/*
* Windfarm PowerMac thermal control. iMac G5
*
* (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
* <benh@kernel.crashing.org>
*
* Released under the term of the GNU GPL v2.
*
* The algorithm used is the PID control algorithm, used the same
* way the published Darwin code does, using the same values that
* are present in the Darwin 8.2 snapshot property lists (note however
* that none of the code has been re-used, it's a complete re-implementation
*
* The various control loops found in Darwin config file are:
*
* PowerMac8,1 and PowerMac8,2
* ===========================
*
* System Fans control loop. Different based on models. In addition to the
* usual PID algorithm, the control loop gets 2 additional pairs of linear
* scaling factors (scale/offsets) expressed as 4.12 fixed point values
* signed offset, unsigned scale)
*
* The targets are modified such as:
* - the linked control (second control) gets the target value as-is
* (typically the drive fan)
* - the main control (first control) gets the target value scaled with
* the first pair of factors, and is then modified as below
* - the value of the target of the CPU Fan control loop is retrieved,
* scaled with the second pair of factors, and the max of that and
* the scaled target is applied to the main control.
*
* # model_id: 2
* controls : system-fan, drive-bay-fan
* sensors : hd-temp
* PID params : G_d = 0x15400000
* G_p = 0x00200000
* G_r = 0x000002fd
* History = 2 entries
* Input target = 0x3a0000
* Interval = 5s
* linear-factors : offset = 0xff38 scale = 0x0ccd
* offset = 0x0208 scale = 0x07ae
*
* # model_id: 3
* controls : system-fan, drive-bay-fan
* sensors : hd-temp
* PID params : G_d = 0x08e00000
* G_p = 0x00566666
* G_r = 0x0000072b
* History = 2 entries
* Input target = 0x350000
* Interval = 5s
* linear-factors : offset = 0xff38 scale = 0x0ccd
* offset = 0x0000 scale = 0x0000
*
* # model_id: 5
* controls : system-fan
* sensors : hd-temp
* PID params : G_d = 0x15400000
* G_p = 0x00233333
* G_r = 0x000002fd
* History = 2 entries
* Input target = 0x3a0000
* Interval = 5s
* linear-factors : offset = 0x0000 scale = 0x1000
* offset = 0x0091 scale = 0x0bae
*
* CPU Fan control loop. The loop is identical for all models. it
* has an additional pair of scaling factor. This is used to scale the
* systems fan control loop target result (the one before it gets scaled
* by the System Fans control loop itself). Then, the max value of the
* calculated target value and system fan value is sent to the fans
*
* controls : cpu-fan
* sensors : cpu-temp cpu-power
* PID params : From SMU sdb partition
* linear-factors : offset = 0xfb50 scale = 0x1000
*
* CPU Slew control loop. Not implemented. The cpufreq driver in linux is
* completely separate for now, though we could find a way to link it, either
* as a client reacting to overtemp notifications, or directling monitoring
* the CPU temperature
*
* WARNING ! The CPU control loop requires the CPU tmax for the current
* operating point. However, we currently are completely separated from
* the cpufreq driver and thus do not know what the current operating
* point is. Fortunately, we also do not have any hardware supporting anything
* but operating point 0 at the moment, thus we just peek that value directly
* from the SDB partition. If we ever end up with actually slewing the system
* clock and thus changing operating points, we'll have to find a way to
* communicate with the CPU freq driver;
*
*/
#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/spinlock.h>
#include <linux/wait.h>
#include <linux/kmod.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/sections.h>
#include <asm/smu.h>
#include "windfarm.h"
#include "windfarm_pid.h"
#define VERSION "0.4"
#undef DEBUG
#ifdef DEBUG
#define DBG(args...) printk(args)
#else
#define DBG(args...) do { } while(0)
#endif
/* define this to force CPU overtemp to 74 degree, useful for testing
* the overtemp code
*/
#undef HACKED_OVERTEMP
static int wf_smu_mach_model; /* machine model id */
/* Controls & sensors */
static struct wf_sensor *sensor_cpu_power;
static struct wf_sensor *sensor_cpu_temp;
static struct wf_sensor *sensor_hd_temp;
static struct wf_control *fan_cpu_main;
static struct wf_control *fan_hd;
static struct wf_control *fan_system;
static struct wf_control *cpufreq_clamp;
/* Set to kick the control loop into life */
static int wf_smu_all_controls_ok, wf_smu_all_sensors_ok, wf_smu_started;
/* Failure handling.. could be nicer */
#define FAILURE_FAN 0x01
#define FAILURE_SENSOR 0x02
#define FAILURE_OVERTEMP 0x04
static unsigned int wf_smu_failure_state;
static int wf_smu_readjust, wf_smu_skipping;
/*
* ****** System Fans Control Loop ******
*
*/
/* Parameters for the System Fans control loop. Parameters
* not in this table such as interval, history size, ...
