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-rw-r--r--arch/mips/loongson1/common/clock.c165
1 files changed, 165 insertions, 0 deletions
diff --git a/arch/mips/loongson1/common/clock.c b/arch/mips/loongson1/common/clock.c
new file mode 100644
index 000000000000..2d98fb030596
--- /dev/null
+++ b/arch/mips/loongson1/common/clock.c
@@ -0,0 +1,165 @@
+/*
+ * Copyright (c) 2011 Zhang, Keguang <keguang.zhang@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <asm/clock.h>
+#include <asm/time.h>
+
+#include <loongson1.h>
+
+static LIST_HEAD(clocks);
+static DEFINE_MUTEX(clocks_mutex);
+
+struct clk *clk_get(struct device *dev, const char *name)
+{
+ struct clk *c;
+ struct clk *ret = NULL;
+
+ mutex_lock(&clocks_mutex);
+ list_for_each_entry(c, &clocks, node) {
+ if (!strcmp(c->name, name)) {
+ ret = c;
+ break;
+ }
+ }
+ mutex_unlock(&clocks_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL(clk_get);
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+ return clk->rate;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+static void pll_clk_init(struct clk *clk)
+{
+ u32 pll;
+
+ pll = __raw_readl(LS1X_CLK_PLL_FREQ);
+ clk->rate = (12 + (pll & 0x3f)) * 33 / 2
+ + ((pll >> 8) & 0x3ff) * 33 / 1024 / 2;
+ clk->rate *= 1000000;
+}
+
+static void cpu_clk_init(struct clk *clk)
+{
+ u32 pll, ctrl;
+
+ pll = clk_get_rate(clk->parent);
+ ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_CPU;
+ clk->rate = pll / (ctrl >> DIV_CPU_SHIFT);
+}
+
+static void ddr_clk_init(struct clk *clk)
+{
+ u32 pll, ctrl;
+
+ pll = clk_get_rate(clk->parent);
+ ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_DDR;
+ clk->rate = pll / (ctrl >> DIV_DDR_SHIFT);
+}
+
+static void dc_clk_init(struct clk *clk)
+{
+ u32 pll, ctrl;
+
+ pll = clk_get_rate(clk->parent);
+ ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_DC;
+ clk->rate = pll / (ctrl >> DIV_DC_SHIFT);
+}
+
+static struct clk_ops pll_clk_ops = {
+ .init = pll_clk_init,
+};
+
+static struct clk_ops cpu_clk_ops = {
+ .init = cpu_clk_init,
+};
+
+static struct clk_ops ddr_clk_ops = {
+ .init = ddr_clk_init,
+};
+
+static struct clk_ops dc_clk_ops = {
+ .init = dc_clk_init,
+};
+
+static struct clk pll_clk = {
+ .name = "pll",
+ .ops = &pll_clk_ops,
+};
+
+static struct clk cpu_clk = {
+ .name = "cpu",
+ .parent = &pll_clk,
+ .ops = &cpu_clk_ops,
+};
+
+static struct clk ddr_clk = {
+ .name = "ddr",
+ .parent = &pll_clk,
+ .ops = &ddr_clk_ops,
+};
+
+static struct clk dc_clk = {
+ .name = "dc",
+ .parent = &pll_clk,
+ .ops = &dc_clk_ops,
+};
+
+int clk_register(struct clk *clk)
+{
+ mutex_lock(&clocks_mutex);
+ list_add(&clk->node, &clocks);
+ if (clk->ops->init)
+ clk->ops->init(clk);
+ mutex_unlock(&clocks_mutex);
+
+ return 0;
+}
+EXPORT_SYMBOL(clk_register);
+
+static struct clk *ls1x_clks[] = {
+ &pll_clk,
+ &cpu_clk,
+ &ddr_clk,
+ &dc_clk,
+};
+
+int __init ls1x_clock_init(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ls1x_clks); i++)
+ clk_register(ls1x_clks[i]);
+
+ return 0;
+}
+
+void __init plat_time_init(void)
+{
+ struct clk *clk;
+
+ /* Initialize LS1X clocks */
+ ls1x_clock_init();
+
+ /* setup mips r4k timer */
+ clk = clk_get(NULL, "cpu");
+ if (IS_ERR(clk))
+ panic("unable to get dc clock, err=%ld", PTR_ERR(clk));
+
+ mips_hpt_frequency = clk_get_rate(clk) / 2;
+}