/*- * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2008 Poul-Henning Kamp * Copyright (c) 2010 Alexander Motin * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include "opt_acpi.h" #include "opt_isa.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef DEV_ISA #include #include #endif #include #include "clock_if.h" #ifdef DEV_ACPI #include #include #include #include #endif /* tunable to detect a power loss of the rtc */ static bool atrtc_power_lost = false; SYSCTL_BOOL(_machdep, OID_AUTO, atrtc_power_lost, CTLFLAG_RD, &atrtc_power_lost, false, "RTC lost power on last power cycle (probably caused by an empty cmos battery)"); /* * atrtc_lock protects low-level access to individual hardware registers. * atrtc_time_lock protects the entire sequence of accessing multiple registers * to read or write the date and time. */ static struct mtx atrtc_lock; MTX_SYSINIT(atrtc_lock_init, &atrtc_lock, "atrtc", MTX_SPIN); /* Force RTC enabled/disabled. */ static int atrtc_enabled = -1; TUNABLE_INT("hw.atrtc.enabled", &atrtc_enabled); struct mtx atrtc_time_lock; MTX_SYSINIT(atrtc_time_lock_init, &atrtc_time_lock, "atrtc_time", MTX_DEF); int atrtcclock_disable = 0; static int rtc_century = 0; static int rtc_reg = -1; static u_char rtc_statusa = RTCSA_DIVIDER | RTCSA_NOPROF; static u_char rtc_statusb = RTCSB_24HR; #ifdef DEV_ACPI #define _COMPONENT ACPI_TIMER ACPI_MODULE_NAME("ATRTC") #endif /* * RTC support routines */ static inline u_char rtcin_locked(int reg) { if (rtc_reg != reg) { inb(0x84); outb(IO_RTC, reg); rtc_reg = reg; inb(0x84); } return (inb(IO_RTC + 1)); } static inline void rtcout_locked(int reg, u_char val) { if (rtc_reg != reg) { inb(0x84); outb(IO_RTC, reg); rtc_reg = reg; inb(0x84); } outb(IO_RTC + 1, val); inb(0x84); } int rtcin(int reg) { u_char val; mtx_lock_spin(&atrtc_lock); val = rtcin_locked(reg); mtx_unlock_spin(&atrtc_lock); return (val); } void writertc(int reg, u_char val) { mtx_lock_spin(&atrtc_lock); rtcout_locked(reg, val); mtx_unlock_spin(&atrtc_lock); } static void atrtc_start(void) { mtx_lock_spin(&atrtc_lock); rtcout_locked(RTC_STATUSA, rtc_statusa); rtcout_locked(RTC_STATUSB, RTCSB_24HR); mtx_unlock_spin(&atrtc_lock); } static void atrtc_rate(unsigned rate) { rtc_statusa = RTCSA_DIVIDER | rate; writertc(RTC_STATUSA, rtc_statusa); } static void atrtc_enable_intr(void) { rtc_statusb |= RTCSB_PINTR; mtx_lock_spin(&atrtc_lock); rtcout_locked(RTC_STATUSB, rtc_statusb); rtcin_locked(RTC_INTR); mtx_unlock_spin(&atrtc_lock); } static void atrtc_disable_intr(void) { rtc_statusb &= ~RTCSB_PINTR; mtx_lock_spin(&atrtc_lock); rtcout_locked(RTC_STATUSB, rtc_statusb); rtcin_locked(RTC_INTR); mtx_unlock_spin(&atrtc_lock); } void atrtc_restore(void) { /* Restore all of the RTC's "status" (actually, control) registers. */ mtx_lock_spin(&atrtc_lock); rtcin_locked(RTC_STATUSA); /* dummy to get rtc_reg set */ rtcout_locked(RTC_STATUSB, RTCSB_24HR); rtcout_locked(RTC_STATUSA, rtc_statusa); rtcout_locked(RTC_STATUSB, rtc_statusb); rtcin_locked(RTC_INTR); mtx_unlock_spin(&atrtc_lock); } /********************************************************************** * RTC driver for subr_rtc */ struct atrtc_softc { int port_rid, intr_rid; struct resource *port_res; struct resource *intr_res; void *intr_handler; struct eventtimer et; #ifdef DEV_ACPI ACPI_HANDLE acpi_handle; #endif }; static int rtc_start(struct eventtimer *et, sbintime_t first, sbintime_t period) { atrtc_rate(max(fls(period + (period >> 1)) - 17, 1)); atrtc_enable_intr(); return (0); } static int rtc_stop(struct eventtimer *et) { atrtc_disable_intr(); return (0); } /* * This routine