--- /dev/null
+/* linux/arch/arm/plat-samsung/clock-clksrc.c
+ *
+ * Copyright 2008 Simtec Electronics
+ * Ben Dooks <ben@simtec.co.uk>
+ * http://armlinux.simtec.co.uk/
+ *
+ * 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/kernel.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/sysdev.h>
+#include <linux/io.h>
+
+#include <plat/clock.h>
+#include <plat/clock-clksrc.h>
+#include <plat/cpu-freq.h>
+
+static inline struct clksrc_clk *to_clksrc(struct clk *clk)
+{
+ return container_of(clk, struct clksrc_clk, clk);
+}
+
+static inline u32 bit_mask(u32 shift, u32 nr_bits)
+{
+ u32 mask = 0xffffffff >> (32 - nr_bits);
+
+ return mask << shift;
+}
+
+static unsigned long s3c_getrate_clksrc(struct clk *clk)
+{
+ struct clksrc_clk *sclk = to_clksrc(clk);
+ unsigned long rate = clk_get_rate(clk->parent);
+ u32 clkdiv = __raw_readl(sclk->reg_div.reg);
+ u32 mask = bit_mask(sclk->reg_div.shift, sclk->reg_div.size);
+
+ clkdiv &= mask;
+ clkdiv >>= sclk->reg_div.shift;
+ clkdiv++;
+
+ rate /= clkdiv;
+ return rate;
+}
+
+static int s3c_setrate_clksrc(struct clk *clk, unsigned long rate)
+{
+ struct clksrc_clk *sclk = to_clksrc(clk);
+ void __iomem *reg = sclk->reg_div.reg;
+ unsigned int div;
+ u32 mask = bit_mask(sclk->reg_div.shift, sclk->reg_div.size);
+ u32 val;
+
+ rate = clk_round_rate(clk, rate);
+ div = clk_get_rate(clk->parent) / rate;
+ if (div > 16)
+ return -EINVAL;
+
+ val = __raw_readl(reg);
+ val &= ~mask;
+ val |= (div - 1) << sclk->reg_div.shift;
+ __raw_writel(val, reg);
+
+ return 0;
+}
+
+static int s3c_setparent_clksrc(struct clk *clk, struct clk *parent)
+{
+ struct clksrc_clk *sclk = to_clksrc(clk);
+ struct clksrc_sources *srcs = sclk->sources;
+ u32 clksrc = __raw_readl(sclk->reg_src.reg);
+ u32 mask = bit_mask(sclk->reg_src.shift, sclk->reg_src.size);
+ int src_nr = -1;
+ int ptr;
+
+ for (ptr = 0; ptr < srcs->nr_sources; ptr++)
+ if (srcs->sources[ptr] == parent) {
+ src_nr = ptr;
+ break;
+ }
+
+ if (src_nr >= 0 && sclk->reg_src.reg) {
+ clk->parent = parent;
+
+ clksrc &= ~mask;
+ clksrc |= src_nr << sclk->reg_src.shift;
+
+ __raw_writel(clksrc, sclk->reg_src.reg);
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static unsigned long s3c_roundrate_clksrc(struct clk *clk,
+ unsigned long rate)
+{
+ unsigned long parent_rate = clk_get_rate(clk->parent);
+ int div;
+
+ if (rate >= parent_rate)
+ rate = parent_rate;
+ else {
+ div = parent_rate / rate;
+ if (parent_rate % rate)
+ div++;
+
+ if (div == 0)
+ div = 1;
+ if (div > 16)
+ div = 16;
+
+ rate = parent_rate / div;
+ }
+
+ return rate;
+}
+
+/* Clock initialisation code */
+
+void __init_or_cpufreq s3c_set_clksrc(struct clksrc_clk *clk)
+{
+ struct clksrc_sources *srcs = clk->sources;
+ u32 mask = bit_mask(clk->reg_src.shift, clk->reg_src.size);
+ u32 clksrc = 0;
+
+ if (clk->reg_src.reg)
+ clksrc = __raw_readl(clk->reg_src.reg);
+
+ clksrc &= mask;
+ clksrc >>= clk->reg_src.shift;
+
+ if (clksrc > srcs->nr_sources || !srcs->sources[clksrc]) {
+ printk(KERN_ERR "%s: bad source %d\n",
+ clk->clk.name, clksrc);
+ return;
+ }
+
+ clk->clk.parent = srcs->sources[clksrc];
+
+ printk(KERN_INFO "%s: source is %s (%d), rate is %ld\n",
