[mcs814x] add Moschip MSC814x support

This target currently only supports Moschip's MCS8140 SoC, but support
for other chips in the same family (MCS8142, MCS8144) will be easy to add.

Target support is entirely using Device Tree for probing peripherals.
Drivers support include:
- PCI
- USB 1 & 2
- watchdog
- random number generator
- UART
- timer
- internal Ethernet PHY
- Ethernet MAC core

Support for the following boards is included using Device Tree
- Devolo dLAN USB Extender
- Tigal RBT-832

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@32462 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 280 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..b5d2a445b
--- /dev/null
+++ b/target/linux/mcs814x/files-3.3/arch/arm/mach-mcs814x/clock.c
@@ -0,0 +1,280 @@
+/*
+ * 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/hardware.h>
+
+/* System configuration registers offsets */
+#define SYSDBG_BS1	0x00
+#define SYSDBG_SYSCTL	0x08
+#define  SYSCTL_EMAC	(1 << 0)
+#define  SYSCTL_CIPHER	(1 << 16)
+#define SYSDBG_PLL_CTL	0x3C
+
+#define CPU_FREQ_SHIFT	27
+#define CPU_FREQ_MASK	0x0F
+#define SDRAM_FREQ_BIT	(1 << 22)
+
+#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 */
+	void __iomem *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 = __raw_readl(clk->enable_reg);
+	if (!enable)
+		tmp &= ~clk->enable_mask;
+	else
+		tmp |= clk->enable_mask;
+
+	__raw_writel(tmp, 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	= (void __iomem *)(_CONFADDR_SYSDBG + SYSDBG_SYSCTL),
+	.enable_mask	= SYSCTL_EMAC,
+};
+
+static struct clk clk_ephy = {
+	.ops		= &default_clk_ops,
+	.enable_reg	= (void __iomem *)(_CONFADDR_SYSDBG + SYSDBG_PLL_CTL),
+	.enable_mask	= ~(1 << 0),
+};
+
+static struct clk clk_cipher = {
+	.ops		= &default_clk_ops,
+	.enable_reg	= (void __iomem *)(_CONFADDR_SYSDBG + 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 = __raw_readl(_CONFADDR_SYSDBG + 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);
+}
+