path: root/usr/src/uts/i86pc/io/ppm_plat.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */
/*
 * Copyright (c) 2009, Intel Corporation.
 * All rights reserved.
 */

/*
 * Platform Power Management master pseudo driver platform support.
 */

#include <sys/ddi.h>
#include <sys/sunddi.h>
#include <sys/ppmvar.h>
#include <sys/cpupm.h>

#define	PPM_CPU_PSTATE_DOMAIN_FLG	0x100

/*
 * Used by ppm_redefine_topspeed() to set the highest power level of all CPUs
 * in a domain.
 */
void
ppm_set_topspeed(ppm_dev_t *cpup, int speed)
{
	for (cpup = cpup->domp->devlist; cpup != NULL; cpup = cpup->next)
		(*cpupm_set_topspeed_callb)(cpup->dip, speed);
}

/*
 * Redefine the highest power level for all CPUs in a domain. This
 * functionality is necessary because ACPI uses the _PPC to define
 * a CPU's highest power level *and* allows the _PPC to be redefined
 * dynamically. _PPC changes are communicated through _PPC change
 * notifications caught by the CPU device driver.
 */
void
ppm_redefine_topspeed(void *ctx)
{
	char *str = "ppm_redefine_topspeed";
	ppm_dev_t *cpup;
	ppm_dev_t *ncpup;
	int topspeed;
	int newspeed = -1;

	cpup = PPM_GET_PRIVATE((dev_info_t *)ctx);

	if (cpupm_get_topspeed_callb == NULL ||
	    cpupm_set_topspeed_callb == NULL) {
		cmn_err(CE_WARN, "%s: Cannot process request for instance %d "
		    "since cpupm interfaces are not initialized", str,
		    ddi_get_instance(cpup->dip));
		return;
	}

	if (!(cpup->domp->dflags & PPMD_CPU_READY)) {
		PPMD(D_CPU, ("%s: instance %d received _PPC change "
		    "notification before PPMD_CPU_READY", str,
		    ddi_get_instance(cpup->dip)));
		return;
	}

	/*
	 * Process each CPU in the domain.
	 */
	for (ncpup = cpup->domp->devlist; ncpup != NULL; ncpup = ncpup->next) {
		topspeed = (*cpupm_get_topspeed_callb)(ncpup->dip);
		if (newspeed == -1 || topspeed < newspeed)
			newspeed = topspeed;
	}

	ppm_set_topspeed(cpup, newspeed);
}

/*
 * For x86 platforms CPU domains must be built dynamically at bootime.
 * Until the domains have been built, refuse all power transition
 * requests.
 */
/* ARGSUSED */
boolean_t
ppm_manage_early_cpus(dev_info_t *dip, int new, int *result)
{
	ppm_dev_t *ppmd = PPM_GET_PRIVATE(dip);

	if (!(ppmd->domp->dflags & PPMD_CPU_READY)) {
		PPMD(D_CPU, ("ppm_manage_early_cpus: attempt to manage CPU "
		    "before it was ready dip(0x%p)", (void *)dip));
		return (B_TRUE);
	}
	*result = DDI_FAILURE;
	return (B_FALSE);
}

int
ppm_change_cpu_power(ppm_dev_t *ppmd, int newlevel)
{
#ifdef DEBUG
	char *str = "ppm_change_cpu_power";
#endif
	ppm_unit_t *unitp;
	ppm_domain_t *domp;
	ppm_dev_t *cpup;
	dev_info_t *dip;
	int oldlevel;
	int ret;

	unitp = ddi_get_soft_state(ppm_statep, ppm_inst);
	ASSERT(unitp);
	domp = ppmd->domp;
	cpup = domp->devlist;

	dip = cpup->dip;
	ASSERT(dip);

	oldlevel = cpup->level;

	PPMD(D_CPU, ("%s: old %d, new %d\n", str, oldlevel, newlevel))

	if (newlevel == oldlevel)
		return (DDI_SUCCESS);

	/* bring each cpu to next level */
	for (; cpup; cpup = cpup->next) {
		ret = pm_power(cpup->dip, 0, newlevel);
		PPMD(D_CPU, ("%s: \"%s\", changed to level %d, ret %d\n",
		    str, cpup->path, newlevel, ret))
		if (ret == DDI_SUCCESS) {
			cpup->level = newlevel;
			cpup->rplvl = PM_LEVEL_UNKNOWN;
			continue;
		}

