diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/platforms/Kconfig | 10 | ||||
| -rw-r--r-- | arch/powerpc/platforms/pasemi/Makefile | 1 | ||||
| -rw-r--r-- | arch/powerpc/platforms/pasemi/cpufreq.c | 307 | ||||
| -rw-r--r-- | arch/powerpc/platforms/pasemi/idle.c | 9 | ||||
| -rw-r--r-- | arch/powerpc/platforms/pasemi/pasemi.h | 8 |
5 files changed, 335 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/Kconfig b/arch/powerpc/platforms/Kconfig index ac62fa08f5e..102a44e3b7e 100644 --- a/arch/powerpc/platforms/Kconfig +++ b/arch/powerpc/platforms/Kconfig @@ -169,6 +169,16 @@ config CPU_FREQ_PMAC64 help This adds support for frequency switching on Apple iMac G5, and some of the more recent desktop G5 machines as well. + +config PPC_PASEMI_CPUFREQ + bool "Support for PA Semi PWRficient" + depends on CPU_FREQ && PPC_PASEMI + default y + select CPU_FREQ_TABLE + help + This adds the support for frequency switching on PA Semi + PWRficient processors. + endmenu config PPC601_SYNC_FIX diff --git a/arch/powerpc/platforms/pasemi/Makefile b/arch/powerpc/platforms/pasemi/Makefile index 7ffd43b43e0..2cd2a4f26a4 100644 --- a/arch/powerpc/platforms/pasemi/Makefile +++ b/arch/powerpc/platforms/pasemi/Makefile @@ -1,2 +1,3 @@ obj-y += setup.o pci.o time.o idle.o powersave.o iommu.o obj-$(CONFIG_PPC_PASEMI_MDIO) += gpio_mdio.o +obj-$(CONFIG_PPC_PASEMI_CPUFREQ) += cpufreq.o diff --git a/arch/powerpc/platforms/pasemi/cpufreq.c b/arch/powerpc/platforms/pasemi/cpufreq.c new file mode 100644 index 00000000000..4dd5c512f86 --- /dev/null +++ b/arch/powerpc/platforms/pasemi/cpufreq.c @@ -0,0 +1,307 @@ +/* + * Copyright (C) 2007 PA Semi, Inc + * + * Authors: Egor Martovetsky <egor@pasemi.com> + * Olof Johansson <olof@lixom.net> + * + * Maintained by: Olof Johansson <olof@lixom.net> + * + * Based on arch/powerpc/platforms/cell/cbe_cpufreq.c: + * (C) Copyright IBM Deutschland Entwicklung GmbH 2005 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2, or (at your option) + * any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + */ + +#include <linux/cpufreq.h> +#include <linux/timer.h> + +#include <asm/hw_irq.h> +#include <asm/io.h> +#include <asm/prom.h> + +#define SDCASR_REG 0x0100 +#define SDCASR_REG_STRIDE 0x1000 +#define SDCPWR_CFGA0_REG 0x0100 +#define SDCPWR_PWST0_REG 0x0000 +#define SDCPWR_GIZTIME_REG 0x0440 + +/* SDCPWR_GIZTIME_REG fields */ +#define SDCPWR_GIZTIME_GR 0x80000000 +#define SDCPWR_GIZTIME_LONGLOCK 0x000000ff + +/* Offset of ASR registers from SDC base */ +#define SDCASR_OFFSET 0x120000 + +static void __iomem *sdcpwr_mapbase; +static void __iomem *sdcasr_mapbase; + +static DEFINE_MUTEX(pas_switch_mutex); + +/* Current astate, is used when waking up from power savings on + * one core, in case the other core has switched states during + * the idle time. + */ +static int current_astate; + +/* We support 5(A0-A4) power states excluding turbo(A5-A6) modes */ +static struct cpufreq_frequency_table pas_freqs[] = { + {0, 0}, + {1, 0}, + {2, 0}, + {3, 0}, + {4, 0}, + {0, CPUFREQ_TABLE_END}, +}; + +static struct freq_attr *pas_cpu_freqs_attr[] = { + &cpufreq_freq_attr_scaling_available_freqs, + NULL, +}; + +/* + * hardware specific functions + */ + +static int get_astate_freq(int astate) +{ + u32 ret; + ret = in_le32(sdcpwr_mapbase + SDCPWR_CFGA0_REG + (astate * 0x10)); + + return ret & 0x3f; +} + +static int get_cur_astate(int cpu) +{ + u32 ret; + + ret = in_le32(sdcpwr_mapbase + SDCPWR_PWST0_REG); + ret = (ret >> (cpu * 4)) & 0x7; + + return ret; +} + +static int get_gizmo_latency(void) +{ + u32 giztime, ret; + + giztime = in_le32(sdcpwr_mapbase + SDCPWR_GIZTIME_REG); + + /* just provide the upper bound */ + if (giztime & SDCPWR_GIZTIME_GR) + ret = (giztime & SDCPWR_GIZTIME_LONGLOCK) * 128000; + else + ret = (giztime & SDCPWR_GIZTIME_LONGLOCK) * 1000; + + return ret; +} + +static void set_astate(int cpu, unsigned int astate) +{ + u64 flags; + + /* Return if called before init has run */ + if (unlikely(!sdcasr_mapbase)) + return; + + local_irq_save(flags); + + out_le32(sdcasr_mapbase + SDCASR_REG + SDCASR_REG_STRIDE*cpu, astate); + + local_irq_restore(flags); +} + +void restore_astate(int cpu) +{ + set_astate(cpu, current_astate); +} + +/* + * cpufreq functions + */ + +static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy) +{ + u32 *max_freq; + int i, cur_astate; + struct resource res; + struct device_node *cpu, *dn; + int err = -ENODEV; + + cpu = of_get_cpu_node(policy->cpu, NULL); + + if (!cpu) + goto out; + + dn = of_find_compatible_node(NULL, "sdc", "1682m-sdc"); + if (!dn) + goto out; + err = of_address_to_resource(dn, 0, &res); + of_node_put(dn); + if (err) + goto out; + sdcasr_mapbase = ioremap(res.start + SDCASR_OFFSET, 0x2000); + if (!sdcasr_mapbase) { + err = -EINVAL; + goto out; + } + + dn = of_find_compatible_node(NULL, "gizmo", "1682m-gizmo"); + if (!dn) { + err = -ENODEV; + goto out_unmap_sdcasr; + } + err = of_address_to_resource(dn, 0, &res); + of_node_put(dn); + if (err) + goto out_unmap_sdcasr; + sdcpwr_mapbase = ioremap(res.start, 0x1000); + if (!sdcpwr_mapbase) { + err = -EINVAL; + goto out_unmap_sdcasr; + } + + pr_debug("init cpufreq on CPU %d\n", policy->cpu); + + max_freq = (u32*) get_property(cpu, "clock-frequency", NULL); + if (!max_freq) { + err = -EINVAL; + goto out_unmap_sdcpwr; + } + + /* we need the freq in kHz */ + *max_freq /= 1000; + + pr_debug("max clock-frequency is at %u kHz\n", *max_freq); + pr_debug("initializing frequency table\n"); + + /* initialize frequency table */ + for (i=0; pas_freqs[i].frequency!=CPUFREQ_TABLE_END; i++) { + pas_freqs[i].frequency = get_astate_freq(pas_freqs[i].index) * 100000; + pr_debug("%d: %d\n", i, pas_freqs[i].frequency); + } + + policy->governor = CPUFREQ_DEFAULT_GOVERNOR; + + policy->cpuinfo.transition_latency = get_gizmo_latency(); + + cur_astate = get_cur_astate(policy->cpu); + pr_debug("current astate is at %d\n",cur_astate); + + policy->cur = pas_freqs[cur_astate].frequency; + policy->cpus = cpu_online_map; + + cpufreq_frequency_table_get_attr(pas_freqs, policy->cpu); + + /* this ensures that policy->cpuinfo_min and policy->cpuinfo_max + * are set correctly + */ + return cpufreq_frequency_table_cpuinfo(policy, pas_freqs); + +out_unmap_sdcpwr: + iounmap(sdcpwr_mapbase); + +out_unmap_sdcasr: + iounmap(sdcasr_mapbase); +out: + return err; +} + +static int pas_cpufreq_cpu_exit(struct cpufreq_policy *policy) +{ + if (sdcasr_mapbase) + iounmap(sdcasr_mapbase); + if (sdcpwr_mapbase) + iounmap(sdcpwr_mapbase); + + cpufreq_frequency_table_put_attr(policy->cpu); + return 