| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Windfarm PowerMac thermal control. FCU fan control |
| * |
| * Copyright 2012 Benjamin Herrenschmidt, IBM Corp. |
| */ |
| #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/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 using 0 for now which is what therm_pm72 used to do and |
| * what Darwin -apparently- does based on observed behaviour. |
| */ |
| #define RPM_PID_USE_ACTUAL_SPEED 0 |
| |
| /* 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; |
| |
| 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; |
| |
| 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 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 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 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 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, *fcu = pv->i2c->dev.of_node; |
| int i; |
| |
| DBG("Looking up FCU controls in device-tree...\n"); |
| |
| for_each_child_of_node(fcu, np) { |
| int id, type = -1; |
| const char *loc; |
| const char *name; |
| const u32 *reg; |
| |
| DBG(" control: %pOFn, type: %s\n", np, of_node_get_device_type(np)); |
| |
| /* Detect control type */ |
| if (of_node_is_type(np, "fan-rpm-control") || |
| of_node_is_type(np, "fan-rpm")) |
| type = FCU_FAN_RPM; |
| if (of_node_is_type(np, "fan-pwm-control") || |
| of_node_is_type(np, "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_warn("wf_fcu: Can't parse fan ID in device-tree for %pOF\n", np); |
| break; |
| } |
| wf_fcu_add_fan(pv, name, type, id); |
| break; |
| } |
| } |
| } |
| |
| static void 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 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 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 void 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); |
| } |
| |
| static const struct i2c_device_id wf_fcu_id[] = { |
| { "MAC,fcu", 0 }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(i2c, wf_fcu_id); |
| |
| static const struct of_device_id wf_fcu_of_id[] = { |
| { .compatible = "fcu", }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(of, wf_fcu_of_id); |
| |
| static struct i2c_driver wf_fcu_driver = { |
| .driver = { |
| .name = "wf_fcu", |
| .of_match_table = wf_fcu_of_id, |
| }, |
| .probe = wf_fcu_probe, |
| .remove = wf_fcu_remove, |
| .id_table = wf_fcu_id, |
| }; |
| |
| module_i2c_driver(wf_fcu_driver); |
| |
| MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); |
| MODULE_DESCRIPTION("FCU control objects for PowerMacs thermal control"); |
| MODULE_LICENSE("GPL"); |
| |