receives statistical clock interrupts from the RTC. * As explained above, these occur at 128 interrupts per second. * When profiling, we receive interrupts at a rate of 1024 Hz. * * This does not actually add as much overhead as it sounds, because * when the statistical clock is active, the hardclock driver no longer * needs to keep (inaccurate) statistics on its own. This decouples * statistics gathering from scheduling interrupts. * * The RTC chip requires that we read status register C (RTC_INTR) * to acknowledge an interrupt, before it will generate the next one. * Under high interrupt load, rtcintr() can be indefinitely delayed and * the clock can tick immediately after the read from RTC_INTR. In this * case, the mc146818A interrupt signal will not drop for long enough * to register with the 8259 PIC. If an interrupt is missed, the stat * clock will halt, considerably degrading system performance. This is * why we use 'while' rather than a more straightforward 'if' below. * Stat clock ticks can still be lost, causing minor loss of accuracy * in the statistics, but the stat clock will no longer stop. */ static int rtc_intr(void *arg) { struct atrtc_softc *sc = (struct atrtc_softc *)arg; int flag = 0; while (rtcin(RTC_INTR) & RTCIR_PERIOD) { flag = 1; if (sc->et.et_active) sc->et.et_event_cb(&sc->et, sc->et.et_arg); } return(flag ? FILTER_HANDLED : FILTER_STRAY); } #ifdef DEV_ACPI /* * ACPI RTC CMOS address space handler */ #define ATRTC_LAST_REG 0x40 static void rtcin_region(int reg, void *buf, int len) { u_char *ptr = buf; /* Drop lock after each IO as intr and settime have greater priority */ while (len-- > 0) *ptr++ = rtcin(reg++) & 0xff; } static void rtcout_region(int reg, const void *buf, int len) { const u_char *ptr = buf; while (len-- > 0) writertc(reg++, *ptr++); } static bool atrtc_check_cmos_access(bool is_read, ACPI_PHYSICAL_ADDRESS addr, UINT32 len) { /* Block address space wrapping on out-of-bound access */ if (addr >= ATRTC_LAST_REG || addr + len > ATRTC_LAST_REG) return (false); if (is_read) { /* Reading 0x0C will muck with interrupts */ if (addr <= RTC_INTR && addr + len > RTC_INTR) return (false); } else { /* * Allow single-byte writes to alarm registers and * multi-byte writes to addr >= 0x30, else deny. */ if (!((len == 1 && (addr == RTC_SECALRM || addr == RTC_MINALRM || addr == RTC_HRSALRM)) || addr >= 0x30)) return (false); } return (true); } static ACPI_STATUS atrtc_acpi_cmos_handler(UINT32 func, ACPI_PHYSICAL_ADDRESS addr, UINT32 bitwidth, UINT64 *value, void *context, void *region_context) { device_t dev = context; UINT32 bytewidth = howmany(bitwidth, 8); bool is_read = func == ACPI_READ; /* ACPICA is very verbose on CMOS handler failures, so we, too */ #define CMOS_HANDLER_ERR(fmt, ...) \ device_printf(dev, "ACPI [SystemCMOS] handler: " fmt, ##__VA_ARGS__) ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); if (value == NULL) { CMOS_HANDLER_ERR("NULL parameter\n"); return (AE_BAD_PARAMETER); } if (bitwidth == 0 || (bitwidth & 0x07) != 0) { CMOS_HANDLER_ERR("Invalid bitwidth: %u\n", bitwidth); return (AE_BAD_PARAMETER); } if (!atrtc_check_cmos_access(is_read, addr, bytewidth)) { CMOS_HANDLER_ERR("%s access rejected: addr=%#04jx, len=%u\n", is_read ? "Read" : "Write", (uintmax_t)addr, bytewidth); return (AE_BAD_PARAMETER); } switch (func) { case ACPI_READ: rtcin_region(addr, value, bytewidth); break; case ACPI_WRITE: rtcout_region(addr, value, bytewidth); break; default: CMOS_HANDLER_ERR("Invalid function: %u\n", func); return (AE_BAD_PARAMETER); } ACPI_VPRINT(dev, acpi_device_get_parent_softc(dev), "ACPI RTC