[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, 282 insertions, 0 deletions

diff --git a/drivers/macintosh/windfarm_smu_controls.c b/drivers/macintosh/windfarm_smu_controls.c
new file mode 100644
index 000000000000..2c3158c81ff2
--- /dev/null
+++ b/drivers/macintosh/windfarm_smu_controls.c
@@ -0,0 +1,282 @@
+/*
+ * Windfarm PowerMac thermal control. SMU based controls
+ *
+ * (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 "0.3"
+
+#undef DEBUG
+
+#ifdef DEBUG
+#define DBG(args...)    printk(args)
+#else
+#define DBG(args...)    do { } while(0)
+#endif
+
+/*
+ * SMU fans control object
+ */
+
+static LIST_HEAD(smu_fans);
+
+struct smu_fan_control {
+        struct list_head        link;
+        int                     fan_type;       /* 0 = rpm, 1 = pwm */
+        u32                     reg;            /* index in SMU */
+        s32                     value;          /* current value */
+        s32                     min, max;       /* min/max values */
+        struct wf_control       ctrl;
+};
+#define to_smu_fan(c) container_of(c, struct smu_fan_control, ctrl)
+
+static int smu_set_fan(int pwm, u8 id, u16 value)
+{
+        struct smu_cmd cmd;
+        u8 buffer[16];
+        DECLARE_COMPLETION(comp);
+        int rc;
+
+        /* Fill SMU command structure */
+        cmd.cmd = SMU_CMD_FAN_COMMAND;
+        cmd.data_len = 14;
+        cmd.reply_len = 16;
+        cmd.data_buf = cmd.reply_buf = buffer;
+        cmd.status = 0;
+        cmd.done = smu_done_complete;
+        cmd.misc = &comp;
+
+        /* Fill argument buffer */
+        memset(buffer, 0, 16);
+        buffer[0] = pwm ? 0x10 : 0x00;
+        buffer[1] = 0x01 << id;
+        *((u16 *)&buffer[2 + id * 2]) = value;
+
+        rc = smu_queue_cmd(&cmd);
+        if (rc)
+                return rc;
+        wait_for_completion(&comp);
+        return cmd.status;
+}
+
+static void smu_fan_release(struct wf_control *ct)
+{
+        struct smu_fan_control *fct = to_smu_fan(ct);
+
+        kfree(fct);
+}
+
+static int smu_fan_set(struct wf_control *ct, s32 value)
+{
+        struct smu_fan_control *fct = to_smu_fan(ct);
+
+        if (value < fct->min)
+                value = fct->min;
+        if (value > fct->max)
+                value = fct->max;
+        fct->value = value;
+
+        return smu_set_fan(fct->fan_type, fct->reg, value);
+}
+
+static int smu_fan_get(struct wf_control *ct, s32 *value)
+{
+        struct smu_fan_control *fct = to_smu_fan(ct);
+        *value = fct->value; /* todo: read from SMU */
+        return 0;
+}
+
+static s32 smu_fan_min(struct wf_control *ct)
+{
+        struct smu_fan_control *fct = to_smu_fan(ct);
+        return fct->min;
+}
+
+static s32 smu_fan_max(struct wf_control *ct)
+{
+        struct smu_fan_control *fct = to_smu_fan(ct);
+        return fct->max;
+}
+
+static struct wf_control_ops smu_fan_ops = {
+        .set_value      = smu_fan_set,
+        .get_value      = smu_fan_get,
+        .get_min        = smu_fan_min,
+        .get_max        = smu_fan_max,
+        .release        = smu_fan_release,
+        .owner          = THIS_MODULE,
+};
+
+static struct smu_fan_control *smu_fan_create(struct device_node *node,
+                                              int pwm_fan)
+{
+        struct smu_fan_control *fct;
+        s32 *v; u32 *reg;
+        char *l;
+
+        fct = kmalloc(sizeof(struct smu_fan_control), GFP_KERNEL);
+        if (fct == NULL)
+                return NULL;
+        fct->ctrl.ops = &smu_fan_ops;
+        l = (char *)get_property(node, "location", NULL);
+        if (l == NULL)
+                goto fail;
+
+        fct->fan_type = pwm_fan;
+        fct->ctrl.type = pwm_fan ? WF_CONTROL_PWM_FAN : WF_CONTROL_RPM_FAN;
+
+        /* We use the name & location here the same way we do for SMU sensors,
+         * see the comment in windfarm_smu_sensors.c. The locations are a bit
+         * less consistent here between the iMac and the desktop models, but
+         * that is good enough for our needs for now at least.
