diff options
author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2012-04-18 22:16:55 (GMT) |
---|---|---|
committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2012-04-30 05:37:25 (GMT) |
commit | a78a4a03a75466ff859d989a1a00110ebd0165b0 (patch) | |
tree | af7748ecde199305ab493a32954f7163a4579914 /drivers/macintosh/windfarm_fcu_controls.c | |
parent | d839ba2ab2f3270fe4f067e082a7233ba06bcf9c (diff) | |
download | linux-a78a4a03a75466ff859d989a1a00110ebd0165b0.tar.xz |
powerpc/windfarm: Add Fan Control Unit controls for G5s
The FCU operates the fans on the earlier generation G5 machines,
this module will be used by upcoming windfarm drivers.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'drivers/macintosh/windfarm_fcu_controls.c')
-rw-r--r-- | drivers/macintosh/windfarm_fcu_controls.c | 617 |
1 files changed, 617 insertions, 0 deletions
diff --git a/drivers/macintosh/windfarm_fcu_controls.c b/drivers/macintosh/windfarm_fcu_controls.c new file mode 100644 index 0000000..871f8b4 --- /dev/null +++ b/drivers/macintosh/windfarm_fcu_controls.c @@ -0,0 +1,617 @@ +/* + * Windfarm PowerMac thermal control. FCU fan control + * + * Copyright 2012 Benjamin Herrenschmidt, IBM Corp. + * + * Released under the term of the GNU GPL v2. + */ +#undef DEBUG + +#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/i2c.h> +#include <asm/prom.h> +#include <asm/machdep.h> +#include <asm/io.h> +#include <asm/sections.h> + +#include "windfarm.h" +#include "windfarm_mpu.h" + +#define VERSION "1.0" + +#ifdef DEBUG +#define DBG(args...) printk(args) +#else +#define DBG(args...) do { } while(0) +#endif + +/* + * This option is "weird" :) Basically, if you define this to 1 + * the control loop for the RPMs fans (not PWMs) will apply the + * correction factor obtained from the PID to the actual RPM + * speed read from the FCU. + * + * If you define the below constant to 0, then it will be + * applied to the setpoint RPM speed, that is basically the + * speed we proviously "asked" for. + * + * I'm not sure which of these Apple's algorithm is supposed + * to use + */ +#define RPM_PID_USE_ACTUAL_SPEED 1 + +/* Default min/max for pumps */ +#define CPU_PUMP_OUTPUT_MAX 3200 +#define CPU_PUMP_OUTPUT_MIN 1250 + +#define FCU_FAN_RPM 0 +#define FCU_FAN_PWM 1 + +struct wf_fcu_priv { + struct kref ref; + struct i2c_client *i2c; + struct mutex lock; + struct list_head fan_list; + int rpm_shift; +}; + +struct wf_fcu_fan { + struct list_head link; + int id; + s32 min, max, target; + struct wf_fcu_priv *fcu_priv; + struct wf_control ctrl; +}; + +static void wf_fcu_release(struct kref *ref) +{ + struct wf_fcu_priv *pv = container_of(ref, struct wf_fcu_priv, ref); + + kfree(pv); +} + +static void wf_fcu_fan_release(struct wf_control *ct) +{ + struct wf_fcu_fan *fan = ct->priv; + + kref_put(&fan->fcu_priv->ref, wf_fcu_release); + kfree(fan); +} + +static int wf_fcu_read_reg(struct wf_fcu_priv *pv, int reg, + unsigned char *buf, int nb) +{ + int tries, nr, nw; + + mutex_lock(&pv->lock); + + buf[0] = reg; + tries = 0; + for (;;) { + nw = i2c_master_send(pv->i2c, buf, 1); + if (nw > 0 || (nw < 0 && nw != -EIO) || tries >= 100) + break; + msleep(10); + ++tries; + } + if (nw <= 0) { + pr_err("Failure writing address to FCU: %d", nw); + nr = nw; + goto bail; + } + tries = 0; + for (;;) { + nr = i2c_master_recv(pv->i2c, buf, nb); + if (nr > 0 || (nr < 0 && nr != -ENODEV) || tries >= 100) + break; + msleep(10); + ++tries; + } + if (nr <= 0) + pr_err("wf_fcu: Failure reading data from FCU: %d", nw); + bail: + mutex_unlock(&pv->lock); + return nr; +} + +static int wf_fcu_write_reg(struct wf_fcu_priv *pv, int reg, + const unsigned char *ptr, int nb) +{ + int tries, nw; + unsigned char buf[16]; + + buf[0] = reg; + memcpy(buf+1, ptr, nb); + ++nb; + tries = 0; + for (;;) { + nw = i2c_master_send(pv->i2c, buf, nb); + if (nw > 0 || (nw < 0 && nw != -EIO) || tries >= 100) + break; + msleep(10); + ++tries; + } + if (nw < 0) + pr_err("wf_fcu: Failure writing to FCU: %d", nw); + return nw; +} + +static int wf_fcu_fan_set_rpm(struct wf_control *ct, s32 value) +{ + struct wf_fcu_fan *fan = ct->priv; + struct wf_fcu_priv *pv = fan->fcu_priv; + int rc, shift = pv->rpm_shift; + unsigned char buf[2]; + + if (value < fan->min) + value = fan->min; + if (value > fan->max) + value = fan->max; + + if (fan->target && fan->target == value) + return 0; + fan->target = value; + + buf[0] = value >> (8 - shift); + buf[1] = value << shift; + rc = wf_fcu_write_reg(pv, 0x10 + (fan->id * 2), buf, 2); + if (rc < 0) + return -EIO; + return 0; +} + +static int wf_fcu_fan_get_rpm(struct wf_control *ct, s32 *value) +{ + struct wf_fcu_fan *fan = ct->priv; + struct wf_fcu_priv *pv = fan->fcu_priv; + int rc, reg_base, shift = pv->rpm_shift; + unsigned char failure; + unsigned char active; + unsigned char buf[2]; + + rc = wf_fcu_read_reg(pv, 0xb, &failure, 1); + if (rc != 1) + return -EIO; + if ((failure & (1 << fan->id)) != 0) + return -EFAULT; + rc = wf_fcu_read_reg(pv, 0xd, &active, 1); + if (rc != 1) + return -EIO; + if ((active & (1 << fan->id)) == 0) + return -ENXIO; + + /* Programmed value or real current speed */ +#if RPM_PID_USE_ACTUAL_SPEED + reg_base = 0x11; +#else + reg_base = 0x10; +#endif + rc = wf_fcu_read_reg(pv, reg_base + (fan->id * 2), buf, 2); + if (rc != 2) + return -EIO; + + *value = (buf[0] << (8 - shift)) | buf[1] >> shift; + + return 0; +} + +static int wf_fcu_fan_set_pwm(struct wf_control *ct, s32 value) +{ + struct wf_fcu_fan *fan = ct->priv; + struct wf_fcu_priv *pv = fan->fcu_priv; + unsigned char buf[2]; + int rc; + + if (value < fan->min) + value = fan->min; + if (value > fan->max) + value = fan->max; + + if (fan->target && fan->target == value) + return 0; + fan->target = value; + + value = (value * 2559) / 1000; + buf[0] = value; + rc = wf_fcu_write_reg(pv, 0x30 + (fan->id * 2), buf, 1); + if (rc < 0) + return -EIO; + return 0; +} + +static int wf_fcu_fan_get_pwm(struct wf_control *ct, s32 *value) +{ + struct wf_fcu_fan *fan = ct->priv; + struct wf_fcu_priv *pv = fan->fcu_priv; + unsigned char failure; + unsigned char active; + unsigned char buf[2]; + int rc; + + rc = wf_fcu_read_reg(pv, 0x2b, &failure, 1); + if (rc != 1) + return -EIO; + if ((failure & (1 << fan->id)) != 0) + return -EFAULT; + rc = wf_fcu_read_reg(pv, 0x2d, &active, 1); + if (rc != 1) + return -EIO; + if ((active & (1 << fan->id)) == 