// 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);