ARM: initial DTS support for km_kirkwood

This is a first attempt to support the km_kirkwood reference design with
a device tree. This km_kirkwood design is present in many Keymile
products. It is based on the Marvell Bobcat SOC which integrates a
Kirkwood CPU next to a big L2 Ethernet Switch. The Kirkwood in the SOC
is very similar to the "normal" one, but there are a few differences.

This initial support is minimal: the kernel can boot with network
(ge0), serial port and NAND functional.

Signed-off-by: Valentin Longchamp <valentin.longchamp@keymile.com>
Cc: Holger Brunck <holger.brunck@keymile.com>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

arch/arm/boot/dts/kirkwood-km_kirkwood.dts

@@ -0,0 +1,29 @@
+/dts-v1/;
+
+/include/ "kirkwood.dtsi"
+
+/ {
+	model = "Keymile Kirkwood Reference Design";
+	compatible = "keymile,km_kirkwood", "marvell,kirkwood-98DX4122", "marvell,kirkwood";
+
+	memory {
+		device_type = "memory";
+		reg = <0x00000000 0x08000000>;
+	};
+
+	chosen {
+		bootargs = "console=ttyS0,115200n8 earlyprintk";
+	};
+
+	ocp@f1000000 {
+		serial@12000 {
+			clock-frequency = <200000000>;
+			status = "ok";
+		};
+
+		nand@3000000 {
+			status = "ok";
+			chip-delay = <25>;
+		};
+	};
+};

arch/arm/mach-kirkwood/Kconfig

@@ -123,6 +123,13 @@ config MACH_IOMEGA_IX2_200_DT
 	  Say 'Y' here if you want your kernel to support the
 	  Iomega StorCenter ix2-200 (Flattened Device Tree).
 
+config MACH_KM_KIRKWOOD_DT
+	bool "Keymile Kirkwood Reference Design (Flattened Device Tree)"
+	select ARCH_KIRKWOOD_DT
+	help
+	  Say 'Y' here if you want your kernel to support the
+	  Keymile Kirkwood Reference Desgin, using Flattened Device Tree.
+
 config MACH_TS219
 	bool "QNAP TS-110, TS-119, TS-119P+, TS-210, TS-219, TS-219P and TS-219P+ Turbo NAS"
 	help

arch/arm/mach-kirkwood/Makefile

@@ -30,3 +30,4 @@ obj-$(CONFIG_MACH_DOCKSTAR_DT)		+= board-dockstar.o
 obj-$(CONFIG_MACH_GOFLEXNET_DT)		+= board-goflexnet.o
 obj-$(CONFIG_MACH_LSXL_DT)		+= board-lsxl.o
 obj-$(CONFIG_MACH_IOMEGA_IX2_200_DT)	+= board-iomega_ix2_200.o
+obj-$(CONFIG_MACH_KM_KIRKWOOD_DT)	+= board-km_kirkwood.o

arch/arm/mach-kirkwood/Makefile.boot

@@ -14,3 +14,4 @@ dtb-$(CONFIG_MACH_LSXL_DT) += kirkwood-lschlv2.dtb
 dtb-$(CONFIG_MACH_LSXL_DT) += kirkwood-lsxhl.dtb
 dtb-$(CONFIG_MACH_IOMEGA_IX2_200_DT) += kirkwood-iomega_ix2_200.dtb
 dtb-$(CONFIG_MACH_DOCKSTAR_DT) += kirkwood-dockstar.dtb
+dtb-$(CONFIG_MACH_KM_KIRKWOOD_DT) += kirkwood-km_kirkwood.dtb

arch/arm/mach-kirkwood/board-dt.c

@@ -93,6 +93,9 @@ static void __init kirkwood_dt_init(void)
 	if (of_machine_is_compatible("iom,ix2-200"))
 		iomega_ix2_200_init();
 
+	if (of_machine_is_compatible("keymile,km_kirkwood"))
+		km_kirkwood_init();
+
 	of_platform_populate(NULL, kirkwood_dt_match_table,
 			     kirkwood_auxdata_lookup, NULL);
 }
@@ -108,6 +111,7 @@ static const char *kirkwood_dt_board_compat[] = {
 	"seagate,goflexnet",
 	"buffalo,lsxl",
 	"iom,ix2-200",
+	"keymile,km_kirkwood",
 	NULL
 };
 

arch/arm/mach-kirkwood/board-km_kirkwood.c

@@ -0,0 +1,57 @@
+/*
+ * Copyright 2012 2012 KEYMILE AG, CH-3097 Bern
+ * Valentin Longchamp <valentin.longchamp@keymile.com>
+ *
+ * arch/arm/mach-kirkwood/board-km_kirkwood.c
+ *
+ * Keymile km_kirkwood Reference Desing Init for drivers not converted to
+ * flattened device tree yet.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/mv643xx_eth.h>
+#include <linux/clk.h>
+#include <linux/clk-private.h>
+#include "common.h"
+#include "mpp.h"
+
+static struct mv643xx_eth_platform_data km_kirkwood_ge00_data = {
+	.phy_addr	= MV643XX_ETH_PHY_ADDR(0),
+};
+
+static unsigned int km_kirkwood_mpp_config[] __initdata = {
+	MPP8_GPIO,	/* I2C SDA */
+	MPP9_GPIO,	/* I2C SCL */
+	0
+};
+
+void __init km_kirkwood_init(void)
+{
+	struct clk *sata_clk;
+	/*
+	 * Basic setup. Needs to be called early.
+	 */
+	kirkwood_mpp_conf(km_kirkwood_mpp_config);
+
+	/*
+	 * Our variant of kirkwood (integrated in the Bobcat) hangs on accessing
+	 * SATA bits (14-15) of the Clock Gating Control Register. Since these
+	 * devices are also not present in this variant, their clocks get
+	 * disabled because unused when clk_disable_unused() gets called.
+	 * That's why we change the flags to these clocks to CLK_IGNORE_UNUSED
+	 */
+	sata_clk = clk_get_sys("sata_mv.0", "0");
+	if (!IS_ERR(sata_clk))
+		sata_clk->flags |= CLK_IGNORE_UNUSED;
+	sata_clk = clk_get_sys("sata_mv.0", "1");
+	if (!IS_ERR(sata_clk))
+		sata_clk->flags |= CLK_IGNORE_UNUSED;
+
+	kirkwood_ehci_init();
+	kirkwood_ge00_init(&km_kirkwood_ge00_data);
+}

arch/arm/mach-kirkwood/common.h

@@ -106,6 +106,12 @@ void iomega_ix2_200_init(void);
 static inline void iomega_ix2_200_init(void) {};
 #endif
 
+#ifdef CONFIG_MACH_KM_KIRKWOOD_DT
+void km_kirkwood_init(void);
+#else
+static inline void km_kirkwood_init(void) {};
+#endif
+
 /* early init functions not converted to fdt yet */
 char *kirkwood_id(void);
 void kirkwood_l2_init(void);