1 files changed, 271 insertions, 0 deletions
diff --git a/target/linux/mcs814x/files-3.3/arch/arm/mach-mcs814x/clock.c b/target/linux/mcs814x/files-3.3/arch/arm/mach-mcs814x/clock.c
new file mode 100644
index 000000000..413bfecaa
--- /dev/null
+++ b/target/linux/mcs814x/files-3.3/arch/arm/mach-mcs814x/clock.c
@@ -0,0 +1,271 @@
+/*
+ * Moschip MCS814x clock routines
+ *
+ * Copyright (C) 2012, Florian Fainelli <florian@openwrt.org>
+ *
+ * Licensed under GPLv2
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/export.h>
+#include <linux/spinlock.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/clkdev.h>
+#include <linux/clk.h>
+
+#include <mach/mcs814x.h>
+
+#include "common.h"
+
+#define KHZ	1000
+#define MHZ	(KHZ * KHZ)
+
+struct clk_ops {
+	unsigned long (*get_rate)(struct clk *clk);
+	int (*set_rate)(struct clk *clk, unsigned long rate);
+	struct clk *(*get_parent)(struct clk *clk);
+	int (*enable)(struct clk *clk, int enable);
+};
+
+struct clk {
+	struct clk *parent;     	/* parent clk */
+	unsigned long rate;     	/* clock rate in Hz */
+	unsigned long divider;		/* clock divider */
+	u32 usecount;			/* reference count */
+	struct clk_ops *ops;		/* clock operation */
+	u32 enable_reg;			/* clock enable register */
+	u32 enable_mask;		/* clock enable mask */
+};
+
+static unsigned long clk_divide_parent(struct clk *clk)
+{
+	if (clk->parent && clk->divider)
+		return clk_get_rate(clk->parent) / clk->divider;
+	else
+		return 0;
+}
+
+static int clk_local_onoff_enable(struct clk *clk, int enable)
+{
+	u32 tmp;
+
+	/* no enable_reg means the clock is always enabled */
+	if (!clk->enable_reg)
+		return 0;
+
+	tmp = readl_relaxed(mcs814x_sysdbg_base + clk->enable_reg);
+	if (!enable)
+		tmp &= ~clk->enable_mask;
+	else
+		tmp |= clk->enable_mask;
+
+	writel_relaxed(tmp, mcs814x_sysdbg_base + clk->enable_reg);
+
+	return 0;
+}
+
+static struct clk_ops default_clk_ops = {
+	.get_rate	= clk_divide_parent,
+	.enable		= clk_local_onoff_enable,
+};
+
+static DEFINE_SPINLOCK(clocks_lock);
+
+static const unsigned long cpu_freq_table[] = {
+	175000,
+	300000,
+	125000,
+	137500,
+	212500,
+	250000,
+	162500,
+	187500,
+	162500,
+	150000,
+	225000,
+	237500,
+	200000,
+	262500,
+	275000,
+	287500
+};
+
+static struct clk clk_cpu;
+
+/* System clock is fixed at 50Mhz */
+static struct clk clk_sys = {
+	.rate	= 50 * MHZ,
+};
+
+static struct clk clk_sdram;
+
+static struct clk clk_timer0 = {
+	.parent	= &clk_sdram,
+	.divider = 2,
+	.ops	= &default_clk_ops,
+};
+
+static struct clk clk_timer1_2 = {
+	.parent	= &clk_sys,
+};
+
+/* Watchdog clock is system clock / 128 */
+static struct clk clk_wdt = {
+	.parent	= &clk_sys,
+	.divider = 128,
+	.ops	= &default_clk_ops,
+};
+
+static struct clk clk_emac = {
+	.ops		= &default_clk_ops,
+	.enable_reg	= SYSDBG_SYSCTL,
+	.enable_mask	= SYSCTL_EMAC,
+};
+
+static struct clk clk_ephy = {
+	.ops		= &default_clk_ops,
+	.enable_reg	= SYSDBG_PLL_CTL,
+	.enable_mask	= ~SYSCTL_EPHY,	/* active low */
+};
+
+static struct clk clk_cipher = {
+	.ops		= &default_clk_ops,
