[POWERPC] cell: use pmi in cpufreq driver
authorChristian Krafft <krafft@de.ibm.com>
Mon, 23 Apr 2007 19:35:42 +0000 (21:35 +0200)
committerArnd Bergmann <arnd@klappe.arndb.de>
Mon, 23 Apr 2007 19:44:39 +0000 (21:44 +0200)
The new PMI driver was added in order to support
cpufreq on blades that require the frequency to
be controlled by the service processor, so use it
on those.

Signed-off-by: Christian Krafft <krafft@de.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
arch/powerpc/platforms/cell/cbe_cpufreq.c

index 9c5d63b7e76c4215bc2735c503d7f30ff21032a7..4495973bff599ebf07009efe3f308b477905b643 100644 (file)
@@ -28,6 +28,8 @@
 #include <asm/processor.h>
 #include <asm/prom.h>
 #include <asm/time.h>
+#include <asm/pmi.h>
+#include <asm/of_platform.h>
 
 #include "cbe_regs.h"
 
@@ -68,6 +70,38 @@ static u64 MIC_Slow_Next_Timer_table[] = {
  * hardware specific functions
  */
 
+static struct of_device *pmi_dev;
+
+static int set_pmode_pmi(int cpu, unsigned int pmode)
+{
+       int ret;
+       pmi_message_t pmi_msg;
+#ifdef DEBUG
+       u64 time;
+#endif
+
+       pmi_msg.type = PMI_TYPE_FREQ_CHANGE;
+       pmi_msg.data1 = cbe_cpu_to_node(cpu);
+       pmi_msg.data2 = pmode;
+
+#ifdef DEBUG
+       time = (u64) get_cycles();
+#endif
+
+       pmi_send_message(pmi_dev, pmi_msg);
+       ret = pmi_msg.data2;
+
+       pr_debug("PMI returned slow mode %d\n", ret);
+
+#ifdef DEBUG
+       time = (u64) get_cycles() - time; /* actual cycles (not cpu cycles!) */
+       time = 1000000000 * time / CLOCK_TICK_RATE; /* time in ns (10^-9) */
+       pr_debug("had to wait %lu ns for a transition\n", time);
+#endif
+       return ret;
+}
+
+
 static int get_pmode(int cpu)
 {
        int ret;
@@ -79,7 +113,7 @@ static int get_pmode(int cpu)
        return ret;
 }
 
-static int set_pmode(int cpu, unsigned int pmode)
+static int set_pmode_reg(int cpu, unsigned int pmode)
 {
        struct cbe_pmd_regs __iomem *pmd_regs;
        struct cbe_mic_tm_regs __iomem *mic_tm_regs;
@@ -120,6 +154,39 @@ static int set_pmode(int cpu, unsigned int pmode)
        return 0;
 }
 
+static int set_pmode(int cpu, unsigned int slow_mode) {
+       if(pmi_dev)
+               return set_pmode_pmi(cpu, slow_mode);
+       else
+               return set_pmode_reg(cpu, slow_mode);
+}
+
+static void cbe_cpufreq_handle_pmi(struct of_device *dev, pmi_message_t pmi_msg)
+{
+       struct cpufreq_policy policy;
+       u8 cpu;
+       u8 cbe_pmode_new;
+
+       BUG_ON (pmi_msg.type != PMI_TYPE_FREQ_CHANGE);
+
+       cpu = cbe_node_to_cpu(pmi_msg.data1);
+       cbe_pmode_new = pmi_msg.data2;
+
+       cpufreq_get_policy(&policy, cpu);
+
+       policy.max = min(policy.max, cbe_freqs[cbe_pmode_new].frequency);
+       policy.min = min(policy.min, policy.max);
+
+       pr_debug("cbe_handle_pmi: new policy.min=%d policy.max=%d\n", policy.min, policy.max);
+       cpufreq_set_policy(&policy);
+}
+
+static struct pmi_handler cbe_pmi_handler = {
+       .type                   = PMI_TYPE_FREQ_CHANGE,
+       .handle_pmi_message     = cbe_cpufreq_handle_pmi,
+};
+
+
 /*
  * cpufreq functions
  */
@@ -234,11 +301,23 @@ static struct cpufreq_driver cbe_cpufreq_driver = {
 
 static int __init cbe_cpufreq_init(void)
 {
+       struct device_node *np;
+
+       np = of_find_node_by_type(NULL, "ibm,pmi");
+
+       pmi_dev = of_find_device_by_node(np);
+
+       if (pmi_dev)
+               pmi_register_handler(pmi_dev, &cbe_pmi_handler);
+
        return cpufreq_register_driver(&cbe_cpufreq_driver);
 }
 
 static void __exit cbe_cpufreq_exit(void)
 {
+       if(pmi_dev)
+               pmi_unregister_handler(pmi_dev, &cbe_pmi_handler);
+
        cpufreq_unregister_driver(&cbe_cpufreq_driver);
 }