* are common to all versions and thus hard coded for now.
*/
struct wf_smu_sys_fans_param {
int model_id;
s32 itarget;
s32 gd, gp, gr;
s16 offset0;
u16 scale0;
s16 offset1;
u16 scale1;
};
#define WF_SMU_SYS_FANS_INTERVAL 5
#define WF_SMU_SYS_FANS_HISTORY_SIZE 2
/* State data used by the system fans control loop
*/
struct wf_smu_sys_fans_state {
int ticks;
s32 sys_setpoint;
s32 hd_setpoint;
s16 offset0;
u16 scale0;
s16 offset1;
u16 scale1;
struct wf_pid_state pid;
};
/*
* Configs for SMU Sytem Fan control loop
*/
static struct wf_smu_sys_fans_param wf_smu_sys_all_params[] = {
/* Model ID 2 */
{
.model_id = 2,
.itarget = 0x3a0000,
.gd = 0x15400000,
.gp = 0x00200000,
.gr = 0x000002fd,
.offset0 = 0xff38,
.scale0 = 0x0ccd,
.offset1 = 0x0208,
.scale1 = 0x07ae,
},
/* Model ID 3 */
{
.model_id = 3,
.itarget = 0x350000,
.gd = 0x08e00000,
.gp = 0x00566666,
.gr = 0x0000072b,
.offset0 = 0xff38,
.scale0 = 0x0ccd,
.offset1 = 0x0000,
.scale1 = 0x0000,
},
/* Model ID 5 */
{
.model_id = 5,
.itarget = 0x3a0000,
.gd = 0x15400000,
.gp = 0x00233333,
.gr = 0x000002fd,
.offset0 = 0x0000,
.scale0 = 0x1000,
.offset1 = 0x0091,
.scale1 = 0x0bae,
},
};
#define WF_SMU_SYS_FANS_NUM_CONFIGS ARRAY_SIZE(wf_smu_sys_all_params)
static struct wf_smu_sys_fans_state *wf_smu_sys_fans;
/*
* ****** CPU Fans Control Loop ******
*
*/
#define WF_SMU_CPU_FANS_INTERVAL 1
#define WF_SMU_CPU_FANS_MAX_HISTORY 16
#define WF_SMU_CPU_FANS_SIBLING_SCALE 0x00001000
#define WF_SMU_CPU_FANS_SIBLING_OFFSET 0xfffffb50
/* State data used by the cpu fans control loop
*/
struct wf_smu_cpu_fans_state {
int ticks;
s32 cpu_setpoint;
s32 scale;
s32 offset;
struct wf_cpu_pid_state pid;
};
static struct wf_smu_cpu_fans_state *wf_smu_cpu_fans;
/*
* ***** Implementation *****
*
*/
static void wf_smu_create_sys_fans(void)
{
struct wf_smu_sys_fans_param *param = NULL;
struct wf_pid_param pid_param;
int i;
/* First, locate the params for this model */
for (i = 0; i < WF_SMU_SYS_FANS_NUM_CONFIGS; i++)
if (wf_smu_sys_all_params[i].model_id == wf_smu_mach_model) {
param = &wf_smu_sys_all_params[i];
break;
}
/* No params found, put fans to max */
if (param == NULL) {
printk(KERN_WARNING "windfarm: System fan config not found "
"for this machine model, max fan speed\n");
goto fail;
}
/* Alloc & initialize state */
wf_smu_sys_fans = kmalloc(sizeof(struct wf_smu_sys_fans_state),
GFP_KERNEL);
if (wf_smu_sys_fans == NULL) {
printk(KERN_WARNING "windfarm: Memory allocation error"
" max fan speed\n");
goto fail;
}
wf_smu_sys_fans->ticks = 1;
wf_smu_sys_fans->scale0 = param->scale0;
wf_smu_sys_fans->offset0 = param->offset0;
wf_smu_sys_fans->scale1 = param->scale1;
wf_smu_sys_fans->offset1 = param->offset1;
/* Fill PID params */
pid_param.gd = param->gd;
pid_param.gp = param->gp;
pid_param.gr = param->gr;
pid_param.interval = WF_SMU_SYS_FANS_INTERVAL;
pid_param.history_len = WF_SMU_SYS_FANS_HISTORY_SIZE;
pid_param.itarget = param->itarget;
pid_param.min = fan_system->ops->get_min(fan_system);
pid_param.max = fan_system->ops->get_max(fan_system);
