| 1 | // SPDX-License-Identifier: GPL-2.0-only |
| 2 | /* |
| 3 | * linux/drivers/clocksource/arm_arch_timer.c |
| 4 | * |
| 5 | * Copyright (C) 2011 ARM Ltd. |
| 6 | * All Rights Reserved |
| 7 | */ |
| 8 | |
| 9 | #define pr_fmt(fmt) "arch_timer: " fmt |
| 10 | |
| 11 | #include <linux/init.h> |
| 12 | #include <linux/kernel.h> |
| 13 | #include <linux/device.h> |
| 14 | #include <linux/smp.h> |
| 15 | #include <linux/cpu.h> |
| 16 | #include <linux/cpu_pm.h> |
| 17 | #include <linux/clockchips.h> |
| 18 | #include <linux/clocksource.h> |
| 19 | #include <linux/interrupt.h> |
| 20 | #include <linux/of_irq.h> |
| 21 | #include <linux/of_address.h> |
| 22 | #include <linux/io.h> |
| 23 | #include <linux/slab.h> |
| 24 | #include <linux/sched/clock.h> |
| 25 | #include <linux/sched_clock.h> |
| 26 | #include <linux/acpi.h> |
| 27 | |
| 28 | #include <asm/arch_timer.h> |
| 29 | #include <asm/virt.h> |
| 30 | |
| 31 | #include <clocksource/arm_arch_timer.h> |
| 32 | |
| 33 | #define CNTTIDR 0x08 |
| 34 | #define CNTTIDR_VIRT(n) (BIT(1) << ((n) * 4)) |
| 35 | |
| 36 | #define CNTACR(n) (0x40 + ((n) * 4)) |
| 37 | #define CNTACR_RPCT BIT(0) |
| 38 | #define CNTACR_RVCT BIT(1) |
| 39 | #define CNTACR_RFRQ BIT(2) |
| 40 | #define CNTACR_RVOFF BIT(3) |
| 41 | #define CNTACR_RWVT BIT(4) |
| 42 | #define CNTACR_RWPT BIT(5) |
| 43 | |
| 44 | #define CNTVCT_LO 0x08 |
| 45 | #define CNTVCT_HI 0x0c |
| 46 | #define CNTFRQ 0x10 |
| 47 | #define CNTP_TVAL 0x28 |
| 48 | #define CNTP_CTL 0x2c |
| 49 | #define CNTV_TVAL 0x38 |
| 50 | #define CNTV_CTL 0x3c |
| 51 | |
| 52 | static unsigned arch_timers_present __initdata; |
| 53 | |
| 54 | static void __iomem *arch_counter_base; |
| 55 | |
| 56 | struct arch_timer { |
| 57 | void __iomem *base; |
| 58 | struct clock_event_device evt; |
| 59 | }; |
| 60 | |
| 61 | #define to_arch_timer(e) container_of(e, struct arch_timer, evt) |
| 62 | |
| 63 | static u32 arch_timer_rate; |
| 64 | static int arch_timer_ppi[ARCH_TIMER_MAX_TIMER_PPI]; |
| 65 | |
| 66 | static struct clock_event_device __percpu *arch_timer_evt; |
| 67 | |
| 68 | static enum arch_timer_ppi_nr arch_timer_uses_ppi = ARCH_TIMER_VIRT_PPI; |
| 69 | static bool arch_timer_c3stop; |
| 70 | static bool arch_timer_mem_use_virtual; |
| 71 | static bool arch_counter_suspend_stop; |
| 72 | #ifdef CONFIG_GENERIC_GETTIMEOFDAY |
| 73 | static enum vdso_clock_mode vdso_default = VDSO_CLOCKMODE_ARCHTIMER; |
| 74 | #else |
| 75 | static enum vdso_clock_mode vdso_default = VDSO_CLOCKMODE_NONE; |
| 76 | #endif /* CONFIG_GENERIC_GETTIMEOFDAY */ |
| 77 | |
| 78 | static cpumask_t evtstrm_available = CPU_MASK_NONE; |
| 79 | static bool evtstrm_enable = IS_ENABLED(CONFIG_ARM_ARCH_TIMER_EVTSTREAM); |
| 80 | |
| 81 | static int __init early_evtstrm_cfg(char *buf) |
| 82 | { |
| 83 | return strtobool(buf, &evtstrm_enable); |
| 84 | } |
| 85 | early_param("clocksource.arm_arch_timer.evtstrm", early_evtstrm_cfg); |
| 86 | |
| 87 | /* |
| 88 | * Architected system timer support. |
| 89 | */ |
| 90 | |
| 91 | static __always_inline |
| 92 | void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val, |
| 93 | struct clock_event_device *clk) |
| 94 | { |
| 95 | if (access == ARCH_TIMER_MEM_PHYS_ACCESS) { |
| 96 | struct arch_timer *timer = to_arch_timer(clk); |
| 97 | switch (reg) { |
| 98 | case ARCH_TIMER_REG_CTRL: |
| 99 | writel_relaxed(val, timer->base + CNTP_CTL); |
| 100 | break; |
| 101 | case ARCH_TIMER_REG_TVAL: |
| 102 | writel_relaxed(val, timer->base + CNTP_TVAL); |
| 103 | break; |
| 104 | } |
| 105 | } else if (access == ARCH_TIMER_MEM_VIRT_ACCESS) { |
| 106 | struct arch_timer *timer = to_arch_timer(clk); |
| 107 | switch (reg) { |
| 108 | case ARCH_TIMER_REG_CTRL: |
| 109 | writel_relaxed(val, timer->base + CNTV_CTL); |
| 110 | break; |
| 111 | case ARCH_TIMER_REG_TVAL: |
| 112 | writel_relaxed(val, timer->base + CNTV_TVAL); |
| 113 | break; |
| 114 | } |
| 115 | } else { |
| 116 | arch_timer_reg_write_cp15(access, reg, val); |
| 117 | } |
| 118 | } |
| 119 | |
| 120 | static __always_inline |
| 121 | u32 arch_timer_reg_read(int access, enum arch_timer_reg reg, |
| 122 | struct clock_event_device *clk) |
| 123 | { |
| 124 | u32 val; |
| 125 | |
| 126 | if (access == ARCH_TIMER_MEM_PHYS_ACCESS) { |
| 127 | struct arch_timer *timer = to_arch_timer(clk); |
| 128 | switch (reg) { |
| 129 | case ARCH_TIMER_REG_CTRL: |
| 130 | val = readl_relaxed(timer->base + CNTP_CTL); |
| 131 | break; |
| 132 | case ARCH_TIMER_REG_TVAL: |
| 133 | val = readl_relaxed(timer->base + CNTP_TVAL); |
| 134 | break; |
| 135 | } |
| 136 | } else if (access == ARCH_TIMER_MEM_VIRT_ACCESS) { |
| 137 | struct arch_timer *timer = to_arch_timer(clk); |
| 138 | switch (reg) { |
| 139 | case ARCH_TIMER_REG_CTRL: |
| 140 | val = readl_relaxed(timer->base + CNTV_CTL); |
| 141 | break; |
| 142 | case ARCH_TIMER_REG_TVAL: |
| 143 | val = readl_relaxed(timer->base + CNTV_TVAL); |
| 144 | break; |
| 145 | } |
| 146 | } else { |
| 147 | val = arch_timer_reg_read_cp15(access, reg); |
| 148 | } |
| 149 | |
| 150 | return val; |
| 151 | } |
| 152 | |
| 153 | static notrace u64 arch_counter_get_cntpct_stable(void) |
| 154 | { |
| 155 | return __arch_counter_get_cntpct_stable(); |
| 156 | } |
| 157 | |
| 158 | static notrace u64 arch_counter_get_cntpct(void) |
| 159 | { |
| 160 | return __arch_counter_get_cntpct(); |
| 161 | } |
| 162 | |
| 163 | static notrace u64 arch_counter_get_cntvct_stable(void) |
| 164 | { |
| 165 | return __arch_counter_get_cntvct_stable(); |
| 166 | } |
| 167 | |
| 168 | static notrace u64 arch_counter_get_cntvct(void) |
| 169 | { |
| 170 | return __arch_counter_get_cntvct(); |
| 171 | } |
| 172 | |
| 173 | /* |
| 174 | * Default to cp15 based access because arm64 uses this function for |
| 175 | * sched_clock() before DT is probed and the cp15 method is guaranteed |
| 176 | * to exist on arm64. arm doesn't use this before DT is probed so even |
| 177 | * if we don't have the cp15 accessors we won't have a problem. |
| 178 | */ |
| 179 | u64 (*arch_timer_read_counter)(void) = arch_counter_get_cntvct; |
| 180 | EXPORT_SYMBOL_GPL(arch_timer_read_counter); |
| 181 | |
| 182 | static u64 arch_counter_read(struct clocksource *cs) |
| 183 | { |
| 184 | return arch_timer_read_counter(); |
| 185 | } |
| 186 | |
| 187 | static u64 arch_counter_read_cc(const struct cyclecounter *cc) |
| 188 | { |
| 189 | return arch_timer_read_counter(); |
| 190 | } |
| 191 | |
| 192 | static struct clocksource clocksource_counter = { |
| 193 | .name = "arch_sys_counter", |
| 194 | .rating = 400, |
| 195 | .read = arch_counter_read, |
| 196 | .mask = CLOCKSOURCE_MASK(56), |
| 197 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, |
| 198 | }; |
| 199 | |
| 200 | static struct cyclecounter cyclecounter __ro_after_init = { |
| 201 | .read = arch_counter_read_cc, |
| 202 | .mask = CLOCKSOURCE_MASK(56), |
| 203 | }; |
| 204 | |
| 205 | struct ate_acpi_oem_info { |
| 206 | char oem_id[ACPI_OEM_ID_SIZE + 1]; |
| 207 | char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1]; |
| 208 | u32 oem_revision; |
| 209 | }; |
| 210 | |
| 211 | #ifdef CONFIG_FSL_ERRATUM_A008585 |
| 212 | /* |
| 213 | * The number of retries is an arbitrary value well beyond the highest number |
| 214 | * of iterations the loop has been observed to take. |
| 215 | */ |
| 216 | #define __fsl_a008585_read_reg(reg) ({ \ |
