// SPDX-License-Identifier: GPL-2.0-only
/*
* Windfarm PowerMac thermal control. SMU based sensors
*
* (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
* <[email protected]>
*/
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/wait.h>
#include <linux/completion.h>
#include <linux/of.h>
#include <asm/machdep.h>
#include <asm/io.h>
#include <asm/sections.h>
#include <asm/smu.h>
#include "windfarm.h"
#define VERSION "0.2"
#undef DEBUG
#ifdef DEBUG
#define DBG(args...) printk(args)
#else
#define DBG(args...) do { } while(0)
#endif
/*
* Various SMU "partitions" calibration objects for which we
* keep pointers here for use by bits & pieces of the driver
*/
static struct smu_sdbp_cpuvcp *cpuvcp;
static int cpuvcp_version;
static struct smu_sdbp_cpudiode *cpudiode;
static struct smu_sdbp_slotspow *slotspow;
static u8 *debugswitches;
/*
* SMU basic sensors objects
*/
static LIST_HEAD(smu_ads);
struct smu_ad_sensor {
struct list_head link;
u32 reg; /* index in SMU */
struct wf_sensor sens;
};
#define to_smu_ads(c) container_of(c, struct smu_ad_sensor, sens)
static void smu_ads_release(struct wf_sensor *sr)
{
struct smu_ad_sensor *ads = to_smu_ads(sr);
kfree(ads);
}
static int smu_read_adc(u8 id, s32 *value)
{
struct smu_simple_cmd cmd;
DECLARE_COMPLETION_ONSTACK(comp);
int rc;
rc = smu_queue_simple(&cmd, SMU_CMD_READ_ADC, 1,
smu_done_complete, &comp, id);
if (rc)
return rc;
wait_for_completion(&comp);
if (cmd.cmd.status != 0)
return cmd.cmd.status;
if (cmd.cmd.reply_len != 2) {
printk(KERN_ERR "winfarm: read ADC 0x%x returned %d bytes !\n",
id, cmd.cmd.reply_len);
return -EIO;
}
*value = *((u16 *)cmd.buffer);
return 0;
}
static int smu_cputemp_get(struct wf_sensor *sr, s32 *value)
{
struct smu_ad_sensor *ads = to_smu_ads(sr);
int rc;
s32 val;
s64 scaled;
rc = smu_read_adc(ads->reg, &val);
if (rc) {
printk(KERN_ERR "windfarm: read CPU temp failed, err %d\n",
rc);
return rc;
}
/* Ok, we have to scale & adjust, taking units into account */
scaled = (s64)(((u64)val) * (u64)cpudiode->m_value);
scaled >>= 3;
scaled += ((s64)cpudiode->b_value) << 9;
*value = (s32)(scaled << 1);
return 0;
}
static int smu_cpuamp_get(struct wf_sensor *sr, s32 *value)
{
struct smu_ad_sensor *ads = to_smu_ads(sr);
s32 val, scaled;
int rc;
rc = smu_read_adc(ads->reg, &val);
if (rc) {
printk(KERN_ERR "windfarm: read CPU current failed, err %d\n",
rc);
return rc;
}
/* Ok, we have to scale & adjust, taking units into account */
scaled = (s32)(val * (u32)cpuvcp->curr_scale);
scaled += (s32)cpuvcp->curr_offset;
*value = scaled << 4;
return 0;
}
static int smu_cpuvolt_get(struct wf_sensor *sr, s32 *value)
{
struct smu_ad_sensor *ads = to_smu_ads(sr);
s32 val, scaled;
int rc;
rc = smu_read_adc(ads->reg, &val);
if (rc) {
printk(KERN_ERR "windfarm: read CPU voltage failed, err %d\n",
rc);
return rc;
}
/* Ok, we have to scale & adjust, taking units into account */
scaled = (s32)(val * (u32)cpuvcp->volt_scale);
scaled += (s32)cpuvcp->volt_offset;
*value = scaled << 4;
return 0;
}
static int smu_slotspow_get(struct wf_sensor *sr, s32 *value)
{
struct smu_ad_sensor *ads = to_smu_ads(sr);
s32 val, scaled;
int rc;
rc = smu_read_adc(ads->reg, &val);
if (rc) {
printk(KERN_ERR "windfarm: read slots power failed, err %d\n",
rc);
return rc;
}
/* Ok, we have to scale & adjust, taking units into account */
scaled = (s32)(val * (u32)slotspow->pow_scale);
scaled += (s32)slotspow->pow_offset;
*value = scaled << 4;
return 0;
}
static const struct wf_sensor_ops smu_cputemp_ops = {
.get_value = smu_cputemp_get,
.release = smu_ads_release,
.owner = THIS_MODULE,
};
static const struct wf_sensor_ops smu_cpuamp_ops = {
.get_value = smu_cpuamp_get,
.release = smu_ads_release,
.owner = THIS_MODULE,
};
static const struct wf_sensor_ops smu_cpuvolt_ops = {
.get_value = smu_cpuvolt_get,
.release = smu_ads_release,
.owner = THIS_MODULE,
};
static const struct wf_sensor_ops smu_slotspow_ops = {
.get_value = smu_slotspow_get,
.release = smu_ads_release,
.owner = THIS_MODULE,
};
static struct smu_ad_sensor *smu_ads_create(struct device_node *node)
{
struct smu_ad_sensor *ads;
const char *l;
const u32 *v;
ads = kmalloc(sizeof(struct smu_ad_sensor), GFP_KERNEL);
if (ads == NULL)
return NULL;
l = of_get_property(node, "location", NULL);
if (l == NULL)
goto fail;
/* We currently pick the sensors based on the OF name and location
* properties, while Darwin uses the sensor-id's.
