[PATCH v3 4/8] MIPS: mscc: Add initial support for Microsemi MIPS SoCs

[Alexandre Belloni]

Introduce support for the MIPS based Microsemi Ocelot SoCs.
As the plan is to have all SoCs supported only using device tree, the
mach directory is simply called mscc.

Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
---
 arch/mips/Kbuild.platforms |   1 +
 arch/mips/Kconfig          |  24 ++++++++++
 arch/mips/mscc/Makefile    |  11 +++++
 arch/mips/mscc/Platform    |  12 +++++
 arch/mips/mscc/setup.c     | 106 +++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 154 insertions(+)
 create mode 100644 arch/mips/mscc/Makefile
 create mode 100644 arch/mips/mscc/Platform
 create mode 100644 arch/mips/mscc/setup.c

diff --git a/arch/mips/Kbuild.platforms b/arch/mips/Kbuild.platforms
index ac7ad54f984f..b3b2f8dc91db 100644
--- a/arch/mips/Kbuild.platforms
+++ b/arch/mips/Kbuild.platforms
@@ -18,6 +18,7 @@ platforms += lantiq
 platforms += lasat
 platforms += loongson32
 platforms += loongson64
+platforms += mscc
 platforms += mti-malta
 platforms += netlogic
 platforms += paravirt
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 350a990fc719..a9db028a0338 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -527,6 +527,30 @@ config MIPS_MALTA
 	  This enables support for the MIPS Technologies Malta evaluation
 	  board.
 
+config MSCC_OCELOT
+	bool "Microsemi Ocelot architecture"
+	select BOOT_RAW
+	select CEVT_R4K
+	select CSRC_R4K
+	select IRQ_MIPS_CPU
+	select DMA_NONCOHERENT
+	select SYS_HAS_CPU_MIPS32_R2
+	select SYS_SUPPORTS_32BIT_KERNEL
+	select SYS_SUPPORTS_BIG_ENDIAN
+	select SYS_SUPPORTS_LITTLE_ENDIAN
+	select SYS_HAS_EARLY_PRINTK
+	select USE_GENERIC_EARLY_PRINTK_8250
+	select MSCC_OCELOT_IRQ
+	select PINCTRL
+	select GPIOLIB
+	select COMMON_CLK
+	select USE_OF
+	select BUILTIN_DTB
+	select LIBFDT
+	help
+	  This enables support for the Microsemi Ocelot architecture.
+	  It builds a generic DT-based kernel image.
+
 config MACH_PIC32
 	bool "Microchip PIC32 Family"
 	help
diff --git a/arch/mips/mscc/Makefile b/arch/mips/mscc/Makefile
new file mode 100644
index 000000000000..c96b13546730
--- /dev/null
+++ b/arch/mips/mscc/Makefile
@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: (GPL-2.0 OR MIT)
+#
+# Microsemi MIPS SoC support
+#
+# License: Dual MIT/GPL
+# Copyright (c) 2017 Microsemi Corporation
+
+#
+# Makefile for the Microsemi MIPS SoCs
+#
+obj-y := setup.o
diff --git a/arch/mips/mscc/Platform b/arch/mips/mscc/Platform
new file mode 100644
index 000000000000..9ae874c8f136
--- /dev/null
+++ b/arch/mips/mscc/Platform
@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: (GPL-2.0 OR MIT)
+#
+# Microsemi MIPS SoC support
+#
+# License: Dual MIT/GPL
+# Copyright (c) 2017 Microsemi Corporation
+
+#
+# Microsemi Ocelot board(s)
+#
+platform-$(CONFIG_MSCC_OCELOT) += mscc/
+load-$(CONFIG_MSCC_OCELOT)	 += 0x80100000
diff --git a/arch/mips/mscc/setup.c b/arch/mips/mscc/setup.c
new file mode 100644
index 000000000000..77803edd7bfd
--- /dev/null
+++ b/arch/mips/mscc/setup.c
@@ -0,0 +1,106 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * Microsemi MIPS SoC support
+ *
+ * License: Dual MIT/GPL
+ * Copyright (c) 2017 Microsemi Corporation
+ */
+#include <linux/delay.h>
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/libfdt.h>
+#include <linux/of_fdt.h>
+#include <linux/of_platform.h>
+#include <linux/reboot.h>
+
+#include <asm/time.h>
+#include <asm/idle.h>
+#include <asm/prom.h>
+#include <asm/reboot.h>
+
+static void __init ocelot_earlyprintk_init(void)
+{
+	void __iomem *uart_base;
+
+	uart_base = ioremap_nocache(0x70100000, 0x0f);
+	setup_8250_early_printk_port((unsigned long)uart_base, 2, 50000);
+}
+
+void __init prom_init(void)
+{
+	/* Sanity check for defunct bootloader */
+	if (fw_arg0 < 10 && (fw_arg1 & 0xFFF00000) == 0x80000000) {
+		unsigned int prom_argc = fw_arg0;
+		const char **prom_argv = (const char **)fw_arg1;
+
+		if (prom_argc > 1 && strlen(prom_argv[1]) > 0)
+			/* ignore all built-in args if any f/w args given */
+			strcpy(arcs_cmdline, prom_argv[1]);
+	}
+}
+
+void __init prom_free_prom_memory(void)
+{
+}
+
+unsigned int get_c0_compare_int(void)
+{
+	return CP0_LEGACY_COMPARE_IRQ;
+}
+
+void __init plat_time_init(void)
+{
+	struct device_node *np;
+	u32 freq;
+
+	np = of_find_node_by_name(NULL, "cpus");
+	if (!np)
+		panic("missing 'cpus' DT node");
+	if (of_property_read_u32(np, "mips-hpt-frequency", &freq) < 0)
+		panic("missing 'mips-hpt-frequency' property");
+	of_node_put(np);
+
+	mips_hpt_frequency = freq;
+}
+
+void __init arch_init_irq(void)
+{
+	irqchip_init();
+}
+
+const char *get_system_type(void)
+{
+	return "Microsemi Ocelot";
+}
+
+static void __init ocelot_late_init(void)
+{
+	ocelot_earlyprintk_init();
+}
+
+extern void (*late_time_init)(void);
+
+void __init plat_mem_setup(void)
+{
+	/* This has to be done so late because ioremap needs to work */
+	late_time_init = ocelot_late_init;
+
+	__dt_setup_arch(__dtb_start);
+}
+
+void __init device_tree_init(void)
+{
+	if (!initial_boot_params)
+		return;
+
+	unflatten_and_copy_device_tree();
+}
+
+static int __init populate_machine(void)
+{
+	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
+	return 0;
+}
+arch_initcall(populate_machine);
-- 
2.15.1