| 217 | u64 _old, _new; \ |
| 218 | int _retries = 200; \ |
| 219 | \ |
| 220 | do { \ |
| 221 | _old = read_sysreg(reg); \ |
| 222 | _new = read_sysreg(reg); \ |
| 223 | _retries--; \ |
| 224 | } while (unlikely(_old != _new) && _retries); \ |
| 225 | \ |
| 226 | WARN_ON_ONCE(!_retries); \ |
| 227 | _new; \ |
| 228 | }) |
| 229 | |
| 230 | static u32 notrace fsl_a008585_read_cntp_tval_el0(void) |
| 231 | { |
| 232 | return __fsl_a008585_read_reg(cntp_tval_el0); |
| 233 | } |
| 234 | |
| 235 | static u32 notrace fsl_a008585_read_cntv_tval_el0(void) |
| 236 | { |
| 237 | return __fsl_a008585_read_reg(cntv_tval_el0); |
| 238 | } |
| 239 | |
| 240 | static u64 notrace fsl_a008585_read_cntpct_el0(void) |
| 241 | { |
| 242 | return __fsl_a008585_read_reg(cntpct_el0); |
| 243 | } |
| 244 | |
| 245 | static u64 notrace fsl_a008585_read_cntvct_el0(void) |
| 246 | { |
| 247 | return __fsl_a008585_read_reg(cntvct_el0); |
| 248 | } |
| 249 | #endif |
| 250 | |
| 251 | #ifdef CONFIG_HISILICON_ERRATUM_161010101 |
| 252 | /* |
| 253 | * Verify whether the value of the second read is larger than the first by |
| 254 | * less than 32 is the only way to confirm the value is correct, so clear the |
| 255 | * lower 5 bits to check whether the difference is greater than 32 or not. |
| 256 | * Theoretically the erratum should not occur more than twice in succession |
| 257 | * when reading the system counter, but it is possible that some interrupts |
| 258 | * may lead to more than twice read errors, triggering the warning, so setting |
| 259 | * the number of retries far beyond the number of iterations the loop has been |
| 260 | * observed to take. |
| 261 | */ |
| 262 | #define __hisi_161010101_read_reg(reg) ({ \ |
| 263 | u64 _old, _new; \ |
| 264 | int _retries = 50; \ |
| 265 | \ |
| 266 | do { \ |
| 267 | _old = read_sysreg(reg); \ |
| 268 | _new = read_sysreg(reg); \ |
| 269 | _retries--; \ |
| 270 | } while (unlikely((_new - _old) >> 5) && _retries); \ |
| 271 | \ |
| 272 | WARN_ON_ONCE(!_retries); \ |
| 273 | _new; \ |
| 274 | }) |
| 275 | |
| 276 | static u32 notrace hisi_161010101_read_cntp_tval_el0(void) |
| 277 | { |
| 278 | return __hisi_161010101_read_reg(cntp_tval_el0); |
| 279 | } |
| 280 | |
| 281 | static u32 notrace hisi_161010101_read_cntv_tval_el0(void) |
| 282 | { |
| 283 | return __hisi_161010101_read_reg(cntv_tval_el0); |
| 284 | } |
| 285 | |
| 286 | static u64 notrace hisi_161010101_read_cntpct_el0(void) |
| 287 | { |
| 288 | return __hisi_161010101_read_reg(cntpct_el0); |
| 289 | } |
| 290 | |
| 291 | static u64 notrace hisi_161010101_read_cntvct_el0(void) |
| 292 | { |
| 293 | return __hisi_161010101_read_reg(cntvct_el0); |
| 294 | } |
| 295 | |
| 296 | static struct ate_acpi_oem_info hisi_161010101_oem_info[] = { |
| 297 | /* |
| 298 | * Note that trailing spaces are required to properly match |
| 299 | * the OEM table information. |
| 300 | */ |
| 301 | { |
| 302 | .oem_id = "HISI ", |
| 303 | .oem_table_id = "HIP05 ", |
| 304 | .oem_revision = 0, |
| 305 | }, |
| 306 | { |
| 307 | .oem_id = "HISI ", |
| 308 | .oem_table_id = "HIP06 ", |
| 309 | .oem_revision = 0, |
| 310 | }, |
| 311 | { |
| 312 | .oem_id = "HISI ", |
| 313 | .oem_table_id = "HIP07 ", |
| 314 | .oem_revision = 0, |
| 315 | }, |
| 316 | { /* Sentinel indicating the end of the OEM array */ }, |
| 317 | }; |
| 318 | #endif |
| 319 | |
| 320 | #ifdef CONFIG_ARM64_ERRATUM_858921 |
| 321 | static u64 notrace arm64_858921_read_cntpct_el0(void) |
| 322 | { |
| 323 | u64 old, new; |
| 324 | |
| 325 | old = read_sysreg(cntpct_el0); |
| 326 | new = read_sysreg(cntpct_el0); |
| 327 | return (((old ^ new) >> 32) & 1) ? old : new; |
| 328 | } |
| 329 | |
| 330 | static u64 notrace arm64_858921_read_cntvct_el0(void) |
| 331 | { |
| 332 | u64 old, new; |
| 333 | |
| 334 | old = read_sysreg(cntvct_el0); |
| 335 | new = read_sysreg(cntvct_el0); |
| 336 | return (((old ^ new) >> 32) & 1) ? old : new; |
| 337 | } |
| 338 | #endif |
| 339 | |
| 340 | #ifdef CONFIG_SUN50I_ERRATUM_UNKNOWN1 |
| 341 | /* |
| 342 | * The low bits of the counter registers are indeterminate while bit 10 or |
| 343 | * greater is rolling over. Since the counter value can jump both backward |
| 344 | * (7ff -> 000 -> 800) and forward (7ff -> fff -> 800), ignore register values |
| 345 | * with all ones or all zeros in the low bits. Bound the loop by the maximum |
| 346 | * number of CPU cycles in 3 consecutive 24 MHz counter periods. |
| 347 | */ |
| 348 | #define __sun50i_a64_read_reg(reg) ({ \ |
| 349 | u64 _val; \ |
| 350 | int _retries = 150; \ |
| 351 | \ |
| 352 | do { \ |
| 353 | _val = read_sysreg(reg); \ |
| 354 | _retries--; \ |
| 355 | } while (((_val + 1) & GENMASK(9, 0)) <= 1 && _retries); \ |
| 356 | \ |
| 357 | WARN_ON_ONCE(!_retries); \ |
| 358 | _val; \ |
| 359 | }) |
| 360 | |
| 361 | static u64 notrace sun50i_a64_read_cntpct_el0(void) |
| 362 | { |
| 363 | return __sun50i_a64_read_reg(cntpct_el0); |
| 364 | } |
| 365 | |
| 366 | static u64 notrace sun50i_a64_read_cntvct_el0(void) |
| 367 | { |
| 368 | return __sun50i_a64_read_reg(cntvct_el0); |
| 369 | } |
| 370 | |
| 371 | static u32 notrace sun50i_a64_read_cntp_tval_el0(void) |
| 372 | { |
| 373 | return read_sysreg(cntp_cval_el0) - sun50i_a64_read_cntpct_el0(); |
| 374 | } |
| 375 | |
| 376 | static u32 notrace sun50i_a64_read_cntv_tval_el0(void) |
| 377 | { |
| 378 | return read_sysreg(cntv_cval_el0) - sun50i_a64_read_cntvct_el0(); |
| 379 | } |
| 380 | #endif |
| 381 | |
| 382 | #ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND |
| 383 | DEFINE_PER_CPU(const struct arch_timer_erratum_workaround *, timer_unstable_counter_workaround); |
| 384 | EXPORT_SYMBOL_GPL(timer_unstable_counter_workaround); |
| 385 | |
| 386 | static atomic_t timer_unstable_counter_workaround_in_use = ATOMIC_INIT(0); |
| 387 | |
| 388 | static void erratum_set_next_event_tval_generic(const int access, unsigned long evt, |
| 389 | struct clock_event_device *clk) |
| 390 | { |
| 391 | unsigned long ctrl; |
| 392 | u64 cval; |
| 393 | |
| 394 | ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL, clk); |
| 395 | ctrl |= ARCH_TIMER_CTRL_ENABLE; |
| 396 | ctrl &= ~ARCH_TIMER_CTRL_IT_MASK; |
| 397 | |
| 398 | if (access == ARCH_TIMER_PHYS_ACCESS) { |
| 399 | cval = evt + arch_counter_get_cntpct_stable(); |
| 400 | write_sysreg(cval, cntp_cval_el0); |
| 401 | } else { |
| 402 | cval = evt + arch_counter_get_cntvct_stable(); |
| 403 | write_sysreg(cval, cntv_cval_el0); |
| 404 | } |
| 405 | |
| 406 | arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk); |
| 407 | } |
| 408 | |
| 409 | static __maybe_unused int erratum_set_next_event_tval_virt(unsigned long evt, |
| 410 | struct clock_event_device *clk) |
| 411 | { |
| 412 | erratum_set_next_event_tval_generic(ARCH_TIMER_VIRT_ACCESS, evt, clk); |
| 413 | return 0; |
| 414 | } |
| 415 | |
| 416 | static __maybe_unused int erratum_set_next_event_tval_phys(unsigned long evt, |
| 417 | struct clock_event_device *clk) |
| 418 | { |
| 419 | erratum_set_next_event_tval_generic(ARCH_TIMER_PHYS_ACCESS, evt, clk); |
| 420 | return 0; |
| 421 | } |
| 422 | |
| 423 | static const struct arch_timer_erratum_workaround ool_workarounds[] = { |
| 424 | #ifdef CONFIG_FSL_ERRATUM_A008585 |
| 425 | { |
| 426 | .match_type = ate_match_dt, |
| 427 | .id = "fsl,erratum-a008585", |
| 428 | .desc = "Freescale erratum a005858", |
