[mirror_ubuntu-bionic-kernel.git] / drivers / cpufreq / cris-artpec3-cpufreq.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/init.h>
#include <linux/module.h>
#include <linux/cpufreq.h>
#include <hwregs/reg_map.h>
#include <hwregs/reg_rdwr.h>
#include <hwregs/clkgen_defs.h>
#include <hwregs/ddr2_defs.h>

static int
cris_sdram_freq_notifier(struct notifier_block *nb, unsigned long val,
	void *data);

static struct notifier_block cris_sdram_freq_notifier_block = {
	.notifier_call = cris_sdram_freq_notifier
};

static struct cpufreq_frequency_table cris_freq_table[] = {
	{0, 0x01, 6000},
	{0, 0x02, 200000},
	{0, 0, CPUFREQ_TABLE_END},
};

static unsigned int cris_freq_get_cpu_frequency(unsigned int cpu)
{
	reg_clkgen_rw_clk_ctrl clk_ctrl;
	clk_ctrl = REG_RD(clkgen, regi_clkgen, rw_clk_ctrl);
	return clk_ctrl.pll ? 200000 : 6000;
}

static int cris_freq_target(struct cpufreq_policy *policy, unsigned int state)
{
	reg_clkgen_rw_clk_ctrl clk_ctrl;
	clk_ctrl = REG_RD(clkgen, regi_clkgen, rw_clk_ctrl);

	local_irq_disable();

	/* Even though we may be SMP they will share the same clock
	 * so all settings are made on CPU0. */
	if (cris_freq_table[state].frequency == 200000)
		clk_ctrl.pll = 1;
	else
		clk_ctrl.pll = 0;
	REG_WR(clkgen, regi_clkgen, rw_clk_ctrl, clk_ctrl);

	local_irq_enable();

	return 0;
}

static int cris_freq_cpu_init(struct cpufreq_policy *policy)
{
	return cpufreq_generic_init(policy, cris_freq_table, 1000000);
}

static struct cpufreq_driver cris_freq_driver = {
	.get	= cris_freq_get_cpu_frequency,
	.verify	= cpufreq_generic_frequency_table_verify,
	.target_index = cris_freq_target,
	.init	= cris_freq_cpu_init,
	.name	= "cris_freq",
	.attr	= cpufreq_generic_attr,
};

static int __init cris_freq_init(void)
{
	int ret;
	ret = cpufreq_register_driver(&cris_freq_driver);
	cpufreq_register_notifier(&cris_sdram_freq_notifier_block,
		CPUFREQ_TRANSITION_NOTIFIER);
	return ret;
}

static int
cris_sdram_freq_notifier(struct notifier_block *nb, unsigned long val,
	void *data)
{
	int i;
	struct cpufreq_freqs *freqs = data;
	if (val == CPUFREQ_PRECHANGE) {
		reg_ddr2_rw_cfg cfg =
		  REG_RD(ddr2, regi_ddr2_ctrl, rw_cfg);
		cfg.ref_interval = (freqs->new == 200000 ? 1560 : 46);

		if (freqs->new == 200000)
			for (i = 0; i < 50000; i++);
		REG_WR(bif_core, regi_bif_core, rw_sdram_timing, timing);
	}
	return 0;
}


module_init(cris_freq_init);
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
035e111f JN	2	#include <linux/init.h>
	3	#include <linux/module.h>
	4	#include <linux/cpufreq.h>
	5	#include <hwregs/reg_map.h>
	6	#include <hwregs/reg_rdwr.h>
	7	#include <hwregs/clkgen_defs.h>
	8	#include <hwregs/ddr2_defs.h>
	9
	10	static int
	11	cris_sdram_freq_notifier(struct notifier_block *nb, unsigned long val,
	12	void *data);
	13
	14	static struct notifier_block cris_sdram_freq_notifier_block = {
	15	.notifier_call = cris_sdram_freq_notifier
	16	};
	17
	18	static struct cpufreq_frequency_table cris_freq_table[] = {
7f4b0461 VK	19	{0, 0x01, 6000},
	20	{0, 0x02, 200000},
	21	{0, 0, CPUFREQ_TABLE_END},
035e111f JN	22	};
	23
	24	static unsigned int cris_freq_get_cpu_frequency(unsigned int cpu)
	25	{
	26	reg_clkgen_rw_clk_ctrl clk_ctrl;
	27	clk_ctrl = REG_RD(clkgen, regi_clkgen, rw_clk_ctrl);
	28	return clk_ctrl.pll ? 200000 : 6000;
	29	}
	30
9c0ebcf7	31	static int cris_freq_target(struct cpufreq_policy *policy, unsigned int state)
035e111f	32	{
035e111f JN	33	reg_clkgen_rw_clk_ctrl clk_ctrl;
	34	clk_ctrl = REG_RD(clkgen, regi_clkgen, rw_clk_ctrl);
	35
035e111f JN	36	local_irq_disable();
	37
	38	/* Even though we may be SMP they will share the same clock
	39	* so all settings are made on CPU0. */
	40	if (cris_freq_table[state].frequency == 200000)
	41	clk_ctrl.pll = 1;
	42	else
	43	clk_ctrl.pll = 0;
	44	REG_WR(clkgen, regi_clkgen, rw_clk_ctrl, clk_ctrl);
	45
	46	local_irq_enable();
	47
035e111f JN	48	return 0;
	49	}
	50
	51	static int cris_freq_cpu_init(struct cpufreq_policy *policy)
	52	{
1870e111	53	return cpufreq_generic_init(policy, cris_freq_table, 1000000);
035e111f JN	54	}
035e111f JN	55
035e111f JN	56	static struct cpufreq_driver cris_freq_driver = {
035e111f JN	57	.get = cris_freq_get_cpu_frequency,
361db10f	58	.verify = cpufreq_generic_frequency_table_verify,
9c0ebcf7	59	.target_index = cris_freq_target,
035e111f	60	.init = cris_freq_cpu_init,
035e111f	61	.name = "cris_freq",
361db10f	62	.attr = cpufreq_generic_attr,
035e111f JN	63	};
	64
	65	static int __init cris_freq_init(void)
	66	{
	67	int ret;
	68	ret = cpufreq_register_driver(&cris_freq_driver);
	69	cpufreq_register_notifier(&cris_sdram_freq_notifier_block,
	70	CPUFREQ_TRANSITION_NOTIFIER);
	71	return ret;
	72	}
	73
	74	static int
	75	cris_sdram_freq_notifier(struct notifier_block *nb, unsigned long val,
	76	void *data)
	77	{
	78	int i;
	79	struct cpufreq_freqs *freqs = data;
	80	if (val == CPUFREQ_PRECHANGE) {
	81	reg_ddr2_rw_cfg cfg =
	82	REG_RD(ddr2, regi_ddr2_ctrl, rw_cfg);
	83	cfg.ref_interval = (freqs->new == 200000 ? 1560 : 46);
	84
	85	if (freqs->new == 200000)
	86	for (i = 0; i < 50000; i++);
	87	REG_WR(bif_core, regi_bif_core, rw_sdram_timing, timing);
	88	}
	89	return 0;
	90	}
	91
	92
	93	module_init(cris_freq_init);