diff options
| -rw-r--r-- | arch/arm/plat-s3c/include/plat/cpu-freq.h | 91 |
1 files changed, 81 insertions, 10 deletions
diff --git a/arch/arm/plat-s3c/include/plat/cpu-freq.h b/arch/arm/plat-s3c/include/plat/cpu-freq.h index c86a13307e9..0ba7670fd07 100644 --- a/arch/arm/plat-s3c/include/plat/cpu-freq.h +++ b/arch/arm/plat-s3c/include/plat/cpu-freq.h @@ -17,6 +17,21 @@ 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; @@ -25,33 +40,75 @@ struct s3c_freq { unsigned long pclk; }; -/* wrapper 'struct cpufreq_freqs' so that any drivers receiving the +/** + * 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; /* fclk / pclk */ - int h_divisor; /* fclk / hclk */ - int arm_divisor; /* not all cpus have this. */ - unsigned char dvs; /* using dvs mode to arm. */ + 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_config - current cpu frequency configuration + * @freq: The current settings for the core clocks. + * @pll: The PLL table entry for the current PLL settings. + * @divs: The divisor settings for the core clocks. + * @info: The current core driver information. + * @board: The information for the board we are running on. + * + * This is for the core drivers that need to know information about + * the current settings and values. It should not be needed by any + * device drivers. +*/ struct s3c_cpufreq_config { struct s3c_freq freq; struct s3c_pllval pll; @@ -60,13 +117,27 @@ struct s3c_cpufreq_config { struct s3c_cpufreq_board *board; }; -/* s3c_cpufreq_board +/** + * 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. * - * per-board configuraton information, such as memory refresh and - * how to initialise IO timings. + * 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; /* refresh period in ns */ + unsigned int refresh; unsigned int auto_io:1; /* automatically init io timings. */ unsigned int need_io:1; /* set if needs io timing support. */ |