RISC-V: Init and Halt Code

This contains the various __init C functions, the initial assembly
kernel entry point, and the code to reset the system.  When a file was
init-related this patch contains the entire file.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>

1 files changed, 39 insertions, 0 deletions

diff --git a/arch/riscv/kernel/irq.c b/arch/riscv/kernel/irq.c
new file mode 100644
index 000000000000..328718e8026e
--- /dev/null
+++ b/arch/riscv/kernel/irq.c
@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ *   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, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+
+#ifdef CONFIG_RISCV_INTC
+#include <linux/irqchip/irq-riscv-intc.h>
+#endif
+
+void __init init_IRQ(void)
+{
+	irqchip_init();
+}
+
+asmlinkage void __irq_entry do_IRQ(unsigned int cause, struct pt_regs *regs)
+{
+#ifdef CONFIG_RISCV_INTC
+	/*
+	 * FIXME: We don't want a direct call to riscv_intc_irq here.  The plan
+	 * is to put an IRQ domain here and let the interrupt controller
+	 * register with that, but I poked around the arm64 code a bit and
+	 * there might be a better way to do it (ie, something fully generic).
+	 */
+	riscv_intc_irq(cause, regs);
+#endif
+}