1 /* $OpenBSD: acpitimer.c,v 1.17 2023/02/04 19:19:37 cheloha Exp $ */ 2 /* 3 * Copyright (c) 2005 Thorsten Lockert <tholo@sigmasoft.com> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #include <sys/param.h> 19 #include <sys/systm.h> 20 #include <sys/device.h> 21 #include <sys/stdint.h> 22 #include <sys/timetc.h> 23 24 #include <machine/bus.h> 25 #include <machine/cpu.h> 26 27 #include <dev/acpi/acpireg.h> 28 #include <dev/acpi/acpivar.h> 29 30 struct acpitimer_softc { 31 struct device sc_dev; 32 33 bus_space_tag_t sc_iot; 34 bus_space_handle_t sc_ioh; 35 }; 36 37 int acpitimermatch(struct device *, void *, void *); 38 void acpitimerattach(struct device *, struct device *, void *); 39 void acpitimer_delay(int); 40 u_int acpi_get_timecount(struct timecounter *tc); 41 uint32_t acpitimer_read(struct acpitimer_softc *); 42 43 static struct timecounter acpi_timecounter = { 44 .tc_get_timecount = acpi_get_timecount, 45 .tc_counter_mask = 0x00ffffff, /* 24 bits */ 46 .tc_frequency = ACPI_FREQUENCY, 47 .tc_name = 0, 48 .tc_quality = 1000, 49 .tc_priv = NULL, 50 .tc_user = 0, 51 }; 52 53 const struct cfattach acpitimer_ca = { 54 sizeof(struct acpitimer_softc), acpitimermatch, acpitimerattach 55 }; 56 57 struct cfdriver acpitimer_cd = { 58 NULL, "acpitimer", DV_DULL 59 }; 60 61 int 62 acpitimermatch(struct device *parent, void *match, void *aux) 63 { 64 struct acpi_attach_args *aa = aux; 65 struct cfdata *cf = match; 66 67 /* sanity */ 68 if (aa->aaa_name == NULL || 69 strcmp(aa->aaa_name, cf->cf_driver->cd_name) != 0 || 70 aa->aaa_table != NULL) 71 return (0); 72 73 return (1); 74 } 75 76 void 77 acpitimerattach(struct device *parent, struct device *self, void *aux) 78 { 79 struct acpitimer_softc *sc = (struct acpitimer_softc *) self; 80 struct acpi_softc *psc = (struct acpi_softc *) parent; 81 int rc; 82 83 if (psc->sc_fadt->hdr_revision >= 3 && 84 psc->sc_fadt->x_pm_tmr_blk.address != 0) 85 rc = acpi_map_address(psc, &psc->sc_fadt->x_pm_tmr_blk, 0, 86 psc->sc_fadt->pm_tmr_len, &sc->sc_ioh, &sc->sc_iot); 87 else 88 rc = acpi_map_address(psc, NULL, psc->sc_fadt->pm_tmr_blk, 89 psc->sc_fadt->pm_tmr_len, &sc->sc_ioh, &sc->sc_iot); 90 if (rc) { 91 printf(": can't map i/o space\n"); 92 return; 93 } 94 95 printf(": %d Hz, %d bits\n", ACPI_FREQUENCY, 96 psc->sc_fadt->flags & FADT_TMR_VAL_EXT ? 32 : 24); 97 98 if (psc->sc_fadt->flags & FADT_TMR_VAL_EXT) 99 acpi_timecounter.tc_counter_mask = 0xffffffffU; 100 acpi_timecounter.tc_priv = sc; 101 acpi_timecounter.tc_name = sc->sc_dev.dv_xname; 102 tc_init(&acpi_timecounter); 103 104 delay_init(acpitimer_delay, 1000); 105 106 #if defined(__amd64__) 107 extern void cpu_recalibrate_tsc(struct timecounter *); 108 cpu_recalibrate_tsc(&acpi_timecounter); 109 #endif 110 } 111 112 void 113 acpitimer_delay(int usecs) 114 { 115 uint64_t count = 0, cycles; 116 struct acpitimer_softc *sc = acpi_timecounter.tc_priv; 117 uint32_t mask = acpi_timecounter.tc_counter_mask; 118 uint32_t val1, val2; 119 120 val2 = acpitimer_read(sc); 121 cycles = usecs * acpi_timecounter.tc_frequency / 1000000; 122 while (count < cycles) { 123 CPU_BUSY_CYCLE(); 124 val1 = val2; 125 val2 = acpitimer_read(sc); 126 count += (val2 - val1) & mask; 127 } 128 } 129 130 u_int 131 acpi_get_timecount(struct timecounter *tc) 132 { 133 return acpitimer_read(tc->tc_priv); 134 } 135 136 uint32_t 137 acpitimer_read(struct acpitimer_softc *sc) 138 { 139 uint32_t u1, u2, u3; 140 141 u2 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, 0); 142 u3 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, 0); 143 do { 144 u1 = u2; 145 u2 = u3; 146 u3 = bus_space_read_4(sc->sc_iot, sc->sc_ioh, 0); 147 } while (u1 > u2 || u2 > u3); 148 149 return (u2); 150 } 151