cpufreq: ppc_cbe: Remove powerpc Cell driver

# SPDX-License-Identifier: GPL-2.0-only

config CPU_FREQ_CBE

	tristate "CBE frequency scaling"

	depends on CBE_RAS && PPC_CELL

	default m

	help

	  This adds the cpufreq driver for Cell BE processors.

	  For details, take a look at <file:Documentation/cpu-freq/>.

	  If you don't have such processor, say N

config CPU_FREQ_CBE_PMI

	bool "CBE frequency scaling using PMI interface"

	depends on CPU_FREQ_CBE

	default n

	help

	  Select this, if you want to use the PMI interface to switch

	  frequencies. Using PMI, the processor will not only be able to run at

	  lower speed, but also at lower core voltage.

config CPU_FREQ_PMAC

	bool "Support for Apple PowerBooks"

	depends on ADB_PMU && PPC32

##################################################################################

# PowerPC platform drivers

obj-$(CONFIG_CPU_FREQ_CBE)		+= ppc-cbe-cpufreq.o

ppc-cbe-cpufreq-y			+= ppc_cbe_cpufreq_pervasive.o ppc_cbe_cpufreq.o

obj-$(CONFIG_CPU_FREQ_CBE_PMI)		+= ppc_cbe_cpufreq_pmi.o

obj-$(CONFIG_QORIQ_CPUFREQ)   		+= qoriq-cpufreq.o

obj-$(CONFIG_CPU_FREQ_PMAC)		+= pmac32-cpufreq.o

obj-$(CONFIG_CPU_FREQ_PMAC64)		+= pmac64-cpufreq.o

// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * cpufreq driver for the cell processor

 *

 * (C) Copyright IBM Deutschland Entwicklung GmbH 2005-2007

 *

 * Author: Christian Krafft <krafft@de.ibm.com>

 */

#include <linux/cpufreq.h>

#include <linux/module.h>

#include <linux/of.h>

#include <asm/machdep.h>

#include <asm/cell-regs.h>

#include "ppc_cbe_cpufreq.h"

/* the CBE supports an 8 step frequency scaling */

static struct cpufreq_frequency_table cbe_freqs[] = {

	{0, 1,	0},

	{0, 2,	0},

	{0, 3,	0},

	{0, 4,	0},

	{0, 5,	0},

	{0, 6,	0},

	{0, 8,	0},

	{0, 10,	0},

	{0, 0,	CPUFREQ_TABLE_END},

};

/*

 * hardware specific functions

 */

static int set_pmode(unsigned int cpu, unsigned int slow_mode)

{

	int rc;

	if (cbe_cpufreq_has_pmi)

		rc = cbe_cpufreq_set_pmode_pmi(cpu, slow_mode);

	else

		rc = cbe_cpufreq_set_pmode(cpu, slow_mode);

	pr_debug("register contains slow mode %d\n", cbe_cpufreq_get_pmode(cpu));

	return rc;

}

/*

 * cpufreq functions

 */

static int cbe_cpufreq_cpu_init(struct cpufreq_policy *policy)

{

	struct cpufreq_frequency_table *pos;

	const u32 *max_freqp;

	u32 max_freq;

	int cur_pmode;

	struct device_node *cpu;

	cpu = of_get_cpu_node(policy->cpu, NULL);

	if (!cpu)

		return -ENODEV;

	pr_debug("init cpufreq on CPU %d\n", policy->cpu);

	/*

	 * Let's check we can actually get to the CELL regs

	 */

	if (!cbe_get_cpu_pmd_regs(policy->cpu) ||

	    !cbe_get_cpu_mic_tm_regs(policy->cpu)) {

		pr_info("invalid CBE regs pointers for cpufreq\n");

		of_node_put(cpu);

		return -EINVAL;

	}

	max_freqp = of_get_property(cpu, "clock-frequency", NULL);

	of_node_put(cpu);

	if (!max_freqp)

		return -EINVAL;

	/* we need the freq in kHz */

	max_freq = *max_freqp / 1000;

	pr_debug("max clock-frequency is at %u kHz\n", max_freq);

	pr_debug("initializing frequency table\n");

	/* initialize frequency table */

	cpufreq_for_each_entry(pos, cbe_freqs) {

		pos->frequency = max_freq / pos->driver_data;

		pr_debug("%d: %d\n", (int)(pos - cbe_freqs), pos->frequency);

	}

	/* if DEBUG is enabled set_pmode() measures the latency

	 * of a transition */

	policy->cpuinfo.transition_latency = 25000;

	cur_pmode = cbe_cpufreq_get_pmode(policy->cpu);

	pr_debug("current pmode is at %d\n",cur_pmode);

	policy->cur = cbe_freqs[cur_pmode].frequency;

#ifdef CONFIG_SMP

	cpumask_copy(policy->cpus, cpu_sibling_mask(policy->cpu));

#endif

	policy->freq_table = cbe_freqs;

	cbe_cpufreq_pmi_policy_init(policy);

	return 0;

}

static void cbe_cpufreq_cpu_exit(struct cpufreq_policy *policy)

{

	cbe_cpufreq_pmi_policy_exit(policy);

}

static int cbe_cpufreq_target(struct cpufreq_policy *policy,

			      unsigned int cbe_pmode_new)

{

	pr_debug("setting frequency for cpu %d to %d kHz, " \

		 "1/%d of max frequency\n",

		 policy->cpu,

		 cbe_freqs[cbe_pmode_new].frequency,

		 cbe_freqs[cbe_pmode_new].driver_data);

	return set_pmode(policy->cpu, cbe_pmode_new);

