[CPUFREQ] AMD Elan SC520 cpufreq driver. From: Sean Young Signed-off-by: Dave Jones diff -Nru a/Documentation/cpu-freq/user-guide.txt b/Documentation/cpu-freq/user-guide.txt --- a/Documentation/cpu-freq/user-guide.txt 2005-04-28 16:19:36 -04:00 +++ b/Documentation/cpu-freq/user-guide.txt 2005-04-28 16:19:36 -04:00 @@ -53,6 +53,7 @@ The following processors for the x86 architecture are supported by cpufreq: AMD Elan - SC400, SC410 +AMD Elan - SC520 AMD mobile K6-2+ AMD mobile K6-3+ AMD mobile Duron diff -Nru a/arch/i386/kernel/cpu/cpufreq/Kconfig b/arch/i386/kernel/cpu/cpufreq/Kconfig --- a/arch/i386/kernel/cpu/cpufreq/Kconfig 2005-04-28 16:19:36 -04:00 +++ b/arch/i386/kernel/cpu/cpufreq/Kconfig 2005-04-28 16:19:36 -04:00 @@ -23,7 +23,7 @@ If in doubt, say N. config ELAN_CPUFREQ - tristate "AMD Elan" + tristate "AMD Elan SC500 and SC410" select CPU_FREQ_TABLE depends on X86_ELAN ---help--- @@ -37,6 +37,18 @@ For details, take a look at . If in doubt, say N. + +config SC520_CPUFREQ + tristate "AMD Elan SC520" + select CPU_FREQ_TABLE + depends on X86_ELAN + ---help--- + This adds the CPUFreq driver for AMD Elan SC520 processor. + + For details, take a look at . + + If in doubt, say N. + config X86_POWERNOW_K6 tristate "AMD Mobile K6-2/K6-3 PowerNow!" diff -Nru a/arch/i386/kernel/cpu/cpufreq/Makefile b/arch/i386/kernel/cpu/cpufreq/Makefile --- a/arch/i386/kernel/cpu/cpufreq/Makefile 2005-04-28 16:19:36 -04:00 +++ b/arch/i386/kernel/cpu/cpufreq/Makefile 2005-04-28 16:19:36 -04:00 @@ -3,6 +3,7 @@ obj-$(CONFIG_X86_POWERNOW_K8) += powernow-k8.o obj-$(CONFIG_X86_LONGHAUL) += longhaul.o obj-$(CONFIG_ELAN_CPUFREQ) += elanfreq.o +obj-$(CONFIG_SC520_CPUFREQ) += sc520_freq.o obj-$(CONFIG_X86_LONGRUN) += longrun.o obj-$(CONFIG_X86_GX_SUSPMOD) += gx-suspmod.o obj-$(CONFIG_X86_SPEEDSTEP_ICH) += speedstep-ich.o diff -Nru a/arch/i386/kernel/cpu/cpufreq/sc520_freq.c b/arch/i386/kernel/cpu/cpufreq/sc520_freq.c --- /dev/null Wed Dec 31 16:00:00 196900 +++ b/arch/i386/kernel/cpu/cpufreq/sc520_freq.c 2005-04-28 16:19:36 -04:00 @@ -0,0 +1,179 @@ +/* + * sc520_freq.c: cpufreq driver for the AMD Elan sc520 + * + * Copyright (C) 2005 Sean Young + * + * 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 of the License, or (at your option) any later version. + * + * Based on elanfreq.c + * + * 2005-03-30: - initial revision + */ + +#include +#include +#include + +#include +#include +#include + +#include +#include +#include + +#define MMCR_BASE 0xfffef000 /* The default base address */ +#define OFFS_CPUCTL 0x2 /* CPU Control Register */ + +static __u8 __iomem *cpuctl; + +static struct cpufreq_frequency_table sc520_freq_table[] = { + {0x01, 100000}, + {0x02, 133000}, + {0, CPUFREQ_TABLE_END}, +}; + +static unsigned int sc520_freq_get_cpu_frequency(unsigned int cpu) +{ + u8 clockspeed_reg = *cpuctl; + + switch (clockspeed_reg & 0x03) { + default: + printk(KERN_ERR "sc520_freq: error: cpuctl register has unexpected value %02x\n", clockspeed_reg); + case 0x01: + return 100000; + case 0x02: + return 133000; + } +} + +static