MIPS: ralink: adds support for RT2880 SoC family

Add support code for rt2880 SOC.

The code detects the SoC and registers the clk / pinmux settings.

Signed-off-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/5176/
diff --git a/arch/mips/ralink/rt288x.c b/arch/mips/ralink/rt288x.c
new file mode 100644
index 0000000..1e0788e
--- /dev/null
+++ b/arch/mips/ralink/rt288x.c
@@ -0,0 +1,139 @@
+/*
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * Parts of this file are based on Ralink's 2.6.21 BSP
+ *
+ * Copyright (C) 2008-2011 Gabor Juhos <juhosg@openwrt.org>
+ * Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
+ * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+
+#include <asm/mipsregs.h>
+#include <asm/mach-ralink/ralink_regs.h>
+#include <asm/mach-ralink/rt288x.h>
+
+#include "common.h"
+
+static struct ralink_pinmux_grp mode_mux[] = {
+	{
+		.name = "i2c",
+		.mask = RT2880_GPIO_MODE_I2C,
+		.gpio_first = 1,
+		.gpio_last = 2,
+	}, {
+		.name = "spi",
+		.mask = RT2880_GPIO_MODE_SPI,
+		.gpio_first = 3,
+		.gpio_last = 6,
+	}, {
+		.name = "uartlite",
+		.mask = RT2880_GPIO_MODE_UART0,
+		.gpio_first = 7,
+		.gpio_last = 14,
+	}, {
+		.name = "jtag",
+		.mask = RT2880_GPIO_MODE_JTAG,
+		.gpio_first = 17,
+		.gpio_last = 21,
+	}, {
+		.name = "mdio",
+		.mask = RT2880_GPIO_MODE_MDIO,
+		.gpio_first = 22,
+		.gpio_last = 23,
+	}, {
+		.name = "sdram",
+		.mask = RT2880_GPIO_MODE_SDRAM,
+		.gpio_first = 24,
+		.gpio_last = 39,
+	}, {
+		.name = "pci",
+		.mask = RT2880_GPIO_MODE_PCI,
+		.gpio_first = 40,
+		.gpio_last = 71,
+	}, {0}
+};
+
+static void rt288x_wdt_reset(void)
+{
+	u32 t;
+
+	/* enable WDT reset output on pin SRAM_CS_N */
+	t = rt_sysc_r32(SYSC_REG_CLKCFG);
+	t |= CLKCFG_SRAM_CS_N_WDT;
+	rt_sysc_w32(t, SYSC_REG_CLKCFG);
+}
+
+struct ralink_pinmux rt_gpio_pinmux = {
+	.mode = mode_mux,
+	.wdt_reset = rt288x_wdt_reset,
+};
+
+void __init ralink_clk_init(void)
+{
+	unsigned long cpu_rate;
+	u32 t = rt_sysc_r32(SYSC_REG_SYSTEM_CONFIG);
+	t = ((t >> SYSTEM_CONFIG_CPUCLK_SHIFT) & SYSTEM_CONFIG_CPUCLK_MASK);
+
+	switch (t) {
+	case SYSTEM_CONFIG_CPUCLK_250:
+		cpu_rate = 250000000;
+		break;
+	case SYSTEM_CONFIG_CPUCLK_266:
+		cpu_rate = 266666667;
+		break;
+	case SYSTEM_CONFIG_CPUCLK_280:
+		cpu_rate = 280000000;
+		break;
+	case SYSTEM_CONFIG_CPUCLK_300:
+		cpu_rate = 300000000;
+		break;
+	}
+
+	ralink_clk_add("cpu", cpu_rate);
+	ralink_clk_add("300100.timer", cpu_rate / 2);
+	ralink_clk_add("300120.watchdog", cpu_rate / 2);
+	ralink_clk_add("300500.uart", cpu_rate / 2);
+	ralink_clk_add("300c00.uartlite", cpu_rate / 2);
+	ralink_clk_add("400000.ethernet", cpu_rate / 2);
+}
+
+void __init ralink_of_remap(void)
+{
+	rt_sysc_membase = plat_of_remap_node("ralink,rt2880-sysc");
+	rt_memc_membase = plat_of_remap_node("ralink,rt2880-memc");
+
+	if (!rt_sysc_membase || !rt_memc_membase)
+		panic("Failed to remap core resources");
+}
+
+void prom_soc_init(struct ralink_soc_info *soc_info)
+{
+	void __iomem *sysc = (void __iomem *) KSEG1ADDR(RT2880_SYSC_BASE);
+	const char *name;
+	u32 n0;
+	u32 n1;
+	u32 id;
+
+	n0 = __raw_readl(sysc + SYSC_REG_CHIP_NAME0);
+	n1 = __raw_readl(sysc + SYSC_REG_CHIP_NAME1);
+	id = __raw_readl(sysc + SYSC_REG_CHIP_ID);
+
+	if (n0 == RT2880_CHIP_NAME0 && n1 == RT2880_CHIP_NAME1) {
+		soc_info->compatible = "ralink,r2880-soc";
+		name = "RT2880";
+	} else {
+		panic("rt288x: unknown SoC, n0:%08x n1:%08x", n0, n1);
+	}
+
+	snprintf(soc_info->sys_type, RAMIPS_SYS_TYPE_LEN,
+		"Ralink %s id:%u rev:%u",
+		name,
+		(id >> CHIP_ID_ID_SHIFT) & CHIP_ID_ID_MASK,
+		(id & CHIP_ID_REV_MASK));
+}