+ clk->clk.name, clk->clk.parent->name, clksrc,
+ clk_get_rate(&clk->clk));
+}
+
+void __init s3c_register_clksrc(struct clksrc_clk *clksrc, int size)
+{
+ int ret;
+
+ for (; size > 0; size--, clksrc++) {
+ /* fill in the default functions */
+ if (!clksrc->clk.set_parent)
+ clksrc->clk.set_parent = s3c_setparent_clksrc;
+ if (!clksrc->clk.get_rate)
+ clksrc->clk.get_rate = s3c_getrate_clksrc;
+ if (!clksrc->clk.set_rate)
+ clksrc->clk.set_rate = s3c_setrate_clksrc;
+ if (!clksrc->clk.round_rate)
+ clksrc->clk.round_rate = s3c_roundrate_clksrc;
+
+ s3c_set_clksrc(clksrc);
+
+ ret = s3c24xx_register_clock(&clksrc->clk);
+
+ if (ret < 0) {
+ printk(KERN_ERR "%s: failed to register %s (%d)\n",
+ __func__, clksrc->clk.name, ret);
+ }
+ }
+}
--- /dev/null
+/* linux/arch/arm/plat-samsung/include/plat/clock-clksrc.h
+ *
+ * Parts taken from arch/arm/plat-s3c64xx/clock.c
+ * Copyright 2008 Openmoko, Inc.
+ * Copyright 2008 Simtec Electronics
+ * Ben Dooks <ben@simtec.co.uk>
+ * http://armlinux.simtec.co.uk/
+ *
+ * Copyright 2009 Ben Dooks <ben-linux@fluff.org>
+ * Copyright 2009 Harald Welte
+ *
+ * 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.
+*/
+
+/**
+ * struct clksrc_sources - list of sources for a given clock
+ * @sources: array of pointers to clocks
+ * @nr_sources: The size of @sources
+ */
+struct clksrc_sources {
+ unsigned int nr_sources;
+ struct clk **sources;
+};
+
+/**
+ * struct clksrc_reg - register definition for clock control bits
+ * @reg: pointer to the register in virtual memory.
+ * @shift: the shift in bits to where the bitfield is.
+ * @size: the size in bits of the bitfield.
+ *
+ * This specifies the size and position of the bits we are interested
+ * in within the register specified by @reg.
+ */
+struct clksrc_reg {
+ void __iomem *reg;
+ unsigned short shift;
+ unsigned short size;
+};
+
+/**
+ * struct clksrc_clk - class of clock for newer style samsung devices.
+ * @clk: the standard clock representation
+ * @sources: the sources for this clock
+ * @reg_src: the register definition for selecting the clock's source
+ * @reg_div: the register definition for the clock's output divisor
+ *
+ * This clock implements the features required by the newer SoCs where
+ * the standard clock block provides an input mux and a post-mux divisor
+ * to provide the periperhal's clock.
+ *
+ * The array of @sources provides the mapping of mux position to the
+ * clock, and @reg_src shows the code where to modify to change the mux
+ * position. The @reg_div defines how to change the divider settings on
+ * the output.
+ */
+struct clksrc_clk {
+ struct clk clk;
+ struct clksrc_sources *sources;
+
+ struct clksrc_reg reg_src;
+ struct clksrc_reg reg_div;
+};
+
+extern void s3c_set_clksrc(struct clksrc_clk *clk);
+
+/**
+ * s3c_register_clksrc() register clocks from an array of clksrc clocks
+ * @srcs: The array of clocks to register
+ * @size: The size of the @srcs array.
+ *
+ * Initialise and register the array of clocks described by @srcs.
+ */
+extern void s3c_register_clksrc(struct clksrc_clk *srcs, int size);
projects / ~shefty / rdma-dev.git / commitdiff