[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 00000000000..2c3158c81ff
--- /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");
+