/* * arch/ppc/platforms/pmac_cpufreq.c * * Copyright (C) 2002 - 2004 Benjamin Herrenschmidt * Copyright (C) 2004 John Steele Scott * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* WARNING !!! This will cause calibrate_delay() to be called, * but this is an __init function ! So you MUST go edit * init/main.c to make it non-init before enabling DEBUG_FREQ */ #undef DEBUG_FREQ /* * There is a problem with the core cpufreq code on SMP kernels, * it won't recalculate the Bogomips properly */ #ifdef CONFIG_SMP #warning "WARNING, CPUFREQ not recommended on SMP kernels" #endif extern void low_choose_7447a_dfs(int dfs); extern void low_choose_750fx_pll(int pll); extern void low_sleep_handler(void); /* * Currently, PowerMac cpufreq supports only high & low frequencies * that are set by the firmware */ static unsigned int low_freq; static unsigned int hi_freq; static unsigned int cur_freq; /* * Different models uses different mecanisms to switch the frequency */ static int (*set_speed_proc)(int low_speed); /* * Some definitions used by the various speedprocs */ static u32 voltage_gpio; static u32 frequency_gpio; static u32 slew_done_gpio; #define PMAC_CPU_LOW_SPEED 1 #define PMAC_CPU_HIGH_SPEED 0 /* There are only two frequency states for each processor. Values * are in kHz for the time being. */ #define CPUFREQ_HIGH PMAC_CPU_HIGH_SPEED #define CPUFREQ_LOW PMAC_CPU_LOW_SPEED static struct cpufreq_frequency_table pmac_cpu_freqs[] = { {CPUFREQ_HIGH, 0}, {CPUFREQ_LOW, 0}, {0, CPUFREQ_TABLE_END}, }; static inline void wakeup_decrementer(void) { set_dec(tb_ticks_per_jiffy); /* No currently-supported powerbook has a 601, * so use get_tbl, not native */ last_jiffy_stamp(0) = tb_last_stamp = get_tbl(); } #ifdef DEBUG_FREQ static inline void debug_calc_bogomips(void) { /* This will cause a recalc of bogomips and display the * result. We backup/restore the value to avoid affecting the * core cpufreq framework's own calculation. */ extern void calibrate_delay(void); unsigned long save_lpj = loops_per_jiffy; calibrate_delay(); loops_per_jiffy = save_lpj; } #endif /* DEBUG_FREQ */ /* Switch CPU speed under 750FX CPU control */ static int __pmac cpu_750fx_cpu_speed(int low_speed) { #ifdef DEBUG_FREQ printk(KERN_DEBUG "HID1, before: %x\n", mfspr(SPRN_HID1)); #endif #ifdef CONFIG_6xx low_choose_750fx_pll(low_speed); #endif #ifdef DEBUG_FREQ printk(KERN_DEBUG "HID1, after: %x\n", mfspr(SPRN_HID1)); debug_calc_bogomips(); #endif return 0; } /* Switch CPU speed using DFS */ static int __pmac dfs_set_cpu_speed(int low_speed) { if (low_speed == 0) { /* ramping up, set voltage first */ pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, voltage_gpio, 0x05); /* Make sure we sleep for at least 1ms */ msleep(1); } /* set frequency */ low_choose_7447a_dfs(low_speed); if (low_speed == 1) { /* ramping down, set voltage last */ pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, voltage_gpio, 0x04); msleep(1); } return 0; } static unsigned int __pmac dfs_get_cpu_speed(unsigned int cpu) { if (mfspr(SPRN_HID1) & HID1_DFS) return low_freq; else return hi_freq; } /* Switch CPU speed using slewing GPIOs */ static int __pmac gpios_set_cpu_speed(int low_speed) { int gpio; /* If ramping up, set voltage first */ if (low_speed == 0) { pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, voltage_gpio, 0x05); /* Delay is way too big but it's ok, we schedule */ msleep(10); } /* Set frequency */ pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, frequency_gpio, low_speed ? 