diff options
Diffstat (limited to 'arch/arm/mach-s3c24xx/cpufreq-s3c2440.c')
-rw-r--r-- | arch/arm/mach-s3c24xx/cpufreq-s3c2440.c | 312 |
1 files changed, 0 insertions, 312 deletions
diff --git a/arch/arm/mach-s3c24xx/cpufreq-s3c2440.c b/arch/arm/mach-s3c24xx/cpufreq-s3c2440.c deleted file mode 100644 index 72b2cc8..0000000 --- a/arch/arm/mach-s3c24xx/cpufreq-s3c2440.c +++ /dev/null @@ -1,312 +0,0 @@ -/* - * Copyright (c) 2006-2009 Simtec Electronics - * http://armlinux.simtec.co.uk/ - * Ben Dooks <ben@simtec.co.uk> - * Vincent Sanders <vince@simtec.co.uk> - * - * S3C2440/S3C2442 CPU Frequency scaling - * - * 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. -*/ - -#include <linux/init.h> -#include <linux/module.h> -#include <linux/interrupt.h> -#include <linux/ioport.h> -#include <linux/cpufreq.h> -#include <linux/device.h> -#include <linux/delay.h> -#include <linux/clk.h> -#include <linux/err.h> -#include <linux/io.h> - -#include <mach/hardware.h> - -#include <asm/mach/arch.h> -#include <asm/mach/map.h> - -#include <mach/regs-clock.h> - -#include <plat/cpu.h> -#include <plat/cpu-freq-core.h> -#include <plat/clock.h> - -static struct clk *xtal; -static struct clk *fclk; -static struct clk *hclk; -static struct clk *armclk; - -/* HDIV: 1, 2, 3, 4, 6, 8 */ - -static inline int within_khz(unsigned long a, unsigned long b) -{ - long diff = a - b; - - return (diff >= -1000 && diff <= 1000); -} - -/** - * s3c2440_cpufreq_calcdivs - calculate divider settings - * @cfg: The cpu frequency settings. - * - * Calcualte the divider values for the given frequency settings - * specified in @cfg. The values are stored in @cfg for later use - * by the relevant set routine if the request settings can be reached. - */ -int s3c2440_cpufreq_calcdivs(struct s3c_cpufreq_config *cfg) -{ - unsigned int hdiv, pdiv; - unsigned long hclk, fclk, armclk; - unsigned long hclk_max; - - fclk = cfg->freq.fclk; - armclk = cfg->freq.armclk; - hclk_max = cfg->max.hclk; - - s3c_freq_dbg("%s: fclk is %lu, armclk %lu, max hclk %lu\n", - __func__, fclk, armclk, hclk_max); - - if (armclk > fclk) { - printk(KERN_WARNING "%s: armclk > fclk\n", __func__); - armclk = fclk; - } - - /* if we are in DVS, we need HCLK to be <= ARMCLK */ - if (armclk < fclk && armclk < hclk_max) - hclk_max = armclk; - - for (hdiv = 1; hdiv < 9; hdiv++) { - if (hdiv == 5 || hdiv == 7) - hdiv++; - - hclk = (fclk / hdiv); - if (hclk <= hclk_max || within_khz(hclk, hclk_max)) - break; - } - - s3c_freq_dbg("%s: hclk %lu, div %d\n", __func__, hclk, hdiv); - - if (hdiv > 8) - goto invalid; - - pdiv = (hclk > cfg->max.pclk) ? 2 : 1; - - if ((hclk / pdiv) > cfg->max.pclk) - pdiv++; - - s3c_freq_dbg("%s: pdiv %d\n", __func__, pdiv); - - if (pdiv > 2) - goto invalid; - - pdiv *= hdiv; - - /* calculate a valid armclk */ - - if (armclk < hclk) - armclk = hclk; - - /* if we're running armclk lower than fclk, this really means - * that the system should go into dvs mode, which means that - * armclk is connected to hclk. */ - if (armclk < fclk) { - cfg->divs.dvs = 1; - armclk = hclk; - } else - cfg->divs.dvs = 0; - - cfg->freq.armclk = armclk; - - /* store the result, and then return */ - - cfg->divs.h_divisor = hdiv; - cfg->divs.p_divisor = pdiv; - - return 0; - - invalid: - return -EINVAL; -} - -#define CAMDIVN_HCLK_HALF (S3C2440_CAMDIVN_HCLK3_HALF | \ - S3C2440_CAMDIVN_HCLK4_HALF) - -/** - * s3c2440_cpufreq_setdivs - set the cpu frequency divider settings - * @cfg: The cpu frequency settings. - * - * Set the divisors from the settings in @cfg, which where generated - * during the calculation phase by s3c2440_cpufreq_calcdivs(). - */ -static void s3c2440_cpufreq_setdivs(struct s3c_cpufreq_config *cfg) -{ - unsigned long clkdiv, camdiv; - - s3c_freq_dbg("%s: divsiors: h=%d, p=%d\n", __func__, - cfg->divs.h_divisor, cfg->divs.p_divisor); - - clkdiv = __raw_readl(S3C2410_CLKDIVN); - camdiv = __raw_readl(S3C2440_CAMDIVN); - - clkdiv &= ~(S3C2440_CLKDIVN_HDIVN_MASK | S3C2440_CLKDIVN_PDIVN); - camdiv &= ~CAMDIVN_HCLK_HALF; - - switch (cfg->divs.h_divisor) { - case 1: - clkdiv |= S3C2440_CLKDIVN_HDIVN_1; - break; - - case 2: - clkdiv |= S3C2440_CLKDIVN_HDIVN_2; - break; - - case 6: - camdiv |= S3C2440_CAMDIVN_HCLK3_HALF; - case 3: - clkdiv |= S3C2440_CLKDIVN_HDIVN_3_6; - break; - - case 8: - camdiv |= S3C2440_CAMDIVN_HCLK4_HALF; - case 4: - clkdiv |= S3C2440_CLKDIVN_HDIVN_4_8; - break; - - default: - BUG(); /* we don't expect to get here. */ - } - - if (cfg->divs.p_divisor != cfg->divs.h_divisor) - clkdiv |= S3C2440_CLKDIVN_PDIVN; - - /* todo - set pclk. */ - - /* Write the divisors first with hclk intentionally halved so that - * when we write clkdiv we will under-frequency instead of over. We - * then make a short delay and remove the hclk halving if necessary. - */ - - __raw_writel(camdiv | CAMDIVN_HCLK_HALF, S3C2440_CAMDIVN); - __raw_writel(clkdiv, S3C2410_CLKDIVN); - - ndelay(20); - __raw_writel(camdiv, S3C2440_CAMDIVN); - - clk_set_parent(armclk, cfg->divs.dvs ? hclk : fclk); -} - -static int run_freq_for(unsigned long max_hclk, unsigned long fclk, - int *divs, - struct cpufreq_frequency_table *table, - size_t table_size) -{ - unsigned long freq; - int index = 0; - int div; - - for (div = *divs; div > 0; div = *divs++) { - freq = fclk / div; - - if (freq > max_hclk && div != 1) - continue; - - freq /= 1000; /* table is in kHz */ - index = s3c_cpufreq_addfreq(table, index, table_size, freq); - if (index < 0) - break; - } - - return index; -} - -static int hclk_divs[] = { 1, 2, 3, 4, 6, 8, -1 }; - -static int s3c2440_cpufreq_calctable(struct s3c_cpufreq_config *cfg, - struct cpufreq_frequency_table *table, - size_t table_size) -{ - int ret; - - WARN_ON(cfg->info == NULL); - WARN_ON(cfg->board == NULL); - - ret = run_freq_for(cfg->info->max.hclk, - cfg->info->max.fclk, - hclk_divs, - table, table_size); - - s3c_freq_dbg("%s: returning %d\n", __func__, ret); - - return ret; -} - -struct s3c_cpufreq_info s3c2440_cpufreq_info = { - .max = { - .fclk = 400000000, - .hclk = 133333333, - .pclk = 66666666, - }, - - .locktime_m = 300, - .locktime_u = 300, - .locktime_bits = 16, - - .name = "s3c244x", - .calc_iotiming = s3c2410_iotiming_calc, - .set_iotiming = s3c2410_iotiming_set, - .get_iotiming = s3c2410_iotiming_get, - .set_fvco = s3c2410_set_fvco, - - .set_refresh = s3c2410_cpufreq_setrefresh, - .set_divs = s3c2440_cpufreq_setdivs, - .calc_divs = s3c2440_cpufreq_calcdivs, - .calc_freqtable = s3c2440_cpufreq_calctable, - - .resume_clocks = s3c244x_setup_clocks, - - .debug_io_show = s3c_cpufreq_debugfs_call(s3c2410_iotiming_debugfs), -}; - -static int s3c2440_cpufreq_add(struct device *dev, - struct subsys_interface *sif) -{ - xtal = s3c_cpufreq_clk_get(NULL, "xtal"); - hclk = s3c_cpufreq_clk_get(NULL, "hclk"); - fclk = s3c_cpufreq_clk_get(NULL, "fclk"); - armclk = s3c_cpufreq_clk_get(NULL, "armclk"); - - if (IS_ERR(xtal) || IS_ERR(hclk) || IS_ERR(fclk) || IS_ERR(armclk)) { - printk(KERN_ERR "%s: failed to get clocks\n", __func__); - return -ENOENT; - } - - return s3c_cpufreq_register(&s3c2440_cpufreq_info); -} - -static struct subsys_interface s3c2440_cpufreq_interface = { - .name = "s3c2440_cpufreq", - .subsys = &s3c2440_subsys, - .add_dev = s3c2440_cpufreq_add, -}; - -static int s3c2440_cpufreq_init(void) -{ - return subsys_interface_register(&s3c2440_cpufreq_interface); -} - -/* arch_initcall adds the clocks we need, so use subsys_initcall. */ -subsys_initcall(s3c2440_cpufreq_init); - -static struct subsys_interface s3c2442_cpufreq_interface = { - .name = "s3c2442_cpufreq", - .subsys = &s3c2442_subsys, - .add_dev = s3c2440_cpufreq_add, -}; - -static int s3c2442_cpufreq_init(void) -{ - return subsys_interface_register(&s3c2442_cpufreq_interface); -} -subsys_initcall(s3c2442_cpufreq_init); |