0) + return -ENXIO; + + rc = wf_fcu_read_reg(pv, 0x30 + (fan->id * 2), buf, 1); + if (rc != 1) + return -EIO; + + *value = (((s32)buf[0]) * 1000) / 2559; + + return 0; +} + +static s32 wf_fcu_fan_min(struct wf_control *ct) +{ + struct wf_fcu_fan *fan = ct->priv; + + return fan->min; +} + +static s32 wf_fcu_fan_max(struct wf_control *ct) +{ + struct wf_fcu_fan *fan = ct->priv; + + return fan->max; +} + +static const struct wf_control_ops wf_fcu_fan_rpm_ops = { + .set_value = wf_fcu_fan_set_rpm, + .get_value = wf_fcu_fan_get_rpm, + .get_min = wf_fcu_fan_min, + .get_max = wf_fcu_fan_max, + .release = wf_fcu_fan_release, + .owner = THIS_MODULE, +}; + +static const struct wf_control_ops wf_fcu_fan_pwm_ops = { + .set_value = wf_fcu_fan_set_pwm, + .get_value = wf_fcu_fan_get_pwm, + .get_min = wf_fcu_fan_min, + .get_max = wf_fcu_fan_max, + .release = wf_fcu_fan_release, + .owner = THIS_MODULE, +}; + +static void __devinit wf_fcu_get_pump_minmax(struct wf_fcu_fan *fan) +{ + const struct mpu_data *mpu = wf_get_mpu(0); + u16 pump_min = 0, pump_max = 0xffff; + u16 tmp[4]; + + /* Try to fetch pumps min/max infos from eeprom */ + if (mpu) { + memcpy(&tmp, mpu->processor_part_num, 8); + if (tmp[0] != 0xffff && tmp[1] != 0xffff) { + pump_min = max(pump_min, tmp[0]); + pump_max = min(pump_max, tmp[1]); + } + if (tmp[2] != 0xffff && tmp[3] != 0xffff) { + pump_min = max(pump_min, tmp[2]); + pump_max = min(pump_max, tmp[3]); + } + } + + /* Double check the values, this _IS_ needed as the EEPROM on + * some dual 2.5Ghz G5s seem, at least, to have both min & max + * same to the same value ... (grrrr) + */ + if (pump_min == pump_max || pump_min == 0 || pump_max == 0xffff) { + pump_min = CPU_PUMP_OUTPUT_MIN; + pump_max = CPU_PUMP_OUTPUT_MAX; + } + + fan->min = pump_min; + fan->max = pump_max; + + DBG("wf_fcu: pump min/max for %s set to: [%d..%d] RPM\n", + fan->ctrl.name, pump_min, pump_max); +} + +static void __devinit wf_fcu_get_rpmfan_minmax(struct wf_fcu_fan *fan) +{ + struct wf_fcu_priv *pv = fan->fcu_priv; + const struct mpu_data *mpu0 = wf_get_mpu(0); + const struct mpu_data *mpu1 = wf_get_mpu(1); + + /* Default */ + fan->min = 2400 >> pv->rpm_shift; + fan->max = 56000 >> pv->rpm_shift; + + /* CPU fans have min/max in MPU */ + if (mpu0 && !strcmp(fan->ctrl.name, "cpu-front-fan-0")) { + fan->min = max(fan->min, (s32)mpu0->rminn_intake_fan); + fan->max = min(fan->max, (s32)mpu0->rmaxn_intake_fan); + goto bail; + } + if (mpu1 && !strcmp(fan->ctrl.name, "cpu-front-fan-1")) { + fan->min = max(fan->min, (s32)mpu1->rminn_intake_fan); + fan->max = min(fan->max, (s32)mpu1->rmaxn_intake_fan); + goto bail; + } + if (mpu0 && !strcmp(fan->ctrl.name, "cpu-rear-fan-0")) { + fan->min = max(fan->min, (s32)mpu0->rminn_exhaust_fan); + fan->max = min(fan->max, (s32)mpu0->rmaxn_exhaust_fan); + goto bail; + } + if (mpu1 && !strcmp(fan->ctrl.name, "cpu-rear-fan-1")) { + fan->min = max(fan->min, (s32)mpu1->rminn_exhaust_fan); + fan->max = min(fan->max, (s32)mpu1->rmaxn_exhaust_fan); + goto bail; + } + /* Rackmac variants, we just use mpu0 intake */ + if (!strncmp(fan->ctrl.name, "cpu-fan", 7)) { + fan->min = max(fan->min, (s32)mpu0->rminn_intake_fan); + fan->max = min(fan->max, (s32)mpu0->rmaxn_intake_fan); + goto bail; + } + bail: + DBG("wf_fcu: fan min/max for %s set to: [%d..