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author | Russell King <rmk@dyn-67.arm.linux.org.uk> | 2009-09-12 12:02:26 +0100 |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2009-09-12 12:02:26 +0100 |
commit | ddd559b13f6d2fe3ad68c4b3f5235fd3c2eae4e3 (patch) | |
tree | d827bca3fc825a0ac33efbcd493713be40fcc812 /arch/arm/plat-s3c24xx/s3c2410-cpufreq-utils.c | |
parent | cf7a2b4fb6a9b86779930a0a123b0df41aa9208f (diff) | |
parent | f17a1f06d2fa93f4825be572622eb02c4894db4e (diff) | |
download | blackbird-op-linux-ddd559b13f6d2fe3ad68c4b3f5235fd3c2eae4e3.tar.gz blackbird-op-linux-ddd559b13f6d2fe3ad68c4b3f5235fd3c2eae4e3.zip |
Merge branch 'devel-stable' into devel
Conflicts:
MAINTAINERS
arch/arm/mm/fault.c
Diffstat (limited to 'arch/arm/plat-s3c24xx/s3c2410-cpufreq-utils.c')
-rw-r--r-- | arch/arm/plat-s3c24xx/s3c2410-cpufreq-utils.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/arch/arm/plat-s3c24xx/s3c2410-cpufreq-utils.c b/arch/arm/plat-s3c24xx/s3c2410-cpufreq-utils.c new file mode 100644 index 000000000000..43ea80190d87 --- /dev/null +++ b/arch/arm/plat-s3c24xx/s3c2410-cpufreq-utils.c @@ -0,0 +1,64 @@ +/* linux/arch/arm/plat-s3c24xx/s3c2410-cpufreq-utils.c + * + * Copyright (c) 2009 Simtec Electronics + * http://armlinux.simtec.co.uk/ + * Ben Dooks <ben@simtec.co.uk> + * + * S3C24XX CPU Frequency scaling - utils for S3C2410/S3C2440/S3C2442 + * + * 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/kernel.h> +#include <linux/errno.h> +#include <linux/cpufreq.h> +#include <linux/io.h> + +#include <mach/map.h> +#include <mach/regs-mem.h> +#include <mach/regs-clock.h> + +#include <plat/cpu-freq-core.h> + +/** + * s3c2410_cpufreq_setrefresh - set SDRAM refresh value + * @cfg: The frequency configuration + * + * Set the SDRAM refresh value appropriately for the configured + * frequency. + */ +void s3c2410_cpufreq_setrefresh(struct s3c_cpufreq_config *cfg) +{ + struct s3c_cpufreq_board *board = cfg->board; + unsigned long refresh; + unsigned long refval; + + /* Reduce both the refresh time (in ns) and the frequency (in MHz) + * down to ensure that we do not overflow 32 bit numbers. + * + * This should work for HCLK up to 133MHz and refresh period up + * to 30usec. + */ + + refresh = (cfg->freq.hclk / 100) * (board->refresh / 10); + refresh = DIV_ROUND_UP(refresh, (1000 * 1000)); /* apply scale */ + refresh = (1 << 11) + 1 - refresh; + + s3c_freq_dbg("%s: refresh value %lu\n", __func__, refresh); + + refval = __raw_readl(S3C2410_REFRESH); + refval &= ~((1 << 12) - 1); + refval |= refresh; + __raw_writel(refval, S3C2410_REFRESH); +} + +/** + * s3c2410_set_fvco - set the PLL value + * @cfg: The frequency configuration + */ +void s3c2410_set_fvco(struct s3c_cpufreq_config *cfg) +{ + __raw_writel(cfg->pll.index, S3C2410_MPLLCON); +} |