/* $NetBSD: cpu_speedctl.c,v 1.3 2020/07/06 10:58:06 rin Exp $ */
/*-
* Copyright (c) 2006 Michael Lorenz
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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 <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: cpu_speedctl.c,v 1.3 2020/07/06 10:58:06 rin Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/types.h>
#include <powerpc/psl.h>
#include <powerpc/spr.h>
#include <powerpc/oea/cpufeat.h>
#include <powerpc/oea/spr.h>
#include <sys/sysctl.h>
#include <dev/ofw/openfirm.h>
void init_scom_speedctl(void);
static int scom_speedctl = 0;
static uint32_t scom_speeds[2];
static uint32_t scom_reg[2];
static int sysctl_cpuspeed_temp(SYSCTLFN_ARGS);
static int sysctl_cpuspeed_cur(SYSCTLFN_ARGS);
static int sysctl_cpuspeed_available(SYSCTLFN_ARGS);
void
init_scom_speedctl(void)
{
int node;
const struct sysctlnode *sysctl_node, *me, *freq;
/* do this only once */
if (scom_speedctl != 0) return;
scom_speedctl = 1;
node = OF_finddevice("/cpus/@0");
if (OF_getprop(node, "power-mode-data", scom_reg, 8) != 8)
return;
if (OF_getprop(node, "clock-frequency", scom_speeds, 4) != 4)
return;
scom_speeds[0] = scom_speeds[0] / 1000000; /* Hz -> MHz */
scom_speeds[1] = scom_speeds[0] / 2;
sysctl_node = NULL;
if (sysctl_createv(NULL, 0, NULL,
&me,
CTLFLAG_READWRITE, CTLTYPE_NODE, "cpu", NULL, NULL,
0, NULL, 0, CTL_MACHDEP, CTL_CREATE, CTL_EOL) != 0)
printf("couldn't create 'cpu' node\n");
if (sysctl_createv(NULL, 0, NULL,
&freq,
CTLFLAG_READWRITE, CTLTYPE_NODE, "frequency", NULL, NULL,
0, NULL, 0, CTL_MACHDEP, me->sysctl_num, CTL_CREATE, CTL_EOL) != 0)
printf("couldn't create 'frequency' node\n");
if (sysctl_createv(NULL, 0, NULL,
&sysctl_node,
CTLFLAG_READWRITE | CTLFLAG_OWNDESC,
CTLTYPE_INT, "target", "CPU speed", sysctl_cpuspeed_temp,
0, NULL, 0, CTL_MACHDEP, me->sysctl_num, freq->sysctl_num,
CTL_CREATE, CTL_EOL) == 0) {
} else
printf("couldn't create 'target' node\n");
if (sysctl_createv(NULL, 0, NULL,
&sysctl_node,
CTLFLAG_READWRITE,
CTLTYPE_INT, "current", NULL, sysctl_cpuspeed_cur,
1, NULL, 0, CTL_MACHDEP, me->sysctl_num, freq->sysctl_num,
CTL_CREATE, CTL_EOL) == 0) {
} else
printf("couldn't create 'current' node\n");
if (sysctl_createv(NULL, 0, NULL,
&sysctl_node,
CTLFLAG_READWRITE,
CTLTYPE_STRING, "available", NULL, sysctl_cpuspeed_available,
2, NULL, 0, CTL_MACHDEP, me->sysctl_num, freq->sysctl_num,
CTL_CREATE, CTL_EOL) == 0) {
} else
printf("couldn't create 'available' node\n");
}
static int
sysctl_cpuspeed_temp(SYSCTLFN_ARGS)
{
struct sysctlnode node = *rnode;
int speed, nspeed = -1, mhz;
speed = (scom_read(SCOM_PSR) >> 56) & 3;
if (speed > 1) speed = 1;
mhz = scom_speeds[speed];
node.sysctl_data = &mhz;
if (sysctl_lookup(SYSCTLFN_CALL(&node)) == 0) {
int new_reg;
new_reg = *(int *)node.sysctl_data;
if (new_reg == scom_speeds[0]) {
nspeed = 0;
} else if (new_reg == scom_speeds[1]) {
nspeed = 1;
} else {
printf("%s: new_reg %d\n", __func__, new_reg);
return EINVAL;
}
if (nspeed != speed) {
volatile uint64_t junk;
scom_write(SCOM_PCR, 0x80000000);
scom_write(SCOM_PCR, scom_reg[nspeed]);
junk = scom_read(SCOM_PSR);
__USE(junk);
}
return 0;
}
return EINVAL;
}
static int
sysctl_cpuspeed_cur(SYSCTLFN_ARGS)
{
struct sysctlnode node = *rnode;
uint64_t speed;
int mhz;
speed = (scom_read(SCOM_PSR) >> 56) & 3;
if (speed > 1) speed = 1;
mhz = scom_speeds[speed];
node.sysctl_data = &mhz;
return sysctl_lookup(SYSCTLFN_CALL(&node));
}
static int
sysctl_cpuspeed_available(SYSCTLFN_ARGS)
{
struct sysctlnode node = *rnode;
char buf[128];
snprintf(buf, 128, "%d %d", scom_speeds[0], scom_speeds[1]);
node.sysctl_data = buf;
return(sysctl_lookup(SYSCTLFN_CALL(&node)));
}
SYSCTL_SETUP(sysctl_ams_setup, "sysctl obio subtree setup")
{
sysctl_createv(NULL, 0, NULL, NULL,
CTLFLAG_PERMANENT,
CTLTYPE_NODE, "machdep", NULL,
NULL, 0, NULL, 0,
CTL_MACHDEP, CTL_EOL);
}
