1_2_TCN)) < 0 ? 196 -ETIME : 0; 197 } 198 199 static int v2_set_next_event(unsigned long evt, 200 struct clock_event_device *ced) 201 { 202 struct imx_timer *imxtm = to_imx_timer(ced); 203 unsigned long tcmp; 204 205 tcmp = readl_relaxed(imxtm->base + V2_TCN) + evt; 206 207 writel_relaxed(tcmp, imxtm->base + V2_TCMP); 208 209 return evt < 0x7fffffff && 210 (int)(tcmp - readl_relaxed(imxtm->base + V2_TCN)) < 0 ? 211 -ETIME : 0; 212 } 213 214 static int mxc_shutdown(struct clock_event_device *ced) 215 { 216 struct imx_timer *imxtm = to_imx_timer(ced); 217 unsigned long flags; 218 u32 tcn; 219 220 /* 221 * The timer interrupt generation is disabled at least 222 * for enough time to call mxc_set_next_event() 223 */ 224 local_irq_save(flags); 225 226 /* Disable interrupt in GPT module */ 227 imxtm->gpt->gpt_irq_disable(imxtm); 228 229 tcn = readl_relaxed(imxtm->base + imxtm->gpt->reg_tcn); 230 /* Set event time into far-far future */ 231 writel_relaxed(tcn - 3, imxtm->base + imxtm->gpt->reg_tcmp); 232 233 /* Clear pending interrupt */ 234 imxtm->gpt->gpt_irq_acknowledge(imxtm); 235 236 #ifdef DEBUG 237 printk(KERN_INFO "%s: changing mode\n", __func__); 238 #endif /* DEBUG */ 239 240 local_irq_restore(flags); 241 242 return 0; 243 } 244 245 static int mxc_set_oneshot(struct clock_event_device *ced) 246 { 247 struct imx_timer *imxtm = to_imx_timer(ced); 248 unsigned long flags; 249 250 /* 251 * The timer interrupt generation is disabled at least 252 * for enough time to call mxc_set_next_event() 253 */ 254 local_irq_save(flags); 255 256 /* Disable interrupt in GPT module */ 257 imxtm->gpt->gpt_irq_disable(imxtm); 258 259 if (!clockevent_state_oneshot(ced)) { 260 u32 tcn = readl_relaxed(imxtm->base + imxtm->gpt->reg_tcn); 261 /* Set event time into far-far future */ 262 writel_relaxed(tcn - 3, imxtm->base + imxtm->gpt->reg_tcmp); 263 264 /* Clear pending interrupt */ 265 imxtm->gpt->gpt_irq_acknowledge(imxtm); 266 } 267 268 #ifdef DEBUG 269 printk(KERN_INFO "%s: changing mode\n", __func__); 270 #endif /* DEBUG */ 271 272 /* 273 * Do not put overhead of interrupt enable/disable into 274 * mxc_set_next_event(), the core has about 4 minutes 275 * to call mxc_set_next_event() or shutdown clock after 276 * mode switching 277 */ 278 imxtm->gpt->gpt_irq_enable(imxtm); 279 local_irq_restore(flags); 280 281 return 0; 282 } 283 284 /* 285 * IRQ handler for the timer 286 */ 287 static irqreturn_t mxc_timer_interrupt(int irq, void *dev_id) 288 { 289 struct clock_event_device *ced = dev_id; 290 struct imx_timer *imxtm = to_imx_timer(ced); 291 uint32_t tstat; 292 293 tstat = readl_relaxed(imxtm->base + imxtm->gpt->reg_tstat); 294 295 imxtm->gpt->gpt_irq_acknowledge(imxtm); 296 297 ced->event_handler(ced); 298 299 return IRQ_HANDLED; 300 } 301 302 static int __init mxc_clockevent_init(struct imx_timer *imxtm) 303 { 304 struct clock_event_device *ced = &imxtm->ced; 305 struct irqaction *act = &imxtm->act; 306 307 ced->name = "mxc_timer1"; 308 ced->features = CLOCK_EVT_FEAT_ONESHOT; 309 ced->set_state_shutdown = mxc_shutdown; 310 ced->set_state_oneshot = mxc_set_oneshot; 311 ced->tick_resume = mxc_shutdown; 312 ced->set_next_event = imxtm->gpt->set_next_event; 313 ced->rating = 200; 314 ced->cpumask = cpumask_of(0); 315 clockevents_config_and_register(ced, clk_get_rate(imxtm->clk_per), 316 0xff, 0xfffffffe); 317 318 act->name = "i.MX Timer Tick"; 319 act->flags = IRQF_TIMER | IRQF_IRQPOLL; 