3 files changed, 171 insertions, 0 deletions
diff --git a/arch/sh/kernel/cpu/irq/Makefile b/arch/sh/kernel/cpu/irq/Makefile
new file mode 100644
index 000000000..e4578cde4
--- /dev/null
+++ b/arch/sh/kernel/cpu/irq/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the Linux/SuperH CPU-specific IRQ handlers.
+#
+obj-y					+= imask.o
+obj-$(CONFIG_CPU_HAS_IPR_IRQ)		+= ipr.o
diff --git a/arch/sh/kernel/cpu/irq/imask.c b/arch/sh/kernel/cpu/irq/imask.c
new file mode 100644
index 000000000..572585c3f
--- /dev/null
+++ b/arch/sh/kernel/cpu/irq/imask.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * arch/sh/kernel/cpu/irq/imask.c
+ *
+ * Copyright (C) 1999, 2000  Niibe Yutaka
+ *
+ * Simple interrupt handling using IMASK of SR register.
+ *
+ */
+/* NOTE: Will not work on level 15 */
+#include <linux/ptrace.h>
+#include <linux/errno.h>
+#include <linux/kernel_stat.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+#include <linux/spinlock.h>
+#include <linux/cache.h>
+#include <linux/irq.h>
+#include <linux/bitmap.h>
+#include <asm/irq.h>
+
+/* Bitmap of IRQ masked */
+#define IMASK_PRIORITY	15
+
+static DECLARE_BITMAP(imask_mask, IMASK_PRIORITY);
+static int interrupt_priority;
+
+static inline void set_interrupt_registers(int ip)
+{
+	unsigned long __dummy;
+
+	asm volatile(
+#ifdef CONFIG_CPU_HAS_SR_RB
+		     "ldc	%2, r6_bank\n\t"
+#endif
+		     "stc	sr, %0\n\t"
+		     "and	#0xf0, %0\n\t"
+		     "shlr2	%0\n\t"
+		     "cmp/eq	#0x3c, %0\n\t"
+		     "bt/s	1f	! CLI-ed\n\t"
+		     " stc	sr, %0\n\t"
+		     "and	%1, %0\n\t"
+		     "or	%2, %0\n\t"
+		     "ldc	%0, sr\n"
+		     "1:"
+		     : "=&z" (__dummy)
+		     : "r" (~0xf0), "r" (ip << 4)
+		     : "t");
+}
+
+static void mask_imask_irq(struct irq_data *data)
+{
+	unsigned int irq = data->irq;
+
+	clear_bit(irq, imask_mask);
+	if (interrupt_priority < IMASK_PRIORITY - irq)
+		interrupt_priority = IMASK_PRIORITY - irq;
+	set_interrupt_registers(interrupt_priority);
+}
+
+static void unmask_imask_irq(struct irq_data *data)
+{
+	unsigned int irq = data->irq;
+
+	set_bit(irq, imask_mask);
+	interrupt_priority = IMASK_PRIORITY -
+		find_first_zero_bit(imask_mask, IMASK_PRIORITY);
+	set_interrupt_registers(interrupt_priority);
+}
+
+static struct irq_chip imask_irq_chip = {
+	.name		= "SR.IMASK",
+	.irq_mask	= mask_imask_irq,
+	.irq_unmask	= unmask_imask_irq,
+	.irq_mask_ack	= mask_imask_irq,
+};
+
+void make_imask_irq(unsigned int irq)
+{
+	irq_set_chip_and_handler_name(irq, &imask_irq_chip, handle_level_irq,
+				      "level");
+}
diff --git a/arch/sh/kernel/cpu/irq/ipr.c b/arch/sh/kernel/cpu/irq/ipr.c
new file mode 100644
index 000000000..d41bce71f
--- /dev/null
+++ b/arch/sh/kernel/cpu/irq/ipr.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Interrupt handling for IPR-based IRQ.
+ *
+ * Copyright (C) 1999  Niibe Yutaka & Takeshi Yaegashi
+ * Copyright (C) 2000  Kazumoto Kojima
+ * Copyright (C) 2003  Takashi Kusuda <kusuda-takashi@hitachi-ul.co.jp>
+ * Copyright (C) 2006  Paul Mundt
+ *
+ * Supported system:
+ *	On-chip supporting modules (TMU, RTC, etc.).
+ *	On-chip supporting modules for SH7709/SH7709A/SH7729.
+ *	Hitachi SolutionEngine external I/O:
+ *		MS7709SE01, MS7709ASE01, and MS7750SE01
+ */
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/topology.h>
+
+static inline struct ipr_desc *get_ipr_desc(struct irq_data *data)
+{
+	struct irq_chip *chip = irq_data_get_irq_chip(data);
+	return container_of(chip, struct ipr_desc, chip);
+}
+
+static void disable_ipr_irq(struct irq_data *data)
+{
+	struct ipr_data *p = irq_data_get_irq_chip_data(data);
+	unsigned long addr = get_ipr_desc(data)->ipr_offsets[p->ipr_idx];
+	/* Set the priority in IPR to 0 */
+	__raw_writew(__raw_readw(addr) & (0xffff ^ (0xf << p->shift)), addr);
+	(void)__raw_readw(addr);	/* Read back to flush write posting */
+}
+
+static void enable_ipr_irq(struct irq_data *data)
+{
+	struct ipr_data *p = irq_data_get_irq_chip_data(data);
+	unsigned long addr = get_ipr_desc(data)->ipr_offsets[p->ipr_idx];
+	/* Set priority in IPR back to original value */
+	__raw_writew(__raw_readw(addr) | (p->priority << p->shift), addr);
+}
+
+/*
+ * The shift value is now the number of bits to shift, not the number of
+ * bits/4. This is to make it easier to read the value directly from the
+ * datasheets. The IPR address is calculated using the ipr_offset table.
+ */
+void register_ipr_controller(struct ipr_desc *desc)
+{
+	int i;
+
+	desc->chip.irq_mask = disable_ipr_irq;
+	desc->chip.irq_unmask = enable_ipr_irq;
+
+	for (i = 0; i < desc->nr_irqs; i++) {
+		struct ipr_data *p = desc->ipr_data + i;
+		int res;
+
+		BUG_ON(p->ipr_idx >= desc->nr_offsets);
+		BUG_ON(!desc->ipr_offsets[p->ipr_idx]);
+
+		res = irq_alloc_desc_at(p->irq, numa_node_id());
+		if (unlikely(res != p->irq && res != -EEXIST)) {
+			printk(KERN_INFO "can not get irq_desc for %d\n",
+			       p->irq);
+			continue;
+		}
+
+		disable_irq_nosync(p->irq);
+		irq_set_chip_and_handler_name(p->irq, &desc->chip,
+					      handle_level_irq, "level");
+		irq_set_chip_data(p->irq, p);
+		disable_ipr_irq(irq_get_irq_data(p->irq));
+	}
+}
+EXPORT_SYMBOL(register_ipr_controller);