/* * Copyright (C) 2002 - 2005 Benjamin Herrenschmidt * and Markus Demleitner * * 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. * * This driver adds basic cpufreq support for SMU & 970FX based G5 Macs, * that is iMac G5 and latest single CPU desktop. */ #undef DEBUG #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define DBG(fmt...) pr_debug(fmt) /* see 970FX user manual */ #define SCOM_PCR 0x0aa001 /* PCR scom addr */ #define PCR_HILO_SELECT 0x80000000U /* 1 = PCR, 0 = PCRH */ #define PCR_SPEED_FULL 0x00000000U /* 1:1 speed value */ #define PCR_SPEED_HALF 0x00020000U /* 1:2 speed value */ #define PCR_SPEED_QUARTER 0x00040000U /* 1:4 speed value */ #define PCR_SPEED_MASK 0x000e0000U /* speed mask */ #define PCR_SPEED_SHIFT 17 #define PCR_FREQ_REQ_VALID 0x00010000U /* freq request valid */ #define PCR_VOLT_REQ_VALID 0x00008000U /* volt request valid */ #define PCR_TARGET_TIME_MASK 0x00006000U /* target time */ #define PCR_STATLAT_MASK 0x00001f00U /* STATLAT value */ #define PCR_SNOOPLAT_MASK 0x000000f0U /* SNOOPLAT value */ #define PCR_SNOOPACC_MASK 0x0000000fU /* SNOOPACC value */ #define SCOM_PSR 0x408001 /* PSR scom addr */ /* warning: PSR is a 64 bits register */ #define PSR_CMD_RECEIVED 0x2000000000000000U /* command received */ #define PSR_CMD_COMPLETED 0x1000000000000000U /* command completed */ #define PSR_CUR_SPEED_MASK 0x0300000000000000U /* current speed */ #define PSR_CUR_SPEED_SHIFT (56) /* * The G5 only supports two frequencies (Quarter speed is not supported) */ #define CPUFREQ_HIGH 0 #define CPUFREQ_LOW 1 static struct cpufreq_frequency_table g5_cpu_freqs[] = { {0, CPUFREQ_HIGH, 0}, {0, CPUFREQ_LOW, 0}, {0, 0, CPUFREQ_TABLE_END}, }; /* Power mode data is an array of the 32 bits PCR values to use for * the various frequencies, retrieved from the device-tree */ static int g5_pmode_cur; static void (*g5_switch_volt)(int speed_mode); static int (*g5_switch_freq)(int speed_mode); static int (*g5_query_freq)(void); static unsigned long transition_latency; #ifdef CONFIG_PMAC_SMU static const u32 *g5_pmode_data; static int g5_pmode_max; static struct smu_sdbp_fvt *g5_fvt_table; /* table of op. points */ static int g5_fvt_count; /* number of op. points */ static int g5_fvt_cur; /* current op. point */ /* * SMU based voltage switching for Neo2 platforms */ static void g5_smu_switch_volt(int speed_mode) { struct smu_simple_cmd cmd; DECLARE_COMPLETION_ONSTACK(comp); smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, smu_done_complete, &comp, 'V', 'S', 'L', 'E', 'W', 0xff, g5_fvt_cur+1, speed_mode); wait_for_completion(&comp); } /* * Platform function based voltage/vdnap switching for Neo2 */ static struct pmf_function *pfunc_set_vdnap0; static struct pmf_function *pfunc_vdnap0_complete; static void g5_vdnap_switch_volt(int speed_mode) { struct pmf_args args; u32 slew, done = 0; unsigned long timeout; slew = (speed_mode == CPUFREQ_LOW) ? 1 : 0; args.count = 1; args.u[0].p = &slew; pmf_call_one(pfunc_set_vdnap0, &args); /* It's an irq GPIO so we should be able to just block here, * I'll do that later after I've properly tested the IRQ code for * platform functions */ timeout = jiffies + HZ/10; while(!time_after(jiffies, timeout)) { args.count = 1; args.u[0].p = &done; pmf_call_one(pfunc_vdnap0_complete, &args); if (done) break; usleep_range(1000, 1000); } if (done == 0) printk(KERN_WARNING "cpufreq: Timeout in clock slewing !