0x04 : 0x05); udelay(200); do { set_current_state(TASK_UNINTERRUPTIBLE); schedule_timeout(1); gpio = pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, slew_done_gpio, 0); } while((gpio & 0x02) == 0); /* If ramping down, set voltage last */ if (low_speed == 1) { pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, voltage_gpio, 0x04); /* Delay is way too big but it's ok, we schedule */ msleep(10); } #ifdef DEBUG_FREQ debug_calc_bogomips(); #endif return 0; } /* Switch CPU speed under PMU control */ static int __pmac pmu_set_cpu_speed(int low_speed) { struct adb_request req; unsigned long save_l2cr; unsigned long save_l3cr; preempt_disable(); #ifdef DEBUG_FREQ printk(KERN_DEBUG "HID1, before: %x\n", mfspr(SPRN_HID1)); #endif /* Disable all interrupt sources on openpic */ openpic_set_priority(0xf); /* Make sure the decrementer won't interrupt us */ asm volatile("mtdec %0" : : "r" (0x7fffffff)); /* Make sure any pending DEC interrupt occuring while we did * the above didn't re-enable the DEC */ mb(); asm volatile("mtdec %0" : : "r" (0x7fffffff)); /* We can now disable MSR_EE */ local_irq_disable(); /* Giveup the FPU & vec */ enable_kernel_fp(); #ifdef CONFIG_ALTIVEC if (cpu_has_feature(CPU_FTR_ALTIVEC)) enable_kernel_altivec(); #endif /* CONFIG_ALTIVEC */ /* Save & disable L2 and L3 caches */ save_l3cr = _get_L3CR(); /* (returns -1 if not available) */ save_l2cr = _get_L2CR(); /* (returns -1 if not available) */ /* Send the new speed command. My assumption is that this command * will cause PLL_CFG[0..3] to be changed next time CPU goes to sleep */ pmu_request(&req, NULL, 6, PMU_CPU_SPEED, 'W', 'O', 'O', 'F', low_speed); while (!req.complete) pmu_poll(); /* Prepare the northbridge for the speed transition */ pmac_call_feature(PMAC_FTR_SLEEP_STATE,NULL,1,1); /* Call low level code to backup CPU state and recover from * hardware reset */ low_sleep_handler(); /* Restore the northbridge */ pmac_call_feature(PMAC_FTR_SLEEP_STATE,NULL,1,0); /* Restore L2 cache */ if (save_l2cr != 0xffffffff && (save_l2cr & L2CR_L2E) != 0) _set_L2CR(save_l2cr); /* Restore L3 cache */ if (save_l3cr != 0xffffffff && (save_l3cr & L3CR_L3E) != 0) _set_L3CR(save_l3cr); /* Restore userland MMU context */ set_context(current->active_mm->context, current->active_mm->pgd); #ifdef DEBUG_FREQ printk(KERN_DEBUG "HID1, after: %x\n", mfspr(SPRN_HID1)); #endif /* Restore low level PMU operations */ pmu_unlock(); /* Restore decrementer */ wakeup_decrementer(); /* Restore interrupts */ openpic_set_priority(0); /* Let interrupts flow again ... */ local_irq_enable(); #ifdef DEBUG_FREQ debug_calc_bogomips(); #endif preempt_enable(); return 0; } static int __pmac do_set_cpu_speed(int speed_mode) { struct cpufreq_freqs freqs; freqs.old = cur_freq; freqs.new = (speed_mode == PMAC_CPU_HIGH_SPEED) ? hi_freq : low_freq; freqs.cpu = smp_processor_id(); if (freqs.old == freqs.new) return 0; cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); set_speed_proc(speed_mode == PMAC_CPU_LOW_SPEED); cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); cur_freq = (speed_mode == PMAC_CPU_HIGH_SPEED) ? hi_freq : low_freq; return 0; } static int __pmac pmac_cpufreq_verify(struct cpufreq_policy *policy) { return cpufreq_frequency_table_verify(policy, pmac_cpu_freqs); } static