320 act->handler = mxc_timer_interrupt; 321 act->dev_id = ced; 322 323 return setup_irq(imxtm->irq, act); 324 } 325 326 static void imx1_gpt_setup_tctl(struct imx_timer *imxtm) 327 { 328 u32 tctl_val; 329 330 tctl_val = MX1_2_TCTL_FRR | MX1_2_TCTL_CLK_PCLK1 | MXC_TCTL_TEN; 331 writel_relaxed(tctl_val, imxtm->base + MXC_TCTL); 332 } 333 #define imx21_gpt_setup_tctl imx1_gpt_setup_tctl 334 335 static void imx31_gpt_setup_tctl(struct imx_timer *imxtm) 336 { 337 u32 tctl_val; 338 339 tctl_val = V2_TCTL_FRR | V2_TCTL_WAITEN | MXC_TCTL_TEN; 340 if (clk_get_rate(imxtm->clk_per) == V2_TIMER_RATE_OSC_DIV8) 341 tctl_val |= V2_TCTL_CLK_OSC_DIV8; 342 else 343 tctl_val |= V2_TCTL_CLK_PER; 344 345 writel_relaxed(tctl_val, imxtm->base + MXC_TCTL); 346 } 347 348 static void imx6dl_gpt_setup_tctl(struct imx_timer *imxtm) 349 { 350 u32 tctl_val; 351 352 tctl_val = V2_TCTL_FRR | V2_TCTL_WAITEN | MXC_TCTL_TEN; 353 if (clk_get_rate(imxtm->clk_per) == V2_TIMER_RATE_OSC_DIV8) { 354 tctl_val |= V2_TCTL_CLK_OSC_DIV8; 355 /* 24 / 8 = 3 MHz */ 356 writel_relaxed(7 << V2_TPRER_PRE24M, imxtm->base + MXC_TPRER); 357 tctl_val |= V2_TCTL_24MEN; 358 } else { 359 tctl_val |= V2_TCTL_CLK_PER; 360 } 361 362 writel_relaxed(tctl_val, imxtm->base + MXC_TCTL); 363 } 364 365 static const struct imx_gpt_data imx1_gpt_data = { 366 .reg_tstat = MX1_2_TSTAT, 367 .reg_tcn = MX1_2_TCN, 368 .reg_tcmp = MX1_2_TCMP, 369 .gpt_irq_enable = imx1_gpt_irq_enable, 370 .gpt_irq_disable = imx1_gpt_irq_disable, 371 .gpt_irq_acknowledge = imx1_gpt_irq_acknowledge, 372 .gpt_setup_tctl = imx1_gpt_setup_tctl, 373 .set_next_event = mx1_2_set_next_event, 374 }; 375 376 static const struct imx_gpt_data imx21_gpt_data = { 377 .reg_tstat = MX1_2_TSTAT, 378 .reg_tcn = MX1_2_TCN, 379 .reg_tcmp = MX1_2_TCMP, 380 .gpt_irq_enable = imx21_gpt_irq_enable, 381 .gpt_irq_disable = imx21_gpt_irq_disable, 382 .gpt_irq_acknowledge = imx21_gpt_irq_acknowledge, 383 .gpt_setup_tctl = imx21_gpt_setup_tctl, 384 .set_next_event = mx1_2_set_next_event, 385 }; 386 387 static const struct imx_gpt_data imx31_gpt_data = { 388 .reg_tstat = V2_TSTAT, 389 .reg_tcn = V2_TCN, 390 .reg_tcmp = V2_TCMP, 391 .gpt_irq_enable = imx31_gpt_irq_enable, 392 .gpt_irq_disable = imx31_gpt_irq_disable, 393 .gpt_irq_acknowledge = imx31_gpt_irq_acknowledge, 394 .gpt_setup_tctl = imx31_gpt_setup_tctl, 395 .set_next_event = v2_set_next_event, 396 }; 397 398 static const struct imx_gpt_data imx6dl_gpt_data = { 399 .reg_tstat = V2_TSTAT, 400 .reg_tcn = V2_TCN, 401 .reg_tcmp = V2_TCMP, 402 .gpt_irq_enable = imx6dl_gpt_irq_enable, 403 .gpt_irq_disable = imx6dl_gpt_irq_disable, 404 .gpt_irq_acknowledge = imx6dl_gpt_irq_acknowledge, 405 .gpt_setup_tctl = imx6dl_gpt_setup_tctl, 406 .set_next_event = v2_set_next_event, 407 }; 408 409 static void __init _mxc_timer_init(struct imx_timer *imxtm) 410 { 411 switch (imxtm->type) { 412 case GPT_TYPE_IMX1: 413 imxtm->gpt = &imx1_gpt_data; 414 break; 415 case GPT_TYPE_IMX21: 416 imxtm->gpt = &imx21_gpt_data; 417 break; 418 case GPT_TYPE_IMX31: 419 imxtm->gpt = &imx31_gpt_data; 420 break; 421 case GPT_TYPE_IMX6DL: 422 imxtm->gpt = &imx6dl_gpt_data; 423 break; 424 default: 425 BUG(); 426 } 427 428 if (IS_ERR(imxtm->clk_per)) { 429 pr_err("i.MX timer: unable to get clk\n"); 430 return; 431 } 432 433 if (!IS_ERR(imxtm->clk_ipg)) 434 clk_prepare_enable(imxtm->clk_ipg); 435 436 clk_prepare_enable(imxtm->clk_per); 437 438 /* 439 * Initialise