CMOS %s access: addr=%#04x, len=%u, val=%*D\n", is_read ? "read" : "write", (unsigned)addr, bytewidth, bytewidth, value, " "); return (AE_OK); } static int atrtc_reg_acpi_cmos_handler(device_t dev) { struct atrtc_softc *sc = device_get_softc(dev); ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__); /* Don't handle address space events if driver is disabled. */ if (acpi_disabled("atrtc")) return (ENXIO); sc->acpi_handle = acpi_get_handle(dev); if (sc->acpi_handle == NULL || ACPI_FAILURE(AcpiInstallAddressSpaceHandler(sc->acpi_handle, ACPI_ADR_SPACE_CMOS, atrtc_acpi_cmos_handler, NULL, dev))) { sc->acpi_handle = NULL; device_printf(dev, "Can't register ACPI CMOS address space handler\n"); return (ENXIO); } return (0); } static int atrtc_unreg_acpi_cmos_handler(device_t dev) { struct atrtc_softc *sc = device_get_softc(dev); ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__); if (sc->acpi_handle != NULL) AcpiRemoveAddressSpaceHandler(sc->acpi_handle, ACPI_ADR_SPACE_CMOS, atrtc_acpi_cmos_handler); return (0); } #endif /* DEV_ACPI */ /* * Attach to the ISA PnP descriptors for the timer and realtime clock. */ static struct isa_pnp_id atrtc_ids[] = { { 0x000bd041 /* PNP0B00 */, "AT realtime clock" }, { 0 } }; static bool atrtc_acpi_disabled(void) { #ifdef DEV_ACPI uint16_t flags; if (!acpi_get_fadt_bootflags(&flags)) return (false); return ((flags & ACPI_FADT_NO_CMOS_RTC) != 0); #else return (false); #endif } static int rtc_acpi_century_get(void) { #ifdef DEV_ACPI ACPI_TABLE_FADT *fadt; vm_paddr_t physaddr; int century; physaddr = acpi_find_table(ACPI_SIG_FADT); if (physaddr == 0) return (0); fadt = acpi_map_table(physaddr, ACPI_SIG_FADT); if (fadt == NULL) return (0); century = fadt->Century; acpi_unmap_table(fadt); return (century); #else return (0); #endif } static int atrtc_probe(device_t dev) { int result; if ((atrtc_enabled == -1 && atrtc_acpi_disabled()) || (atrtc_enabled == 0)) return (ENXIO); result = ISA_PNP_PROBE(device_get_parent(dev), dev, atrtc_ids); /* ENOENT means no PnP-ID, device is hinted. */ if (result == ENOENT) { device_set_desc(dev, "AT realtime clock"); return (BUS_PROBE_LOW_PRIORITY); } rtc_century = rtc_acpi_century_get(); return (result); } static int atrtc_attach(device_t dev) { struct atrtc_softc *sc; rman_res_t s; int i; sc = device_get_softc(dev); sc->port_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->port_rid, IO_RTC, IO_RTC + 1, 2, RF_ACTIVE); if (sc->port_res == NULL) device_printf(dev, "Warning: Couldn't map I/O.\n"); atrtc_start(); clock_register(dev, 1000000); bzero(&sc->et, sizeof(struct eventtimer)); if (!atrtcclock_disable && (resource_int_value(device_get_name(dev), device_get_unit(dev), "clock", &i) != 0 || i != 0)) { sc->intr_rid = 0; while (bus_get_resource(dev, SYS_RES_IRQ, sc->intr_rid, &s, NULL) == 0 && s != 8) sc->intr_rid++; sc->intr_res = bus_alloc_resource(dev, SYS_RES_IRQ, &sc->intr_rid, 8, 8, 1, RF_ACTIVE); if (sc->intr_res == NULL) { device_printf(dev, "Can't map interrupt.\n"); return (0); } else if ((bus_setup_intr(dev, sc->intr_res, INTR_TYPE_CLK, rtc_intr, NULL, sc, &sc->intr_handler))) { device_printf(dev, "Can't setup interrupt.