}

static struct cpufreq_driver cbe_cpufreq_driver = {

	.verify		= cpufreq_generic_frequency_table_verify,

	.target_index	= cbe_cpufreq_target,

	.init		= cbe_cpufreq_cpu_init,

	.exit		= cbe_cpufreq_cpu_exit,

	.name		= "cbe-cpufreq",

	.flags		= CPUFREQ_CONST_LOOPS,

};

/*

 * module init and destoy

 */

static int __init cbe_cpufreq_init(void)

{

	int ret;

	if (!machine_is(cell))

		return -ENODEV;

	cbe_cpufreq_pmi_init();

	ret = cpufreq_register_driver(&cbe_cpufreq_driver);

	if (ret)

		cbe_cpufreq_pmi_exit();

	return ret;

}

static void __exit cbe_cpufreq_exit(void)

{

	cpufreq_unregister_driver(&cbe_cpufreq_driver);

	cbe_cpufreq_pmi_exit();

}

module_init(cbe_cpufreq_init);

module_exit(cbe_cpufreq_exit);

MODULE_DESCRIPTION("cpufreq driver for Cell BE processors");

MODULE_LICENSE("GPL");

MODULE_AUTHOR("Christian Krafft <krafft@de.ibm.com>");

/* SPDX-License-Identifier: GPL-2.0 */

/*

 * ppc_cbe_cpufreq.h

 *

 * This file contains the definitions used by the cbe_cpufreq driver.

 *

 * (C) Copyright IBM Deutschland Entwicklung GmbH 2005-2007

 *

 * Author: Christian Krafft <krafft@de.ibm.com>

 *

 */

#include <linux/cpufreq.h>

#include <linux/types.h>

int cbe_cpufreq_set_pmode(int cpu, unsigned int pmode);

int cbe_cpufreq_get_pmode(int cpu);

int cbe_cpufreq_set_pmode_pmi(int cpu, unsigned int pmode);

#if IS_ENABLED(CONFIG_CPU_FREQ_CBE_PMI)

extern bool cbe_cpufreq_has_pmi;

void cbe_cpufreq_pmi_policy_init(struct cpufreq_policy *policy);

void cbe_cpufreq_pmi_policy_exit(struct cpufreq_policy *policy);

void cbe_cpufreq_pmi_init(void);

void cbe_cpufreq_pmi_exit(void);

#else

#define cbe_cpufreq_has_pmi (0)

static inline void cbe_cpufreq_pmi_policy_init(struct cpufreq_policy *policy) {}

static inline void cbe_cpufreq_pmi_policy_exit(struct cpufreq_policy *policy) {}

static inline void cbe_cpufreq_pmi_init(void) {}

static inline void cbe_cpufreq_pmi_exit(void) {}

#endif

// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * pervasive backend for the cbe_cpufreq driver

 *

 * This driver makes use of the pervasive unit to

 * engage the desired frequency.

 *

 * (C) Copyright IBM Deutschland Entwicklung GmbH 2005-2007

 *

 * Author: Christian Krafft <krafft@de.ibm.com>

 */

#include <linux/io.h>

#include <linux/kernel.h>

#include <linux/time.h>

#include <asm/machdep.h>

#include <asm/hw_irq.h>

#include <asm/cell-regs.h>

#include "ppc_cbe_cpufreq.h"

/* to write to MIC register */

static u64 MIC_Slow_Fast_Timer_table[] = {

	[0 ... 7] = 0x007fc00000000000ull,

};

/* more values for the MIC */

static u64 MIC_Slow_Next_Timer_table[] = {

	0x0000240000000000ull,

	0x0000268000000000ull,

	0x000029C000000000ull,

	0x00002D0000000000ull,

	0x0000300000000000ull,

	0x0000334000000000ull,

	0x000039C000000000ull,

	0x00003FC000000000ull,

};

int cbe_cpufreq_set_pmode(int cpu, unsigned int pmode)

{

	struct cbe_pmd_regs __iomem *pmd_regs;

	struct cbe_mic_tm_regs __iomem *mic_tm_regs;

	unsigned long flags;

	u64 value;

#ifdef DEBUG

	long time;

#endif

	local_irq_save(flags);

	mic_tm_regs = cbe_get_cpu_mic_tm_regs(cpu);

	pmd_regs = cbe_get_cpu_pmd_regs(cpu);

#ifdef DEBUG

	time = jiffies;

#endif

	out_be64(&mic_tm_regs->slow_fast_timer_0, MIC_Slow_Fast_Timer_table[pmode]);

	out_be64(&mic_tm_regs->slow_fast_timer_1, MIC_Slow_Fast_Timer_table[pmode]);

	out_be64(&mic_tm_regs->slow_next_timer_0, MIC_Slow_Next_Timer_table[pmode]);

	out_be64(&mic_tm_regs->slow_next_timer_1, MIC_Slow_Next_Timer_table[pmode]);

	value = in_be64(&pmd_regs->pmcr);

	/* set bits to zero */

	value &= 0xFFFFFFFFFFFFFFF8ull;

	/* set bits to next pmode */

	value |= pmode;

	out_be64(&pmd_regs->pmcr, value);

#ifdef DEBUG

	/* wait until new pmode appears in status register */

	value = in_be64(&pmd_regs->pmsr) & 0x07;

	while (value != pmode) {

		cpu_relax();

		value = in_be64(&pmd_regs->pmsr) & 0x07;

	}

	time = jiffies  - time;

	time = jiffies_to_msecs(time);

	pr_debug("had to wait %lu ms for a transition using " \

		 "pervasive unit\n", time);

#endif

	local_irq_restore(flags);

	return 0;

}

int cbe_cpufreq_get_pmode(int cpu)

{

	int ret;

	struct cbe_pmd_regs __iomem *pmd_regs;

	pmd_regs = cbe_get_cpu_pmd_regs(cpu);

	ret = in_be64(&pmd_regs->pmsr) & 0x07;

	return ret;

}