\n"); } /* * SCOM based frequency switching for 970FX rev3 */ static int g5_scom_switch_freq(int speed_mode) { unsigned long flags; int to; /* If frequency is going up, first ramp up the voltage */ if (speed_mode < g5_pmode_cur) g5_switch_volt(speed_mode); local_irq_save(flags); /* Clear PCR high */ scom970_write(SCOM_PCR, 0); /* Clear PCR low */ scom970_write(SCOM_PCR, PCR_HILO_SELECT | 0); /* Set PCR low */ scom970_write(SCOM_PCR, PCR_HILO_SELECT | g5_pmode_data[speed_mode]); /* Wait for completion */ for (to = 0; to < 10; to++) { unsigned long psr = scom970_read(SCOM_PSR); if ((psr & PSR_CMD_RECEIVED) == 0 && (((psr >> PSR_CUR_SPEED_SHIFT) ^ (g5_pmode_data[speed_mode] >> PCR_SPEED_SHIFT)) & 0x3) == 0) break; if (psr & PSR_CMD_COMPLETED) break; udelay(100); } local_irq_restore(flags); /* If frequency is going down, last ramp the voltage */ if (speed_mode > g5_pmode_cur) g5_switch_volt(speed_mode); g5_pmode_cur = speed_mode; ppc_proc_freq = g5_cpu_freqs[speed_mode].frequency * 1000ul; return 0; } static int g5_scom_query_freq(void) { unsigned long psr = scom970_read(SCOM_PSR); int i; for (i = 0; i <= g5_pmode_max; i++) if ((((psr >> PSR_CUR_SPEED_SHIFT) ^ (g5_pmode_data[i] >> PCR_SPEED_SHIFT)) & 0x3) == 0) break; return i; } /* * Fake voltage switching for platforms with missing support */ static void g5_dummy_switch_volt(int speed_mode) { } #endif /* CONFIG_PMAC_SMU */ /* * Platform function based voltage switching for PowerMac7,2 & 7,3 */ static struct pmf_function *pfunc_cpu0_volt_high; static struct pmf_function *pfunc_cpu0_volt_low; static struct pmf_function *pfunc_cpu1_volt_high; static struct pmf_function *pfunc_cpu1_volt_low; static void g5_pfunc_switch_volt(int speed_mode) { if (speed_mode == CPUFREQ_HIGH) { if (pfunc_cpu0_volt_high) pmf_call_one(pfunc_cpu0_volt_high, NULL); if (pfunc_cpu1_volt_high) pmf_call_one(pfunc_cpu1_volt_high, NULL); } else { if (pfunc_cpu0_volt_low) pmf_call_one(pfunc_cpu0_volt_low, NULL); if (pfunc_cpu1_volt_low) pmf_call_one(pfunc_cpu1_volt_low, NULL); } usleep_range(10000, 10000); /* should be faster , to fix */ } /* * Platform function based frequency switching for PowerMac7,2 & 7,3 */ static struct pmf_function *pfunc_cpu_setfreq_high; static struct pmf_function *pfunc_cpu_setfreq_low; static struct pmf_function *pfunc_cpu_getfreq; static struct pmf_function *pfunc_slewing_done; static int g5_pfunc_switch_freq(int speed_mode) { struct pmf_args args; u32 done = 0; unsigned long timeout; int rc; DBG("g5_pfunc_switch_freq(%d)\n", speed_mode); /* If frequency is going up, first ramp up the voltage */ if (speed_mode < g5_pmode_cur) g5_switch_volt(speed_mode); /* Do it */ if (speed_mode == CPUFREQ_HIGH) rc = pmf_call_one(pfunc_cpu_setfreq_high, NULL); else rc = pmf_call_one(pfunc_cpu_setfreq_low, NULL); if (rc) printk(KERN_WARNING "cpufreq: pfunc switch error %d\n", rc); /* It's an irq GPIO so we should be able to just block here, * I'll do that later after I've properly tested the IRQ code for * platform functions */ timeout = jiffies + HZ/10; while(!time_after(jiffies, timeout)) { args.count = 1; args.u[0].p = &done; pmf_call_one(pfunc_slewing_done, &args); if (done) break; usleep_range(500, 500); } if (done == 0) printk(KERN_WARNING "cpufreq: Timeout in clock slewing !