\n"); return (0); } else { /* Bind IRQ to BSP to avoid live migration. */ bus_bind_intr(dev, sc->intr_res, 0); } sc->et.et_name = "RTC"; sc->et.et_flags = ET_FLAGS_PERIODIC | ET_FLAGS_POW2DIV; sc->et.et_quality = 0; sc->et.et_frequency = 32768; sc->et.et_min_period = 0x00080000; sc->et.et_max_period = 0x80000000; sc->et.et_start = rtc_start; sc->et.et_stop = rtc_stop; sc->et.et_priv = dev; et_register(&sc->et); } return(0); } static int atrtc_isa_attach(device_t dev) { return (atrtc_attach(dev)); } #ifdef DEV_ACPI static int atrtc_acpi_attach(device_t dev) { int ret; ret = atrtc_attach(dev); if (ret) return (ret); (void)atrtc_reg_acpi_cmos_handler(dev); return (0); } static int atrtc_acpi_detach(device_t dev) { (void)atrtc_unreg_acpi_cmos_handler(dev); return (0); } #endif /* DEV_ACPI */ static int atrtc_resume(device_t dev) { atrtc_restore(); return(0); } static int atrtc_settime(device_t dev __unused, struct timespec *ts) { struct bcd_clocktime bct; clock_ts_to_bcd(ts, &bct, false); clock_dbgprint_bcd(dev, CLOCK_DBG_WRITE, &bct); mtx_lock(&atrtc_time_lock); mtx_lock_spin(&atrtc_lock); /* Disable RTC updates and interrupts. */ rtcout_locked(RTC_STATUSB, RTCSB_HALT | RTCSB_24HR); /* Write all the time registers. */ rtcout_locked(RTC_SEC, bct.sec); rtcout_locked(RTC_MIN, bct.min); rtcout_locked(RTC_HRS, bct.hour); rtcout_locked(RTC_WDAY, bct.dow + 1); rtcout_locked(RTC_DAY, bct.day); rtcout_locked(RTC_MONTH, bct.mon); rtcout_locked(RTC_YEAR, bct.year & 0xff); if (rtc_century) rtcout_locked(rtc_century, bct.year >> 8); /* * Re-enable RTC updates and interrupts. */ rtcout_locked(RTC_STATUSB, rtc_statusb); rtcin_locked(RTC_INTR); mtx_unlock_spin(&atrtc_lock); mtx_unlock(&atrtc_time_lock); return (0); } static int atrtc_gettime(device_t dev, struct timespec *ts) { struct bcd_clocktime bct; /* Look if we have a RTC present and the time is valid */ if (!(rtcin(RTC_STATUSD) & RTCSD_PWR)) { atrtc_power_lost = true; device_printf(dev, "WARNING: Battery failure indication\n"); return (EINVAL); } /* * wait for time update to complete * If RTCSA_TUP is zero, we have at least 244us before next update. * This is fast enough on most hardware, but a refinement would be * to make sure that no more than 240us pass after we start reading, * and try again if so. */ mtx_lock(&atrtc_time_lock); while (rtcin(RTC_STATUSA) & RTCSA_TUP) continue; mtx_lock_spin(&atrtc_lock); bct.sec = rtcin_locked(RTC_SEC); bct.min = rtcin_locked(RTC_MIN); bct.hour = rtcin_locked(RTC_HRS); bct.day = rtcin_locked(RTC_DAY); bct.mon = rtcin_locked(RTC_MONTH); bct.year = rtcin_locked(RTC_YEAR); if (rtc_century) bct.year |= rtcin_locked(rtc_century) << 8; mtx_unlock_spin(&atrtc_lock); mtx_unlock(&atrtc_time_lock); /* dow is unused in timespec conversion and we have no nsec info. */ bct.dow = 0; bct.nsec = 0; clock_dbgprint_bcd(dev, CLOCK_DBG_READ, &bct); return (clock_bcd_to_ts(&bct, ts, false)); } static device_method_t atrtc_isa_methods[] = { /* Device interface */ DEVMETHOD(device_probe, atrtc_probe), DEVMETHOD(device_attach, atrtc_isa_attach), /* XXX stop statclock? */ DEVMETHOD(device_resume, atrtc_resume), /* clock interface */ DEVMETHOD(clock_gettime, atrtc_gettime), DEVMETHOD(clock_settime, atrtc_settime), { 0, 0 } }; static driver_t atrtc_isa_driver = { "atrtc", atrtc_isa_methods, sizeof(struct atrtc_softc), }; #ifdef DEV_ACPI static device_method_t atrtc_acpi_methods[] = { /* Device interface */ DEVMETHOD(device_probe, atrtc_probe), DEVMETHOD(device_attach, atrtc_acpi_attach), DEVMETHOD(device_detach, atrtc_acpi_detach), /* XXX stop statclock? */ DEVMETHOD(device_resume, atrtc_resume), /* clock interface */ DEVMETHOD(clock_gettime, atrtc_gettime), DEVMETHOD(clock_settime, atrtc_settime), { 0, 0 } }; static driver_t atrtc_acpi_driver = { "atrtc", atrtc_acpi_methods, sizeof(struct atrtc_softc), }; #endif /* DEV_ACPI */ static devclass_t atrtc_devclass; DRIVER_MODULE(atrtc, isa, atrtc_isa_driver, atrtc_devclass, 0, 0); #ifdef DEV_ACPI DRIVER_MODULE(atrtc, acpi, atrtc_acpi_driver, atrtc_devclass, 0, 0); #endif ISA_PNP_INFO(atrtc_ids);