+         *
+         * One problem though is that Apple seem to be inconsistent with case
+         * and the kernel doesn't have strcasecmp =P
+         */
+
+        fct->ctrl.name = NULL;
+
+        /* Names used on desktop models */
+        if (!strcmp(l, "Rear Fan 0") || !strcmp(l, "Rear Fan") ||
+            !strcmp(l, "Rear fan 0") || !strcmp(l, "Rear fan"))
+                fct->ctrl.name = "cpu-rear-fan-0";
+        else if (!strcmp(l, "Rear Fan 1") || !strcmp(l, "Rear fan 1"))
+                fct->ctrl.name = "cpu-rear-fan-1";
+        else if (!strcmp(l, "Front Fan 0") || !strcmp(l, "Front Fan") ||
+                 !strcmp(l, "Front fan 0") || !strcmp(l, "Front fan"))
+                fct->ctrl.name = "cpu-front-fan-0";
+        else if (!strcmp(l, "Front Fan 1") || !strcmp(l, "Front fan 1"))
+                fct->ctrl.name = "cpu-front-fan-1";
+        else if (!strcmp(l, "Slots Fan") || !strcmp(l, "Slots fan"))
+                fct->ctrl.name = "slots-fan";
+        else if (!strcmp(l, "Drive Bay") || !strcmp(l, "Drive bay"))
+                fct->ctrl.name = "drive-bay-fan";
+
+        /* Names used on iMac models */
+        if (!strcmp(l, "System Fan") || !strcmp(l, "System fan"))
+                fct->ctrl.name = "system-fan";
+        else if (!strcmp(l, "CPU Fan") || !strcmp(l, "CPU fan"))
+                fct->ctrl.name = "cpu-fan";
+        else if (!strcmp(l, "Hard Drive") || !strcmp(l, "Hard drive"))
+                fct->ctrl.name = "drive-bay-fan";
+
+        /* Unrecognized fan, bail out */
+        if (fct->ctrl.name == NULL)
+                goto fail;
+
+        /* Get min & max values*/
+        v = (s32 *)get_property(node, "min-value", NULL);
+        if (v == NULL)
+                goto fail;
+        fct->min = *v;
+        v = (s32 *)get_property(node, "max-value", NULL);
+        if (v == NULL)
+                goto fail;
+        fct->max = *v;
+
+        /* Get "reg" value */
+        reg = (u32 *)get_property(node, "reg", NULL);
+        if (reg == NULL)
+                goto fail;
+        fct->reg = *reg;
+
+        if (wf_register_control(&fct->ctrl))
+                goto fail;
+
+        return fct;
+ fail:
+        kfree(fct);
+        return NULL;
+}
+
+
+static int __init smu_controls_init(void)
+{
+        struct device_node *smu, *fans, *fan;
+
+        if (!smu_present())
+                return -ENODEV;
+
+        smu = of_find_node_by_type(NULL, "smu");
+        if (smu == NULL)
+                return -ENODEV;
+
+        /* Look for RPM fans */
+        for (fans = NULL; (fans = of_get_next_child(smu, fans)) != NULL;)
+                if (!strcmp(fans->name, "rpm-fans"))
+                        break;
+        for (fan = NULL;
+             fans && (fan = of_get_next_child(fans, fan)) != NULL;) {
+                struct smu_fan_control *fct;
+
+                fct = smu_fan_create(fan, 0);
+                if (fct == NULL) {
+                        printk(KERN_WARNING "windfarm: Failed to create SMU "
+                               "RPM fan %s\n", fan->name);
+                        continue;
+                }
+                list_add(&fct->link, &smu_fans);
+        }
+        of_node_put(fans);
+
+
+        /* Look for PWM fans */
+        for (fans = NULL; (fans = of_get_next_child(smu, fans)) != NULL;)
+                if (!strcmp(fans->name, "pwm-fans"))
+                        break;
+        for (fan = NULL;
+             fans && (fan = of_get_next_child(fans, fan)) != NULL;) {
+                struct smu_fan_control *fct;
+
+                fct = smu_fan_create(fan, 1);
+                if (fct == NULL) {
+                        printk(KERN_WARNING "windfarm: Failed to create SMU "
+                               "PWM fan %s\n", fan->name);
+                        continue;
+                }
+                list_add(&fct->link, &smu_fans);
+        }
+        of_node_put(fans);
+        of_node_put(smu);
+
+        return 0;
+}
+
+static void __exit smu_controls_exit(void)
+{
+        struct smu_fan_control *fct;
+
+        while (!list_empty(&smu_fans)) {
+                fct = list_entry(smu_fans.next, struct smu_fan_control, link);
+                list_del(&fct->link);
+                wf_unregister_control(&fct->ctrl);
+        }
+}
+
+
+module_init(smu_controls_init);
+module_exit(smu_controls_exit);
+
+MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
+MODULE_DESCRIPTION("SMU control objects for PowerMacs thermal control");
+MODULE_LICENSE("GPL");
+