[PATCH 04/10] cell: use pmi in cpufreq driver
From: Arnd Bergmann <arnd@arndb.de>
Date: 2007-04-23 19:46:54
From: Christian Krafft <redacted> 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 <redacted> Signed-off-by: Arnd Bergmann <redacted> --- Index: linux-2.6/arch/powerpc/platforms/cell/cbe_cpufreq.c ===================================================================
--- linux-2.6.orig/arch/powerpc/platforms/cell/cbe_cpufreq.c
+++ linux-2.6/arch/powerpc/platforms/cell/cbe_cpufreq.c@@ -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 i 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 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); } --