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-rw-r--r--arch/arm/mach-clps711x/clock.c113
1 files changed, 113 insertions, 0 deletions
diff --git a/arch/arm/mach-clps711x/clock.c b/arch/arm/mach-clps711x/clock.c
new file mode 100644
index 0000000000..5cafba98e9
--- /dev/null
+++ b/arch/arm/mach-clps711x/clock.c
@@ -0,0 +1,113 @@
+/*
+ * Copyright (C) 2012 Alexander Shiyan <shc_work@mail.ru>
+ *
+ * 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 <common.h>
+#include <init.h>
+#include <clock.h>
+#include <asm/io.h>
+#include <linux/clkdev.h>
+
+#include <mach/clps711x.h>
+
+struct clk {
+ unsigned long rate;
+};
+
+static struct clk uart_clk, bus_clk;
+
+uint64_t clocksource_read(void)
+{
+ return ~readw(TC2D);
+}
+
+static struct clocksource cs = {
+ .read = clocksource_read,
+ .mask = CLOCKSOURCE_MASK(16),
+};
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+ return clk->rate;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+int clk_enable(struct clk *clk)
+{
+ /* Do nothing */
+ return 0;
+}
+EXPORT_SYMBOL(clk_enable);
+
+void clk_disable(struct clk *clk)
+{
+ /* Do nothing */
+}
+EXPORT_SYMBOL(clk_disable);
+
+static int clocks_init(void)
+{
+ int osc, ext, pll, cpu, timer;
+ u32 tmp;
+
+ osc = 3686400;
+ ext = 13000000;
+
+ tmp = readl(PLLR) >> 24;
+ if (tmp)
+ pll = (osc * tmp) / 2;
+ else
+ pll = 73728000; /* Default value for old CPUs */
+
+ tmp = readl(SYSFLG2);
+ if (tmp & SYSFLG2_CKMODE) {
+ cpu = ext;
+ bus_clk.rate = cpu;
+ } else {
+ cpu = pll;
+ if (cpu >= 36864000)
+ bus_clk.rate = cpu / 2;
+ else
+ bus_clk.rate = 36864000 / 2;
+ }
+
+ uart_clk.rate = bus_clk.rate / 10;
+
+ if (tmp & SYSFLG2_CKMODE) {
+ tmp = readw(SYSCON2);
+ if (tmp & SYSCON2_OSTB)
+ timer = ext / 26;
+ else
+ timer = 541440;
+ } else
+ timer = cpu / 144;
+
+ tmp = readl(SYSCON1);
+ tmp &= ~SYSCON1_TC2M; /* Free running mode */
+ tmp |= SYSCON1_TC2S; /* High frequency source */
+ writel(tmp, SYSCON1);
+
+ clocks_calc_mult_shift(&cs.mult, &cs.shift, timer, NSEC_PER_SEC, 10);
+
+ return init_clock(&cs);
+}
+core_initcall(clocks_init);
+
+static struct clk_lookup clocks_lookups[] = {
+ CLKDEV_CON_ID("bus", &bus_clk),
+ CLKDEV_DEV_ID("clps711x_serial0", &uart_clk),
+ CLKDEV_DEV_ID("clps711x_serial1", &uart_clk),
+};
+
+static int clkdev_init(void)
+{
+ clkdev_add_table(clocks_lookups, ARRAY_SIZE(clocks_lookups));
+
+ return 0;
+}
+postcore_initcall(clkdev_init);