| 429 | .read_cntp_tval_el0 = fsl_a008585_read_cntp_tval_el0, |
| 430 | .read_cntv_tval_el0 = fsl_a008585_read_cntv_tval_el0, |
| 431 | .read_cntpct_el0 = fsl_a008585_read_cntpct_el0, |
| 432 | .read_cntvct_el0 = fsl_a008585_read_cntvct_el0, |
| 433 | .set_next_event_phys = erratum_set_next_event_tval_phys, |
| 434 | .set_next_event_virt = erratum_set_next_event_tval_virt, |
| 435 | }, |
| 436 | #endif |
| 437 | #ifdef CONFIG_HISILICON_ERRATUM_161010101 |
| 438 | { |
| 439 | .match_type = ate_match_dt, |
| 440 | .id = "hisilicon,erratum-161010101", |
| 441 | .desc = "HiSilicon erratum 161010101", |
| 442 | .read_cntp_tval_el0 = hisi_161010101_read_cntp_tval_el0, |
| 443 | .read_cntv_tval_el0 = hisi_161010101_read_cntv_tval_el0, |
| 444 | .read_cntpct_el0 = hisi_161010101_read_cntpct_el0, |
| 445 | .read_cntvct_el0 = hisi_161010101_read_cntvct_el0, |
| 446 | .set_next_event_phys = erratum_set_next_event_tval_phys, |
| 447 | .set_next_event_virt = erratum_set_next_event_tval_virt, |
| 448 | }, |
| 449 | { |
| 450 | .match_type = ate_match_acpi_oem_info, |
| 451 | .id = hisi_161010101_oem_info, |
| 452 | .desc = "HiSilicon erratum 161010101", |
| 453 | .read_cntp_tval_el0 = hisi_161010101_read_cntp_tval_el0, |
| 454 | .read_cntv_tval_el0 = hisi_161010101_read_cntv_tval_el0, |
| 455 | .read_cntpct_el0 = hisi_161010101_read_cntpct_el0, |
| 456 | .read_cntvct_el0 = hisi_161010101_read_cntvct_el0, |
| 457 | .set_next_event_phys = erratum_set_next_event_tval_phys, |
| 458 | .set_next_event_virt = erratum_set_next_event_tval_virt, |
| 459 | }, |
| 460 | #endif |
| 461 | #ifdef CONFIG_ARM64_ERRATUM_858921 |
| 462 | { |
| 463 | .match_type = ate_match_local_cap_id, |
| 464 | .id = (void *)ARM64_WORKAROUND_858921, |
| 465 | .desc = "ARM erratum 858921", |
| 466 | .read_cntpct_el0 = arm64_858921_read_cntpct_el0, |
| 467 | .read_cntvct_el0 = arm64_858921_read_cntvct_el0, |
| 468 | }, |
| 469 | #endif |
| 470 | #ifdef CONFIG_SUN50I_ERRATUM_UNKNOWN1 |
| 471 | { |
| 472 | .match_type = ate_match_dt, |
| 473 | .id = "allwinner,erratum-unknown1", |
| 474 | .desc = "Allwinner erratum UNKNOWN1", |
| 475 | .read_cntp_tval_el0 = sun50i_a64_read_cntp_tval_el0, |
| 476 | .read_cntv_tval_el0 = sun50i_a64_read_cntv_tval_el0, |
| 477 | .read_cntpct_el0 = sun50i_a64_read_cntpct_el0, |
| 478 | .read_cntvct_el0 = sun50i_a64_read_cntvct_el0, |
| 479 | .set_next_event_phys = erratum_set_next_event_tval_phys, |
| 480 | .set_next_event_virt = erratum_set_next_event_tval_virt, |
| 481 | }, |
| 482 | #endif |
| 483 | #ifdef CONFIG_ARM64_ERRATUM_1418040 |
| 484 | { |
| 485 | .match_type = ate_match_local_cap_id, |
| 486 | .id = (void *)ARM64_WORKAROUND_1418040, |
| 487 | .desc = "ARM erratum 1418040", |
| 488 | .disable_compat_vdso = true, |
| 489 | }, |
| 490 | #endif |
| 491 | }; |
| 492 | |
| 493 | typedef bool (*ate_match_fn_t)(const struct arch_timer_erratum_workaround *, |
| 494 | const void *); |
| 495 | |
| 496 | static |
| 497 | bool arch_timer_check_dt_erratum(const struct arch_timer_erratum_workaround *wa, |
| 498 | const void *arg) |
| 499 | { |
| 500 | const struct device_node *np = arg; |
| 501 | |
| 502 | return of_property_read_bool(np, wa->id); |
| 503 | } |
| 504 | |
| 505 | static |
| 506 | bool arch_timer_check_local_cap_erratum(const struct arch_timer_erratum_workaround *wa, |
| 507 | const void *arg) |
| 508 | { |
| 509 | return this_cpu_has_cap((uintptr_t)wa->id); |
| 510 | } |
| 511 | |
| 512 | |
| 513 | static |
| 514 | bool arch_timer_check_acpi_oem_erratum(const struct arch_timer_erratum_workaround *wa, |
| 515 | const void *arg) |
| 516 | { |
| 517 | static const struct ate_acpi_oem_info empty_oem_info = {}; |
| 518 | const struct ate_acpi_oem_info *info = wa->id; |
| 519 | const struct acpi_table_header *table = arg; |
| 520 | |
| 521 | /* Iterate over the ACPI OEM info array, looking for a match */ |
| 522 | while (memcmp(info, &empty_oem_info, sizeof(*info))) { |
| 523 | if (!memcmp(info->oem_id, table->oem_id, ACPI_OEM_ID_SIZE) && |
| 524 | !memcmp(info->oem_table_id, table->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) && |
| 525 | info->oem_revision == table->oem_revision) |
| 526 | return true; |
| 527 | |
| 528 | info++; |
| 529 | } |
| 530 | |
| 531 | return false; |
| 532 | } |
| 533 | |
| 534 | static const struct arch_timer_erratum_workaround * |
| 535 | arch_timer_iterate_errata(enum arch_timer_erratum_match_type type, |
| 536 | ate_match_fn_t match_fn, |
| 537 | void *arg) |
| 538 | { |
| 539 | int i; |
| 540 | |
| 541 | for (i = 0; i < ARRAY_SIZE(ool_workarounds); i++) { |
| 542 | if (ool_workarounds[i].match_type != type) |
| 543 | continue; |
| 544 | |
| 545 | if (match_fn(&ool_workarounds[i], arg)) |
| 546 | return &ool_workarounds[i]; |
| 547 | } |
| 548 | |
| 549 | return NULL; |
| 550 | } |
| 551 | |
| 552 | static |
| 553 | void arch_timer_enable_workaround(const struct arch_timer_erratum_workaround *wa, |
| 554 | bool local) |
| 555 | { |
| 556 | int i; |
| 557 | |
| 558 | if (local) { |
| 559 | __this_cpu_write(timer_unstable_counter_workaround, wa); |
| 560 | } else { |
| 561 | for_each_possible_cpu(i) |
| 562 | per_cpu(timer_unstable_counter_workaround, i) = wa; |
| 563 | } |
| 564 | |
| 565 | if (wa->read_cntvct_el0 || wa->read_cntpct_el0) |
| 566 | atomic_set(&timer_unstable_counter_workaround_in_use, 1); |
| 567 | |
| 568 | /* |
| 569 | * Don't use the vdso fastpath if errata require using the |
| 570 | * out-of-line counter accessor. We may change our mind pretty |
| 571 | * late in the game (with a per-CPU erratum, for example), so |
| 572 | * change both the default value and the vdso itself. |
| 573 | */ |
| 574 | if (wa->read_cntvct_el0) { |
| 575 | clocksource_counter.vdso_clock_mode = VDSO_CLOCKMODE_NONE; |
| 576 | vdso_default = VDSO_CLOCKMODE_NONE; |
| 577 | } else if (wa->disable_compat_vdso && vdso_default != VDSO_CLOCKMODE_NONE) { |
| 578 | vdso_default = VDSO_CLOCKMODE_ARCHTIMER_NOCOMPAT; |
| 579 | clocksource_counter.vdso_clock_mode = vdso_default; |
| 580 | } |
| 581 | } |
| 582 | |
| 583 | static void arch_timer_check_ool_workaround(enum arch_timer_erratum_match_type type, |
| 584 | void *arg) |
| 585 | { |
| 586 | const struct arch_timer_erratum_workaround *wa, *__wa; |
| 587 | ate_match_fn_t match_fn = NULL; |
| 588 | bool local = false; |
| 589 | |
| 590 | switch (type) { |
| 591 | case ate_match_dt: |
| 592 | match_fn = arch_timer_check_dt_erratum; |
| 593 | break; |
| 594 | case ate_match_local_cap_id: |
| 595 | match_fn = arch_timer_check_local_cap_erratum; |
| 596 | local = true; |
| 597 | break; |
| 598 | case ate_match_acpi_oem_info: |
| 599 | match_fn = arch_timer_check_acpi_oem_erratum; |
| 600 | break; |
| 601 | default: |
| 602 | WARN_ON(1); |
| 603 | return; |
| 604 | } |
| 605 | |
| 606 | wa = arch_timer_iterate_errata(type, match_fn, arg); |
| 607 | if (!wa) |
| 608 | return; |
| 609 | |
| 610 | __wa = __this_cpu_read(timer_unstable_counter_workaround); |
| 611 | if (__wa && wa != __wa) |
| 612 | pr_warn("Can't enable workaround for %s (clashes with %s\n)", |
| 613 | wa->desc, __wa->desc); |
| 614 | |
| 615 | if (__wa) |
| 616 | return; |
| 617 | |
| 618 | arch_timer_enable_workaround(wa, local); |
| 619 | pr_info("Enabling %s workaround for %s\n", |
| 620 | local ? "local" : "global", wa->desc); |
| 621 | } |
| 622 | |
| 623 | static bool arch_timer_this_cpu_has_cntvct_wa(void) |
