[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>
diff --git a/drivers/macintosh/windfarm_pid.h b/drivers/macintosh/windfarm_pid.h
new file mode 100644
index 0000000..a364c2a
--- /dev/null
+++ b/drivers/macintosh/windfarm_pid.h
@@ -0,0 +1,84 @@
+/*
+ * Windfarm PowerMac thermal control. Generic PID helpers
+ *
+ * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
+ * <benh@kernel.crashing.org>
+ *
+ * Released under the term of the GNU GPL v2.
+ *
+ * This is a pair of generic PID helpers that can be used by
+ * control loops. One is the basic PID implementation, the
+ * other one is more specifically tailored to the loops used
+ * for CPU control with 2 input sample types (temp and power)
+ */
+
+/*
+ * *** Simple PID ***
+ */
+
+#define WF_PID_MAX_HISTORY 32
+
+/* This parameter array is passed to the PID algorithm. Currently,
+ * we don't support changing parameters on the fly as it's not needed
+ * but could be implemented (with necessary adjustment of the history
+ * buffer
+ */
+struct wf_pid_param {
+ int interval; /* Interval between samples in seconds */
+ int history_len; /* Size of history buffer */
+ int additive; /* 1: target relative to previous value */
+ s32 gd, gp, gr; /* PID gains */
+ s32 itarget; /* PID input target */
+ s32 min,max; /* min and max target values */
+};
+
+struct wf_pid_state {
+ int first; /* first run of the loop */
+ int index; /* index of current sample */
+ s32 target; /* current target value */
+ s32 samples[WF_PID_MAX_HISTORY]; /* samples history buffer */
+ s32 errors[WF_PID_MAX_HISTORY]; /* error history buffer */
+
+ struct wf_pid_param param;
+};
+
+extern void wf_pid_init(struct wf_pid_state *st, struct wf_pid_param *param);
+extern s32 wf_pid_run(struct wf_pid_state *st, s32 sample);
+
+
+/*
+ * *** CPU PID ***
+ */
+
+#define WF_CPU_PID_MAX_HISTORY 32
+
+/* This parameter array is passed to the CPU PID algorithm. Currently,
+ * we don't support changing parameters on the fly as it's not needed
+ * but could be implemented (with necessary adjustment of the history
+ * buffer
+ */
+struct wf_cpu_pid_param {
+ int interval; /* Interval between samples in seconds */
+ int history_len; /* Size of history buffer */
+ s32 gd, gp, gr; /* PID gains */
+ s32 pmaxadj; /* PID max power adjust */
+ s32 ttarget; /* PID input target */
+ s32 tmax; /* PID input max */
+ s32 min,max; /* min and max target values */
+};
+
+struct wf_cpu_pid_state {
+ int first; /* first run of the loop */
+ int index; /* index of current power */
+ int tindex; /* index of current temp */
+ s32 target; /* current target value */
+ s32 powers[WF_PID_MAX_HISTORY]; /* power history buffer */
+ s32 errors[WF_PID_MAX_HISTORY]; /* error history buffer */
+ s32 temps[2]; /* temp. history buffer */
+
+ struct wf_cpu_pid_param param;
+};
+
+extern void wf_cpu_pid_init(struct wf_cpu_pid_state *st,
+ struct wf_cpu_pid_param *param);
+extern s32 wf_cpu_pid_run(struct wf_cpu_pid_state *st, s32 power, s32 temp);