Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 339 insertions, 0 deletions

diff --git a/arch/mips/sgi-ip22/ip22-int.c b/arch/mips/sgi-ip22/ip22-int.c
new file mode 100644
index 000000000..3804895fa
--- /dev/null
+++ b/arch/mips/sgi-ip22/ip22-int.c
@@ -0,0 +1,339 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ip22-int.c: Routines for generic manipulation of the INT[23] ASIC
+ *	       found on INDY and Indigo2 workstations.
+ *
+ * Copyright (C) 1996 David S. Miller (davem@davemloft.net)
+ * Copyright (C) 1997, 1998 Ralf Baechle (ralf@gnu.org)
+ * Copyright (C) 1999 Andrew R. Baker (andrewb@uab.edu)
+ *		      - Indigo2 changes
+ *		      - Interrupt handling fixes
+ * Copyright (C) 2001, 2003 Ladislav Michl (ladis@linux-mips.org)
+ */
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/kernel_stat.h>
+#include <linux/interrupt.h>
+#include <linux/ftrace.h>
+
+#include <asm/irq_cpu.h>
+#include <asm/sgi/hpc3.h>
+#include <asm/sgi/ip22.h>
+
+/* So far nothing hangs here */
+#undef USE_LIO3_IRQ
+
+struct sgint_regs *sgint;
+
+static char lc0msk_to_irqnr[256];
+static char lc1msk_to_irqnr[256];
+static char lc2msk_to_irqnr[256];
+static char lc3msk_to_irqnr[256];
+
+extern int ip22_eisa_init(void);
+
+static void enable_local0_irq(struct irq_data *d)
+{
+	/* don't allow mappable interrupt to be enabled from setup_irq,
+	 * we have our own way to do so */
+	if (d->irq != SGI_MAP_0_IRQ)
+		sgint->imask0 |= (1 << (d->irq - SGINT_LOCAL0));
+}
+
+static void disable_local0_irq(struct irq_data *d)
+{
+	sgint->imask0 &= ~(1 << (d->irq - SGINT_LOCAL0));
+}
+
+static struct irq_chip ip22_local0_irq_type = {
+	.name		= "IP22 local 0",
+	.irq_mask	= disable_local0_irq,
+	.irq_unmask	= enable_local0_irq,
+};
+
+static void enable_local1_irq(struct irq_data *d)
+{
+	/* don't allow mappable interrupt to be enabled from setup_irq,
+	 * we have our own way to do so */
+	if (d->irq != SGI_MAP_1_IRQ)
+		sgint->imask1 |= (1 << (d->irq - SGINT_LOCAL1));
+}
+
+static void disable_local1_irq(struct irq_data *d)
+{
+	sgint->imask1 &= ~(1 << (d->irq - SGINT_LOCAL1));
+}
+
+static struct irq_chip ip22_local1_irq_type = {
+	.name		= "IP22 local 1",
+	.irq_mask	= disable_local1_irq,
+	.irq_unmask	= enable_local1_irq,
+};
+
+static void enable_local2_irq(struct irq_data *d)
+{
+	sgint->imask0 |= (1 << (SGI_MAP_0_IRQ - SGINT_LOCAL0));
+	sgint->cmeimask0 |= (1 << (d->irq - SGINT_LOCAL2));
+}
+
+static void disable_local2_irq(struct irq_data *d)
+{
+	sgint->cmeimask0 &= ~(1 << (d->irq - SGINT_LOCAL2));
+	if (!sgint->cmeimask0)
+		sgint->imask0 &= ~(1 << (SGI_MAP_0_IRQ - SGINT_LOCAL0));
+}
+
+static struct irq_chip ip22_local2_irq_type = {
+	.name		= "IP22 local 2",
+	.irq_mask	= disable_local2_irq,
+	.irq_unmask	= enable_local2_irq,
+};
