[linux-block.git] / drivers / cpufreq / pasemi-cpufreq.c

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

#include <linux/cpufreq.h>
#include <linux/timer.h>
#include <linux/module.h>
#include <linux/of_address.h>

#include <asm/hw_irq.h>
#include <asm/io.h>
#include <asm/time.h>
#include <asm/smp.h>

#include <platforms/pasemi/pasemi.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;

/* 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,	0},
	{0, 1,	0},
	{0, 2,	0},
	{0, 3,	0},
	{0, 4,	0},
	{0, 0,	CPUFREQ_TABLE_END},
};

/*
 * 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)
{
	unsigned long 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);
}

int check_astate(void)
{
	return get_cur_astate(hard_smp_processor_id());
}

void restore_astate(int cpu)
{
	set_astate(cpu, current_astate);
}

/*
 * cpufreq functions
 */

static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy)
{
	struct cpufreq_frequency_table *pos;
	const u32 *max_freqp;
	u32 max_freq;
	int cur_astate, idx;
	struct resource res;
	struct device_node *cpu, *dn;
	int err = -ENODEV;

	cpu = of_get_cpu_node(policy->cpu, NULL);
	if (!cpu)
		goto out;

	max_freqp = of_get_property(cpu, "clock-frequency", NULL);
	of_node_put(cpu);
	if (!max_freqp) {
		err = -EINVAL;
		goto out;
	}

	/* we need the freq in kHz */
	max_freq = *max_freqp / 1000;

	dn = of_find_compatible_node(NULL, NULL, "1682m-sdc");
	if (!dn)
		dn = of_find_compatible_node(NULL, NULL,
					     "pasemi,pwrficient-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, NULL, "1682m-gizmo");
	if (!dn)
		dn = of_find_compatible_node(NULL, NULL,
					     "pasemi,pwrficient-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);
	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_idx(pos, pas_freqs, idx) {
		pos->frequency = get_astate_freq(pos->driver_data) * 100000;
		pr_debug("%d: %d\n", idx, pos->frequency);
	}

	cur_astate = get_cur_astate(policy->cpu);
	pr_debug("current astate is at %d\n",cur_astate);

	policy->cur = pas_freqs[cur_astate].frequency;
	ppc_proc_freq = policy->cur * 1000ul;

	cpufreq_generic_init(policy, pas_freqs, get_gizmo_latency());
	return 0;

out_unmap_sdcasr:
	iounmap(sdcasr_mapbase);
out:
	return err;
}

static int pas_cpufreq_cpu_exit(struct cpufreq_policy *policy)
{
	/*
	 * We don't support CPU hotplug. Don't unmap after the system
	 * has already made it to a running state.
	 */
	if (system_state >= SYSTEM_RUNNING)
		return 0;

	if (sdcasr_mapbase)
		iounmap(sdcasr_mapbase);
	if (sdcpwr_mapbase)
		iounmap(sdcpwr_mapbase);

	return 0;
}

static int pas_cpufreq_target(struct cpufreq_policy *policy,
			      unsigned int pas_astate_new)
{
	int i;

	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].driver_data);

	current_astate = pas_astate_new;

	for_each_online_cpu(i)
		set_astate(i, pas_astate_new);

	ppc_proc_freq = pas_freqs[pas_astate_new].frequency * 1000ul;
	return 0;
}

static struct cpufreq_driver pas_cpufreq_driver = {
	.name		= "pas-cpufreq",
	.flags		= CPUFREQ_CONST_LOOPS,
	.init		= pas_cpufreq_cpu_init,
	.exit		= pas_cpufreq_cpu_exit,
	.verify		= cpufreq_generic_frequency_table_verify,
	.target_index	= pas_cpufreq_target,
	.attr		= cpufreq_generic_attr,
};

