[PATCH] ppc64: Thermal control for SMU based machines

This adds a new thermal control framework for PowerMac, along with the
implementation for PowerMac8,1, PowerMac8,2 (iMac G5 rev 1 and 2), and
PowerMac9,1 (latest single CPU desktop). In the future, I expect to move
the older G5 thermal control to the new framework as well.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 479 insertions, 0 deletions

diff --git a/drivers/macintosh/windfarm_smu_sensors.c b/drivers/macintosh/windfarm_smu_sensors.c
new file mode 100644
index 00000000000..b558cc209d4
--- /dev/null
+++ b/drivers/macintosh/windfarm_smu_sensors.c
@@ -0,0 +1,479 @@
+/*
+ * Windfarm PowerMac thermal control. SMU based sensors
+ *
+ * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
+ *                    <benh@kernel.crashing.org>
+ *
+ * Released under the term of the GNU GPL v2.
+ */
+
+#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 <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"
+
+#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(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 struct wf_sensor_ops smu_cputemp_ops = {
+        .get_value      = smu_cputemp_get,
+        .release        = smu_ads_release,
+        .owner          = THIS_MODULE,
+};
+static struct wf_sensor_ops smu_cpuamp_ops = {
+        .get_value      = smu_cpuamp_get,
+        .release        = smu_ads_release,
+        .owner          = THIS_MODULE,
+};
+static struct wf_sensor_ops smu_cpuvolt_ops = {
+        .get_value      = smu_cpuvolt_get,
+        .release        = smu_ads_release,
+        .owner          = THIS_MODULE,
+};
+static 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;
+        char *c, *l;
+        u32 *v;
+
+        ads = kmalloc(sizeof(struct smu_ad_sensor), GFP_KERNEL);
+        if (ads == NULL)
+                return NULL;
+        c = (char *)get_property(node, "device_type", NULL);
+        l = (char *)get_property(node, "location", NULL);
+        if (c == NULL || 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 (!strcmp(c, "temp-sensor") &&
+            !strcmp(l, "CPU T-Diode")) {
+                ads->sens.ops = &smu_cputemp_ops;
+                ads->sens.name = "cpu-temp";
+        } else if (!strcmp(c, "current-sensor") &&
+                   !strcmp(l, "CPU Current")) {
+                ads->sens.ops = &smu_cpuamp_ops;
+                ads->sens.name = "cpu-current";
+        } else if (!strcmp(c, "voltage-sensor") &&
+                   !strcmp(l, "CPU Voltage")) {
+                ads->sens.ops = &smu_cpuvolt_ops;
+                ads->sens.name = "cpu-voltage";
+        } else if (!strcmp(c, "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 = (u32 *)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;
+        int                     fake_volts : 1;
+        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, &amps);
+        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 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 ((machine_is_compatible("PowerMac8,1") ||
+             machine_is_compatible("PowerMac8,2") ||
+             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 int smu_fetch_param_partitions(void)
+{
+        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) {
+                DBG("wf: cpuvcp partition (%02x) not found\n",
+                    SMU_SDB_CPUVCP_ID);
+                return -ENODEV;
+        }
+        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) {
+                DBG("wf: cpudiode partition (%02x) not found\n",
+                    SMU_SDB_CPUDIODE_ID);
+                return -ENODEV;
+        }
+        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];
+
+        return 0;
+}
+
+static int __init smu_sensors_init(void)
+{
+        struct device_node *smu, *sensors, *s;
+        struct smu_ad_sensor *volt_sensor = NULL, *curr_sensor = NULL;
+        int rc;
+
+        if (!smu_present())
+                return -ENODEV;
+
+        /* Get parameters partitions */
+        rc = smu_fetch_param_partitions();
+        if (rc)
+                return rc;
+
+        smu = of_find_node_by_type(NULL, "smu");
+        if (smu == NULL)
+                return -ENODEV;
+
+        /* Look for sensors subdir */
+        for (sensors = NULL;
+             (sensors = of_get_next_child(smu, sensors)) != NULL;)
+                if (!strcmp(sensors->name, "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 <benh@kernel.crashing.org>");
+MODULE_DESCRIPTION("SMU sensor objects for PowerMacs thermal control");
+MODULE_LICENSE("GPL");
+