\n"); /* If frequency is going down, last ramp the voltage */ if (speed_mode > g5_pmode_cur) g5_switch_volt(speed_mode); g5_pmode_cur = speed_mode; ppc_proc_freq = g5_cpu_freqs[speed_mode].frequency * 1000ul; return 0; } static int g5_pfunc_query_freq(void) { struct pmf_args args; u32 val = 0; args.count = 1; args.u[0].p = &val; pmf_call_one(pfunc_cpu_getfreq, &args); return val ? CPUFREQ_HIGH : CPUFREQ_LOW; } /* * Common interface to the cpufreq core */ static int g5_cpufreq_target(struct cpufreq_policy *policy, unsigned int index) { return g5_switch_freq(index); } static unsigned int g5_cpufreq_get_speed(unsigned int cpu) { return g5_cpu_freqs[g5_pmode_cur].frequency; } static int g5_cpufreq_cpu_init(struct cpufreq_policy *policy) { return cpufreq_generic_init(policy, g5_cpu_freqs, transition_latency); } static struct cpufreq_driver g5_cpufreq_driver = { .name = "powermac", .flags = CPUFREQ_CONST_LOOPS, .init = g5_cpufreq_cpu_init, .verify = cpufreq_generic_frequency_table_verify, .target_index = g5_cpufreq_target, .get = g5_cpufreq_get_speed, .attr = cpufreq_generic_attr, }; #ifdef CONFIG_PMAC_SMU static int __init g5_neo2_cpufreq_init(struct device_node *cpunode) { unsigned int psize, ssize; unsigned long max_freq; char *freq_method, *volt_method; const u32 *valp; u32 pvr_hi; int use_volts_vdnap = 0; int use_volts_smu = 0; int rc = -ENODEV; /* Check supported platforms */ if (of_machine_is_compatible("PowerMac8,1") || of_machine_is_compatible("PowerMac8,2") || of_machine_is_compatible("PowerMac9,1") || of_machine_is_compatible("PowerMac12,1")) use_volts_smu = 1; else if (of_machine_is_compatible("PowerMac11,2")) use_volts_vdnap = 1; else return -ENODEV; /* Check 970FX for now */ valp = of_get_property(cpunode, "cpu-version", NULL); if (!valp) { DBG("No cpu-version property !\n"); goto bail_noprops; } pvr_hi = (*valp) >> 16; if (pvr_hi != 0x3c && pvr_hi != 0x44) { printk(KERN_ERR "cpufreq: Unsupported CPU version\n"); goto bail_noprops; } /* Look for the powertune data in the device-tree */ g5_pmode_data = of_get_property(cpunode, "power-mode-data",&psize); if (!g5_pmode_data) { DBG("No power-mode-data !\n"); goto bail_noprops; } g5_pmode_max = psize / sizeof(u32) - 1; if (use_volts_smu) { const struct smu_sdbp_header *shdr; /* Look for the FVT table */ shdr = smu_get_sdb_partition(SMU_SDB_FVT_ID, NULL); if (!shdr) goto bail_noprops; g5_fvt_table = (struct smu_sdbp_fvt *)&shdr[1]; ssize = (shdr->len * sizeof(u32)) - sizeof(*shdr); g5_fvt_count = ssize / sizeof(*g5_fvt_table); g5_fvt_cur = 0; /* Sanity checking */ if (g5_fvt_count < 1 || g5_pmode_max < 1) goto bail_noprops; g5_switch_volt = g5_smu_switch_volt; volt_method = "SMU"; } else if (use_volts_vdnap) { struct device_node *root; root = of_find_node_by_path("/"); if (root == NULL) { printk(KERN_ERR "cpufreq: Can't find root of " "device tree\n"); goto bail_noprops; } pfunc_set_vdnap0 = pmf_find_function(root, "set-vdnap0"); pfunc_vdnap0_complete = pmf_find_function(root, "slewing-done"); if (pfunc_set_vdnap0 == NULL || pfunc_vdnap0_complete == NULL) { printk(KERN_ERR "cpufreq: Can't find required " "platform function\n"); goto bail_noprops; } g5_switch_volt = g5_vdnap_switch_volt; volt_method = "GPIO"; } else { g5_switch_volt = g5_dummy_switch_volt; volt_method = "none"; } /* * From what I see, clock-frequency is always the maximal frequency. * The current driver can not slew sysclk yet, so