/*
 * module init and destoy
 */

static int __init pas_cpufreq_init(void)
{
	if (!of_machine_is_compatible("PA6T-1682M") &&
	    !of_machine_is_compatible("pasemi,pwrficient"))
		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>");
Commit	Line	Data
de6cc651	1	// SPDX-License-Identifier: GPL-2.0-or-later
2e0c3370 OJ	2	/*
	3	* Copyright (C) 2007 PA Semi, Inc
	4	*
	5	* Authors: Egor Martovetsky <egor@pasemi.com>
	6	* Olof Johansson <olof@lixom.net>
	7	*
	8	* Maintained by: Olof Johansson <olof@lixom.net>
	9	*
	10	* Based on arch/powerpc/platforms/cell/cbe_cpufreq.c:
	11	* (C) Copyright IBM Deutschland Entwicklung GmbH 2005
2e0c3370 OJ	12	*/
	13
	14	#include <linux/cpufreq.h>
	15	#include <linux/timer.h>
7dfe293c	16	#include <linux/module.h>
5af50730	17	#include <linux/of_address.h>
2e0c3370 OJ	18
	19	#include <asm/hw_irq.h>
	20	#include <asm/io.h>
2abb7019	21	#include <asm/time.h>
8b32bc03	22	#include <asm/smp.h>
2e0c3370	23
4a27aa9c LJ	24	#include <platforms/pasemi/pasemi.h>
4a27aa9c LJ	25
2e0c3370 OJ	26	#define SDCASR_REG 0x0100
	27	#define SDCASR_REG_STRIDE 0x1000
	28	#define SDCPWR_CFGA0_REG 0x0100
	29	#define SDCPWR_PWST0_REG 0x0000
	30	#define SDCPWR_GIZTIME_REG 0x0440
	31
	32	/* SDCPWR_GIZTIME_REG fields */
	33	#define SDCPWR_GIZTIME_GR 0x80000000
	34	#define SDCPWR_GIZTIME_LONGLOCK 0x000000ff
	35
	36	/* Offset of ASR registers from SDC base */
	37	#define SDCASR_OFFSET 0x120000
	38
	39	static void __iomem *sdcpwr_mapbase;
	40	static void __iomem *sdcasr_mapbase;
	41
2e0c3370 OJ	42	/* Current astate, is used when waking up from power savings on
	43	* one core, in case the other core has switched states during
	44	* the idle time.
	45	*/
	46	static int current_astate;
	47
	48	/* We support 5(A0-A4) power states excluding turbo(A5-A6) modes */
	49	static struct cpufreq_frequency_table pas_freqs[] = {
7f4b0461 VK	50	{0, 0, 0},
	51	{0, 1, 0},
	52	{0, 2, 0},
	53	{0, 3, 0},
	54	{0, 4, 0},
	55	{0, 0, CPUFREQ_TABLE_END},
2e0c3370 OJ	56	};
2e0c3370 OJ	57
2e0c3370 OJ	58	/*
	59	* hardware specific functions
	60	*/
	61
	62	static int get_astate_freq(int astate)
	63	{
	64	u32 ret;
	65	ret = in_le32(sdcpwr_mapbase + SDCPWR_CFGA0_REG + (astate * 0x10));
	66
	67	return ret & 0x3f;
	68	}
	69
	70	static int get_cur_astate(int cpu)
	71	{
	72	u32 ret;
	73
	74	ret = in_le32(sdcpwr_mapbase + SDCPWR_PWST0_REG);
	75	ret = (ret >> (cpu * 4)) & 0x7;
	76
	77	return ret;
	78	}
	79
	80	static int get_gizmo_latency(void)
	81	{
	82	u32 giztime, ret;
	83
	84	giztime = in_le32(sdcpwr_mapbase + SDCPWR_GIZTIME_REG);
	85
	86	/* just provide the upper bound */
	87	if (giztime & SDCPWR_GIZTIME_GR)
	88	ret = (giztime & SDCPWR_GIZTIME_LONGLOCK) * 128000;
	89	else