| 624 | { |
| 625 | return has_erratum_handler(read_cntvct_el0); |
| 626 | } |
| 627 | |
| 628 | static bool arch_timer_counter_has_wa(void) |
| 629 | { |
| 630 | return atomic_read(&timer_unstable_counter_workaround_in_use); |
| 631 | } |
| 632 | #else |
| 633 | #define arch_timer_check_ool_workaround(t,a) do { } while(0) |
| 634 | #define arch_timer_this_cpu_has_cntvct_wa() ({false;}) |
| 635 | #define arch_timer_counter_has_wa() ({false;}) |
| 636 | #endif /* CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND */ |
| 637 | |
| 638 | static __always_inline irqreturn_t timer_handler(const int access, |
| 639 | struct clock_event_device *evt) |
| 640 | { |
| 641 | unsigned long ctrl; |
| 642 | |
| 643 | ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL, evt); |
| 644 | if (ctrl & ARCH_TIMER_CTRL_IT_STAT) { |
| 645 | ctrl |= ARCH_TIMER_CTRL_IT_MASK; |
| 646 | arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, evt); |
| 647 | evt->event_handler(evt); |
| 648 | return IRQ_HANDLED; |
| 649 | } |
| 650 | |
| 651 | return IRQ_NONE; |
| 652 | } |
| 653 | |
| 654 | static irqreturn_t arch_timer_handler_virt(int irq, void *dev_id) |
| 655 | { |
| 656 | struct clock_event_device *evt = dev_id; |
| 657 | |
| 658 | return timer_handler(ARCH_TIMER_VIRT_ACCESS, evt); |
| 659 | } |
| 660 | |
| 661 | static irqreturn_t arch_timer_handler_phys(int irq, void *dev_id) |
| 662 | { |
| 663 | struct clock_event_device *evt = dev_id; |
| 664 | |
| 665 | return timer_handler(ARCH_TIMER_PHYS_ACCESS, evt); |
| 666 | } |
| 667 | |
| 668 | static irqreturn_t arch_timer_handler_phys_mem(int irq, void *dev_id) |
| 669 | { |
| 670 | struct clock_event_device *evt = dev_id; |
| 671 | |
| 672 | return timer_handler(ARCH_TIMER_MEM_PHYS_ACCESS, evt); |
| 673 | } |
| 674 | |
| 675 | static irqreturn_t arch_timer_handler_virt_mem(int irq, void *dev_id) |
| 676 | { |
| 677 | struct clock_event_device *evt = dev_id; |
| 678 | |
| 679 | return timer_handler(ARCH_TIMER_MEM_VIRT_ACCESS, evt); |
| 680 | } |
| 681 | |
| 682 | static __always_inline int timer_shutdown(const int access, |
| 683 | struct clock_event_device *clk) |
| 684 | { |
| 685 | unsigned long ctrl; |
| 686 | |
| 687 | ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL, clk); |
| 688 | ctrl &= ~ARCH_TIMER_CTRL_ENABLE; |
| 689 | arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk); |
| 690 | |
| 691 | return 0; |
| 692 | } |
| 693 | |
| 694 | static int arch_timer_shutdown_virt(struct clock_event_device *clk) |
| 695 | { |
| 696 | return timer_shutdown(ARCH_TIMER_VIRT_ACCESS, clk); |
| 697 | } |
| 698 | |
| 699 | static int arch_timer_shutdown_phys(struct clock_event_device *clk) |
| 700 | { |
| 701 | return timer_shutdown(ARCH_TIMER_PHYS_ACCESS, clk); |
| 702 | } |
| 703 | |
| 704 | static int arch_timer_shutdown_virt_mem(struct clock_event_device *clk) |
| 705 | { |
| 706 | return timer_shutdown(ARCH_TIMER_MEM_VIRT_ACCESS, clk); |
| 707 | } |
| 708 | |
| 709 | static int arch_timer_shutdown_phys_mem(struct clock_event_device *clk) |
| 710 | { |
| 711 | return timer_shutdown(ARCH_TIMER_MEM_PHYS_ACCESS, clk); |
| 712 | } |
| 713 | |
| 714 | static __always_inline void set_next_event(const int access, unsigned long evt, |
| 715 | struct clock_event_device *clk) |
| 716 | { |
| 717 | unsigned long ctrl; |
| 718 | ctrl = arch_timer_reg_read(access, ARCH_TIMER_REG_CTRL, clk); |
| 719 | ctrl |= ARCH_TIMER_CTRL_ENABLE; |
| 720 | ctrl &= ~ARCH_TIMER_CTRL_IT_MASK; |
| 721 | arch_timer_reg_write(access, ARCH_TIMER_REG_TVAL, evt, clk); |
| 722 | arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk); |
| 723 | } |
| 724 | |
| 725 | static int arch_timer_set_next_event_virt(unsigned long evt, |
| 726 | struct clock_event_device *clk) |
| 727 | { |
| 728 | set_next_event(ARCH_TIMER_VIRT_ACCESS, evt, clk); |
| 729 | return 0; |
| 730 | } |
| 731 | |
| 732 | static int arch_timer_set_next_event_phys(unsigned long evt, |
| 733 | struct clock_event_device *clk) |
| 734 | { |
| 735 | set_next_event(ARCH_TIMER_PHYS_ACCESS, evt, clk); |
| 736 | return 0; |
| 737 | } |
| 738 | |
| 739 | static int arch_timer_set_next_event_virt_mem(unsigned long evt, |
| 740 | struct clock_event_device *clk) |
| 741 | { |
| 742 | set_next_event(ARCH_TIMER_MEM_VIRT_ACCESS, evt, clk); |
| 743 | return 0; |
| 744 | } |
| 745 | |
| 746 | static int arch_timer_set_next_event_phys_mem(unsigned long evt, |
| 747 | struct clock_event_device *clk) |
| 748 | { |
| 749 | set_next_event(ARCH_TIMER_MEM_PHYS_ACCESS, evt, clk); |
| 750 | return 0; |
| 751 | } |
| 752 | |
| 753 | static void __arch_timer_setup(unsigned type, |
| 754 | struct clock_event_device *clk) |
| 755 | { |
| 756 | clk->features = CLOCK_EVT_FEAT_ONESHOT; |
| 757 | |
| 758 | if (type == ARCH_TIMER_TYPE_CP15) { |
| 759 | typeof(clk->set_next_event) sne; |
| 760 | |
| 761 | arch_timer_check_ool_workaround(ate_match_local_cap_id, NULL); |
| 762 | |
| 763 | if (arch_timer_c3stop) |
| 764 | clk->features |= CLOCK_EVT_FEAT_C3STOP; |
| 765 | clk->name = "arch_sys_timer"; |
| 766 | clk->rating = 450; |
| 767 | clk->cpumask = cpumask_of(smp_processor_id()); |
| 768 | clk->irq = arch_timer_ppi[arch_timer_uses_ppi]; |
| 769 | switch (arch_timer_uses_ppi) { |
| 770 | case ARCH_TIMER_VIRT_PPI: |
| 771 | clk->set_state_shutdown = arch_timer_shutdown_virt; |
| 772 | clk->set_state_oneshot_stopped = arch_timer_shutdown_virt; |
| 773 | sne = erratum_handler(set_next_event_virt); |
| 774 | break; |
| 775 | case ARCH_TIMER_PHYS_SECURE_PPI: |
| 776 | case ARCH_TIMER_PHYS_NONSECURE_PPI: |
| 777 | case ARCH_TIMER_HYP_PPI: |
| 778 | clk->set_state_shutdown = arch_timer_shutdown_phys; |
| 779 | clk->set_state_oneshot_stopped = arch_timer_shutdown_phys; |
| 780 | sne = erratum_handler(set_next_event_phys); |
| 781 | break; |
| 782 | default: |
| 783 | BUG(); |
| 784 | } |
| 785 | |
| 786 | clk->set_next_event = sne; |
| 787 | } else { |
| 788 | clk->features |= CLOCK_EVT_FEAT_DYNIRQ; |
| 789 | clk->name = "arch_mem_timer"; |
| 790 | clk->rating = 400; |
| 791 | clk->cpumask = cpu_possible_mask; |
| 792 | if (arch_timer_mem_use_virtual) { |
| 793 | clk->set_state_shutdown = arch_timer_shutdown_virt_mem; |
| 794 | clk->set_state_oneshot_stopped = arch_timer_shutdown_virt_mem; |
| 795 | clk->set_next_event = |
| 796 | arch_timer_set_next_event_virt_mem; |
| 797 | } else { |
| 798 | clk->set_state_shutdown = arch_timer_shutdown_phys_mem; |
| 799 | clk->set_state_oneshot_stopped = arch_timer_shutdown_phys_mem; |
| 800 | clk->set_next_event = |
| 801 | arch_timer_set_next_event_phys_mem; |
| 802 | } |
| 803 | } |
| 804 | |
| 805 | clk->set_state_shutdown(clk); |
| 806 | |
| 807 | clockevents_config_and_register(clk, arch_timer_rate, 0xf, 0x7fffffff); |
| 808 | } |
| 809 | |
| 810 | static void arch_timer_evtstrm_enable(int divider) |
| 811 | { |
| 812 | u32 cntkctl = arch_timer_get_cntkctl(); |
| 813 | |
| 814 | cntkctl &= ~ARCH_TIMER_EVT_TRIGGER_MASK; |
| 815 | /* Set the divider and enable virtual event stream */ |
| 816 | cntkctl |= (divider << ARCH_TIMER_EVT_TRIGGER_SHIFT) |
| 817 | | ARCH_TIMER_VIRT_EVT_EN; |
| 818 | arch_timer_set_cntkctl(cntkctl); |
| 819 | arch_timer_set_evtstrm_feature(); |
| 820 | cpumask_set_cpu(smp_processor_id(), &evtstrm_available); |
| 821 | } |
| 822 | |
| 823 | static void arch_timer_configure_evtstream(void) |
| 824 | { |