int __pmac pmac_cpufreq_target( struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation) { unsigned int newstate = 0; if (cpufreq_frequency_table_target(policy, pmac_cpu_freqs, target_freq, relation, &newstate)) return -EINVAL; return do_set_cpu_speed(newstate); } unsigned int __pmac pmac_get_one_cpufreq(int i) { /* Supports only one CPU for now */ return (i == 0) ? cur_freq : 0; } static int __pmac pmac_cpufreq_cpu_init(struct cpufreq_policy *policy) { if (policy->cpu != 0) return -ENODEV; policy->governor = CPUFREQ_DEFAULT_GOVERNOR; policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL; policy->cur = cur_freq; return cpufreq_frequency_table_cpuinfo(policy, &pmac_cpu_freqs[0]); } static u32 __pmac read_gpio(struct device_node *np) { u32 *reg = (u32 *)get_property(np, "reg", NULL); if (reg == NULL) return 0; /* That works for all keylargos but shall be fixed properly * some day... */ return 0x50 + (*reg); } static struct cpufreq_driver pmac_cpufreq_driver = { .verify = pmac_cpufreq_verify, .target = pmac_cpufreq_target, .init = pmac_cpufreq_cpu_init, .name = "powermac", .owner = THIS_MODULE, }; static int __pmac pmac_cpufreq_init_MacRISC3(struct device_node *cpunode) { struct device_node *volt_gpio_np = of_find_node_by_name(NULL, "voltage-gpio"); struct device_node *freq_gpio_np = of_find_node_by_name(NULL, "frequency-gpio"); struct device_node *slew_done_gpio_np = of_find_node_by_name(NULL, "slewing-done"); u32 *value; /* * Check to see if it's GPIO driven or PMU only * * The way we extract the GPIO address is slightly hackish, but it * works well enough for now. We need to abstract the whole GPIO * stuff sooner or later anyway */ if (volt_gpio_np) voltage_gpio = read_gpio(volt_gpio_np); if (freq_gpio_np) frequency_gpio = read_gpio(freq_gpio_np); if (slew_done_gpio_np) slew_done_gpio = read_gpio(slew_done_gpio_np); /* If we use the frequency GPIOs, calculate the min/max speeds based * on the bus frequencies */ if (frequency_gpio && slew_done_gpio) { int lenp, rc; u32 *freqs, *ratio; freqs = (u32 *)get_property(cpunode, "bus-frequencies", &lenp); lenp /= sizeof(u32); if (freqs == NULL || lenp != 2) { printk(KERN_ERR "cpufreq: bus-frequencies incorrect or missing\n"); return 1; } ratio = (u32 *)get_property(cpunode, "processor-to-bus-ratio*2", NULL); if (ratio == NULL) { printk(KERN_ERR "cpufreq: processor-to-bus-ratio*2 missing\n"); return 1; } /* Get the min/max bus frequencies */ low_freq = min(freqs[0], freqs[1]); hi_freq = max(freqs[0], freqs[1]); /* Grrrr.. It _seems_ that the device-tree is lying on the low bus * frequency, it claims it to be around 84Mhz on some models while * it appears to be approx. 101Mhz on all. Let's hack around here... * fortunately, we don't need to be too precise */ if (low_freq < 98000000) low_freq = 101000000; /* Convert those to CPU core clocks */ low_freq = (low_freq * (*ratio)) / 2000; hi_freq = (hi_freq * (*ratio)) / 2000; /* Now we get the frequencies, we read the GPIO to see what is out current * speed */ rc = pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, frequency_gpio, 0); cur_freq = (rc & 0x01) ? hi_freq : low_freq; set_speed_proc = gpios_set_cpu_speed; return 1; } /* If we use the PMU, look for the min & max frequencies in the * device-tree */ value = (u32 *)get_property(cpunode, "min-clock-frequency", NULL); if (!value) return 1; low_freq = (*value) / 1000; /* The