MIPS: Loongson 1B: Add board support

Adds basic platform devices for Loongson 1B, including serial port,
ethernet, USB, RTC and interrupt handler.

The Loongson 1B UART is compatible with NS16550A, the Loongson 1B GMAC is
built around a Synopsys IP Core.

Use normal instead of enhanced descriptors.

Thanks to Giuseppe for updating the normal descriptor in stmmac driver.
Thanks to Zhao Zhang for implementing the RTC driver.

Signed-off-by: Kelvin Cheung <keguang.zhang@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: wuzhangjin@gmail.com
Cc: zhzhl555@gmail.com
Cc: Kelvin Cheung <keguang.zhang@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/4133/
Patchwork: https://patchwork.linux-mips.org/patch/4134/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 165 insertions, 0 deletions

diff --git a/arch/mips/loongson1/common/clock.c b/arch/mips/loongson1/common/clock.c
new file mode 100644
index 000000000000..2d98fb030596
--- /dev/null
+++ b/arch/mips/loongson1/common/clock.c
@@ -0,0 +1,165 @@
+/*
+ * Copyright (c) 2011 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/module.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <asm/clock.h>
+#include <asm/time.h>
+
+#include <loongson1.h>
+
+static LIST_HEAD(clocks);
+static DEFINE_MUTEX(clocks_mutex);
+
+struct clk *clk_get(struct device *dev, const char *name)
+{
+	struct clk *c;
+	struct clk *ret = NULL;
+
+	mutex_lock(&clocks_mutex);
+	list_for_each_entry(c, &clocks, node) {
+		if (!strcmp(c->name, name)) {
+			ret = c;
+			break;
+		}
+	}
+	mutex_unlock(&clocks_mutex);
+
+	return ret;
+}
+EXPORT_SYMBOL(clk_get);
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+	return clk->rate;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+static void pll_clk_init(struct clk *clk)
+{
+	u32 pll;
+
+	pll = __raw_readl(LS1X_CLK_PLL_FREQ);
+	clk->rate = (12 + (pll & 0x3f)) * 33 / 2
+			+ ((pll >> 8) & 0x3ff) * 33 / 1024 / 2;
+	clk->rate *= 1000000;
+}
+
+static void cpu_clk_init(struct clk *clk)
+{
+	u32 pll, ctrl;
+
+	pll = clk_get_rate(clk->parent);
+	ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_CPU;
+	clk->rate = pll / (ctrl >> DIV_CPU_SHIFT);
+}
+
+static void ddr_clk_init(struct clk *clk)
+{
+	u32 pll, ctrl;
+
+	pll = clk_get_rate(clk->parent);
+	ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_DDR;
+	clk->rate = pll / (ctrl >> DIV_DDR_SHIFT);
+}
+
+static void dc_clk_init(struct clk *clk)
+{
+	u32 pll, ctrl;
+
+	pll = clk_get_rate(clk->parent);
+	ctrl = __raw_readl(LS1X_CLK_PLL_DIV) & DIV_DC;
+	clk->rate = pll / (ctrl >> DIV_DC_SHIFT);
+}
+
+static struct clk_ops pll_clk_ops = {
+	.init	= pll_clk_init,
+};
+
+static struct clk_ops cpu_clk_ops = {
+	.init	= cpu_clk_init,
+};
+
+static struct clk_ops ddr_clk_ops = {
+	.init	= ddr_clk_init,
+};
+
+static struct clk_ops dc_clk_ops = {
+	.init	= dc_clk_init,
+};
+
+static struct clk pll_clk = {
+	.name	= "pll",
+	.ops	= &pll_clk_ops,
+};
+
+static struct clk cpu_clk = {
+	.name	= "cpu",
+	.parent = &pll_clk,
+	.ops	= &cpu_clk_ops,
+};
+
+static struct clk ddr_clk = {
+	.name	= "ddr",
+	.parent = &pll_clk,
+	.ops	= &ddr_clk_ops,
+};
+
+static struct clk dc_clk = {
+	.name	= "dc",
+	.parent = &pll_clk,
+	.ops	= &dc_clk_ops,
+};
+
+int clk_register(struct clk *clk)
+{
+	mutex_lock(&clocks_mutex);
+	list_add(&clk->node, &clocks);
+	if (clk->ops->init)
+		clk->ops->init(clk);
+	mutex_unlock(&clocks_mutex);
+
+	return 0;
+}
+EXPORT_SYMBOL(clk_register);
+
+static struct clk *ls1x_clks[] = {
+	&pll_clk,
+	&cpu_clk,
+	&ddr_clk,
+	&dc_clk,
+};
+
+int __init ls1x_clock_init(void)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(ls1x_clks); i++)
+		clk_register(ls1x_clks[i]);
+
+	return 0;
+}
+
+void __init plat_time_init(void)
+{
+	struct clk *clk;
+
+	/* Initialize LS1X clocks */
+	ls1x_clock_init();
+
+	/* setup mips r4k timer */
+	clk = clk_get(NULL, "cpu");
+	if (IS_ERR(clk))
+		panic("unable to get dc clock, err=%ld", PTR_ERR(clk));
+
+	mips_hpt_frequency = clk_get_rate(clk) / 2;
+}