%d] RPM\n", + fan->ctrl.name, fan->min, fan->max); +} + +static void __devinit wf_fcu_add_fan(struct wf_fcu_priv *pv, + const char *name, + int type, int id) +{ + struct wf_fcu_fan *fan; + + fan = kzalloc(sizeof(*fan), GFP_KERNEL); + if (!fan) + return; + fan->fcu_priv = pv; + fan->id = id; + fan->ctrl.name = name; + fan->ctrl.priv = fan; + + /* min/max is oddball but the code comes from + * therm_pm72 which seems to work so ... + */ + if (type == FCU_FAN_RPM) { + if (!strncmp(name, "cpu-pump", strlen("cpu-pump"))) + wf_fcu_get_pump_minmax(fan); + else + wf_fcu_get_rpmfan_minmax(fan); + fan->ctrl.type = WF_CONTROL_RPM_FAN; + fan->ctrl.ops = &wf_fcu_fan_rpm_ops; + } else { + fan->min = 10; + fan->max = 100; + fan->ctrl.type = WF_CONTROL_PWM_FAN; + fan->ctrl.ops = &wf_fcu_fan_pwm_ops; + } + + if (wf_register_control(&fan->ctrl)) { + pr_err("wf_fcu: Failed to register fan %s\n", name); + kfree(fan); + return; + } + list_add(&fan->link, &pv->fan_list); + kref_get(&pv->ref); +} + +static void __devinit wf_fcu_lookup_fans(struct wf_fcu_priv *pv) +{ + /* Translation of device-tree location properties to + * windfarm fan names + */ + static const struct { + const char *dt_name; /* Device-tree name */ + const char *ct_name; /* Control name */ + } loc_trans[] = { + { "BACKSIDE", "backside-fan", }, + { "SYS CTRLR FAN", "backside-fan", }, + { "DRIVE BAY", "drive-bay-fan", }, + { "SLOT", "slots-fan", }, + { "PCI FAN", "slots-fan", }, + { "CPU A INTAKE", "cpu-front-fan-0", }, + { "CPU A EXHAUST", "cpu-rear-fan-0", }, + { "CPU B INTAKE", "cpu-front-fan-1", }, + { "CPU B EXHAUST", "cpu-rear-fan-1", }, + { "CPU A PUMP", "cpu-pump-0", }, + { "CPU B PUMP", "cpu-pump-1", }, + { "CPU A 1", "cpu-fan-a-0", }, + { "CPU A 2", "cpu-fan-b-0", }, + { "CPU A 3", "cpu-fan-c-0", }, + { "CPU B 1", "cpu-fan-a-1", }, + { "CPU B 2", "cpu-fan-b-1", }, + { "CPU B 3", "cpu-fan-c-1", }, + }; + struct device_node *np = NULL, *fcu = pv->i2c->dev.of_node; + int i; + + DBG("Looking up FCU controls in device-tree...\n"); + + while ((np = of_get_next_child(fcu, np)) != NULL) { + int id, type = -1; + const char *loc; + const char *name; + const u32 *reg; + + DBG(" control: %s, type: %s\n", np->name, np->type); + + /* Detect control type */ + if (!strcmp(np->type, "fan-rpm-control") || + !strcmp(np->type, "fan-rpm")) + type = FCU_FAN_RPM; + if (!strcmp(np->type, "fan-pwm-control") || + !strcmp(np->type, "fan-pwm")) + type = FCU_FAN_PWM; + /* Only care about fans for now */ + if (type == -1) + continue; + + /* Lookup for a matching location */ + loc = of_get_property(np, "location", NULL); + reg = of_get_property(np, "reg", NULL); + if (loc == NULL || reg == NULL) + continue; + DBG(" matching location: %s, reg: 0x%08x\n", loc, *reg); + + for (i = 0; i < ARRAY_SIZE(loc_trans); i++) { + if (strncmp(loc, loc_trans[i].dt_name, + strlen(loc_trans[i].dt_name))) + continue; + name = loc_trans[i].ct_name; + + DBG(" location match, name: %s\n", name); + + if (type == FCU_FAN_RPM) + id = ((*reg) - 0x10) / 2; + else + id = ((*reg) - 0x30) / 2; + if (id > 7) { + pr_warning("wf_fcu: Can't parse " + "fan ID in device-tree for %s\n", + np->full_name); + break; + } + wf_fcu_add_fan(pv, name, type, id); + break; + } + } +} + +static void __devinit wf_fcu_default_fans(struct wf_fcu_priv *pv) +{ + /* We only support the default fans for PowerMac7,2 */ + if (!of_machine_is_compatible("PowerMac7,2")) + return; + + wf_fcu_add_fan(pv, "backside-fan", FCU_FAN_PWM, 1); + wf_fcu_add_fan(pv, "drive-bay-fan", FCU_FAN_RPM, 2); + wf_fcu_add_fan(pv, "slots-fan", FCU_FAN_PWM, 2); + wf_fcu_add_fan(pv, "cpu-front-fan-0", FCU_FAN_RPM, 3); + wf_fcu_add_fan(pv, "cpu-rear-fan-0", FCU_FAN_RPM, 4); + wf_fcu_add_fan(pv, "cpu-front-fan-1", FCU_FAN_RPM, 5); + wf_fcu_add_fan(pv, "cpu-rear-fan-1", FCU_FAN_RPM, 6); +} + +static int __devinit wf_fcu_init_chip(struct wf_fcu_priv *pv) +{ + unsigned char buf = 0xff; + int rc; + + rc = wf_fcu_write_reg(pv, 0xe, &buf, 1); + if (rc < 0) + return -EIO; + rc = wf_fcu_write_reg(pv, 0x2e, &buf, 1); + if (rc < 0) + return -EIO; + rc = wf_fcu_read_reg(pv, 0, &buf, 1); + if (rc < 0) + return -EIO; + pv->rpm_shift = (buf == 1) ? 2 : 3; + + pr_debug("wf_fcu: FCU Initialized, RPM fan shift is %d\n", + pv->rpm_shift); + + return 0; +} + +static int __devinit wf_fcu_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct wf_fcu_priv *pv; + + pv = kzalloc(sizeof(*pv), GFP_KERNEL); + if (!pv) + return -ENOMEM; + + kref_init(&pv->ref); + mutex_init(&pv->lock); + INIT_LIST_HEAD(&pv->fan_list); + pv->i2c = client; + + /* + * First we must start the FCU which will query the + * shift value to apply to RPMs + */ + if (wf_fcu_init_chip(pv)) { + pr_err("wf_fcu: Initialization failed !\n"); + kfree(pv); + return -ENXIO; + } + + /* First lookup fans in the device-tree */ + wf_fcu_lookup_fans(pv); + + /* + * Older machines don't have the device-tree entries + * we are looking for, just hard code the list + */ + if (list_empty(&pv->fan_list)) + wf_fcu_default_fans(pv); + + /* Still no fans ? FAIL */ + if (list_empty(&pv->fan_list)) { + pr_err("wf_fcu: Failed to find fans for your machine\n"); + kfree(pv); + return -ENODEV; + } + + dev_set_drvdata(&client->dev, pv); + + return 0; +} + +static int __devexit wf_fcu_remove(struct i2c_client *client) +{ + struct wf_fcu_priv *pv = dev_get_drvdata(&client->dev); + struct wf_fcu_fan *fan; + + while (!list_empty(&pv->fan_list)) { + fan = list_first_entry(&pv->fan_list, struct wf_fcu_fan, link); + list_del(&fan->link); + wf_unregister_control(&fan->ctrl); + } + kref_put(&pv->ref, wf_fcu_release); + return 0; +} + +static const struct i2c_device_id wf_fcu_id[] = { + { "MAC,fcu", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, wf_fcu_id); + +static struct i2c_driver wf_fcu_driver = { + .driver = { + .name = "wf_fcu", + }, + .probe = wf_fcu_probe, + .remove = wf_fcu_remove, + .id_table = wf_fcu_id, +}; + +static int __init wf_fcu_init(void) +{ + return i2c_add_driver(&wf_fcu_driver); +} + +static void __exit wf_fcu_exit(void) +{ + i2c_del_driver(&wf_fcu_driver); +} + + +module_init(wf_fcu_init); +module_exit(wf_fcu_exit); + +MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); +MODULE_DESCRIPTION("FCU control objects for PowerMacs thermal control"); +MODULE_LICENSE("GPL"); + |