	90	ret = (giztime & SDCPWR_GIZTIME_LONGLOCK) * 1000;
	91
	92	return ret;
	93	}
	94
	95	static void set_astate(int cpu, unsigned int astate)
	96	{
ac3f6454	97	unsigned long flags;
2e0c3370 OJ	98
	99	/* Return if called before init has run */
	100	if (unlikely(!sdcasr_mapbase))
	101	return;
	102
	103	local_irq_save(flags);
	104
	105	out_le32(sdcasr_mapbase + SDCASR_REG + SDCASR_REG_STRIDE*cpu, astate);
	106
	107	local_irq_restore(flags);
	108	}
	109
8b32bc03 OJ	110	int check_astate(void)
	111	{
	112	return get_cur_astate(hard_smp_processor_id());
	113	}
	114
2e0c3370 OJ	115	void restore_astate(int cpu)
	116	{
	117	set_astate(cpu, current_astate);
	118	}
	119
	120	/*
	121	* cpufreq functions
	122	*/
	123
	124	static int pas_cpufreq_cpu_init(struct cpufreq_policy *policy)
	125	{
041526f9	126	struct cpufreq_frequency_table *pos;
12d371a6 SR	127	const u32 *max_freqp;
12d371a6 SR	128	u32 max_freq;
ffd81dcf	129	int cur_astate, idx;
2e0c3370 OJ	130	struct resource res;
	131	struct device_node cpu, dn;
	132	int err = -ENODEV;
	133
	134	cpu = of_get_cpu_node(policy->cpu, NULL);
e0a12445 WY	135	if (!cpu)
e0a12445 WY	136	goto out;
2e0c3370	137
e0a12445	138	max_freqp = of_get_property(cpu, "clock-frequency", NULL);
a9acc26b	139	of_node_put(cpu);
e0a12445 WY	140	if (!max_freqp) {
e0a12445 WY	141	err = -EINVAL;
2e0c3370	142	goto out;
e0a12445 WY	143	}
	144
	145	/* we need the freq in kHz */
	146	max_freq = *max_freqp / 1000;
2e0c3370	147
0d08a847 OJ	148	dn = of_find_compatible_node(NULL, NULL, "1682m-sdc");
	149	if (!dn)
	150	dn = of_find_compatible_node(NULL, NULL,
	151	"pasemi,pwrficient-sdc");
2e0c3370 OJ	152	if (!dn)
	153	goto out;
	154	err = of_address_to_resource(dn, 0, &res);
	155	of_node_put(dn);
	156	if (err)
	157	goto out;
	158	sdcasr_mapbase = ioremap(res.start + SDCASR_OFFSET, 0x2000);
	159	if (!sdcasr_mapbase) {
	160	err = -EINVAL;
	161	goto out;
	162	}
	163
0d08a847 OJ	164	dn = of_find_compatible_node(NULL, NULL, "1682m-gizmo");
	165	if (!dn)
	166	dn = of_find_compatible_node(NULL, NULL,
	167	"pasemi,pwrficient-gizmo");
2e0c3370 OJ	168	if (!dn) {
	169	err = -ENODEV;
	170	goto out_unmap_sdcasr;
	171	}
	172	err = of_address_to_resource(dn, 0, &res);
	173	of_node_put(dn);
	174	if (err)
	175	goto out_unmap_sdcasr;
	176	sdcpwr_mapbase = ioremap(res.start, 0x1000);
	177	if (!sdcpwr_mapbase) {
	178	err = -EINVAL;
	179	goto out_unmap_sdcasr;
	180	}
	181
	182	pr_debug("init cpufreq on CPU %d\n", policy->cpu);
12d371a6	183	pr_debug("max clock-frequency is at %u kHz\n", max_freq);
2e0c3370 OJ	184	pr_debug("initializing frequency table\n");
	185
	186	/* initialize frequency table */
ffd81dcf	187	cpufreq_for_each_entry_idx(pos, pas_freqs, idx) {
041526f9	188	pos->frequency = get_astate_freq(pos->driver_data) * 100000;
