diff options
Diffstat (limited to 'arch/arm/mach-imx/cpufreq.c')
-rw-r--r-- | arch/arm/mach-imx/cpufreq.c | 315 |
1 files changed, 0 insertions, 315 deletions
diff --git a/arch/arm/mach-imx/cpufreq.c b/arch/arm/mach-imx/cpufreq.c deleted file mode 100644 index 434b4ca0af6..00000000000 --- a/arch/arm/mach-imx/cpufreq.c +++ /dev/null @@ -1,315 +0,0 @@ -/* - * cpu.c: clock scaling for the iMX - * - * Copyright (C) 2000 2001, The Delft University of Technology - * Copyright (c) 2004 Sascha Hauer <sascha@saschahauer.de> - * Copyright (C) 2006 Inky Lung <ilung@cwlinux.com> - * Copyright (C) 2006 Pavel Pisa, PiKRON <ppisa@pikron.com> - * - * Based on SA1100 version written by: - * - Johan Pouwelse (J.A.Pouwelse@its.tudelft.nl): initial version - * - Erik Mouw (J.A.K.Mouw@its.tudelft.nl): - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - * - */ - -/*#define DEBUG*/ - -#include <linux/kernel.h> -#include <linux/types.h> -#include <linux/init.h> -#include <linux/cpufreq.h> -#include <linux/clk.h> -#include <linux/err.h> -#include <asm/system.h> - -#include <mach/hardware.h> - -#include "generic.h" - -#ifndef __val2mfld -#define __val2mfld(mask,val) (((mask)&~((mask)<<1))*(val)&(mask)) -#endif -#ifndef __mfld2val -#define __mfld2val(mask,val) (((val)&(mask))/((mask)&~((mask)<<1))) -#endif - -#define CR_920T_CLOCK_MODE 0xC0000000 -#define CR_920T_FASTBUS_MODE 0x00000000 -#define CR_920T_ASYNC_MODE 0xC0000000 - -static u32 mpctl0_at_boot; -static u32 bclk_div_at_boot; - -static struct clk *system_clk, *mcu_clk; - -static void imx_set_async_mode(void) -{ - adjust_cr(CR_920T_CLOCK_MODE, CR_920T_ASYNC_MODE); -} - -static void imx_set_fastbus_mode(void) -{ - adjust_cr(CR_920T_CLOCK_MODE, CR_920T_FASTBUS_MODE); -} - -static void imx_set_mpctl0(u32 mpctl0) -{ - unsigned long flags; - - if (mpctl0 == 0) { - local_irq_save(flags); - CSCR &= ~CSCR_MPEN; - local_irq_restore(flags); - return; - } - - local_irq_save(flags); - MPCTL0 = mpctl0; - CSCR |= CSCR_MPEN; - local_irq_restore(flags); -} - -/** - * imx_compute_mpctl - compute new PLL parameters - * @new_mpctl: pointer to location assigned by new PLL control register value - * @cur_mpctl: current PLL control register parameters - * @f_ref: reference source frequency Hz - * @freq: required frequency in Hz - * @relation: is one of %CPUFREQ_RELATION_L (supremum) - * and %CPUFREQ_RELATION_H (infimum) - */ -long imx_compute_mpctl(u32 *new_mpctl, u32 cur_mpctl, u32 f_ref, unsigned long freq, int relation) -{ - u32 mfi; - u32 mfn; - u32 mfd; - u32 pd; - unsigned long long ll; - long l; - long quot; - - /* Fdppl=2*Fref*(MFI+MFN/(MFD+1))/(PD+1) */ - /* PD=<0,15>, MFD=<1,1023>, MFI=<5,15> MFN=<0,1022> */ - - if (cur_mpctl) { - mfd = ((cur_mpctl >> 16) & 0x3ff) + 1; - pd = ((cur_mpctl >> 26) & 0xf) + 1; - } else { - pd=2; mfd=313; - } - - /* pd=2; mfd=313; mfi=8; mfn=183; */ - /* (MFI+MFN/(MFD)) = Fdppl / (2*Fref) * (PD); */ - - quot = (f_ref + (1 << 9)) >> 10; - l = (freq * pd + quot) / (2 * quot); - mfi = l >> 10; - mfn = ((l & ((1 << 10) - 1)) * mfd + (1 << 9)) >> 10; - - mfd -= 1; - pd -= 1; - - *new_mpctl = ((mfi & 0xf) << 10) | (mfn & 0x3ff) | ((mfd & 0x3ff) << 16) - | ((pd & 0xf) << 26); - - ll = 2 * (unsigned long long)f_ref * ( (mfi<<16) + (mfn<<16) / (mfd+1) ); - quot = (pd+1) * (1<<16); - ll += quot / 2; - do_div(ll, quot); - freq = ll; - - pr_debug(KERN_DEBUG "imx: new PLL parameters pd=%d mfd=%d mfi=%d mfn=%d, freq=%ld\n", - pd, mfd, mfi, mfn, freq); - - return freq; -} - - -static int imx_verify_speed(struct cpufreq_policy *policy) -{ - if (policy->cpu != 0) - return -EINVAL; - - cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, policy->cpuinfo.max_freq); - - return 0; -} - -static unsigned int imx_get_speed(unsigned int cpu) -{ - unsigned int