From 09b4d1ee881c8593bfad2a42f838d85070365c3e Mon Sep 17 00:00:00 2001 From: Venkatesh Pallipadi Date: Wed, 14 Dec 2005 15:05:00 -0500 Subject: P-state software coordination for acpi-cpufreq http://bugzilla.kernel.org/show_bug.cgi?id=5737 Signed-off-by: Venkatesh Pallipadi Signed-off-by: Len Brown --- arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c | 285 +++++++++++++++++++--------- 1 file changed, 197 insertions(+), 88 deletions(-) diff --git a/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c index 3852d0a4c1b5..4c7c6e089e87 100644 --- a/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c +++ b/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c @@ -48,12 +48,13 @@ MODULE_LICENSE("GPL"); struct cpufreq_acpi_io { - struct acpi_processor_performance acpi_data; + struct acpi_processor_performance *acpi_data; struct cpufreq_frequency_table *freq_table; unsigned int resume; }; static struct cpufreq_acpi_io *acpi_io_data[NR_CPUS]; +static struct acpi_processor_performance *acpi_perf_data[NR_CPUS]; static struct cpufreq_driver acpi_cpufreq_driver; @@ -104,64 +105,43 @@ acpi_processor_set_performance ( { u16 port = 0; u8 bit_width = 0; + int i = 0; int ret = 0; u32 value = 0; - int i = 0; - struct cpufreq_freqs cpufreq_freqs; - cpumask_t saved_mask; int retval; + struct acpi_processor_performance *perf; dprintk("acpi_processor_set_performance\n"); - /* - * TBD: Use something other than set_cpus_allowed. - * As set_cpus_allowed is a bit racy, - * with any other set_cpus_allowed for this process. - */ - saved_mask = current->cpus_allowed; - set_cpus_allowed(current, cpumask_of_cpu(cpu)); - if (smp_processor_id() != cpu) { - return (-EAGAIN); - } - - if (state == data->acpi_data.state) { + retval = 0; + perf = data->acpi_data; + if (state == perf->state) { if (unlikely(data->resume)) { dprintk("Called after resume, resetting to P%d\n", state); data->resume = 0; } else { dprintk("Already at target state (P%d)\n", state); - retval = 0; - goto migrate_end; + return (retval); } } - dprintk("Transitioning from P%d to P%d\n", - data->acpi_data.state, state); - - /* cpufreq frequency struct */ - cpufreq_freqs.cpu = cpu; - cpufreq_freqs.old = data->freq_table[data->acpi_data.state].frequency; - cpufreq_freqs.new = data->freq_table[state].frequency; - - /* notify cpufreq */ - cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_PRECHANGE); + dprintk("Transitioning from P%d to P%d\n", perf->state, state); /* * First we write the target state's 'control' value to the * control_register. */ - port = data->acpi_data.control_register.address; - bit_width = data->acpi_data.control_register.bit_width; - value = (u32) data->acpi_data.states[state].control; + port = perf->control_register.address; + bit_width = perf->control_register.bit_width; + value = (u32) perf->states[state].control; dprintk("Writing 0x%08x to port 0x%04x\n", value, port); ret = acpi_processor_write_port(port, bit_width, value); if (ret) { dprintk("Invalid port width 0x%04x\n", bit_width); - retval = ret; - goto migrate_end; + return (ret); } /* @@ -177,49 +157,36 @@ acpi_processor_set_performance ( * before giving up. */ - port = data->acpi_data.status_register.address; - bit_width = data->acpi_data.status_register.bit_width; + port = perf->status_register.address; + bit_width = perf->status_register.bit_width; dprintk("Looking for 0x%08x from port 0x%04x\n", - (u32) data->acpi_data.states[state].status, port); + (u32) perf->states[state].status, port); - for (i=0; i<100; i++) { + for (i = 0; i < 100; i++) { ret = acpi_processor_read_port(port, bit_width, &value); if (ret) { dprintk("Invalid port width 0x%04x\n", bit_width); - retval = ret; - goto migrate_end; + return (ret); } - if (value == (u32) data->acpi_data.states[state].status) + if (value == (u32) perf->states[state].status) break; udelay(10); } } else { i = 0; - value = (u32) data->acpi_data.states[state].status; + value = (u32) perf->states[state].status; } - /* notify cpufreq */ - cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_POSTCHANGE); - - if (unlikely(value != (u32) data->acpi_data.states[state].status)) { - unsigned int tmp = cpufreq_freqs.new; - cpufreq_freqs.new = cpufreq_freqs.old; - cpufreq_freqs.old = tmp; - cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_PRECHANGE); - cpufreq_notify_transition(&cpufreq_freqs, CPUFREQ_POSTCHANGE); + if (unlikely(value != (u32) perf->states[state].status)) { printk(KERN_WARNING "acpi-cpufreq: Transition failed\n"); retval = -ENODEV; - goto migrate_end; + return (retval); } dprintk("Transition successful after %d microseconds\n", i * 10); - data->acpi_data.state = state; - - retval = 0; -migrate_end: - set_cpus_allowed(current, saved_mask); + perf->state = state; return (retval); } @@ -231,8 +198,17 @@ acpi_cpufreq_target ( unsigned int relation) { struct cpufreq_acpi_io *data = acpi_io_data[policy->cpu]; + struct acpi_processor_performance *perf; + struct cpufreq_freqs freqs; + cpumask_t online_policy_cpus; + cpumask_t saved_mask; + cpumask_t set_mask; + cpumask_t covered_cpus; + unsigned int cur_state = 0; unsigned int next_state = 0; unsigned int result = 0; + unsigned int j; + unsigned int tmp; dprintk("acpi_cpufreq_setpolicy\n"); @@ -241,11 +217,91 @@ acpi_cpufreq_target ( target_freq, relation, &next_state); - if (result) + if (unlikely(result)) return (result); - result = acpi_processor_set_performance (data, policy->cpu, next_state); + perf = data->acpi_data; + cur_state = perf->state; + freqs.old = data->freq_table[cur_state].frequency; + freqs.new = data->freq_table[next_state].frequency; + + /* cpufreq holds the hotplug lock, so we are safe from here on */ + cpus_and(online_policy_cpus, cpu_online_map, policy->cpus); + for_each_cpu_mask(j, online_policy_cpus) { + freqs.cpu = j; + cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); + } + + /* + * We need to call driver->target() on all or any CPU in + * policy->cpus, depending on policy->shared_type. + */ + saved_mask = current->cpus_allowed; + cpus_clear(covered_cpus); + for_each_cpu_mask(j, online_policy_cpus) { + /* + * Support for SMP systems. + * Make sure we are running on CPU that wants to change freq + */ + cpus_clear(set_mask); + if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) + cpus_or(set_mask, set_mask, online_policy_cpus); + else + cpu_set(j, set_mask); + + set_cpus_allowed(current, set_mask); + if (unlikely(!cpu_isset(smp_processor_id(), set_mask))) { + dprintk("couldn't limit to CPUs in this domain\n"); + result = -EAGAIN; + break; + } + + result = acpi_processor_set_performance (data, j, next_state); + if (result) { + result = -EAGAIN; + break; + } + + if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) + break; + + cpu_set(j, covered_cpus); + } + + for_each_cpu_mask(j, online_policy_cpus) { + freqs.cpu = j; + cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); + } + + if (unlikely(result)) { + /* + * We have failed halfway through the frequency change. + * We have sent callbacks to online_policy_cpus and + * acpi_processor_set_performance() has been called on + * coverd_cpus. Best effort undo.. + */ + + if (!cpus_empty(covered_cpus)) { + for_each_cpu_mask(j, covered_cpus) { + policy->cpu = j; + acpi_processor_set_performance (data, + j, + cur_state); + } + } + + tmp = freqs.new; + freqs.new = freqs.old; + freqs.old = tmp; + for_each_cpu_mask(j, online_policy_cpus) { + freqs.cpu = j; + cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); + cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); + } + } + + set_cpus_allowed(current, saved_mask); return (result); } @@ -271,30 +327,65 @@ acpi_cpufreq_guess_freq ( struct cpufreq_acpi_io *data, unsigned int cpu) { + struct acpi_processor_performance *perf = data->acpi_data; + if (cpu_khz) { /* search the closest match to cpu_khz */ unsigned int i; unsigned long freq; - unsigned long freqn = data->acpi_data.states[0].core_frequency * 1000; + unsigned long freqn = perf->states[0].core_frequency * 1000; - for (i=0; i < (data->acpi_data.state_count - 1); i++) { + for (i = 0; i < (perf->state_count - 1); i++) { freq = freqn; - freqn = data->acpi_data.states[i+1].core_frequency * 1000; + freqn = perf->states[i+1].core_frequency * 1000; if ((2 * cpu_khz) > (freqn + freq)) { - data->acpi_data.state = i; + perf->state = i; return (freq); } } - data->acpi_data.state = data->acpi_data.state_count - 1; + perf->state = perf->state_count - 1; return (freqn); - } else + } else { /* assume CPU is at P0... */ - data->acpi_data.state = 0; - return data->acpi_data.states[0].core_frequency * 1000; - + perf->state = 0; + return perf->states[0].core_frequency * 1000; + } } +/* + * acpi_cpufreq_early_init - initialize ACPI P-States library + * + * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c) + * in order to determine correct frequency and voltage pairings. We can + * do _PDC and _PSD and find out the processor dependency for the + * actual init that will happen later... + */ +static int acpi_cpufreq_early_init_acpi(void) +{ + struct acpi_processor_performance *data; + unsigned int i, j; + + dprintk("acpi_cpufreq_early_init\n"); + + for_each_cpu(i) { + data = kzalloc(sizeof(struct acpi_processor_performance), + GFP_KERNEL); + if (!data) { + for_each_cpu(j) { + kfree(acpi_perf_data[j]); + acpi_perf_data[j] = NULL; + } + return (-ENOMEM); + } + acpi_perf_data[i] = data; + } + + /* Do initialization in ACPI core */ + acpi_processor_preregister_performance(acpi_perf_data); + return 0; +} + static int acpi_cpufreq_cpu_init ( struct cpufreq_policy *policy) @@ -304,41 +395,51 @@ acpi_cpufreq_cpu_init ( struct cpufreq_acpi_io *data; unsigned int result = 0; struct cpuinfo_x86 *c = &cpu_data[policy->cpu]; + struct acpi_processor_performance *perf; dprintk("acpi_cpufreq_cpu_init\n"); + if (!acpi_perf_data[cpu]) + return (-ENODEV); + data = kzalloc(sizeof(struct cpufreq_acpi_io), GFP_KERNEL); if (!data) return (-ENOMEM); + data->acpi_data = acpi_perf_data[cpu]; acpi_io_data[cpu] = data; - result = acpi_processor_register_performance(&data->acpi_data, cpu); + result = acpi_processor_register_performance(data->acpi_data, cpu); if (result) goto err_free; + perf = data->acpi_data; + policy->cpus = perf->shared_cpu_map; + policy->shared_type = perf->shared_type; + if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) { acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS; } /* capability check */ - if (data->acpi_data.state_count <= 1) { + if (perf->state_count <= 1) { dprintk("No P-States\n"); result = -ENODEV; goto err_unreg; } - if ((data->acpi_data.control_register.space_id != ACPI_ADR_SPACE_SYSTEM_IO) || - (data->acpi_data.status_register.space_id != ACPI_ADR_SPACE_SYSTEM_IO)) { + + if ((perf->control_register.space_id != ACPI_ADR_SPACE_SYSTEM_IO) || + (perf->status_register.space_id != ACPI_ADR_SPACE_SYSTEM_IO)) { dprintk("Unsupported address space [%d, %d]\n", - (u32) (data->acpi_data.control_register.space_id), - (u32) (data->acpi_data.status_register.space_id)); + (u32) (perf->control_register.space_id), + (u32) (perf->status_register.space_id)); result = -ENODEV; goto err_unreg; } /* alloc freq_table */ - data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) * (data->acpi_data.state_count + 1), GFP_KERNEL); + data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) * (perf->state_count + 1), GFP_KERNEL); if (!data->freq_table) { result = -ENOMEM; goto err_unreg; @@ -346,9 +447,9 @@ acpi_cpufreq_cpu_init ( /* detect transition latency */ policy->cpuinfo.transition_latency = 0; - for (i=0; iacpi_data.state_count; i++) { - if ((data->acpi_data.states[i].transition_latency * 1000) > policy->cpuinfo.transition_latency) - policy->cpuinfo.transition_latency = data->acpi_data.states[i].transition_latency * 1000; + for (i=0; istate_count; i++) { + if ((perf->states[i].transition_latency * 1000) > policy->cpuinfo.transition_latency) + policy->cpuinfo.transition_latency = perf->states[i].transition_latency * 1000; } policy->governor = CPUFREQ_DEFAULT_GOVERNOR; @@ -356,11 +457,11 @@ acpi_cpufreq_cpu_init ( policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu); /* table init */ - for (i=0; i<=data->acpi_data.state_count; i++) + for (i=0; i<=perf->state_count; i++) { data->freq_table[i].index = i; - if (iacpi_data.state_count) - data->freq_table[i].frequency = data->acpi_data.states[i].core_frequency * 1000; + if (istate_count) + data->freq_table[i].frequency = perf->states[i].core_frequency * 1000; else data->freq_table[i].frequency = CPUFREQ_TABLE_END; } @@ -375,12 +476,12 @@ acpi_cpufreq_cpu_init ( printk(KERN_INFO "acpi-cpufreq: CPU%u - ACPI performance management activated.\n", cpu); - for (i = 0; i < data->acpi_data.state_count; i++) + for (i = 0; i < perf->state_count; i++) dprintk(" %cP%d: %d MHz, %d mW, %d uS\n", - (i == data->acpi_data.state?'*':' '), i, - (u32) data->acpi_data.states[i].core_frequency, - (u32) data->acpi_data.states[i].power, - (u32) data->acpi_data.states[i].transition_latency); + (i == perf->state?'*':' '), i, + (u32) perf->states[i].core_frequency, + (u32) perf->states[i].power, + (u32) perf->states[i].transition_latency); cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu); @@ -395,7 +496,7 @@ acpi_cpufreq_cpu_init ( err_freqfree: kfree(data->freq_table); err_unreg: - acpi_processor_unregister_performance(&data->acpi_data, cpu); + acpi_processor_unregister_performance(perf, cpu); err_free: kfree(data); acpi_io_data[cpu] = NULL; @@ -416,7 +517,7 @@ acpi_cpufreq_cpu_exit ( if (data) { cpufreq_frequency_table_put_attr(policy->cpu); acpi_io_data[policy->cpu] = NULL; - acpi_processor_unregister_performance(&data->acpi_data, policy->cpu); + acpi_processor_unregister_performance(data->acpi_data, policy->cpu); kfree(data); } @@ -462,7 +563,10 @@ acpi_cpufreq_init (void) dprintk("acpi_cpufreq_init\n"); - result = cpufreq_register_driver(&acpi_cpufreq_driver); + result = acpi_cpufreq_early_init_acpi(); + + if (!result) + result = cpufreq_register_driver(&acpi_cpufreq_driver); return (result); } @@ -471,10 +575,15 @@ acpi_cpufreq_init (void) static void __exit acpi_cpufreq_exit (void) { + unsigned int i; dprintk("acpi_cpufreq_exit\n"); cpufreq_unregister_driver(&acpi_cpufreq_driver); + for_each_cpu(i) { + kfree(acpi_perf_data[i]); + acpi_perf_data[i] = NULL; + } return; } -- cgit v1.2.2