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-rw-r--r--arch/mips/lantiq/clk.c202
1 files changed, 202 insertions, 0 deletions
diff --git a/arch/mips/lantiq/clk.c b/arch/mips/lantiq/clk.c
new file mode 100644
index 000000000..f5fab99d1
--- /dev/null
+++ b/arch/mips/lantiq/clk.c
@@ -0,0 +1,202 @@
+/*
+ * 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.
+ *
+ * Copyright (C) 2010 Thomas Langer <thomas.langer@lantiq.com>
+ * Copyright (C) 2010 John Crispin <john@phrozen.org>
+ */
+#include <linux/io.h>
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/err.h>
+#include <linux/list.h>
+
+#include <asm/time.h>
+#include <asm/irq.h>
+#include <asm/div64.h>
+
+#include <lantiq_soc.h>
+
+#include "clk.h"
+#include "prom.h"
+
+/* lantiq socs have 3 static clocks */
+static struct clk cpu_clk_generic[4];
+
+void clkdev_add_static(unsigned long cpu, unsigned long fpi,
+ unsigned long io, unsigned long ppe)
+{
+ cpu_clk_generic[0].rate = cpu;
+ cpu_clk_generic[1].rate = fpi;
+ cpu_clk_generic[2].rate = io;
+ cpu_clk_generic[3].rate = ppe;
+}
+
+struct clk *clk_get_cpu(void)
+{
+ return &cpu_clk_generic[0];
+}
+
+struct clk *clk_get_fpi(void)
+{
+ return &cpu_clk_generic[1];
+}
+EXPORT_SYMBOL_GPL(clk_get_fpi);
+
+struct clk *clk_get_io(void)
+{
+ return &cpu_clk_generic[2];
+}
+
+struct clk *clk_get_ppe(void)
+{
+ return &cpu_clk_generic[3];
+}
+EXPORT_SYMBOL_GPL(clk_get_ppe);
+
+static inline int clk_good(struct clk *clk)
+{
+ return clk && !IS_ERR(clk);
+}
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+ if (unlikely(!clk_good(clk)))
+ return 0;
+
+ if (clk->rate != 0)
+ return clk->rate;
+
+ if (clk->get_rate != NULL)
+ return clk->get_rate();
+
+ return 0;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+int clk_set_rate(struct clk *clk, unsigned long rate)
+{
+ if (unlikely(!clk_good(clk)))
+ return 0;
+ if (clk->rates && *clk->rates) {
+ unsigned long *r = clk->rates;
+
+ while (*r && (*r != rate))
+ r++;
+ if (!*r) {
+ pr_err("clk %s.%s: trying to set invalid rate %ld\n",
+ clk->cl.dev_id, clk->cl.con_id, rate);
+ return -1;
+ }
+ }
+ clk->rate = rate;
+ return 0;
+}
+EXPORT_SYMBOL(clk_set_rate);
+
+long clk_round_rate(struct clk *clk, unsigned long rate)
+{
+ if (unlikely(!clk_good(clk)))
+ return 0;
+ if (clk->rates && *clk->rates) {
+ unsigned long *r = clk->rates;
+
+ while (*r && (*r != rate))
+ r++;
+ if (!*r) {
+ return clk->rate;
+ }
+ }
+ return rate;
+}
+EXPORT_SYMBOL(clk_round_rate);
+
+int clk_enable(struct clk *clk)
+{
+ if (unlikely(!clk_good(clk)))
+ return -1;
+
+ if (clk->enable)
+ return clk->enable(clk);
+
+ return -1;
+}
+EXPORT_SYMBOL(clk_enable);
+
+void clk_disable(struct clk *clk)
+{
+ if (unlikely(!clk_good(clk)))
+ return;
+
+ if (clk->disable)
+ clk->disable(clk);
+}
+EXPORT_SYMBOL(clk_disable);
+
+int clk_activate(struct clk *clk)
+{
+ if (unlikely(!clk_good(clk)))
+ return -1;
+
+ if (clk->activate)
+ return clk->activate(clk);
+
+ return -1;
+}
+EXPORT_SYMBOL(clk_activate);
+
+void clk_deactivate(struct clk *clk)
+{
+ if (unlikely(!clk_good(clk)))
+ return;
+
+ if (clk->deactivate)
+ clk->deactivate(clk);
+}
+EXPORT_SYMBOL(clk_deactivate);
+
+struct clk *clk_get_parent(struct clk *clk)
+{
+ return NULL;
+}
+EXPORT_SYMBOL(clk_get_parent);
+
+int clk_set_parent(struct clk *clk, struct clk *parent)
+{
+ return 0;
+}
+EXPORT_SYMBOL(clk_set_parent);
+
+static inline u32 get_counter_resolution(void)
+{
+ u32 res;
+
+ __asm__ __volatile__(
+ ".set push\n"
+ ".set mips32r2\n"
+ "rdhwr %0, $3\n"
+ ".set pop\n"
+ : "=&r" (res)
+ : /* no input */
+ : "memory");
+
+ return res;
+}
+
+void __init plat_time_init(void)
+{
+ struct clk *clk;
+
+ ltq_soc_init();
+
+ clk = clk_get_cpu();
+ mips_hpt_frequency = clk_get_rate(clk) / get_counter_resolution();
+ write_c0_compare(read_c0_count());
+ pr_info("CPU Clock: %ldMHz\n", clk_get_rate(clk) / 1000000);
+ clk_put(clk);
+}