Initial import

1 files changed, 162 insertions, 0 deletions

diff --git a/drivers/clk/clk-ls1x.c b/drivers/clk/clk-ls1x.c
new file mode 100644
index 000000000..ca80103ac
--- /dev/null
+++ b/drivers/clk/clk-ls1x.c
@@ -0,0 +1,162 @@
+/*
+ * 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 * 1000000)
+#define DIV_APB		2
+
+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) + (((pll >> 8) & 0x3ff) >> 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;
+}
+
+static const char const *cpu_parents[] = { "cpu_clk_div", "osc_33m_clk", };
+static const char const *ahb_parents[] = { "ahb_clk_div", "osc_33m_clk", };
+static const char const *dc_parents[] = { "dc_clk_div", "osc_33m_clk", };
+
+void __init ls1x_clk_init(void)
+{
+	struct clk *clk;
+
+	clk = clk_register_fixed_rate(NULL, "osc_33m_clk", NULL, CLK_IS_ROOT,
+				      OSC);
+	clk_register_clkdev(clk, "osc_33m_clk", NULL);
+
+	/* clock derived from 33 MHz OSC clk */
+	clk = clk_register_pll(NULL, "pll_clk", "osc_33m_clk", 0);
+	clk_register_clkdev(clk, "pll_clk", NULL);
+
+	/* clock derived from PLL clk */
+	/*                                 _____
+	 *         _______________________|     |
+	 * OSC ___/                       | MUX |___ CPU CLK
+	 *        \___ PLL ___ CPU DIV ___|     |
+	 *                                |_____|
+	 */
+	clk = clk_register_divider(NULL, "cpu_clk_div", "pll_clk",
+				   CLK_GET_RATE_NOCACHE, LS1X_CLK_PLL_DIV,
+				   DIV_CPU_SHIFT, DIV_CPU_WIDTH,
+				   CLK_DIVIDER_ONE_BASED |
+				   CLK_DIVIDER_ROUND_CLOSEST, &_lock);
+	clk_register_clkdev(clk, "cpu_clk_div", NULL);
+	clk = clk_register_mux(NULL, "cpu_clk", cpu_parents,
+			       ARRAY_SIZE(cpu_parents),
+			       CLK_SET_RATE_NO_REPARENT, LS1X_CLK_PLL_DIV,
+			       BYPASS_CPU_SHIFT, BYPASS_CPU_WIDTH, 0, &_lock);
+	clk_register_clkdev(clk, "cpu_clk", NULL);
+
+	/*                                 _____
+	 *         _______________________|     |
+	 * OSC ___/                       | MUX |___ DC  CLK
+	 *        \___ PLL ___ DC  DIV ___|     |
+	 *                                |_____|
+	 */
+	clk = clk_register_divider(NULL, "dc_clk_div", "pll_clk",
+				   0, LS1X_CLK_PLL_DIV, DIV_DC_SHIFT,
+				   DIV_DC_WIDTH, CLK_DIVIDER_ONE_BASED, &_lock);
+	clk_register_clkdev(clk, "dc_clk_div", NULL);
+	clk = clk_register_mux(NULL, "dc_clk", dc_parents,
+			       ARRAY_SIZE(dc_parents),
+			       CLK_SET_RATE_NO_REPARENT, LS1X_CLK_PLL_DIV,
+			       BYPASS_DC_SHIFT, BYPASS_DC_WIDTH, 0, &_lock);
+	clk_register_clkdev(clk, "dc_clk", NULL);
+
+	/*                                 _____
+	 *         _______________________|     |
+	 * OSC ___/                       | MUX |___ DDR CLK
+	 *        \___ PLL ___ DDR DIV ___|     |
+	 *                                |_____|
+	 */
+	clk = clk_register_divider(NULL, "ahb_clk_div", "pll_clk",
+				   0, LS1X_CLK_PLL_DIV, DIV_DDR_SHIFT,
+				   DIV_DDR_WIDTH, CLK_DIVIDER_ONE_BASED,
+				   &_lock);
+	clk_register_clkdev(clk, "ahb_clk_div", NULL);
+	clk = clk_register_mux(NULL, "ahb_clk", ahb_parents,
+			       ARRAY_SIZE(ahb_parents),
+			       CLK_SET_RATE_NO_REPARENT, LS1X_CLK_PLL_DIV,
+			       BYPASS_DDR_SHIFT, BYPASS_DDR_WIDTH, 0, &_lock);
+	clk_register_clkdev(clk, "ahb_clk", NULL);
+	clk_register_clkdev(clk, "stmmaceth", NULL);
+
+	/* clock derived from AHB clk */
+	/* APB clk is always half of the AHB clk */
+	clk = clk_register_fixed_factor(NULL, "apb_clk", "ahb_clk", 0, 1,
+					DIV_APB);
+	clk_register_clkdev(clk, "apb_clk", NULL);
+	clk_register_clkdev(clk, "ls1x_i2c", NULL);
+	clk_register_clkdev(clk, "ls1x_pwmtimer", NULL);
+	clk_register_clkdev(clk, "ls1x_spi", NULL);
+	clk_register_clkdev(clk, "ls1x_wdt", NULL);
+	clk_register_clkdev(clk, "serial8250", NULL);
+}