ffd81dcf	189	pr_debug("%d: %d\n", idx, pos->frequency);
2e0c3370 OJ	190	}
2e0c3370 OJ	191
2e0c3370 OJ	192	cur_astate = get_cur_astate(policy->cpu);
	193	pr_debug("current astate is at %d\n",cur_astate);
	194
	195	policy->cur = pas_freqs[cur_astate].frequency;
2abb7019 OJ	196	ppc_proc_freq = policy->cur * 1000ul;
2abb7019 OJ	197
c4dcc8a1 VK	198	cpufreq_generic_init(policy, pas_freqs, get_gizmo_latency());
c4dcc8a1 VK	199	return 0;
2e0c3370	200
2e0c3370 OJ	201	out_unmap_sdcasr:
	202	iounmap(sdcasr_mapbase);
	203	out:
	204	return err;
	205	}
	206
	207	static int pas_cpufreq_cpu_exit(struct cpufreq_policy *policy)
	208	{
72640d88 SR	209	/*
	210	* We don't support CPU hotplug. Don't unmap after the system
	211	* has already made it to a running state.
	212	*/
d04e31a2	213	if (system_state >= SYSTEM_RUNNING)
72640d88 SR	214	return 0;
72640d88 SR	215
2e0c3370 OJ	216	if (sdcasr_mapbase)
	217	iounmap(sdcasr_mapbase);
	218	if (sdcpwr_mapbase)
	219	iounmap(sdcpwr_mapbase);
	220
2e0c3370 OJ	221	return 0;
	222	}
	223
2e0c3370	224	static int pas_cpufreq_target(struct cpufreq_policy *policy,
9c0ebcf7	225	unsigned int pas_astate_new)
2e0c3370	226	{
2e0c3370 OJ	227	int i;
2e0c3370 OJ	228
2e0c3370 OJ	229	pr_debug("setting frequency for cpu %d to %d kHz, 1/%d of max frequency\n",
	230	policy->cpu,
	231	pas_freqs[pas_astate_new].frequency,
50701588	232	pas_freqs[pas_astate_new].driver_data);
2e0c3370 OJ	233
	234	current_astate = pas_astate_new;
	235
	236	for_each_online_cpu(i)
	237	set_astate(i, pas_astate_new);
	238
d4019f0a	239	ppc_proc_freq = pas_freqs[pas_astate_new].frequency * 1000ul;
2e0c3370 OJ	240	return 0;
	241	}
	242
	243	static struct cpufreq_driver pas_cpufreq_driver = {
	244	.name = "pas-cpufreq",
2e0c3370 OJ	245	.flags = CPUFREQ_CONST_LOOPS,
	246	.init = pas_cpufreq_cpu_init,
	247	.exit = pas_cpufreq_cpu_exit,
57174310	248	.verify = cpufreq_generic_frequency_table_verify,
9c0ebcf7	249	.target_index = pas_cpufreq_target,
57174310	250	.attr = cpufreq_generic_attr,
2e0c3370 OJ	251	};
	252
	253	/*
	254	* module init and destoy
	255	*/
	256
	257	static int __init pas_cpufreq_init(void)
	258	{
71a157e8 GL	259	if (!of_machine_is_compatible("PA6T-1682M") &&
71a157e8 GL	260	!of_machine_is_compatible("pasemi,pwrficient"))
2e0c3370 OJ	261	return -ENODEV;
	262
	263	return cpufreq_register_driver(&pas_cpufreq_driver);
	264	}
	265
	266	static void __exit pas_cpufreq_exit(void)
	267	{
	268	cpufreq_unregister_driver(&pas_cpufreq_driver);
	269	}
	270
	271	module_init(pas_cpufreq_init);
	272	module_exit(pas_cpufreq_exit);
	273
	274	MODULE_LICENSE("GPL");
	275	MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>, Olof Johansson <olof@lixom.net>");