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Diffstat (limited to 'include/linux/soc/samsung/s3c-cpu-freq.h')
-rw-r--r--include/linux/soc/samsung/s3c-cpu-freq.h145
1 files changed, 145 insertions, 0 deletions
diff --git a/include/linux/soc/samsung/s3c-cpu-freq.h b/include/linux/soc/samsung/s3c-cpu-freq.h
new file mode 100644
index 000000000000..63e88fd5dea2
--- /dev/null
+++ b/include/linux/soc/samsung/s3c-cpu-freq.h
@@ -0,0 +1,145 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * 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
+ */
+#ifndef __LINUX_SOC_SAMSUNG_S3C_CPU_FREQ_H
+#define __LINUX_SOC_SAMSUNG_S3C_CPU_FREQ_H
+
+#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 */
+
+#endif