diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/blackfin/mach-common/dpmc.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
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 <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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 <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/blackfin/mach-common/dpmc.c')
-rw-r--r-- | kernel/arch/blackfin/mach-common/dpmc.c | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/kernel/arch/blackfin/mach-common/dpmc.c b/kernel/arch/blackfin/mach-common/dpmc.c new file mode 100644 index 000000000..724a8c5f5 --- /dev/null +++ b/kernel/arch/blackfin/mach-common/dpmc.c @@ -0,0 +1,164 @@ +/* + * Copyright 2008 Analog Devices Inc. + * + * Licensed under the GPL-2 or later. + */ + +#include <linux/cdev.h> +#include <linux/device.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/types.h> +#include <linux/cpufreq.h> + +#include <asm/delay.h> +#include <asm/dpmc.h> + +#define DRIVER_NAME "bfin dpmc" + +struct bfin_dpmc_platform_data *pdata; + +/** + * bfin_set_vlev - Update VLEV field in VR_CTL Reg. + * Avoid BYPASS sequence + */ +static void bfin_set_vlev(unsigned int vlev) +{ + unsigned pll_lcnt; + + pll_lcnt = bfin_read_PLL_LOCKCNT(); + + bfin_write_PLL_LOCKCNT(1); + bfin_write_VR_CTL((bfin_read_VR_CTL() & ~VLEV) | vlev); + bfin_write_PLL_LOCKCNT(pll_lcnt); +} + +/** + * bfin_get_vlev - Get CPU specific VLEV from platform device data + */ +static unsigned int bfin_get_vlev(unsigned int freq) +{ + int i; + + if (!pdata) + goto err_out; + + freq >>= 16; + + for (i = 0; i < pdata->tabsize; i++) + if (freq <= (pdata->tuple_tab[i] & 0xFFFF)) + return pdata->tuple_tab[i] >> 16; + +err_out: + printk(KERN_WARNING "DPMC: No suitable CCLK VDDINT voltage pair found\n"); + return VLEV_120; +} + +#ifdef CONFIG_CPU_FREQ +# ifdef CONFIG_SMP +static void bfin_idle_this_cpu(void *info) +{ + unsigned long flags = 0; + unsigned long iwr0, iwr1, iwr2; + unsigned int cpu = smp_processor_id(); + + local_irq_save_hw(flags); + bfin_iwr_set_sup0(&iwr0, &iwr1, &iwr2); + + platform_clear_ipi(cpu, IRQ_SUPPLE_0); + SSYNC(); + asm("IDLE;"); + bfin_iwr_restore(iwr0, iwr1, iwr2); + + local_irq_restore_hw(flags); +} + +static void bfin_idle_cpu(void) +{ + smp_call_function(bfin_idle_this_cpu, NULL, 0); +} + +static void bfin_wakeup_cpu(void) +{ + unsigned int cpu; + unsigned int this_cpu = smp_processor_id(); + cpumask_t mask; + + cpumask_copy(&mask, cpu_online_mask); + cpumask_clear_cpu(this_cpu, &mask); + for_each_cpu(cpu, &mask) + platform_send_ipi_cpu(cpu, IRQ_SUPPLE_0); +} + +# else +static void bfin_idle_cpu(void) {} +static void bfin_wakeup_cpu(void) {} +# endif + +static int +vreg_cpufreq_notifier(struct notifier_block *nb, unsigned long val, void *data) +{ + struct cpufreq_freqs *freq = data; + + if (freq->cpu != CPUFREQ_CPU) + return 0; + + if (val == CPUFREQ_PRECHANGE && freq->old < freq->new) { + bfin_idle_cpu(); + bfin_set_vlev(bfin_get_vlev(freq->new)); + udelay(pdata->vr_settling_time); /* Wait until Volatge settled */ + bfin_wakeup_cpu(); + } else if (val == CPUFREQ_POSTCHANGE && freq->old > freq->new) { + bfin_idle_cpu(); + bfin_set_vlev(bfin_get_vlev(freq->new)); + bfin_wakeup_cpu(); + } + + return 0; +} + +static struct notifier_block vreg_cpufreq_notifier_block = { + .notifier_call = vreg_cpufreq_notifier +}; +#endif /* CONFIG_CPU_FREQ */ + +/** + * bfin_dpmc_probe - + * + */ +static int bfin_dpmc_probe(struct platform_device *pdev) +{ + if (pdev->dev.platform_data) + pdata = pdev->dev.platform_data; + else + return -EINVAL; + + return cpufreq_register_notifier(&vreg_cpufreq_notifier_block, + CPUFREQ_TRANSITION_NOTIFIER); +} + +/** + * bfin_dpmc_remove - + */ +static int bfin_dpmc_remove(struct platform_device *pdev) +{ + pdata = NULL; + return cpufreq_unregister_notifier(&vreg_cpufreq_notifier_block, + CPUFREQ_TRANSITION_NOTIFIER); +} + +struct platform_driver bfin_dpmc_device_driver = { + .probe = bfin_dpmc_probe, + .remove = bfin_dpmc_remove, + .driver = { + .name = DRIVER_NAME, + } +}; +module_platform_driver(bfin_dpmc_device_driver); + +MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); +MODULE_DESCRIPTION("cpu power management driver for Blackfin"); +MODULE_LICENSE("GPL"); |