to a known state (all timers off, and timing reset) 440 */ 441 442 writel_relaxed(0, imxtm->base + MXC_TCTL); 443 writel_relaxed(0, imxtm->base + MXC_TPRER); /* see datasheet note */ 444 445 imxtm->gpt->gpt_setup_tctl(imxtm); 446 447 /* init and register the timer to the framework */ 448 mxc_clocksource_init(imxtm); 449 mxc_clockevent_init(imxtm); 450 } 451 452 void __init mxc_timer_init(unsigned long pbase, int irq, enum imx_gpt_type type) 453 { 454 struct imx_timer *imxtm; 455 456 imxtm = kzalloc(sizeof(*imxtm), GFP_KERNEL); 457 BUG_ON(!imxtm); 458 459 imxtm->clk_per = clk_get_sys("imx-gpt.0", "per"); 460 imxtm->clk_ipg = clk_get_sys("imx-gpt.0", "ipg"); 461 462 imxtm->base = ioremap(pbase, SZ_4K); 463 BUG_ON(!imxtm->base); 464 465 imxtm->type = type; 466 467 _mxc_timer_init(imxtm); 468 } 469 470 static void __init mxc_timer_init_dt(struct device_node *np, enum imx_gpt_type type) 471 { 472 struct imx_timer *imxtm; 473 static int initialized; 474 475 /* Support one instance only */ 476 if (initialized) 477 return; 478 479 imxtm = kzalloc(sizeof(*imxtm), GFP_KERNEL); 480 BUG_ON(!imxtm); 481 482 imxtm->base = of_iomap(np, 0); 483 WARN_ON(!imxtm->base); 484 imxtm->irq = irq_of_parse_and_map(np, 0); 485 486 imxtm->clk_ipg = of_clk_get_by_name(np, "ipg"); 487 488 /* Try osc_per first, and fall back to per otherwise */ 489 imxtm->clk_per = of_clk_get_by_name(np, "osc_per"); 490 if (IS_ERR(imxtm->clk_per)) 491 imxtm->clk_per = of_clk_get_by_name(np, "per"); 492 493 imxtm->type = type; 494 495 _mxc_timer_init(imxtm); 496 497 initialized = 1; 498 } 499 500 static void __init imx1_timer_init_dt(struct device_node *np) 501 { 502 mxc_timer_init_dt(np, GPT_TYPE_IMX1); 503 } 504 505 static void __init imx21_timer_init_dt(struct device_node *np) 506 { 507 mxc_timer_init_dt(np, GPT_TYPE_IMX21); 508 } 509 510 static void __init imx31_timer_init_dt(struct device_node *np) 511 { 512 enum imx_gpt_type type = GPT_TYPE_IMX31; 513 514 /* 515 * We were using the same compatible string for i.MX6Q/D and i.MX6DL/S 516 * GPT device, while they actually have different programming model. 517 * This is a workaround to keep the existing i.MX6DL/S DTBs continue 518 * working with the new kernel. 519 */ 520 if (of_machine_is_compatible("fsl,imx6dl")) 521 type = GPT_TYPE_IMX6DL; 522 523 mxc_timer_init_dt(np, type); 524 } 525 526 static void __init imx6dl_timer_init_dt(struct device_node *np) 527 { 528 mxc_timer_init_dt(np, GPT_TYPE_IMX6DL); 529 } 530 531 CLOCKSOURCE_OF_DECLARE(imx1_timer, "fsl,imx1-gpt", imx1_timer_init_dt); 532 CLOCKSOURCE_OF_DECLARE(imx21_timer, "fsl,imx21-gpt", imx21_timer_init_dt); 533 CLOCKSOURCE_OF_DECLARE(imx27_timer, "fsl,imx27-gpt", imx21_timer_init_dt); 534 CLOCKSOURCE_OF_DECLARE(imx31_timer, "fsl,imx31-gpt", imx31_timer_init_dt); 535 CLOCKSOURCE_OF_DECLARE(imx25_timer, "fsl,imx25-gpt", imx31_timer_init_dt); 536 CLOCKSOURCE_OF_DECLARE(imx50_timer, "fsl,imx50-gpt", imx31_timer_init_dt); 537 CLOCKSOURCE_OF_DECLARE(imx51_timer, "fsl,imx51-gpt", imx31_timer_init_dt); 538 CLOCKSOURCE_OF_DECLARE(imx53_timer, "fsl,imx53-gpt", imx31_timer_init_dt); 539 CLOCKSOURCE_OF_DECLARE(imx6q_timer, "fsl,imx6q-gpt", imx31_timer_init_dt); 540 CLOCKSOURCE_OF_DECLARE(imx6dl_timer, "fsl,imx6dl-gpt", imx6dl_timer_init_dt); 541 CLOCKSOURCE_OF_DECLARE(imx6sl_timer, "fsl,imx6sl-gpt", imx6dl_timer_init_dt); 542 CLOCKSOURCE_OF_DECLARE(imx6sx_timer, "fsl,imx6sx-gpt", imx6dl_timer_init_dt); 543