freq; - unsigned int cr; - unsigned int cscr; - unsigned int bclk_div; - - if (cpu) - return 0; - - cscr = CSCR; - bclk_div = __mfld2val(CSCR_BCLK_DIV, cscr) + 1; - cr = get_cr(); - - if((cr & CR_920T_CLOCK_MODE) == CR_920T_FASTBUS_MODE) { - freq = clk_get_rate(system_clk); - freq = (freq + bclk_div/2) / bclk_div; - } else { - freq = clk_get_rate(mcu_clk); - if (cscr & CSCR_MPU_PRESC) - freq /= 2; - } - - freq = (freq + 500) / 1000; - - return freq; -} - -static int imx_set_target(struct cpufreq_policy *policy, - unsigned int target_freq, - unsigned int relation) -{ - struct cpufreq_freqs freqs; - u32 mpctl0 = 0; - u32 cscr; - unsigned long flags; - long freq; - long sysclk; - unsigned int bclk_div = bclk_div_at_boot; - - /* - * Some governors do not respects CPU and policy lower limits - * which leads to bad things (division by zero etc), ensure - * that such things do not happen. - */ - if(target_freq < policy->cpuinfo.min_freq) - target_freq = policy->cpuinfo.min_freq; - - if(target_freq < policy->min) - target_freq = policy->min; - - freq = target_freq * 1000; - - pr_debug(KERN_DEBUG "imx: requested frequency %ld Hz, mpctl0 at boot 0x%08x\n", - freq, mpctl0_at_boot); - - sysclk = clk_get_rate(system_clk); - - if (freq > sysclk / bclk_div_at_boot + 1000000) { - freq = imx_compute_mpctl(&mpctl0, mpctl0_at_boot, CLK32 * 512, freq, relation); - if (freq < 0) { - printk(KERN_WARNING "imx: target frequency %ld Hz cannot be set\n", freq); - return -EINVAL; - } - } else { - if(freq + 1000 < sysclk) { - if (relation == CPUFREQ_RELATION_L) - bclk_div = (sysclk - 1000) / freq; - else - bclk_div = (sysclk + freq + 1000) / freq; - - if(bclk_div > 16) - bclk_div = 16; - if(bclk_div < bclk_div_at_boot) - bclk_div = bclk_div_at_boot; - } - freq = (sysclk + bclk_div / 2) / bclk_div; - } - - freqs.old = imx_get_speed(0); - freqs.new = (freq + 500) / 1000; - freqs.cpu = 0; - freqs.flags = 0; - - cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); - - local_irq_save(flags); - - imx_set_fastbus_mode(); - - imx_set_mpctl0(mpctl0); - - cscr = CSCR; - cscr &= ~CSCR_BCLK_DIV; - cscr |= __val2mfld(CSCR_BCLK_DIV, bclk_div - 1); - CSCR = cscr; - - if(mpctl0) { - CSCR |= CSCR_MPLL_RESTART; - - /* Wait until MPLL is stabilized */ - while( CSCR & CSCR_MPLL_RESTART ); - - imx_set_async_mode(); - } - - local_irq_restore(flags); - - cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); - - pr_debug(KERN_INFO "imx: set frequency %ld Hz, running from %s\n", - freq, mpctl0? "MPLL": "SPLL"); - - return 0; -} - -static int __init imx_cpufreq_driver_init(struct cpufreq_policy *policy) -{ - printk(KERN_INFO "i.MX cpu freq change driver v1.0\n"); - - if (policy->cpu != 0) - return -EINVAL; - - policy->cur = policy->min = policy->max = imx_get_speed(0); - policy->cpuinfo.min_freq = 8000; - policy->cpuinfo.max_freq = 200000; - /* Manual states, that PLL stabilizes in two CLK32 periods */ - policy->cpuinfo.transition_latency = 4 * 1000000000LL / CLK32; - return 0; -} - -static struct cpufreq_driver imx_driver = { - .flags = CPUFREQ_STICKY, - .verify = imx_verify_speed, - .target = imx_set_target, - .get = imx_get_speed, - .init = imx_cpufreq_driver_init, - .name = "imx", -}; - -static int __init imx_cpufreq_init(void) -{ - bclk_div_at_boot = __mfld2val(CSCR_BCLK_DIV, CSCR) + 1; - mpctl0_at_boot = 0; - - system_clk = clk_get(NULL, "system_clk"); - if (IS_ERR(system_clk)) - return PTR_ERR(system_clk); - - mcu_clk = clk_get(NULL, "mcu_clk"); - if (IS_ERR(mcu_clk)) { - clk_put(system_clk); - return PTR_ERR(mcu_clk); - } - - if((CSCR & CSCR_MPEN) && - ((get_cr() & CR_920T_CLOCK_MODE) != CR_920T_FASTBUS_MODE)) - mpctl0_at_boot = MPCTL0; - - return cpufreq_register_driver(&imx_driver); -} - -arch_initcall(imx_cpufreq_init); - |