if (fan_hd) {
pid_param.min =
max(pid_param.min,fan_hd->ops->get_min(fan_hd));
pid_param.max =
min(pid_param.max,fan_hd->ops->get_max(fan_hd));
}
wf_pid_init(&wf_smu_sys_fans->pid, &pid_param);
DBG("wf: System Fan control initialized.\n");
DBG(" itarged=%d.%03d, min=%d RPM, max=%d RPM\n",
FIX32TOPRINT(pid_param.itarget), pid_param.min, pid_param.max);
return;
fail:
if (fan_system)
wf_control_set_max(fan_system);
if (fan_hd)
wf_control_set_max(fan_hd);
}
static void wf_smu_sys_fans_tick(struct wf_smu_sys_fans_state *st)
{
s32 new_setpoint, temp, scaled, cputarget;
int rc;
if (--st->ticks != 0) {
if (wf_smu_readjust)
goto readjust;
return;
}
st->ticks = WF_SMU_SYS_FANS_INTERVAL;
rc = sensor_hd_temp->ops->get_value(sensor_hd_temp, &temp);
if (rc) {
printk(KERN_WARNING "windfarm: HD temp sensor error %d\n",
rc);
wf_smu_failure_state |= FAILURE_SENSOR;
return;
}
DBG("wf_smu: System Fans tick ! HD temp: %d.%03d\n",
FIX32TOPRINT(temp));
if (temp > (st->pid.param.itarget + 0x50000))
wf_smu_failure_state |= FAILURE_OVERTEMP;
new_setpoint = wf_pid_run(&st->pid, temp);
DBG("wf_smu: new_setpoint: %d RPM\n", (int)new_setpoint);
scaled = ((((s64)new_setpoint) * (s64)st->scale0) >> 12) + st->offset0;
DBG("wf_smu: scaled setpoint: %d RPM\n", (int)scaled);
cputarget = wf_smu_cpu_fans ? wf_smu_cpu_fans->pid.target : 0;
cputarget = ((((s64)cputarget) * (s64)st->scale1) >> 12) + st->offset1;
scaled = max(scaled, cputarget);
scaled = max(scaled, st->pid.param.min);
scaled = min(scaled, st->pid.param.max);
DBG("wf_smu: adjusted setpoint: %d RPM\n", (int)scaled);
if (st->sys_setpoint == scaled && new_setpoint == st->hd_setpoint)
return;
st->sys_setpoint = scaled;
st->hd_setpoint = new_setpoint;
readjust:
if (fan_system && wf_smu_failure_state == 0) {
rc = fan_system->ops->set_value(fan_system, st->sys_setpoint);
if (rc) {
printk(KERN_WARNING "windfarm: Sys fan error %d\n",
rc);
wf_smu_failure_state |= FAILURE_FAN;
}
}
if (fan_hd && wf_smu_failure_state == 0) {
rc = fan_hd->ops->set_value(fan_hd, st->hd_setpoint);
if (rc) {
printk(KERN_WARNING "windfarm: HD fan error %d\n",
rc);
wf_smu_failure_state |= FAILURE_FAN;
}
}
}
static void wf_smu_create_cpu_fans(void)
{
struct wf_cpu_pid_param pid_param;
const struct smu_sdbp_header *hdr;
struct smu_sdbp_cpupiddata *piddata;
struct smu_sdbp_fvt *fvt;
s32 tmax, tdelta, maxpow, powadj;
/* First, locate the PID params in SMU SBD */
hdr = smu_get_sdb_partition(SMU_SDB_CPUPIDDATA_ID, NULL);
if (hdr == 0) {
printk(KERN_WARNING "windfarm: CPU PID fan config not found "
"max fan speed\n");
goto fail;
}
piddata = (struct smu_sdbp_cpupiddata *)&hdr[1];
/* Get the FVT params for operating point 0 (the only supported one
* for now) in order to get tmax
*/
hdr = smu_get_sdb_partition(SMU_SDB_FVT_ID, NULL);
if (hdr) {
fvt = (struct smu_sdbp_fvt *)&hdr[1];
tmax = ((s32)fvt->maxtemp) << 16;
} else
tmax = 0x5e0000; /* 94 degree default */
/* Alloc & initialize state */
wf_smu_cpu_fans = kmalloc(sizeof(struct wf_smu_cpu_fans_state),
GFP_KERNEL);
if (wf_smu_cpu_fans == NULL)
