aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/mach-imx/cpufreq.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mach-imx/cpufreq.c')
-rw-r--r--arch/arm/mach-imx/cpufreq.c315
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);
-