* The problem with the IDs is that they are model specific while it
* looks like apple has been doing a reasonably good job at keeping
* the names and locations consistents so I'll stick with the names
* and locations for now.
*/
if (of_node_is_type(node, "temp-sensor") &&
!strcmp(l, "CPU T-Diode")) {
ads->sens.ops = &smu_cputemp_ops;
ads->sens.name = "cpu-temp";
if (cpudiode == NULL) {
DBG("wf: cpudiode partition (%02x) not found\n",
SMU_SDB_CPUDIODE_ID);
goto fail;
}
} else if (of_node_is_type(node, "current-sensor") &&
!strcmp(l, "CPU Current")) {
ads->sens.ops = &smu_cpuamp_ops;
ads->sens.name = "cpu-current";
if (cpuvcp == NULL) {
DBG("wf: cpuvcp partition (%02x) not found\n",
SMU_SDB_CPUVCP_ID);
goto fail;
}
} else if (of_node_is_type(node, "voltage-sensor") &&
!strcmp(l, "CPU Voltage")) {
ads->sens.ops = &smu_cpuvolt_ops;
ads->sens.name = "cpu-voltage";
if (cpuvcp == NULL) {
DBG("wf: cpuvcp partition (%02x) not found\n",
SMU_SDB_CPUVCP_ID);
goto fail;
}
} else if (of_node_is_type(node, "power-sensor") &&
!strcmp(l, "Slots Power")) {
ads->sens.ops = &smu_slotspow_ops;
ads->sens.name = "slots-power";
if (slotspow == NULL) {
DBG("wf: slotspow partition (%02x) not found\n",
SMU_SDB_SLOTSPOW_ID);
goto fail;
}
} else
goto fail;
v = of_get_property(node, "reg", NULL);
if (v == NULL)
goto fail;
ads->reg = *v;
if (wf_register_sensor(&ads->sens))
goto fail;
return ads;
fail:
kfree(ads);
return NULL;
}
/*
* SMU Power combo sensor object
*/
struct smu_cpu_power_sensor {
struct list_head link;
struct wf_sensor *volts;
struct wf_sensor *amps;
unsigned int fake_volts : 1;
unsigned int quadratic : 1;
struct wf_sensor sens;
};
#define to_smu_cpu_power(c) container_of(c, struct smu_cpu_power_sensor, sens)
static struct smu_cpu_power_sensor *smu_cpu_power;
static void smu_cpu_power_release(struct wf_sensor *sr)
{
struct smu_cpu_power_sensor *pow = to_smu_cpu_power(sr);
if (pow->volts)
wf_put_sensor(pow->volts);
if (pow->amps)
wf_put_sensor(pow->amps);
kfree(pow);
}
static int smu_cpu_power_get(struct wf_sensor *sr, s32 *value)
{
struct smu_cpu_power_sensor *pow = to_smu_cpu_power(sr);
s32 volts, amps, power;
u64 tmps, tmpa, tmpb;
int rc;
rc = pow->amps->ops->get_value(pow->amps, &s);
if (rc)
return rc;
if (pow->fake_volts) {
*value = amps * 12 - 0x30000;
return 0;
}
rc = pow->volts->ops->get_value(pow->volts, &volts);
if (rc)
return rc;
power = (s32)((((u64)volts) * ((u64)amps)) >> 16);
if (!pow->quadratic) {
*value = power;
return 0;
}
tmps = (((u64)power) * ((u64)power)) >> 16;
tmpa = ((u64)cpuvcp->power_quads[0]) * tmps;
tmpb = ((u64)cpuvcp->power_quads[1]) * ((u64)power);
*value = (tmpa >> 28) + (tmpb >> 28) + (cpuvcp->power_quads[2] >> 12);
return 0;
}
static const struct wf_sensor_ops smu_cpu_power_ops = {
.get_value = smu_cpu_power_get,
.release = smu_cpu_power_release,
.owner = THIS_MODULE,
};
static struct smu_cpu_power_sensor *
smu_cpu_power_create(struct wf_sensor *volts, struct wf_sensor *amps)
{
struct smu_cpu_power_sensor *pow;
pow = kmalloc(sizeof(struct smu_cpu_power_sensor), GFP_KERNEL);
if (pow == NULL)
return NULL;
pow->sens.ops = &smu_cpu_power_ops;
pow->sens.name = "cpu-power";
wf_get_sensor(volts);
pow->volts = volts;
wf_get_sensor(amps);
pow->amps = amps;
/* Some early machines need a faked voltage */
if (debugswitches && ((*debugswitches) & 0x80)) {
printk(KERN_INFO "windfarm: CPU Power sensor using faked"
" voltage !\n");
pow->fake_volts = 1;
} else
pow->fake_volts = 0;
/* Try to use quadratic transforms on PowerMac8,1 and 9,1 for now,
* I yet have to figure out what's up with 8,2 and will have to
* adjust for later, unless we can 100% trust the SDB partition...