goto fail;
wf_smu_cpu_fans->ticks = 1;
wf_smu_cpu_fans->scale = WF_SMU_CPU_FANS_SIBLING_SCALE;
wf_smu_cpu_fans->offset = WF_SMU_CPU_FANS_SIBLING_OFFSET;
/* Fill PID params */
pid_param.interval = WF_SMU_CPU_FANS_INTERVAL;
pid_param.history_len = piddata->history_len;
if (pid_param.history_len > WF_CPU_PID_MAX_HISTORY) {
printk(KERN_WARNING "windfarm: History size overflow on "
"CPU control loop (%d)\n", piddata->history_len);
pid_param.history_len = WF_CPU_PID_MAX_HISTORY;
}
pid_param.gd = piddata->gd;
pid_param.gp = piddata->gp;
pid_param.gr = piddata->gr / pid_param.history_len;
tdelta = ((s32)piddata->target_temp_delta) << 16;
maxpow = ((s32)piddata->max_power) << 16;
powadj = ((s32)piddata->power_adj) << 16;
pid_param.tmax = tmax;
pid_param.ttarget = tmax - tdelta;
pid_param.pmaxadj = maxpow - powadj;
pid_param.min = fan_cpu_main->ops->get_min(fan_cpu_main);
pid_param.max = fan_cpu_main->ops->get_max(fan_cpu_main);
wf_cpu_pid_init(&wf_smu_cpu_fans->pid, &pid_param);
DBG("wf: CPU Fan control initialized.\n");
DBG(" ttarged=%d.%03d, tmax=%d.%03d, min=%d RPM, max=%d RPM\n",
FIX32TOPRINT(pid_param.ttarget), FIX32TOPRINT(pid_param.tmax),
pid_param.min, pid_param.max);
return;
fail:
printk(KERN_WARNING "windfarm: CPU fan config not found\n"
"for this machine model, max fan speed\n");
if (cpufreq_clamp)
wf_control_set_max(cpufreq_clamp);
if (fan_cpu_main)
wf_control_set_max(fan_cpu_main);
}
static void wf_smu_cpu_fans_tick(struct wf_smu_cpu_fans_state *st)
{
s32 new_setpoint, temp, power, systarget;
int rc;
if (--st->ticks != 0) {
if (wf_smu_readjust)
goto readjust;
return;
}
st->ticks = WF_SMU_CPU_FANS_INTERVAL;
rc = sensor_cpu_temp->ops->get_value(sensor_cpu_temp, &temp);
if (rc) {
printk(KERN_WARNING "windfarm: CPU temp sensor error %d\n",
rc);
wf_smu_failure_state |= FAILURE_SENSOR;
return;
}
rc = sensor_cpu_power->ops->get_value(sensor_cpu_power, &power);
if (rc) {
printk(KERN_WARNING "windfarm: CPU power sensor error %d\n",
rc);
wf_smu_failure_state |= FAILURE_SENSOR;
return;
}
DBG("wf_smu: CPU Fans tick ! CPU temp: %d.%03d, power: %d.%03d\n",
FIX32TOPRINT(temp), FIX32TOPRINT(power));
#ifdef HACKED_OVERTEMP
if (temp > 0x4a0000)
wf_smu_failure_state |= FAILURE_OVERTEMP;
#else
if (temp > st->pid.param.tmax)
wf_smu_failure_state |= FAILURE_OVERTEMP;
#endif
new_setpoint = wf_cpu_pid_run(&st->pid, power, temp);
DBG("wf_smu: new_setpoint: %d RPM\n", (int)new_setpoint);
systarget = wf_smu_sys_fans ? wf_smu_sys_fans->pid.target : 0;
systarget = ((((s64)systarget) * (s64)st->scale) >> 12)
+ st->offset;
new_setpoint = max(new_setpoint, systarget);
new_setpoint = max(new_setpoint, st->pid.param.min);
new_setpoint = min(new_setpoint, st->pid.param.max);
DBG("wf_smu: adjusted setpoint: %d RPM\n", (int)new_setpoint);
if (st->cpu_setpoint == new_setpoint)
return;
st->cpu_setpoint = new_setpoint;
readjust:
if (fan_cpu_main && wf_smu_failure_state == 0) {
rc = fan_cpu_main->ops->set_value(fan_cpu_main,
st->cpu_setpoint);
if (rc) {
printk(KERN_WARNING "windfarm: CPU main fan"
