diff options
Diffstat (limited to 'kernel/arch/arm/plat-samsung/include/plat/cpu-freq.h')
| -rw-r--r-- | kernel/arch/arm/plat-samsung/include/plat/cpu-freq.h | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/kernel/arch/arm/plat-samsung/include/plat/cpu-freq.h b/kernel/arch/arm/plat-samsung/include/plat/cpu-freq.h new file mode 100644 index 000000000..85517ab96 --- /dev/null +++ b/kernel/arch/arm/plat-samsung/include/plat/cpu-freq.h @@ -0,0 +1,145 @@ +/* arch/arm/plat-samsung/include/plat/cpu-freq.h + * + * Copyright (c) 2006-2007 Simtec Electronics + * http://armlinux.simtec.co.uk/ + * Ben Dooks <ben@simtec.co.uk> + * + * S3C CPU frequency scaling support - driver and board + * + * 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/cpufreq.h> + +struct s3c_cpufreq_info; +struct s3c_cpufreq_board; +struct s3c_iotimings; + +/** + * struct s3c_freq - frequency information (mainly for core drivers) + * @fclk: The FCLK frequency in Hz. + * @armclk: The ARMCLK frequency in Hz. + * @hclk_tns: HCLK cycle time in 10ths of nano-seconds. + * @hclk: The HCLK frequency in Hz. + * @pclk: The PCLK frequency in Hz. + * + * This contains the frequency information about the current configuration + * mainly for the core drivers to ensure we do not end up passing about + * a large number of parameters. + * + * The @hclk_tns field is a useful cache for the parts of the drivers that + * need to calculate IO timings and suchlike. + */ +struct s3c_freq { + unsigned long fclk; + unsigned long armclk; + unsigned long hclk_tns; /* in 10ths of ns */ + unsigned long hclk; + unsigned long pclk; +}; + +/** + * struct s3c_cpufreq_freqs - s3c cpufreq notification information. + * @freqs: The cpufreq setting information. + * @old: The old clock settings. + * @new: The new clock settings. + * @pll_changing: Set if the PLL is changing. + * + * Wrapper 'struct cpufreq_freqs' so that any drivers receiving the + * notification can use this information that is not provided by just + * having the core frequency alone. + * + * The pll_changing flag is used to indicate if the PLL itself is + * being set during this change. This is important as the clocks + * will temporarily be set to the XTAL clock during this time, so + * drivers may want to close down their output during this time. + * + * Note, this is not being used by any current drivers and therefore + * may be removed in the future. + */ +struct s3c_cpufreq_freqs { + struct cpufreq_freqs freqs; + struct s3c_freq old; + struct s3c_freq new; + + unsigned int pll_changing:1; +}; + +#define to_s3c_cpufreq(_cf) container_of(_cf, struct s3c_cpufreq_freqs, freqs) + +/** + * struct s3c_clkdivs - clock divisor information + * @p_divisor: Divisor from FCLK to PCLK. + * @h_divisor: Divisor from FCLK to HCLK. + * @arm_divisor: Divisor from FCLK to ARMCLK (not all CPUs). + * @dvs: Non-zero if using DVS mode for ARMCLK. + * + * Divisor settings for the core clocks. + */ +struct s3c_clkdivs { + int p_divisor; + int h_divisor; + int arm_divisor; + unsigned char dvs; +}; + +#define PLLVAL(_m, _p, _s) (((_m) << 12) | ((_p) << 4) | (_s)) + +/** + * struct s3c_pllval - PLL value entry. + * @freq: The frequency for this entry in Hz. + * @pll_reg: The PLL register setting for this PLL value. + */ +struct s3c_pllval { + unsigned long freq; + unsigned long pll_reg; +}; + +/** + * struct s3c_cpufreq_board - per-board cpu frequency informatin + * @refresh: The SDRAM refresh period in nanoseconds. + * @auto_io: Set if the IO timing settings should be generated from the + * initialisation time hardware registers. + * @need_io: Set if the board has external IO on any of the chipselect + * lines that will require the hardware timing registers to be + * updated on a clock change. + * @max: The maxium frequency limits for the system. Any field that + * is left at zero will use the CPU's settings. + * + * This contains the board specific settings that affect how the CPU + * drivers chose settings. These include the memory refresh and IO + * timing information. + * + * Registration depends on the driver being used, the ARMCLK only + * implementation does not currently need this but the older style + * driver requires this to be available. + */ +struct s3c_cpufreq_board { + unsigned int refresh; + unsigned int auto_io:1; /* automatically init io timings. */ + unsigned int need_io:1; /* set if needs io timing support. */ + + /* any non-zero field in here is taken as an upper limit. */ + struct s3c_freq max; /* frequency limits */ +}; + +/* Things depending on frequency scaling. */ +#ifdef CONFIG_ARM_S3C_CPUFREQ +#define __init_or_cpufreq +#else +#define __init_or_cpufreq __init +#endif + +/* Board functions */ + +#ifdef CONFIG_ARM_S3C_CPUFREQ +extern int s3c_cpufreq_setboard(struct s3c_cpufreq_board *board); +#else + +static inline int s3c_cpufreq_setboard(struct s3c_cpufreq_board *board) +{ + return 0; +} +#endif /* CONFIG_ARM_S3C_CPUFREQ */ |