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Diffstat (limited to 'drivers/cpufreq/ppc_cbe_cpufreq_pmi.c')
-rw-r--r--drivers/cpufreq/ppc_cbe_cpufreq_pmi.c156
1 files changed, 156 insertions, 0 deletions
diff --git a/drivers/cpufreq/ppc_cbe_cpufreq_pmi.c b/drivers/cpufreq/ppc_cbe_cpufreq_pmi.c
new file mode 100644
index 000000000000..d29e8da396a0
--- /dev/null
+++ b/drivers/cpufreq/ppc_cbe_cpufreq_pmi.c
@@ -0,0 +1,156 @@
+/*
+ * pmi backend for the cbe_cpufreq driver
+ *
+ * (C) Copyright IBM Deutschland Entwicklung GmbH 2005-2007
+ *
+ * Author: Christian Krafft <krafft@de.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/timer.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+
+#include <asm/processor.h>
+#include <asm/prom.h>
+#include <asm/pmi.h>
+#include <asm/cell-regs.h>
+
+#ifdef DEBUG
+#include <asm/time.h>
+#endif
+
+#include "ppc_cbe_cpufreq.h"
+
+static u8 pmi_slow_mode_limit[MAX_CBE];
+
+bool cbe_cpufreq_has_pmi = false;
+EXPORT_SYMBOL_GPL(cbe_cpufreq_has_pmi);
+
+/*
+ * hardware specific functions
+ */
+
+int cbe_cpufreq_set_pmode_pmi(int cpu, unsigned int pmode)
+{
+ int ret;
+ pmi_message_t pmi_msg;
+#ifdef DEBUG
+ long time;
+#endif
+ pmi_msg.type = PMI_TYPE_FREQ_CHANGE;
+ pmi_msg.data1 = cbe_cpu_to_node(cpu);
+ pmi_msg.data2 = pmode;
+
+#ifdef DEBUG
+ time = jiffies;
+#endif
+ pmi_send_message(pmi_msg);
+
+#ifdef DEBUG
+ time = jiffies - time;
+ time = jiffies_to_msecs(time);
+ pr_debug("had to wait %lu ms for a transition using " \
+ "PMI\n", time);
+#endif
+ ret = pmi_msg.data2;
+ pr_debug("PMI returned slow mode %d\n", ret);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(cbe_cpufreq_set_pmode_pmi);
+
+
+static void cbe_cpufreq_handle_pmi(pmi_message_t pmi_msg)
+{
+ u8 node, slow_mode;
+
+ BUG_ON(pmi_msg.type != PMI_TYPE_FREQ_CHANGE);
+
+ node = pmi_msg.data1;
+ slow_mode = pmi_msg.data2;
+
+ pmi_slow_mode_limit[node] = slow_mode;
+
+ pr_debug("cbe_handle_pmi: node: %d max_freq: %d\n", node, slow_mode);
+}
+
+static int pmi_notifier(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ struct cpufreq_policy *policy = data;
+ struct cpufreq_frequency_table *cbe_freqs;
+ u8 node;
+
+ /* Should this really be called for CPUFREQ_ADJUST, CPUFREQ_INCOMPATIBLE
+ * and CPUFREQ_NOTIFY policy events?)
+ */
+ if (event == CPUFREQ_START)
+ return 0;
+
+ cbe_freqs = cpufreq_frequency_get_table(policy->cpu);
+ node = cbe_cpu_to_node(policy->cpu);
+
+ pr_debug("got notified, event=%lu, node=%u\n", event, node);
+
+ if (pmi_slow_mode_limit[node] != 0) {
+ pr_debug("limiting node %d to slow mode %d\n",
+ node, pmi_slow_mode_limit[node]);
+
+ cpufreq_verify_within_limits(policy, 0,
+
+ cbe_freqs[pmi_slow_mode_limit[node]].frequency);
+ }
+
+ return 0;
+}
+
+static struct notifier_block pmi_notifier_block = {
+ .notifier_call = pmi_notifier,
+};
+
+static struct pmi_handler cbe_pmi_handler = {
+ .type = PMI_TYPE_FREQ_CHANGE,
+ .handle_pmi_message = cbe_cpufreq_handle_pmi,
+};
+
+
+
+static int __init cbe_cpufreq_pmi_init(void)
+{
+ cbe_cpufreq_has_pmi = pmi_register_handler(&cbe_pmi_handler) == 0;
+
+ if (!cbe_cpufreq_has_pmi)
+ return -ENODEV;
+
+ cpufreq_register_notifier(&pmi_notifier_block, CPUFREQ_POLICY_NOTIFIER);
+
+ return 0;
+}
+
+static void __exit cbe_cpufreq_pmi_exit(void)
+{
+ cpufreq_unregister_notifier(&pmi_notifier_block, CPUFREQ_POLICY_NOTIFIER);
+ pmi_unregister_handler(&cbe_pmi_handler);
+}
+
+module_init(cbe_cpufreq_pmi_init);
+module_exit(cbe_cpufreq_pmi_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Christian Krafft <krafft@de.ibm.com>");