void sc520_freq_set_cpu_state (unsigned int state) +{ + + struct cpufreq_freqs freqs; + + freqs.old = sc520_freq_get_cpu_frequency(0); + freqs.new = sc520_freq_table[state].frequency; + freqs.cpu = 0; /* AMD Elan is UP */ + + cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); + + printk(KERN_INFO "sc520_freq: attempting to set frequency to %i kHz\n", + sc520_freq_table[state].frequency); + + *cpuctl = sc520_freq_table[state].index; + + cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); +}; + +static int sc520_freq_verify (struct cpufreq_policy *policy) +{ + return cpufreq_frequency_table_verify(policy, &sc520_freq_table[0]); +} + +static int sc520_freq_target (struct cpufreq_policy *policy, + unsigned int target_freq, + unsigned int relation) +{ + unsigned int newstate = 0; + + if (cpufreq_frequency_table_target(policy, sc520_freq_table, target_freq, relation, &newstate)) + return -EINVAL; + + sc520_freq_set_cpu_state(newstate); + + return 0; +} + + +/* + * Module init and exit code + */ + +static int sc520_freq_cpu_init(struct cpufreq_policy *policy) +{ + struct cpuinfo_x86 *c = cpu_data; + int result; + + /* capability check */ + if (c->x86_vendor != X86_VENDOR_AMD || + c->x86 != 4 || c->x86_model != 9) + return -ENODEV; + + /* cpuinfo and default policy values */ + policy->governor = CPUFREQ_DEFAULT_GOVERNOR; + policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL; + policy->cur = sc520_freq_get_cpu_frequency(0); + + result = cpufreq_frequency_table_cpuinfo(policy, sc520_freq_table); + if (result) + return (result); + + cpufreq_frequency_table_get_attr(sc520_freq_table, policy->cpu); + + return 0; +} + + +static int sc520_freq_cpu_exit(struct cpufreq_policy *policy) +{ + cpufreq_frequency_table_put_attr(policy->cpu); + return 0; +} + + +static struct freq_attr* sc520_freq_attr[] = { + &cpufreq_freq_attr_scaling_available_freqs, + NULL, +}; + + +static struct cpufreq_driver sc520_freq_driver = { + .get = sc520_freq_get_cpu_frequency, + .verify = sc520_freq_verify, + .target = sc520_freq_target, + .init = sc520_freq_cpu_init, + .exit = sc520_freq_cpu_exit, + .name = "sc520_freq", + .owner = THIS_MODULE, + .attr = sc520_freq_attr, +}; + + +static int __init sc520_freq_init(void) +{ + struct cpuinfo_x86 *c = cpu_data; + + /* Test if we have the right hardware */ + if (c->x86_vendor != X86_VENDOR_AMD || + c->x86 != 4 || c->x86_model != 9) { + printk(KERN_INFO "sc520_freq: error: no Elan SC520 processor found!\n"); + return -ENODEV; + } + cpuctl = ioremap((unsigned long)(MMCR_BASE + OFFS_CPUCTL), 1); + if(!cpuctl) { + printk(KERN_ERR "sc520_freq: error: failed to remap memory\n"); + return -ENOMEM; + } + + return cpufreq_register_driver(&sc520_freq_driver); +} + + +static void __exit sc520_freq_exit(void) +{ + cpufreq_unregister_driver(&sc520_freq_driver); + iounmap(cpuctl); +} + + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Sean Young "); +MODULE_DESCRIPTION("cpufreq driver for AMD's Elan sc520 CPU"); + +module_init(sc520_freq_init); +module_exit(sc520_freq_exit); +