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authorKelvin Cheung <keguang.zhang@gmail.com>2012-08-20 18:05:35 +0800
committerMike Turquette <mturquette@linaro.org>2012-08-31 11:05:18 -0700
commit5175cb5894d606f1756c07a685e6dcabd2d8745a (patch)
tree2f0ffc6675b5c7c7324b6bf1980cd8c98bfb7768 /drivers/clk/clk-ls1x.c
parente5ad7ac73cdd43c48998f1f43261c6209aebe00b (diff)
clk: add Loongson1B clock support
This adds clock support to Loongson1B SoC using the common clock infrastructure. Signed-off-by: Kelvin Cheung <keguang.zhang@gmail.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
Diffstat (limited to 'drivers/clk/clk-ls1x.c')
-rw-r--r--drivers/clk/clk-ls1x.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/drivers/clk/clk-ls1x.c b/drivers/clk/clk-ls1x.c
new file mode 100644
index 00000000000..f20b750235f
--- /dev/null
+++ b/drivers/clk/clk-ls1x.c
@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2012 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/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+
+#include <loongson1.h>
+
+#define OSC 33
+
+static DEFINE_SPINLOCK(_lock);
+
+static int ls1x_pll_clk_enable(struct clk_hw *hw)
+{
+ return 0;
+}
+
+static void ls1x_pll_clk_disable(struct clk_hw *hw)
+{
+}
+
+static unsigned long ls1x_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ u32 pll, rate;
+
+ pll = __raw_readl(LS1X_CLK_PLL_FREQ);
+ rate = ((12 + (pll & 0x3f)) * 1000000) +
+ ((((pll >> 8) & 0x3ff) * 1000000) >> 10);
+ rate *= OSC;
+ rate >>= 1;
+
+ return rate;
+}
+
+static const struct clk_ops ls1x_pll_clk_ops = {
+ .enable = ls1x_pll_clk_enable,
+ .disable = ls1x_pll_clk_disable,
+ .recalc_rate = ls1x_pll_recalc_rate,
+};
+
+static struct clk * __init clk_register_pll(struct device *dev,
+ const char *name, const char *parent_name, unsigned long flags)
+{
+ struct clk_hw *hw;
+ struct clk *clk;
+ struct clk_init_data init;
+
+ /* allocate the divider */
+ hw = kzalloc(sizeof(struct clk_hw), GFP_KERNEL);
+ if (!hw) {
+ pr_err("%s: could not allocate clk_hw\n", __func__);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ init.name = name;
+ init.ops = &ls1x_pll_clk_ops;
+ init.flags = flags | CLK_IS_BASIC;
+ init.parent_names = (parent_name ? &parent_name : NULL);
+ init.num_parents = (parent_name ? 1 : 0);
+ hw->init = &init;
+
+ /* register the clock */
+ clk = clk_register(dev, hw);
+
+ if (IS_ERR(clk))
+ kfree(hw);
+
+ return clk;
+}
+
+void __init ls1x_clk_init(void)
+{
+ struct clk *clk;
+
+ clk = clk_register_pll(NULL, "pll_clk", NULL, CLK_IS_ROOT);
+ clk_prepare_enable(clk);
+
+ clk = clk_register_divider(NULL, "cpu_clk", "pll_clk",
+ CLK_SET_RATE_PARENT, LS1X_CLK_PLL_DIV, DIV_CPU_SHIFT,
+ DIV_CPU_WIDTH, CLK_DIVIDER_ONE_BASED, &_lock);
+ clk_prepare_enable(clk);
+ clk_register_clkdev(clk, "cpu", NULL);
+
+ clk = clk_register_divider(NULL, "dc_clk", "pll_clk",
+ CLK_SET_RATE_PARENT, LS1X_CLK_PLL_DIV, DIV_DC_SHIFT,
+ DIV_DC_WIDTH, CLK_DIVIDER_ONE_BASED, &_lock);
+ clk_prepare_enable(clk);
+ clk_register_clkdev(clk, "dc", NULL);
+
+ clk = clk_register_divider(NULL, "ahb_clk", "pll_clk",
+ CLK_SET_RATE_PARENT, LS1X_CLK_PLL_DIV, DIV_DDR_SHIFT,
+ DIV_DDR_WIDTH, CLK_DIVIDER_ONE_BASED, &_lock);
+ clk_prepare_enable(clk);
+ clk_register_clkdev(clk, "ahb", NULL);
+ clk_register_clkdev(clk, "stmmaceth", NULL);
+
+ clk = clk_register_fixed_factor(NULL, "apb_clk", "ahb_clk", 0, 1, 2);
+ clk_prepare_enable(clk);
+ clk_register_clkdev(clk, "apb", NULL);
+ clk_register_clkdev(clk, "serial8250", NULL);
+}