| 825 | int evt_stream_div, lsb; |
| 826 | |
| 827 | /* |
| 828 | * As the event stream can at most be generated at half the frequency |
| 829 | * of the counter, use half the frequency when computing the divider. |
| 830 | */ |
| 831 | evt_stream_div = arch_timer_rate / ARCH_TIMER_EVT_STREAM_FREQ / 2; |
| 832 | |
| 833 | /* |
| 834 | * Find the closest power of two to the divisor. If the adjacent bit |
| 835 | * of lsb (last set bit, starts from 0) is set, then we use (lsb + 1). |
| 836 | */ |
| 837 | lsb = fls(evt_stream_div) - 1; |
| 838 | if (lsb > 0 && (evt_stream_div & BIT(lsb - 1))) |
| 839 | lsb++; |
| 840 | |
| 841 | /* enable event stream */ |
| 842 | arch_timer_evtstrm_enable(max(0, min(lsb, 15))); |
| 843 | } |
| 844 | |
| 845 | static void arch_counter_set_user_access(void) |
| 846 | { |
| 847 | u32 cntkctl = arch_timer_get_cntkctl(); |
| 848 | |
| 849 | /* Disable user access to the timers and both counters */ |
| 850 | /* Also disable virtual event stream */ |
| 851 | cntkctl &= ~(ARCH_TIMER_USR_PT_ACCESS_EN |
| 852 | | ARCH_TIMER_USR_VT_ACCESS_EN |
| 853 | | ARCH_TIMER_USR_VCT_ACCESS_EN |
| 854 | | ARCH_TIMER_VIRT_EVT_EN |
| 855 | | ARCH_TIMER_USR_PCT_ACCESS_EN); |
| 856 | |
| 857 | /* |
| 858 | * Enable user access to the virtual counter if it doesn't |
| 859 | * need to be workaround. The vdso may have been already |
| 860 | * disabled though. |
| 861 | */ |
| 862 | if (arch_timer_this_cpu_has_cntvct_wa()) |
| 863 | pr_info("CPU%d: Trapping CNTVCT access\n", smp_processor_id()); |
| 864 | else |
| 865 | cntkctl |= ARCH_TIMER_USR_VCT_ACCESS_EN; |
| 866 | |
| 867 | arch_timer_set_cntkctl(cntkctl); |
| 868 | } |
| 869 | |
| 870 | static bool arch_timer_has_nonsecure_ppi(void) |
| 871 | { |
| 872 | return (arch_timer_uses_ppi == ARCH_TIMER_PHYS_SECURE_PPI && |
| 873 | arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]); |
| 874 | } |
| 875 | |
| 876 | static u32 check_ppi_trigger(int irq) |
| 877 | { |
| 878 | u32 flags = irq_get_trigger_type(irq); |
| 879 | |
| 880 | if (flags != IRQF_TRIGGER_HIGH && flags != IRQF_TRIGGER_LOW) { |
| 881 | pr_warn("WARNING: Invalid trigger for IRQ%d, assuming level low\n", irq); |
| 882 | pr_warn("WARNING: Please fix your firmware\n"); |
| 883 | flags = IRQF_TRIGGER_LOW; |
| 884 | } |
| 885 | |
| 886 | return flags; |
| 887 | } |
| 888 | |
| 889 | static int arch_timer_starting_cpu(unsigned int cpu) |
| 890 | { |
| 891 | struct clock_event_device *clk = this_cpu_ptr(arch_timer_evt); |
| 892 | u32 flags; |
| 893 | |
| 894 | __arch_timer_setup(ARCH_TIMER_TYPE_CP15, clk); |
| 895 | |
| 896 | flags = check_ppi_trigger(arch_timer_ppi[arch_timer_uses_ppi]); |
| 897 | enable_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi], flags); |
| 898 | |
| 899 | if (arch_timer_has_nonsecure_ppi()) { |
| 900 | flags = check_ppi_trigger(arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]); |
| 901 | enable_percpu_irq(arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI], |
| 902 | flags); |
| 903 | } |
| 904 | |
| 905 | arch_counter_set_user_access(); |
| 906 | if (evtstrm_enable) |
| 907 | arch_timer_configure_evtstream(); |
| 908 | |
| 909 | return 0; |
| 910 | } |
| 911 | |
| 912 | static int validate_timer_rate(void) |
| 913 | { |
| 914 | if (!arch_timer_rate) |
| 915 | return -EINVAL; |
| 916 | |
| 917 | /* Arch timer frequency < 1MHz can cause trouble */ |
| 918 | WARN_ON(arch_timer_rate < 1000000); |
| 919 | |
| 920 | return 0; |
| 921 | } |
| 922 | |
| 923 | /* |
| 924 | * For historical reasons, when probing with DT we use whichever (non-zero) |
| 925 | * rate was probed first, and don't verify that others match. If the first node |
| 926 | * probed has a clock-frequency property, this overrides the HW register. |
| 927 | */ |
| 928 | static void arch_timer_of_configure_rate(u32 rate, struct device_node *np) |
| 929 | { |
| 930 | /* Who has more than one independent system counter? */ |
| 931 | if (arch_timer_rate) |
| 932 | return; |
| 933 | |
| 934 | if (of_property_read_u32(np, "clock-frequency", &arch_timer_rate)) |
| 935 | arch_timer_rate = rate; |
| 936 | |
| 937 | /* Check the timer frequency. */ |
| 938 | if (validate_timer_rate()) |
| 939 | pr_warn("frequency not available\n"); |
| 940 | } |
| 941 | |
| 942 | static void arch_timer_banner(unsigned type) |
| 943 | { |
| 944 | pr_info("%s%s%s timer(s) running at %lu.%02luMHz (%s%s%s).\n", |
| 945 | type & ARCH_TIMER_TYPE_CP15 ? "cp15" : "", |
| 946 | type == (ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM) ? |
| 947 | " and " : "", |
| 948 | type & ARCH_TIMER_TYPE_MEM ? "mmio" : "", |
| 949 | (unsigned long)arch_timer_rate / 1000000, |
| 950 | (unsigned long)(arch_timer_rate / 10000) % 100, |
| 951 | type & ARCH_TIMER_TYPE_CP15 ? |
| 952 | (arch_timer_uses_ppi == ARCH_TIMER_VIRT_PPI) ? "virt" : "phys" : |
| 953 | "", |
| 954 | type == (ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM) ? "/" : "", |
| 955 | type & ARCH_TIMER_TYPE_MEM ? |
| 956 | arch_timer_mem_use_virtual ? "virt" : "phys" : |
| 957 | ""); |
| 958 | } |
| 959 | |
| 960 | u32 arch_timer_get_rate(void) |
| 961 | { |
| 962 | return arch_timer_rate; |
| 963 | } |
| 964 | |
| 965 | bool arch_timer_evtstrm_available(void) |
| 966 | { |
| 967 | /* |
| 968 | * We might get called from a preemptible context. This is fine |
| 969 | * because availability of the event stream should be always the same |
| 970 | * for a preemptible context and context where we might resume a task. |
| 971 | */ |
| 972 | return cpumask_test_cpu(raw_smp_processor_id(), &evtstrm_available); |
| 973 | } |
| 974 | |
| 975 | static u64 arch_counter_get_cntvct_mem(void) |
| 976 | { |
| 977 | u32 vct_lo, vct_hi, tmp_hi; |
| 978 | |
| 979 | do { |
| 980 | vct_hi = readl_relaxed(arch_counter_base + CNTVCT_HI); |
| 981 | vct_lo = readl_relaxed(arch_counter_base + CNTVCT_LO); |
| 982 | tmp_hi = readl_relaxed(arch_counter_base + CNTVCT_HI); |
| 983 | } while (vct_hi != tmp_hi); |
| 984 | |
| 985 | return ((u64) vct_hi << 32) | vct_lo; |
| 986 | } |
| 987 | |
| 988 | static struct arch_timer_kvm_info arch_timer_kvm_info; |
| 989 | |
| 990 | struct arch_timer_kvm_info *arch_timer_get_kvm_info(void) |
| 991 | { |
| 992 | return &arch_timer_kvm_info; |
| 993 | } |
| 994 | |
| 995 | static void __init arch_counter_register(unsigned type) |
| 996 | { |
| 997 | u64 start_count; |
| 998 | |
| 999 | /* Register the CP15 based counter if we have one */ |
| 1000 | if (type & ARCH_TIMER_TYPE_CP15) { |
| 1001 | u64 (*rd)(void); |
| 1002 | |
| 1003 | if ((IS_ENABLED(CONFIG_ARM64) && !is_hyp_mode_available()) || |
| 1004 | arch_timer_uses_ppi == ARCH_TIMER_VIRT_PPI) { |
| 1005 | if (arch_timer_counter_has_wa()) |
| 1006 | rd = arch_counter_get_cntvct_stable; |
| 1007 | else |
| 1008 | rd = arch_counter_get_cntvct; |
| 1009 | } else { |
| 1010 | if (arch_timer_counter_has_wa()) |
| 1011 | rd = arch_counter_get_cntpct_stable; |
| 1012 | else |
| 1013 | rd = arch_counter_get_cntpct; |
| 1014 | } |
| 1015 | |
| 1016 | arch_timer_read_counter = rd; |
| 1017 | clocksource_counter.vdso_clock_mode = vdso_default; |
| 1018 | } else { |
| 1019 | arch_timer_read_counter = arch_counter_get_cntvct_mem; |
| 1020 | } |
| 1021 | |
| 1022 | if (!arch_counter_suspend_stop) |
| 1023 | clocksource_counter.flags |= CLOCK_SOURCE_SUSPEND_NONSTOP; |
| 1024 | start_count = arch_timer_read_counter(); |