we really only deal * with powertune steps for now. We also only implement full freq and * half freq in this version. So far, I haven't yet seen a machine * supporting anything else. */ valp = of_get_property(cpunode, "clock-frequency", NULL); if (!valp) return -ENODEV; max_freq = (*valp)/1000; g5_cpu_freqs[0].frequency = max_freq; g5_cpu_freqs[1].frequency = max_freq/2; /* Set callbacks */ transition_latency = 12000; g5_switch_freq = g5_scom_switch_freq; g5_query_freq = g5_scom_query_freq; freq_method = "SCOM"; /* Force apply current frequency to make sure everything is in * sync (voltage is right for example). Firmware may leave us with * a strange setting ... */ g5_switch_volt(CPUFREQ_HIGH); msleep(10); g5_pmode_cur = -1; g5_switch_freq(g5_query_freq()); printk(KERN_INFO "Registering G5 CPU frequency driver\n"); printk(KERN_INFO "Frequency method: %s, Voltage method: %s\n", freq_method, volt_method); printk(KERN_INFO "Low: %d Mhz, High: %d Mhz, Cur: %d MHz\n", g5_cpu_freqs[1].frequency/1000, g5_cpu_freqs[0].frequency/1000, g5_cpu_freqs[g5_pmode_cur].frequency/1000); rc = cpufreq_register_driver(&g5_cpufreq_driver); /* We keep the CPU node on hold... hopefully, Apple G5 don't have * hotplug CPU with a dynamic device-tree ... */ return rc; bail_noprops: of_node_put(cpunode); return rc; } #endif /* CONFIG_PMAC_SMU */ static int __init g5_pm72_cpufreq_init(struct device_node *cpunode) { struct device_node *cpuid = NULL, *hwclock = NULL; const u8 *eeprom = NULL; const u32 *valp; u64 max_freq, min_freq, ih, il; int has_volt = 1, rc = 0; DBG("cpufreq: Initializing for PowerMac7,2, PowerMac7,3 and" " RackMac3,1...\n"); /* Lookup the cpuid eeprom node */ cpuid = of_find_node_by_path("/u3@0,f8000000/i2c@f8001000/cpuid@a0"); if (cpuid != NULL) eeprom = of_get_property(cpuid, "cpuid", NULL); if (eeprom == NULL) { printk(KERN_ERR "cpufreq: Can't find cpuid EEPROM !\n"); rc = -ENODEV; goto bail; } /* Lookup the i2c hwclock */ for_each_node_by_name(hwclock, "i2c-hwclock") { const char *loc = of_get_property(hwclock, "hwctrl-location", NULL); if (loc == NULL) continue; if (strcmp(loc, "CPU CLOCK")) continue; if (!of_get_property(hwclock, "platform-get-frequency", NULL)) continue; break; } if (hwclock == NULL) { printk(KERN_ERR "cpufreq: Can't find i2c clock chip !\n"); rc = -ENODEV; goto bail; } DBG("cpufreq: i2c clock chip found: %s\n", hwclock->full_name); /* Now get all the platform functions */ pfunc_cpu_getfreq = pmf_find_function(hwclock, "get-frequency"); pfunc_cpu_setfreq_high = pmf_find_function(hwclock, "set-frequency-high"); pfunc_cpu_setfreq_low = pmf_find_function(hwclock, "set-frequency-low"); pfunc_slewing_done = pmf_find_function(hwclock, "slewing-done"); pfunc_cpu0_volt_high = pmf_find_function(hwclock, "set-voltage-high-0"); pfunc_cpu0_volt_low = pmf_find_function(hwclock, "set-voltage-low-0"); pfunc_cpu1_volt_high = pmf_find_function(hwclock, "set-voltage-high-1"); pfunc_cpu1_volt_low = pmf_find_function(hwclock, "set-voltage-low-1"); /* Check we have minimum requirements */ if (pfunc_cpu_getfreq == NULL || pfunc_cpu_setfreq_high == NULL || pfunc_cpu_setfreq_low == NULL || pfunc_slewing_done == NULL) { printk(KERN_ERR "cpufreq: Can't find platform functions !