From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/drivers/cpufreq/at32ap-cpufreq.c | 127 ++++++++++++++++++++++++++++++++ 1 file changed, 127 insertions(+) create mode 100644 kernel/drivers/cpufreq/at32ap-cpufreq.c (limited to 'kernel/drivers/cpufreq/at32ap-cpufreq.c') diff --git a/kernel/drivers/cpufreq/at32ap-cpufreq.c b/kernel/drivers/cpufreq/at32ap-cpufreq.c new file mode 100644 index 000000000..7b612c8bb --- /dev/null +++ b/kernel/drivers/cpufreq/at32ap-cpufreq.c @@ -0,0 +1,127 @@ +/* + * Copyright (C) 2004-2007 Atmel Corporation + * + * Based on MIPS implementation arch/mips/kernel/time.c + * Copyright 2001 MontaVista Software Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +/*#define DEBUG*/ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static struct cpufreq_frequency_table *freq_table; + +static unsigned int ref_freq; +static unsigned long loops_per_jiffy_ref; + +static int at32_set_target(struct cpufreq_policy *policy, unsigned int index) +{ + unsigned int old_freq, new_freq; + + old_freq = policy->cur; + new_freq = freq_table[index].frequency; + + if (!ref_freq) { + ref_freq = old_freq; + loops_per_jiffy_ref = boot_cpu_data.loops_per_jiffy; + } + + if (old_freq < new_freq) + boot_cpu_data.loops_per_jiffy = cpufreq_scale( + loops_per_jiffy_ref, ref_freq, new_freq); + clk_set_rate(policy->clk, new_freq * 1000); + if (new_freq < old_freq) + boot_cpu_data.loops_per_jiffy = cpufreq_scale( + loops_per_jiffy_ref, ref_freq, new_freq); + + return 0; +} + +static int at32_cpufreq_driver_init(struct cpufreq_policy *policy) +{ + unsigned int frequency, rate, min_freq; + struct clk *cpuclk; + int retval, steps, i; + + if (policy->cpu != 0) + return -EINVAL; + + cpuclk = clk_get(NULL, "cpu"); + if (IS_ERR(cpuclk)) { + pr_debug("cpufreq: could not get CPU clk\n"); + retval = PTR_ERR(cpuclk); + goto out_err; + } + + min_freq = (clk_round_rate(cpuclk, 1) + 500) / 1000; + frequency = (clk_round_rate(cpuclk, ~0UL) + 500) / 1000; + policy->cpuinfo.transition_latency = 0; + + /* + * AVR32 CPU frequency rate scales in power of two between maximum and + * minimum, also add space for the table end marker. + * + * Further validate that the frequency is usable, and append it to the + * frequency table. + */ + steps = fls(frequency / min_freq) + 1; + freq_table = kzalloc(steps * sizeof(struct cpufreq_frequency_table), + GFP_KERNEL); + if (!freq_table) { + retval = -ENOMEM; + goto out_err_put_clk; + } + + for (i = 0; i < (steps - 1); i++) { + rate = clk_round_rate(cpuclk, frequency * 1000) / 1000; + + if (rate != frequency) + freq_table[i].frequency = CPUFREQ_ENTRY_INVALID; + else + freq_table[i].frequency = frequency; + + frequency /= 2; + } + + policy->clk = cpuclk; + freq_table[steps - 1].frequency = CPUFREQ_TABLE_END; + + retval = cpufreq_table_validate_and_show(policy, freq_table); + if (!retval) { + printk("cpufreq: AT32AP CPU frequency driver\n"); + return 0; + } + + kfree(freq_table); +out_err_put_clk: + clk_put(cpuclk); +out_err: + return retval; +} + +static struct cpufreq_driver at32_driver = { + .name = "at32ap", + .init = at32_cpufreq_driver_init, + .verify = cpufreq_generic_frequency_table_verify, + .target_index = at32_set_target, + .get = cpufreq_generic_get, + .flags = CPUFREQ_STICKY, +}; + +static int __init at32_cpufreq_init(void) +{ + return cpufreq_register_driver(&at32_driver); +} +late_initcall(at32_cpufreq_init); -- cgit 1.2.3-korg