		/*
		 * If the driver was unable to lower cpu speed,
		 * the cpu probably got busy; set the previous
		 * cpus back to the original level
		 */
		if (newlevel < oldlevel)
			ret = ppm_revert_cpu_power(cpup, oldlevel);

		return (ret);
	}

	return (DDI_SUCCESS);
}

/*
 * allocate ppm CPU pstate domain if non-existence,
 * otherwise, add the CPU to the corresponding ppm
 * CPU pstate domain.
 */
void
ppm_alloc_pstate_domains(cpu_t *cp)
{
	cpupm_mach_state_t	*mach_state;
	uint32_t		pm_domain;
	int			sub_domain;
	ppm_domain_t		*domp;
	dev_info_t		*cpu_dip;
	ppm_db_t		*dbp;
	char			path[MAXNAMELEN];

	mach_state = (cpupm_mach_state_t *)(cp->cpu_m.mcpu_pm_mach_state);
	ASSERT(mach_state);
	pm_domain = mach_state->ms_pstate.cma_domain->pm_domain;

	/*
	 * There are two purposes of sub_domain:
	 * 1. skip the orignal ppm CPU domain generated by ppm.conf
	 * 2. A CPU ppm domain could have several pstate domains indeed.
	 */
	sub_domain = pm_domain | PPM_CPU_PSTATE_DOMAIN_FLG;

	/*
	 * Find ppm CPU pstate domain
	 */
	for (domp = ppm_domain_p; domp; domp = domp->next) {
		if ((domp->model == PPMD_CPU) &&
		    (domp->sub_domain == sub_domain)) {
			break;
		}
	}

	/*
	 * Create one ppm CPU pstate domain if no found
	 */
	if (domp == NULL) {
		domp = kmem_zalloc(sizeof (*domp), KM_SLEEP);
		mutex_init(&domp->lock, NULL, MUTEX_DRIVER, NULL);
		mutex_enter(&domp->lock);
		domp->name = kmem_zalloc(MAXNAMELEN, KM_SLEEP);
		(void) snprintf(domp->name, MAXNAMELEN, "cpu_pstate_domain_%d",
		    pm_domain);
		domp->sub_domain = sub_domain;
		domp->dflags = PPMD_LOCK_ALL | PPMD_CPU_READY;
		domp->pwr_cnt = 0;
		domp->pwr_cnt++;
		domp->propname = NULL;
		domp->model = PPMD_CPU;
		domp->status = PPMD_ON;
		cpu_dip = mach_state->ms_dip;
		(void) ddi_pathname(cpu_dip, path);
		dbp = kmem_zalloc(sizeof (struct ppm_db), KM_SLEEP);
		dbp->name = kmem_zalloc((strlen(path) + 1),
		    KM_SLEEP);
		(void) strcpy(dbp->name, path);
		dbp->next = domp->conflist;
		domp->conflist = dbp;
		domp->next = ppm_domain_p;
		ppm_domain_p = domp;
		mutex_exit(&domp->lock);
	}
	/*
	 * We found one matched ppm CPU pstate domain,
	 * add cpu to this domain
	 */
	else {
		mutex_enter(&domp->lock);
		cpu_dip = mach_state->ms_dip;
		(void) ddi_pathname(cpu_dip, path);
		dbp = kmem_zalloc(sizeof (struct ppm_db), KM_SLEEP);
		dbp->name = kmem_zalloc((strlen(path) + 1),
		    KM_SLEEP);
		(void) strcpy(dbp->name, path);
		dbp->next = domp->conflist;
		domp->conflist = dbp;
		domp->pwr_cnt++;
		mutex_exit(&domp->lock);
	}
}

/*
 * remove CPU from the corresponding ppm CPU pstate
 * domain. We only remove CPU from conflist here.
 */
void
ppm_free_pstate_domains(cpu_t *cp)
{
	cpupm_mach_state_t	*mach_state;
	ppm_domain_t		*domp;
	ppm_dev_t		*devp;
	dev_info_t		*cpu_dip;
	ppm_db_t		**dbpp, *pconf;
	char			path[MAXNAMELEN];

	mach_state = (cpupm_mach_state_t *)(cp->cpu_m.mcpu_pm_mach_state);
	ASSERT(mach_state);
	cpu_dip = mach_state->ms_dip;
	(void) ddi_pathname(cpu_dip, path);

	/*
	 * get ppm CPU pstate domain
	 */
	devp = PPM_GET_PRIVATE(cpu_dip);
	ASSERT(devp);
	domp = devp->domp;
	ASSERT(domp);

	/*
	 * remove CPU from conflist
	 */
	mutex_enter(&domp->lock);
	for (dbpp = &domp->conflist; (pconf = *dbpp) != NULL; ) {
		if (strcmp(pconf->name, path) != 0) {
			dbpp = &pconf->next;
			continue;
		}
		*dbpp = pconf->next;
		kmem_free(pconf->name, strlen(pconf->name) + 1);
		kmem_free(pconf, sizeof (*pconf));
	}
	mutex_exit(&domp->lock);
}