PowerBook G4 12" (PowerBook6,1) has an error in the device-tree * here */ if (low_freq < 100000) low_freq *= 10; value = (u32 *)get_property(cpunode, "max-clock-frequency", NULL); if (!value) return 1; hi_freq = (*value) / 1000; set_speed_proc = pmu_set_cpu_speed; return 0; } static int __pmac pmac_cpufreq_init_7447A(struct device_node *cpunode) { struct device_node *volt_gpio_np; u32 *reg; struct cpufreq_driver *driver = &pmac_cpufreq_driver; /* Look for voltage GPIO */ volt_gpio_np = of_find_node_by_name(NULL, "cpu-vcore-select"); reg = (u32 *)get_property(volt_gpio_np, "reg", NULL); voltage_gpio = *reg; if (!volt_gpio_np){ printk(KERN_ERR "cpufreq: missing cpu-vcore-select gpio\n"); return 1; } /* OF only reports the high frequency */ hi_freq = cur_freq; low_freq = cur_freq/2; /* Read actual frequency from CPU */ driver->get = dfs_get_cpu_speed; cur_freq = driver->get(0); set_speed_proc = dfs_set_cpu_speed; return 0; } /* Currently, we support the following machines: * * - Titanium PowerBook 1Ghz (PMU based, 667Mhz & 1Ghz) * - Titanium PowerBook 800 (PMU based, 667Mhz & 800Mhz) * - Titanium PowerBook 400 (PMU based, 300Mhz & 400Mhz) * - Titanium PowerBook 500 (PMU based, 300Mhz & 500Mhz) * - iBook2 500/600 (PMU based, 400Mhz & 500/600Mhz) * - iBook2 700 (CPU based, 400Mhz & 700Mhz, support low voltage) * - Recent MacRISC3 laptops * - All new machines with 7447A CPUs */ static int __init pmac_cpufreq_setup(void) { struct device_node *cpunode; u32 *value; if (strstr(cmd_line, "nocpufreq")) return 0; /* Assume only one CPU */ cpunode = find_type_devices("cpu"); if (!cpunode) goto out; /* Get current cpu clock freq */ value = (u32 *)get_property(cpunode, "clock-frequency", NULL); if (!value) goto out; cur_freq = (*value) / 1000; /* Check for 7447A based MacRISC3 */ if (machine_is_compatible("MacRISC3") && get_property(cpunode, "dynamic-power-step", NULL) && PVR_VER(mfspr(SPRN_PVR)) == 0x8003) { pmac_cpufreq_init_7447A(cpunode); /* Check for other MacRISC3 machines */ } else if (machine_is_compatible("PowerBook3,4") || machine_is_compatible("PowerBook3,5") || machine_is_compatible("MacRISC3")) { pmac_cpufreq_init_MacRISC3(cpunode); /* Else check for iBook2 500/600 */ } else if (machine_is_compatible("PowerBook4,1")) { hi_freq = cur_freq; low_freq = 400000; set_speed_proc = pmu_set_cpu_speed; } /* Else check for TiPb 400 & 500 */ else if (machine_is_compatible("PowerBook3,2")) { /* We only know about the 400 MHz and the 500Mhz model * they both have 300 MHz as low frequency */ if (cur_freq < 350000 || cur_freq > 550000) goto out; hi_freq = cur_freq; low_freq = 300000; set_speed_proc = pmu_set_cpu_speed; } /* Else check for 750FX */ else if (PVR_VER(mfspr(SPRN_PVR)) == 0x7000) { if (get_property(cpunode, "dynamic-power-step", NULL) == NULL) goto out; hi_freq = cur_freq; value = (u32 *)get_property(cpunode, "reduced-clock-frequency", NULL); if (!value) goto out; low_freq = (*value) / 1000; set_speed_proc = cpu_750fx_cpu_speed; } out: if (set_speed_proc == NULL) return -ENODEV; pmac_cpu_freqs[CPUFREQ_LOW].frequency = low_freq; pmac_cpu_freqs[CPUFREQ_HIGH].frequency = hi_freq; printk(KERN_INFO "Registering PowerMac CPU frequency driver\n"); printk(KERN_INFO "Low: %d Mhz, High: %d Mhz, Boot: %d Mhz\n", low_freq/1000, hi_freq/1000, cur_freq/1000); return cpufreq_register_driver(&pmac_cpufreq_driver); } module_init(pmac_cpufreq_setup);