--- /dev/null
+/*
+ * 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");
+
projects / kernel / kernel-generic.git / commitdiff