\n"); rc = -ENODEV; goto bail; } /* Check that we have complete sets */ if (pfunc_cpu0_volt_high == NULL || pfunc_cpu0_volt_low == NULL) { pmf_put_function(pfunc_cpu0_volt_high); pmf_put_function(pfunc_cpu0_volt_low); pfunc_cpu0_volt_high = pfunc_cpu0_volt_low = NULL; has_volt = 0; } if (!has_volt || pfunc_cpu1_volt_high == NULL || pfunc_cpu1_volt_low == NULL) { pmf_put_function(pfunc_cpu1_volt_high); pmf_put_function(pfunc_cpu1_volt_low); pfunc_cpu1_volt_high = pfunc_cpu1_volt_low = NULL; } /* Note: The device tree also contains a "platform-set-values" * function for which I haven't quite figured out the usage. It * might have to be called on init and/or wakeup, I'm not too sure * but things seem to work fine without it so far ... */ /* Get max frequency from device-tree */ valp = of_get_property(cpunode, "clock-frequency", NULL); if (!valp) { printk(KERN_ERR "cpufreq: Can't find CPU frequency !\n"); rc = -ENODEV; goto bail; } max_freq = (*valp)/1000; /* Now calculate reduced frequency by using the cpuid input freq * ratio. This requires 64 bits math unless we are willing to lose * some precision */ ih = *((u32 *)(eeprom + 0x10)); il = *((u32 *)(eeprom + 0x20)); /* Check for machines with no useful settings */ if (il == ih) { printk(KERN_WARNING "cpufreq: No low frequency mode available" " on this model !\n"); rc = -ENODEV; goto bail; } min_freq = 0; if (ih != 0 && il != 0) min_freq = (max_freq * il) / ih; /* Sanity check */ if (min_freq >= max_freq || min_freq < 1000) { printk(KERN_ERR "cpufreq: Can't calculate low frequency !\n"); rc = -ENXIO; goto bail; } g5_cpu_freqs[0].frequency = max_freq; g5_cpu_freqs[1].frequency = min_freq; /* Based on a measurement on Xserve G5, rounded up. */ transition_latency = 10 * NSEC_PER_MSEC; /* Set callbacks */ g5_switch_volt = g5_pfunc_switch_volt; g5_switch_freq = g5_pfunc_switch_freq; g5_query_freq = g5_pfunc_query_freq; /* Force apply current frequency to make sure everything is in * sync (voltage is right for example). Firmware may leave us with * a strange setting ... */ g5_switch_volt(CPUFREQ_HIGH); msleep(10); g5_pmode_cur = -1; g5_switch_freq(g5_query_freq()); printk(KERN_INFO "Registering G5 CPU frequency driver\n"); printk(KERN_INFO "Frequency method: i2c/pfunc, " "Voltage method: %s\n", has_volt ? "i2c/pfunc" : "none"); printk(KERN_INFO "Low: %d Mhz, High: %d Mhz, Cur: %d MHz\n", g5_cpu_freqs[1].frequency/1000, g5_cpu_freqs[0].frequency/1000, g5_cpu_freqs[g5_pmode_cur].frequency/1000); rc = cpufreq_register_driver(&g5_cpufreq_driver); bail: if (rc != 0) { pmf_put_function(pfunc_cpu_getfreq); pmf_put_function(pfunc_cpu_setfreq_high); pmf_put_function(pfunc_cpu_setfreq_low); pmf_put_function(pfunc_slewing_done); pmf_put_function(pfunc_cpu0_volt_high); pmf_put_function(pfunc_cpu0_volt_low); pmf_put_function(pfunc_cpu1_volt_high); pmf_put_function(pfunc_cpu1_volt_low); } of_node_put(hwclock); of_node_put(cpuid); of_node_put(cpunode); return rc; } static int __init g5_cpufreq_init(void) { struct device_node *cpunode; int rc = 0; /* Get first CPU node */ cpunode = of_cpu_device_node_get(0); if (cpunode == NULL) { pr_err("cpufreq: Can't find any CPU node\n"); return -ENODEV; } if (of_machine_is_compatible("PowerMac7,2") || of_machine_is_compatible("PowerMac7,3") || of_machine_is_compatible("RackMac3,1")) rc = g5_pm72_cpufreq_init(cpunode); #ifdef CONFIG_PMAC_SMU else rc = g5_neo2_cpufreq_init(cpunode); #endif /* CONFIG_PMAC_SMU */ return rc; } module_init(g5_cpufreq_init); MODULE_LICENSE("GPL");