| 1025 | clocksource_register_hz(&clocksource_counter, arch_timer_rate); |
| 1026 | cyclecounter.mult = clocksource_counter.mult; |
| 1027 | cyclecounter.shift = clocksource_counter.shift; |
| 1028 | timecounter_init(&arch_timer_kvm_info.timecounter, |
| 1029 | &cyclecounter, start_count); |
| 1030 | |
| 1031 | /* 56 bits minimum, so we assume worst case rollover */ |
| 1032 | sched_clock_register(arch_timer_read_counter, 56, arch_timer_rate); |
| 1033 | } |
| 1034 | |
| 1035 | static void arch_timer_stop(struct clock_event_device *clk) |
| 1036 | { |
| 1037 | pr_debug("disable IRQ%d cpu #%d\n", clk->irq, smp_processor_id()); |
| 1038 | |
| 1039 | disable_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi]); |
| 1040 | if (arch_timer_has_nonsecure_ppi()) |
| 1041 | disable_percpu_irq(arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]); |
| 1042 | |
| 1043 | clk->set_state_shutdown(clk); |
| 1044 | } |
| 1045 | |
| 1046 | static int arch_timer_dying_cpu(unsigned int cpu) |
| 1047 | { |
| 1048 | struct clock_event_device *clk = this_cpu_ptr(arch_timer_evt); |
| 1049 | |
| 1050 | cpumask_clear_cpu(smp_processor_id(), &evtstrm_available); |
| 1051 | |
| 1052 | arch_timer_stop(clk); |
| 1053 | return 0; |
| 1054 | } |
| 1055 | |
| 1056 | #ifdef CONFIG_CPU_PM |
| 1057 | static DEFINE_PER_CPU(unsigned long, saved_cntkctl); |
| 1058 | static int arch_timer_cpu_pm_notify(struct notifier_block *self, |
| 1059 | unsigned long action, void *hcpu) |
| 1060 | { |
| 1061 | if (action == CPU_PM_ENTER) { |
| 1062 | __this_cpu_write(saved_cntkctl, arch_timer_get_cntkctl()); |
| 1063 | |
| 1064 | cpumask_clear_cpu(smp_processor_id(), &evtstrm_available); |
| 1065 | } else if (action == CPU_PM_ENTER_FAILED || action == CPU_PM_EXIT) { |
| 1066 | arch_timer_set_cntkctl(__this_cpu_read(saved_cntkctl)); |
| 1067 | |
| 1068 | if (arch_timer_have_evtstrm_feature()) |
| 1069 | cpumask_set_cpu(smp_processor_id(), &evtstrm_available); |
| 1070 | } |
| 1071 | return NOTIFY_OK; |
| 1072 | } |
| 1073 | |
| 1074 | static struct notifier_block arch_timer_cpu_pm_notifier = { |
| 1075 | .notifier_call = arch_timer_cpu_pm_notify, |
| 1076 | }; |
| 1077 | |
| 1078 | static int __init arch_timer_cpu_pm_init(void) |
| 1079 | { |
| 1080 | return cpu_pm_register_notifier(&arch_timer_cpu_pm_notifier); |
| 1081 | } |
| 1082 | |
| 1083 | static void __init arch_timer_cpu_pm_deinit(void) |
| 1084 | { |
| 1085 | WARN_ON(cpu_pm_unregister_notifier(&arch_timer_cpu_pm_notifier)); |
| 1086 | } |
| 1087 | |
| 1088 | #else |
| 1089 | static int __init arch_timer_cpu_pm_init(void) |
| 1090 | { |
| 1091 | return 0; |
| 1092 | } |
| 1093 | |
| 1094 | static void __init arch_timer_cpu_pm_deinit(void) |
| 1095 | { |
| 1096 | } |
| 1097 | #endif |
| 1098 | |
| 1099 | static int __init arch_timer_register(void) |
| 1100 | { |
| 1101 | int err; |
| 1102 | int ppi; |
| 1103 | |
| 1104 | arch_timer_evt = alloc_percpu(struct clock_event_device); |
| 1105 | if (!arch_timer_evt) { |
| 1106 | err = -ENOMEM; |
| 1107 | goto out; |
| 1108 | } |
| 1109 | |
| 1110 | ppi = arch_timer_ppi[arch_timer_uses_ppi]; |
| 1111 | switch (arch_timer_uses_ppi) { |
| 1112 | case ARCH_TIMER_VIRT_PPI: |
| 1113 | err = request_percpu_irq(ppi, arch_timer_handler_virt, |
| 1114 | "arch_timer", arch_timer_evt); |
| 1115 | break; |
| 1116 | case ARCH_TIMER_PHYS_SECURE_PPI: |
| 1117 | case ARCH_TIMER_PHYS_NONSECURE_PPI: |
| 1118 | err = request_percpu_irq(ppi, arch_timer_handler_phys, |
| 1119 | "arch_timer", arch_timer_evt); |
| 1120 | if (!err && arch_timer_has_nonsecure_ppi()) { |
| 1121 | ppi = arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]; |
| 1122 | err = request_percpu_irq(ppi, arch_timer_handler_phys, |
| 1123 | "arch_timer", arch_timer_evt); |
| 1124 | if (err) |
| 1125 | free_percpu_irq(arch_timer_ppi[ARCH_TIMER_PHYS_SECURE_PPI], |
| 1126 | arch_timer_evt); |
| 1127 | } |
| 1128 | break; |
| 1129 | case ARCH_TIMER_HYP_PPI: |
| 1130 | err = request_percpu_irq(ppi, arch_timer_handler_phys, |
| 1131 | "arch_timer", arch_timer_evt); |
| 1132 | break; |
| 1133 | default: |
| 1134 | BUG(); |
| 1135 | } |
| 1136 | |
| 1137 | if (err) { |
| 1138 | pr_err("can't register interrupt %d (%d)\n", ppi, err); |
| 1139 | goto out_free; |
| 1140 | } |
| 1141 | |
| 1142 | err = arch_timer_cpu_pm_init(); |
| 1143 | if (err) |
| 1144 | goto out_unreg_notify; |
| 1145 | |
| 1146 | /* Register and immediately configure the timer on the boot CPU */ |
| 1147 | err = cpuhp_setup_state(CPUHP_AP_ARM_ARCH_TIMER_STARTING, |
| 1148 | "clockevents/arm/arch_timer:starting", |
| 1149 | arch_timer_starting_cpu, arch_timer_dying_cpu); |
| 1150 | if (err) |
| 1151 | goto out_unreg_cpupm; |
| 1152 | return 0; |
| 1153 | |
| 1154 | out_unreg_cpupm: |
| 1155 | arch_timer_cpu_pm_deinit(); |
| 1156 | |
| 1157 | out_unreg_notify: |
| 1158 | free_percpu_irq(arch_timer_ppi[arch_timer_uses_ppi], arch_timer_evt); |
| 1159 | if (arch_timer_has_nonsecure_ppi()) |
| 1160 | free_percpu_irq(arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI], |
| 1161 | arch_timer_evt); |
| 1162 | |
| 1163 | out_free: |
| 1164 | free_percpu(arch_timer_evt); |
| 1165 | out: |
| 1166 | return err; |
| 1167 | } |
| 1168 | |
| 1169 | static int __init arch_timer_mem_register(void __iomem *base, unsigned int irq) |
| 1170 | { |
| 1171 | int ret; |
| 1172 | irq_handler_t func; |
| 1173 | struct arch_timer *t; |
| 1174 | |
| 1175 | t = kzalloc(sizeof(*t), GFP_KERNEL); |
| 1176 | if (!t) |
| 1177 | return -ENOMEM; |
| 1178 | |
| 1179 | t->base = base; |
| 1180 | t->evt.irq = irq; |
| 1181 | __arch_timer_setup(ARCH_TIMER_TYPE_MEM, &t->evt); |
| 1182 | |
| 1183 | if (arch_timer_mem_use_virtual) |
| 1184 | func = arch_timer_handler_virt_mem; |
| 1185 | else |
| 1186 | func = arch_timer_handler_phys_mem; |
| 1187 | |
| 1188 | ret = request_irq(irq, func, IRQF_TIMER, "arch_mem_timer", &t->evt); |
| 1189 | if (ret) { |
| 1190 | pr_err("Failed to request mem timer irq\n"); |
| 1191 | kfree(t); |
| 1192 | } |
| 1193 | |
| 1194 | return ret; |
| 1195 | } |
| 1196 | |
| 1197 | static const struct of_device_id arch_timer_of_match[] __initconst = { |
| 1198 | { .compatible = "arm,armv7-timer", }, |
| 1199 | { .compatible = "arm,armv8-timer", }, |
| 1200 | {}, |
| 1201 | }; |
| 1202 | |
| 1203 | static const struct of_device_id arch_timer_mem_of_match[] __initconst = { |
| 1204 | { .compatible = "arm,armv7-timer-mem", }, |
| 1205 | {}, |
| 1206 | }; |
| 1207 | |
| 1208 | static bool __init arch_timer_needs_of_probing(void) |
| 1209 | { |
| 1210 | struct device_node *dn; |
| 1211 | bool needs_probing = false; |
| 1212 | unsigned int mask = ARCH_TIMER_TYPE_CP15 | ARCH_TIMER_TYPE_MEM; |
| 1213 | |
| 1214 | /* We have two timers, and both device-tree nodes are probed. */ |
| 1215 | if ((arch_timers_present & mask) == mask) |
| 1216 | return false; |
| 1217 | |
| 1218 | /* |
| 1219 | * Only one type of timer is probed, |
| 1220 | * check if we have another type of timer node in device-tree. |
| 1221 | */ |
| 1222 | if (arch_timers_present & ARCH_TIMER_TYPE_CP15) |
| 1223 | dn = of_find_matching_node(NULL, arch_timer_mem_of_match); |
| 1224 | else |
| 1225 | dn = of_find_matching_node(NULL, arch_timer_of_match); |
| 1226 | |
| 1227 | if (dn && of_device_is_available(dn)) |
| 1228 | needs_probing = true; |
| 1229 | |
| 1230 | of_node_put(dn); |
| 1231 | |
| 1232 | return needs_probing; |
| 1233 | } |