+	.enable_reg	= SYSDBG_SYSCTL,
+	.enable_mask	= SYSCTL_CIPHER,
+};
+
+#define CLK(_dev, _con, _clk)	\
+{ .dev_id = (_dev), .con_id = (_con), .clk = (_clk) },
+
+static struct clk_lookup mcs814x_chip_clks[] = {
+	CLK("cpu", NULL, &clk_cpu)
+	CLK("sys", NULL, &clk_sys)
+	CLK("sdram", NULL, &clk_sdram)
+	/* 32-bits timer0 */
+	CLK("timer0", NULL, &clk_timer0)
+	/* 16-bits timer1 */
+	CLK("timer1", NULL, &clk_timer1_2)
+	/* 64-bits timer2, same as timer 1 */
+	CLK("timer2", NULL, &clk_timer1_2)
+	CLK(NULL, "wdt", &clk_wdt)
+	CLK(NULL, "emac", &clk_emac)
+	CLK(NULL, "ephy", &clk_ephy)
+	CLK(NULL, "cipher", &clk_cipher)
+};
+
+static void local_clk_disable(struct clk *clk)
+{
+	WARN_ON(!clk->usecount);
+
+	if (clk->usecount > 0) {
+		clk->usecount--;
+
+		if ((clk->usecount == 0) && (clk->ops->enable))
+			clk->ops->enable(clk, 0);
+
+		if (clk->parent)
+			local_clk_disable(clk->parent);
+	}
+}
+
+static int local_clk_enable(struct clk *clk)
+{
+	int ret = 0;
+
+	if (clk->parent)
+		ret = local_clk_enable(clk->parent);
+
+	if (ret)
+		return ret;
+
+	if ((clk->usecount == 0) && (clk->ops->enable))
+		ret = clk->ops->enable(clk, 1);
+
+	if (!ret)
+		clk->usecount++;
+	else if (clk->parent && clk->parent->ops->enable)
+		local_clk_disable(clk->parent);
+
+	return ret;
+}
+
+int clk_enable(struct clk *clk)
+{
+	int ret;
+	unsigned long flags;
+
+	spin_lock_irqsave(&clocks_lock, flags);
+	ret = local_clk_enable(clk);
+	spin_unlock_irqrestore(&clocks_lock, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL(clk_enable);
+
+void clk_disable(struct clk *clk)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&clocks_lock, flags);
+	local_clk_disable(clk);
+	spin_unlock_irqrestore(&clocks_lock, flags);
+}
+EXPORT_SYMBOL(clk_disable);
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+	if (unlikely(IS_ERR_OR_NULL(clk)))
+		return 0;
+
+	if (clk->rate)
+		return clk->rate;
+
+	if (clk->ops && clk->ops->get_rate)
+		return clk->ops->get_rate(clk);
+
+	return clk_get_rate(clk->parent);
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+struct clk *clk_get_parent(struct clk *clk)
+{
+	unsigned long flags;
+
+	if (unlikely(IS_ERR_OR_NULL(clk)))
+		return NULL;
+
+	if (!clk->ops || !clk->ops->get_parent)
+		return clk->parent;
+
+	spin_lock_irqsave(&clocks_lock, flags);
+	clk->parent = clk->ops->get_parent(clk);
+	spin_unlock_irqrestore(&clocks_lock, flags);
+
+	return clk->parent;
+}
+EXPORT_SYMBOL(clk_get_parent);
+
+void __init mcs814x_clk_init(void)
+{
+	u32 bs1;
+	u8 cpu_freq;
+
+	clkdev_add_table(mcs814x_chip_clks, ARRAY_SIZE(mcs814x_chip_clks));
+
+	/* read the bootstrap registers to know the exact clocking scheme */
+	bs1 = readl_relaxed(mcs814x_sysdbg_base + SYSDBG_BS1);
+	cpu_freq = (bs1 >> CPU_FREQ_SHIFT) & CPU_FREQ_MASK;
+
+	pr_info("CPU frequency: %lu (kHz)\n", cpu_freq_table[cpu_freq]);
+	clk_cpu.rate = cpu_freq * KHZ;
+
+	/* read SDRAM frequency */
+	if (bs1 & SDRAM_FREQ_BIT)
+		clk_sdram.rate = 100 * MHZ;
+	else
+		clk_sdram.rate = 133 * MHZ;
+
+	pr_info("SDRAM frequency: %lu (MHz)\n", clk_sdram.rate / MHZ);
+}
+