diff options
Diffstat (limited to 'sys/powerpc/cpufreq/pmcr.c')
| -rw-r--r-- | sys/powerpc/cpufreq/pmcr.c | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/sys/powerpc/cpufreq/pmcr.c b/sys/powerpc/cpufreq/pmcr.c new file mode 100644 index 000000000000..6ae0777a8ac7 --- /dev/null +++ b/sys/powerpc/cpufreq/pmcr.c @@ -0,0 +1,239 @@ +/*- + * SPDX-License-Identifier: BSD-2-Clause + * + * Copyright (c) 2018 Justin Hibbits + * + * 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 ``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 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 <sys/param.h> +#include <sys/systm.h> +#include <sys/bus.h> +#include <sys/cpu.h> +#include <sys/kernel.h> +#include <sys/module.h> + +#include <dev/ofw/openfirm.h> + +#include "cpufreq_if.h" + +static int pstate_ids[256]; +static int pstate_freqs[256]; +static int npstates; + +static void +parse_pstates(void *dummy __unused) +{ + phandle_t node; + + node = OF_finddevice("/ibm,opal/power-mgt"); + + /* If this fails, npstates will remain 0, and any attachment will bail. */ + if (node == -1) + return; + + npstates = OF_getencprop(node, "ibm,pstate-ids", pstate_ids, + sizeof(pstate_ids)); + if (npstates < 0) { + npstates = 0; + return; + } + + if (OF_getencprop(node, "ibm,pstate-frequencies-mhz", pstate_freqs, + sizeof(pstate_freqs)) != npstates) { + npstates = 0; + return; + } + npstates /= sizeof(cell_t); + +} + +/* Make this a sysinit so it runs before the cpufreq driver attaches. */ +SYSINIT(parse_pstates, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, parse_pstates, NULL); + +#define PMCR_UPPERPS_MASK 0xff00000000000000UL +#define PMCR_UPPERPS_SHIFT 56 +#define PMCR_LOWERPS_MASK 0x00ff000000000000UL +#define PMCR_LOWERPS_SHIFT 48 +#define PMCR_VERSION_MASK 0x0000000f +#define PMCR_VERSION_1 1 + +struct pmcr_softc { + device_t dev; +}; + +static void pmcr_identify(driver_t *driver, device_t parent); +static int pmcr_probe(device_t dev); +static int pmcr_attach(device_t dev); +static int pmcr_settings(device_t dev, struct cf_setting *sets, int *count); +static int pmcr_set(device_t dev, const struct cf_setting *set); +static int pmcr_get(device_t dev, struct cf_setting *set); +static int pmcr_type(device_t dev, int *type); + +static device_method_t pmcr_methods[] = { + /* Device interface */ + DEVMETHOD(device_identify, pmcr_identify), + DEVMETHOD(device_probe, pmcr_probe), + DEVMETHOD(device_attach, pmcr_attach), + + /* cpufreq interface */ + DEVMETHOD(cpufreq_drv_set, pmcr_set), + DEVMETHOD(cpufreq_drv_get, pmcr_get), + DEVMETHOD(cpufreq_drv_type, pmcr_type), + DEVMETHOD(cpufreq_drv_settings, pmcr_settings), + {0, 0} +}; + +static driver_t pmcr_driver = { + "pmcr", + pmcr_methods, + sizeof(struct pmcr_softc) +}; + +DRIVER_MODULE(pmcr, cpu, pmcr_driver, 0, 0); + +static void +pmcr_identify(driver_t *driver, device_t parent) +{ + + /* Make sure we're not being doubly invoked. */ + if (device_find_child(parent, "pmcr", DEVICE_UNIT_ANY) != NULL) + return; + + /* + * We attach a child for every CPU since settings need to + * be performed on every CPU in the SMP case. + */ + if (BUS_ADD_CHILD(parent, 10, "pmcr", DEVICE_UNIT_ANY) == NULL) + device_printf(parent, "add pmcr child failed\n"); +} + +static int +pmcr_probe(device_t dev) +{ + if (resource_disabled("pmcr", 0)) + return (ENXIO); + + if (npstates == 0) + return (ENXIO); + + device_set_desc(dev, "Power Management Control Register"); + return (0); +} + +static int +pmcr_attach(device_t dev) +{ + struct pmcr_softc *sc; + + sc = device_get_softc(dev); + sc->dev = dev; + + cpufreq_register(dev); + return (0); +} + +static int +pmcr_settings(device_t dev, struct cf_setting *sets, int *count) +{ + int i; + + if (sets == NULL || count == NULL) + return (EINVAL); + if (*count < npstates) + return (E2BIG); + + /* Return a list of valid settings for this driver. */ + memset(sets, CPUFREQ_VAL_UNKNOWN, sizeof(*sets) * npstates); + + for (i = 0; i < npstates; i++) { + sets[i].freq = pstate_freqs[i]; + sets[i].spec[0] = pstate_ids[i]; + sets[i].spec[1] = i; + sets[i].dev = dev; + } + *count = npstates; + + return (0); +} + +static int +pmcr_set(device_t dev, const struct cf_setting *set) +{ + register_t pmcr; + + if (set == NULL) + return (EINVAL); + + if (set->spec[1] < 0 || set->spec[1] >= npstates) + return (EINVAL); + + pmcr = ((long)set->spec[0] << PMCR_LOWERPS_SHIFT) & PMCR_LOWERPS_MASK; + pmcr |= ((long)set->spec[0] << PMCR_UPPERPS_SHIFT) & PMCR_UPPERPS_MASK; + pmcr |= PMCR_VERSION_1; + + mtspr(SPR_PMCR, pmcr); + powerpc_sync(); isync(); + + return (0); +} + +static int +pmcr_get(device_t dev, struct cf_setting *set) +{ + register_t pmcr; + int i, pstate; + + if (set == NULL) + return (EINVAL); + + memset(set, CPUFREQ_VAL_UNKNOWN, sizeof(*set)); + + pmcr = mfspr(SPR_PMCR); + + pstate = (pmcr & PMCR_LOWERPS_MASK) >> PMCR_LOWERPS_SHIFT; + + for (i = 0; i < npstates && pstate_ids[i] != pstate; i++) + ; + + if (i == npstates) + return (EINVAL); + + set->spec[0] = pstate; + set->spec[1] = i; + set->freq = pstate_freqs[i]; + + set->dev = dev; + + return (0); +} + +static int +pmcr_type(device_t dev, int *type) +{ + + if (type == NULL) + return (EINVAL); + + *type = CPUFREQ_TYPE_ABSOLUTE; + return (0); +} |