0; +} + +static int pas_cpufreq_verify(struct cpufreq_policy *policy) +{ + return cpufreq_frequency_table_verify(policy, pas_freqs); +} + +static int pas_cpufreq_target(struct cpufreq_policy *policy, + unsigned int target_freq, + unsigned int relation) +{ + struct cpufreq_freqs freqs; + int pas_astate_new; + int i; + + cpufreq_frequency_table_target(policy, + pas_freqs, + target_freq, + relation, + &pas_astate_new); + + freqs.old = policy->cur; + freqs.new = pas_freqs[pas_astate_new].frequency; + freqs.cpu = policy->cpu; + + mutex_lock(&pas_switch_mutex); + cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); + + pr_debug("setting frequency for cpu %d to %d kHz, 1/%d of max frequency\n", + policy->cpu, + pas_freqs[pas_astate_new].frequency, + pas_freqs[pas_astate_new].index); + + current_astate = pas_astate_new; + + for_each_online_cpu(i) + set_astate(i, pas_astate_new); + + cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); + mutex_unlock(&pas_switch_mutex); + + return 0; +} + +static struct cpufreq_driver pas_cpufreq_driver = { + .name = "pas-cpufreq", + .owner = THIS_MODULE, + .flags = CPUFREQ_CONST_LOOPS, + .init = pas_cpufreq_cpu_init, + .exit = pas_cpufreq_cpu_exit, + .verify = pas_cpufreq_verify, + .target = pas_cpufreq_target, + .attr = pas_cpu_freqs_attr, +}; + +/* + * module init and destoy + */ + +static int __init pas_cpufreq_init(void) +{ + if (!machine_is_compatible("PA6T-1682M")) + return -ENODEV; + + return cpufreq_register_driver(&pas_cpufreq_driver); +} + +static void __exit pas_cpufreq_exit(void) +{ + cpufreq_unregister_driver(&pas_cpufreq_driver); +} + +module_init(pas_cpufreq_init); +module_exit(pas_cpufreq_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>, Olof Johansson <olof@lixom.net>"); diff --git a/arch/powerpc/platforms/pasemi/idle.c b/arch/powerpc/platforms/pasemi/idle.c index 1ca3ff38159..5985ce0c5c4 100644 --- a/arch/powerpc/platforms/pasemi/idle.c +++ b/arch/powerpc/platforms/pasemi/idle.c @@ -61,6 +61,10 @@ static int pasemi_system_reset_exception(struct pt_regs *regs) /* do system reset */ return 0; } + + /* Set higher astate since we come out of power savings at 0 */ + restore_astate(hard_smp_processor_id()); + /* everything handled */ regs->msr |= MSR_RI; return 1; @@ -68,6 +72,11 @@ static int pasemi_system_reset_exception(struct pt_regs *regs) void __init pasemi_idle_init(void) { +#ifndef CONFIG_PPC_PASEMI_CPUFREQ + printk(KERN_WARNING "No cpufreq driver, powersavings modes disabled\n"); + current_mode = 0; +#endif + ppc_md.system_reset_exception = pasemi_system_reset_exception; ppc_md.power_save = modes[current_mode].entry; printk(KERN_INFO "Using PA6T idle loop (%s)\n", modes[current_mode].name); diff --git a/arch/powerpc/platforms/pasemi/pasemi.h b/arch/powerpc/platforms/pasemi/pasemi.h index 2d3927e6edb..be849549761 100644 --- a/arch/powerpc/platforms/pasemi/pasemi.h +++ b/arch/powerpc/platforms/pasemi/pasemi.h @@ -14,6 +14,14 @@ extern void __init pasemi_idle_init(void); extern void idle_spin(void); extern void idle_doze(void); +/* Restore astate to last set */ +#ifdef CONFIG_PPC_PASEMI_CPUFREQ +extern void restore_astate(int cpu); +#else +static inline void restore_astate(int cpu) +{ +} +#endif #endif /* _PASEMI_PASEMI_H */ |