*/
if ((of_machine_is_compatible("PowerMac8,1") ||
of_machine_is_compatible("PowerMac8,2") ||
of_machine_is_compatible("PowerMac9,1")) &&
cpuvcp_version >= 2) {
pow->quadratic = 1;
DBG("windfarm: CPU Power using quadratic transform\n");
} else
pow->quadratic = 0;
if (wf_register_sensor(&pow->sens))
goto fail;
return pow;
fail:
kfree(pow);
return NULL;
}
static void smu_fetch_param_partitions(void)
{
const struct smu_sdbp_header *hdr;
/* Get CPU voltage/current/power calibration data */
hdr = smu_get_sdb_partition(SMU_SDB_CPUVCP_ID, NULL);
if (hdr != NULL) {
cpuvcp = (struct smu_sdbp_cpuvcp *)&hdr[1];
/* Keep version around */
cpuvcp_version = hdr->version;
}
/* Get CPU diode calibration data */
hdr = smu_get_sdb_partition(SMU_SDB_CPUDIODE_ID, NULL);
if (hdr != NULL)
cpudiode = (struct smu_sdbp_cpudiode *)&hdr[1];
/* Get slots power calibration data if any */
hdr = smu_get_sdb_partition(SMU_SDB_SLOTSPOW_ID, NULL);
if (hdr != NULL)
slotspow = (struct smu_sdbp_slotspow *)&hdr[1];
/* Get debug switches if any */
hdr = smu_get_sdb_partition(SMU_SDB_DEBUG_SWITCHES_ID, NULL);
if (hdr != NULL)
debugswitches = (u8 *)&hdr[1];
}
static int __init smu_sensors_init(void)
{
struct device_node *smu, *sensors, *s;
struct smu_ad_sensor *volt_sensor = NULL, *curr_sensor = NULL;
if (!smu_present())
return -ENODEV;
/* Get parameters partitions */
smu_fetch_param_partitions();
smu = of_find_node_by_type(NULL, "smu");
if (smu == NULL)
return -ENODEV;
/* Look for sensors subdir */
for_each_child_of_node(smu, sensors)
if (of_node_name_eq(sensors, "sensors"))
break;
of_node_put(smu);
/* Create basic sensors */
for (s = NULL;
sensors && (s = of_get_next_child(sensors, s)) != NULL;) {
struct smu_ad_sensor *ads;
ads = smu_ads_create(s);
if (ads == NULL)
continue;
list_add(&ads->link, &smu_ads);
/* keep track of cpu voltage & current */
if (!strcmp(ads->sens.name, "cpu-voltage"))
volt_sensor = ads;
else if (!strcmp(ads->sens.name, "cpu-current"))
curr_sensor = ads;
}
of_node_put(sensors);
/* Create CPU power sensor if possible */
if (volt_sensor && curr_sensor)
smu_cpu_power = smu_cpu_power_create(&volt_sensor->sens,
&curr_sensor->sens);
return 0;
}
static void __exit smu_sensors_exit(void)
{
struct smu_ad_sensor *ads;
/* dispose of power sensor */
if (smu_cpu_power)
wf_unregister_sensor(&smu_cpu_power->sens);
/* dispose of basic sensors */
while (!list_empty(&smu_ads)) {
ads = list_entry(smu_ads.next, struct smu_ad_sensor, link);
list_del(&ads->link);
wf_unregister_sensor(&ads->sens);
}
}
module_init(smu_sensors_init);
module_exit(smu_sensors_exit);
MODULE_AUTHOR("Benjamin Herrenschmidt <[email protected]>");
MODULE_DESCRIPTION("SMU sensor objects for PowerMacs thermal control");
MODULE_LICENSE("GPL");
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