| 1234 | |
| 1235 | static int __init arch_timer_common_init(void) |
| 1236 | { |
| 1237 | arch_timer_banner(arch_timers_present); |
| 1238 | arch_counter_register(arch_timers_present); |
| 1239 | return arch_timer_arch_init(); |
| 1240 | } |
| 1241 | |
| 1242 | /** |
| 1243 | * arch_timer_select_ppi() - Select suitable PPI for the current system. |
| 1244 | * |
| 1245 | * If HYP mode is available, we know that the physical timer |
| 1246 | * has been configured to be accessible from PL1. Use it, so |
| 1247 | * that a guest can use the virtual timer instead. |
| 1248 | * |
| 1249 | * On ARMv8.1 with VH extensions, the kernel runs in HYP. VHE |
| 1250 | * accesses to CNTP_*_EL1 registers are silently redirected to |
| 1251 | * their CNTHP_*_EL2 counterparts, and use a different PPI |
| 1252 | * number. |
| 1253 | * |
| 1254 | * If no interrupt provided for virtual timer, we'll have to |
| 1255 | * stick to the physical timer. It'd better be accessible... |
| 1256 | * For arm64 we never use the secure interrupt. |
| 1257 | * |
| 1258 | * Return: a suitable PPI type for the current system. |
| 1259 | */ |
| 1260 | static enum arch_timer_ppi_nr __init arch_timer_select_ppi(void) |
| 1261 | { |
| 1262 | if (is_kernel_in_hyp_mode()) |
| 1263 | return ARCH_TIMER_HYP_PPI; |
| 1264 | |
| 1265 | if (!is_hyp_mode_available() && arch_timer_ppi[ARCH_TIMER_VIRT_PPI]) |
| 1266 | return ARCH_TIMER_VIRT_PPI; |
| 1267 | |
| 1268 | if (IS_ENABLED(CONFIG_ARM64)) |
| 1269 | return ARCH_TIMER_PHYS_NONSECURE_PPI; |
| 1270 | |
| 1271 | return ARCH_TIMER_PHYS_SECURE_PPI; |
| 1272 | } |
| 1273 | |
| 1274 | static void __init arch_timer_populate_kvm_info(void) |
| 1275 | { |
| 1276 | arch_timer_kvm_info.virtual_irq = arch_timer_ppi[ARCH_TIMER_VIRT_PPI]; |
| 1277 | if (is_kernel_in_hyp_mode()) |
| 1278 | arch_timer_kvm_info.physical_irq = arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]; |
| 1279 | } |
| 1280 | |
| 1281 | static int __init arch_timer_of_init(struct device_node *np) |
| 1282 | { |
| 1283 | int i, ret; |
| 1284 | u32 rate; |
| 1285 | |
| 1286 | if (arch_timers_present & ARCH_TIMER_TYPE_CP15) { |
| 1287 | pr_warn("multiple nodes in dt, skipping\n"); |
| 1288 | return 0; |
| 1289 | } |
| 1290 | |
| 1291 | arch_timers_present |= ARCH_TIMER_TYPE_CP15; |
| 1292 | for (i = ARCH_TIMER_PHYS_SECURE_PPI; i < ARCH_TIMER_MAX_TIMER_PPI; i++) |
| 1293 | arch_timer_ppi[i] = irq_of_parse_and_map(np, i); |
| 1294 | |
| 1295 | arch_timer_populate_kvm_info(); |
| 1296 | |
| 1297 | rate = arch_timer_get_cntfrq(); |
| 1298 | arch_timer_of_configure_rate(rate, np); |
| 1299 | |
| 1300 | arch_timer_c3stop = !of_property_read_bool(np, "always-on"); |
| 1301 | |
| 1302 | /* Check for globally applicable workarounds */ |
| 1303 | arch_timer_check_ool_workaround(ate_match_dt, np); |
| 1304 | |
| 1305 | /* |
| 1306 | * If we cannot rely on firmware initializing the timer registers then |
| 1307 | * we should use the physical timers instead. |
| 1308 | */ |
| 1309 | if (IS_ENABLED(CONFIG_ARM) && |
| 1310 | of_property_read_bool(np, "arm,cpu-registers-not-fw-configured")) |
| 1311 | arch_timer_uses_ppi = ARCH_TIMER_PHYS_SECURE_PPI; |
| 1312 | else |
| 1313 | arch_timer_uses_ppi = arch_timer_select_ppi(); |
| 1314 | |
| 1315 | if (!arch_timer_ppi[arch_timer_uses_ppi]) { |
| 1316 | pr_err("No interrupt available, giving up\n"); |
| 1317 | return -EINVAL; |
| 1318 | } |
| 1319 | |
| 1320 | /* On some systems, the counter stops ticking when in suspend. */ |
| 1321 | arch_counter_suspend_stop = of_property_read_bool(np, |
| 1322 | "arm,no-tick-in-suspend"); |
| 1323 | |
| 1324 | ret = arch_timer_register(); |
| 1325 | if (ret) |
| 1326 | return ret; |
| 1327 | |
| 1328 | if (arch_timer_needs_of_probing()) |
| 1329 | return 0; |
| 1330 | |
| 1331 | return arch_timer_common_init(); |
| 1332 | } |
| 1333 | TIMER_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_of_init); |
| 1334 | TIMER_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_of_init); |
| 1335 | |
| 1336 | static u32 __init |
| 1337 | arch_timer_mem_frame_get_cntfrq(struct arch_timer_mem_frame *frame) |
| 1338 | { |
| 1339 | void __iomem *base; |
| 1340 | u32 rate; |
| 1341 | |
| 1342 | base = ioremap(frame->cntbase, frame->size); |
| 1343 | if (!base) { |
| 1344 | pr_err("Unable to map frame @ %pa\n", &frame->cntbase); |
| 1345 | return 0; |
| 1346 | } |
| 1347 | |
| 1348 | rate = readl_relaxed(base + CNTFRQ); |
| 1349 | |
| 1350 | iounmap(base); |
| 1351 | |
| 1352 | return rate; |
| 1353 | } |
| 1354 | |
| 1355 | static struct arch_timer_mem_frame * __init |
| 1356 | arch_timer_mem_find_best_frame(struct arch_timer_mem *timer_mem) |
| 1357 | { |
| 1358 | struct arch_timer_mem_frame *frame, *best_frame = NULL; |
| 1359 | void __iomem *cntctlbase; |
| 1360 | u32 cnttidr; |
| 1361 | int i; |
| 1362 | |
| 1363 | cntctlbase = ioremap(timer_mem->cntctlbase, timer_mem->size); |
| 1364 | if (!cntctlbase) { |
| 1365 | pr_err("Can't map CNTCTLBase @ %pa\n", |
| 1366 | &timer_mem->cntctlbase); |
| 1367 | return NULL; |
| 1368 | } |
| 1369 | |
| 1370 | cnttidr = readl_relaxed(cntctlbase + CNTTIDR); |
| 1371 | |
| 1372 | /* |
| 1373 | * Try to find a virtual capable frame. Otherwise fall back to a |
| 1374 | * physical capable frame. |
| 1375 | */ |
| 1376 | for (i = 0; i < ARCH_TIMER_MEM_MAX_FRAMES; i++) { |
| 1377 | u32 cntacr = CNTACR_RFRQ | CNTACR_RWPT | CNTACR_RPCT | |
| 1378 | CNTACR_RWVT | CNTACR_RVOFF | CNTACR_RVCT; |
| 1379 | |
| 1380 | frame = &timer_mem->frame[i]; |
| 1381 | if (!frame->valid) |
| 1382 | continue; |
| 1383 | |
| 1384 | /* Try enabling everything, and see what sticks */ |
| 1385 | writel_relaxed(cntacr, cntctlbase + CNTACR(i)); |
| 1386 | cntacr = readl_relaxed(cntctlbase + CNTACR(i)); |
| 1387 | |
| 1388 | if ((cnttidr & CNTTIDR_VIRT(i)) && |
| 1389 | !(~cntacr & (CNTACR_RWVT | CNTACR_RVCT))) { |
| 1390 | best_frame = frame; |
| 1391 | arch_timer_mem_use_virtual = true; |
| 1392 | break; |
| 1393 | } |
| 1394 | |
| 1395 | if (~cntacr & (CNTACR_RWPT | CNTACR_RPCT)) |
| 1396 | continue; |
| 1397 | |
| 1398 | best_frame = frame; |
| 1399 | } |
| 1400 | |
| 1401 | iounmap(cntctlbase); |
| 1402 | |
| 1403 | return best_frame; |
| 1404 | } |
| 1405 | |
| 1406 | static int __init |
| 1407 | arch_timer_mem_frame_register(struct arch_timer_mem_frame *frame) |
| 1408 | { |
| 1409 | void __iomem *base; |
| 1410 | int ret, irq = 0; |
| 1411 | |
| 1412 | if (arch_timer_mem_use_virtual) |
| 1413 | irq = frame->virt_irq; |
| 1414 | else |
| 1415 | irq = frame->phys_irq; |
| 1416 | |
| 1417 | if (!irq) { |
| 1418 | pr_err("Frame missing %s irq.\n", |
| 1419 | arch_timer_mem_use_virtual ? "virt" : "phys"); |
| 1420 | return -EINVAL; |
| 1421 | } |
| 1422 | |
| 1423 | if (!request_mem_region(frame->cntbase, frame->size, |
| 1424 | "arch_mem_timer")) |
| 1425 | return -EBUSY; |
| 1426 | |
| 1427 | base = ioremap(frame->cntbase, frame->size); |
| 1428 | if (!base) { |
| 1429 | pr_err("Can't map frame's registers\n"); |
| 1430 | return -ENXIO; |
| 1431 | } |
| 1432 | |
| 1433 | ret = arch_timer_mem_register(base, irq); |
| 1434 | if (ret) { |
| 1435 | iounmap(base); |
| 1436 | return ret; |
| 1437 | } |
| 1438 | |
| 1439 | arch_counter_base = base; |
| 1440 | arch_timers_present |= ARCH_TIMER_TYPE_MEM; |
| 1441 | |
| 1442 | return 0; |
| 1443 | } |
| 1444 | |
| 1445 | static int __init arch_timer_mem_of_init(struct device_node *np) |
