[POWERPC] pasemi: Cpufreq driver (2e0c3370) · Commits · e / devices / android_kernel_teracube_2e

arch/powerpc/platforms/Kconfig

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Original line number	Diff line number	Diff line
		@@ -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

arch/powerpc/platforms/pasemi/Makefile

+1 −0

Original line number	Diff line number	Diff line
		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

arch/powerpc/platforms/pasemi/cpufreq.c

0 → 100644

+307 −0

Original line number	Diff line number	Diff line
		/*
		* 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>");

arch/powerpc/platforms/pasemi/idle.c

+9 −0

Original line number	Diff line number	Diff line
		@@ -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);

arch/powerpc/platforms/pasemi/pasemi.h

+8 −0

Original line number	Diff line number	Diff line
		@@ -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 */