| 1446 | { |
| 1447 | struct arch_timer_mem *timer_mem; |
| 1448 | struct arch_timer_mem_frame *frame; |
| 1449 | struct device_node *frame_node; |
| 1450 | struct resource res; |
| 1451 | int ret = -EINVAL; |
| 1452 | u32 rate; |
| 1453 | |
| 1454 | timer_mem = kzalloc(sizeof(*timer_mem), GFP_KERNEL); |
| 1455 | if (!timer_mem) |
| 1456 | return -ENOMEM; |
| 1457 | |
| 1458 | if (of_address_to_resource(np, 0, &res)) |
| 1459 | goto out; |
| 1460 | timer_mem->cntctlbase = res.start; |
| 1461 | timer_mem->size = resource_size(&res); |
| 1462 | |
| 1463 | for_each_available_child_of_node(np, frame_node) { |
| 1464 | u32 n; |
| 1465 | struct arch_timer_mem_frame *frame; |
| 1466 | |
| 1467 | if (of_property_read_u32(frame_node, "frame-number", &n)) { |
| 1468 | pr_err(FW_BUG "Missing frame-number.\n"); |
| 1469 | of_node_put(frame_node); |
| 1470 | goto out; |
| 1471 | } |
| 1472 | if (n >= ARCH_TIMER_MEM_MAX_FRAMES) { |
| 1473 | pr_err(FW_BUG "Wrong frame-number, only 0-%u are permitted.\n", |
| 1474 | ARCH_TIMER_MEM_MAX_FRAMES - 1); |
| 1475 | of_node_put(frame_node); |
| 1476 | goto out; |
| 1477 | } |
| 1478 | frame = &timer_mem->frame[n]; |
| 1479 | |
| 1480 | if (frame->valid) { |
| 1481 | pr_err(FW_BUG "Duplicated frame-number.\n"); |
| 1482 | of_node_put(frame_node); |
| 1483 | goto out; |
| 1484 | } |
| 1485 | |
| 1486 | if (of_address_to_resource(frame_node, 0, &res)) { |
| 1487 | of_node_put(frame_node); |
| 1488 | goto out; |
| 1489 | } |
| 1490 | frame->cntbase = res.start; |
| 1491 | frame->size = resource_size(&res); |
| 1492 | |
| 1493 | frame->virt_irq = irq_of_parse_and_map(frame_node, |
| 1494 | ARCH_TIMER_VIRT_SPI); |
| 1495 | frame->phys_irq = irq_of_parse_and_map(frame_node, |
| 1496 | ARCH_TIMER_PHYS_SPI); |
| 1497 | |
| 1498 | frame->valid = true; |
| 1499 | } |
| 1500 | |
| 1501 | frame = arch_timer_mem_find_best_frame(timer_mem); |
| 1502 | if (!frame) { |
| 1503 | pr_err("Unable to find a suitable frame in timer @ %pa\n", |
| 1504 | &timer_mem->cntctlbase); |
| 1505 | ret = -EINVAL; |
| 1506 | goto out; |
| 1507 | } |
| 1508 | |
| 1509 | rate = arch_timer_mem_frame_get_cntfrq(frame); |
| 1510 | arch_timer_of_configure_rate(rate, np); |
| 1511 | |
| 1512 | ret = arch_timer_mem_frame_register(frame); |
| 1513 | if (!ret && !arch_timer_needs_of_probing()) |
| 1514 | ret = arch_timer_common_init(); |
| 1515 | out: |
| 1516 | kfree(timer_mem); |
| 1517 | return ret; |
| 1518 | } |
| 1519 | TIMER_OF_DECLARE(armv7_arch_timer_mem, "arm,armv7-timer-mem", |
| 1520 | arch_timer_mem_of_init); |
| 1521 | |
| 1522 | #ifdef CONFIG_ACPI_GTDT |
| 1523 | static int __init |
| 1524 | arch_timer_mem_verify_cntfrq(struct arch_timer_mem *timer_mem) |
| 1525 | { |
| 1526 | struct arch_timer_mem_frame *frame; |
| 1527 | u32 rate; |
| 1528 | int i; |
| 1529 | |
| 1530 | for (i = 0; i < ARCH_TIMER_MEM_MAX_FRAMES; i++) { |
| 1531 | frame = &timer_mem->frame[i]; |
| 1532 | |
| 1533 | if (!frame->valid) |
| 1534 | continue; |
| 1535 | |
| 1536 | rate = arch_timer_mem_frame_get_cntfrq(frame); |
| 1537 | if (rate == arch_timer_rate) |
| 1538 | continue; |
| 1539 | |
| 1540 | pr_err(FW_BUG "CNTFRQ mismatch: frame @ %pa: (0x%08lx), CPU: (0x%08lx)\n", |
| 1541 | &frame->cntbase, |
| 1542 | (unsigned long)rate, (unsigned long)arch_timer_rate); |
| 1543 | |
| 1544 | return -EINVAL; |
| 1545 | } |
| 1546 | |
| 1547 | return 0; |
| 1548 | } |
| 1549 | |
| 1550 | static int __init arch_timer_mem_acpi_init(int platform_timer_count) |
| 1551 | { |
| 1552 | struct arch_timer_mem *timers, *timer; |
| 1553 | struct arch_timer_mem_frame *frame, *best_frame = NULL; |
| 1554 | int timer_count, i, ret = 0; |
| 1555 | |
| 1556 | timers = kcalloc(platform_timer_count, sizeof(*timers), |
| 1557 | GFP_KERNEL); |
| 1558 | if (!timers) |
| 1559 | return -ENOMEM; |
| 1560 | |
| 1561 | ret = acpi_arch_timer_mem_init(timers, &timer_count); |
| 1562 | if (ret || !timer_count) |
| 1563 | goto out; |
| 1564 | |
| 1565 | /* |
| 1566 | * While unlikely, it's theoretically possible that none of the frames |
| 1567 | * in a timer expose the combination of feature we want. |
| 1568 | */ |
| 1569 | for (i = 0; i < timer_count; i++) { |
| 1570 | timer = &timers[i]; |
| 1571 | |
| 1572 | frame = arch_timer_mem_find_best_frame(timer); |
| 1573 | if (!best_frame) |
| 1574 | best_frame = frame; |
| 1575 | |
| 1576 | ret = arch_timer_mem_verify_cntfrq(timer); |
| 1577 | if (ret) { |
| 1578 | pr_err("Disabling MMIO timers due to CNTFRQ mismatch\n"); |
| 1579 | goto out; |
| 1580 | } |
| 1581 | |
| 1582 | if (!best_frame) /* implies !frame */ |
| 1583 | /* |
| 1584 | * Only complain about missing suitable frames if we |
| 1585 | * haven't already found one in a previous iteration. |
| 1586 | */ |
| 1587 | pr_err("Unable to find a suitable frame in timer @ %pa\n", |
| 1588 | &timer->cntctlbase); |
| 1589 | } |
| 1590 | |
| 1591 | if (best_frame) |
| 1592 | ret = arch_timer_mem_frame_register(best_frame); |
| 1593 | out: |
| 1594 | kfree(timers); |
| 1595 | return ret; |
| 1596 | } |
| 1597 | |
| 1598 | /* Initialize per-processor generic timer and memory-mapped timer(if present) */ |
| 1599 | static int __init arch_timer_acpi_init(struct acpi_table_header *table) |
| 1600 | { |
| 1601 | int ret, platform_timer_count; |
| 1602 | |
| 1603 | if (arch_timers_present & ARCH_TIMER_TYPE_CP15) { |
| 1604 | pr_warn("already initialized, skipping\n"); |
| 1605 | return -EINVAL; |
| 1606 | } |
| 1607 | |
| 1608 | arch_timers_present |= ARCH_TIMER_TYPE_CP15; |
| 1609 | |
| 1610 | ret = acpi_gtdt_init(table, &platform_timer_count); |
| 1611 | if (ret) |
| 1612 | return ret; |
| 1613 | |
| 1614 | arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI] = |
| 1615 | acpi_gtdt_map_ppi(ARCH_TIMER_PHYS_NONSECURE_PPI); |
| 1616 | |
| 1617 | arch_timer_ppi[ARCH_TIMER_VIRT_PPI] = |
| 1618 | acpi_gtdt_map_ppi(ARCH_TIMER_VIRT_PPI); |
| 1619 | |
| 1620 | arch_timer_ppi[ARCH_TIMER_HYP_PPI] = |
| 1621 | acpi_gtdt_map_ppi(ARCH_TIMER_HYP_PPI); |
| 1622 | |
| 1623 | arch_timer_populate_kvm_info(); |
| 1624 | |
| 1625 | /* |
| 1626 | * When probing via ACPI, we have no mechanism to override the sysreg |
| 1627 | * CNTFRQ value. This *must* be correct. |
| 1628 | */ |
| 1629 | arch_timer_rate = arch_timer_get_cntfrq(); |
| 1630 | ret = validate_timer_rate(); |
| 1631 | if (ret) { |
| 1632 | pr_err(FW_BUG "frequency not available.\n"); |
| 1633 | return ret; |
| 1634 | } |
| 1635 | |
| 1636 | arch_timer_uses_ppi = arch_timer_select_ppi(); |
| 1637 | if (!arch_timer_ppi[arch_timer_uses_ppi]) { |
| 1638 | pr_err("No interrupt available, giving up\n"); |
| 1639 | return -EINVAL; |
| 1640 | } |
| 1641 | |
| 1642 | /* Always-on capability */ |
| 1643 | arch_timer_c3stop = acpi_gtdt_c3stop(arch_timer_uses_ppi); |
| 1644 | |
| 1645 | /* Check for globally applicable workarounds */ |
| 1646 | arch_timer_check_ool_workaround(ate_match_acpi_oem_info, table); |
| 1647 | |
| 1648 | ret = arch_timer_register(); |
| 1649 | if (ret) |
| 1650 | return ret; |
| 1651 | |
| 1652 | if (platform_timer_count && |
| 1653 | arch_timer_mem_acpi_init(platform_timer_count)) |
| 1654 | pr_err("Failed to initialize memory-mapped timer.\n"); |
| 1655 | |
| 1656 | return arch_timer_common_init(); |
| 1657 | } |
| 1658 | TIMER_ACPI_DECLARE(arch_timer, ACPI_SIG_GTDT, arch_timer_acpi_init); |
| 1659 | #endif |