+
+static void enable_local3_irq(struct irq_data *d)
+{
+	sgint->imask1 |= (1 << (SGI_MAP_1_IRQ - SGINT_LOCAL1));
+	sgint->cmeimask1 |= (1 << (d->irq - SGINT_LOCAL3));
+}
+
+static void disable_local3_irq(struct irq_data *d)
+{
+	sgint->cmeimask1 &= ~(1 << (d->irq - SGINT_LOCAL3));
+	if (!sgint->cmeimask1)
+		sgint->imask1 &= ~(1 << (SGI_MAP_1_IRQ - SGINT_LOCAL1));
+}
+
+static struct irq_chip ip22_local3_irq_type = {
+	.name		= "IP22 local 3",
+	.irq_mask	= disable_local3_irq,
+	.irq_unmask	= enable_local3_irq,
+};
+
+static void indy_local0_irqdispatch(void)
+{
+	u8 mask = sgint->istat0 & sgint->imask0;
+	u8 mask2;
+	int irq;
+
+	if (mask & SGINT_ISTAT0_LIO2) {
+		mask2 = sgint->vmeistat & sgint->cmeimask0;
+		irq = lc2msk_to_irqnr[mask2];
+	} else
+		irq = lc0msk_to_irqnr[mask];
+
+	/*
+	 * workaround for INT2 bug; if irq == 0, INT2 has seen a fifo full
+	 * irq, but failed to latch it into status register
+	 */
+	if (irq)
+		do_IRQ(irq);
+	else
+		do_IRQ(SGINT_LOCAL0 + 0);
+}
+
+static void indy_local1_irqdispatch(void)
+{
+	u8 mask = sgint->istat1 & sgint->imask1;
+	u8 mask2;
+	int irq;
+
+	if (mask & SGINT_ISTAT1_LIO3) {
+		mask2 = sgint->vmeistat & sgint->cmeimask1;
+		irq = lc3msk_to_irqnr[mask2];
+	} else
+		irq = lc1msk_to_irqnr[mask];
+
+	/* if irq == 0, then the interrupt has already been cleared */
+	if (irq)
+		do_IRQ(irq);
+}
+
+extern void ip22_be_interrupt(int irq);
+
+static void __irq_entry indy_buserror_irq(void)
+{
+	int irq = SGI_BUSERR_IRQ;
+
+	irq_enter();
+	kstat_incr_irq_this_cpu(irq);
+	ip22_be_interrupt(irq);
+	irq_exit();
+}
+
+static struct irqaction local0_cascade = {
+	.handler	= no_action,
+	.flags		= IRQF_NO_THREAD,
+	.name		= "local0 cascade",
+};
+
+static struct irqaction local1_cascade = {
+	.handler	= no_action,
+	.flags		= IRQF_NO_THREAD,
+	.name		= "local1 cascade",
+};
+
+static struct irqaction buserr = {
+	.handler	= no_action,
+	.flags		= IRQF_NO_THREAD,
+	.name		= "Bus Error",
+};
+
+static struct irqaction map0_cascade = {
+	.handler	= no_action,
+	.flags		= IRQF_NO_THREAD,
+	.name		= "mapable0 cascade",
+};
+
+#ifdef USE_LIO3_IRQ
+static struct irqaction map1_cascade = {
+	.handler	= no_action,
+	.flags		= IRQF_NO_THREAD,
+	.name		= "mapable1 cascade",
+};
+#define SGI_INTERRUPTS	SGINT_END
+#else
+#define SGI_INTERRUPTS	SGINT_LOCAL3
+#endif
+
+extern void indy_8254timer_irq(void);
+
+/*
+ * IRQs on the INDY look basically (barring software IRQs which we don't use
+ * at all) like:
+ *
+ *	MIPS IRQ	Source
+ *	--------	------
+ *	       0	Software (ignored)
+ *	       1	Software (ignored)
+ *	       2	Local IRQ level zero
+ *	       3	Local IRQ level one
+ *	       4	8254 Timer zero
+ *	       5	8254 Timer one
+ *	       6	Bus Error
+ *	       7	R4k timer (what we use)
+ *
+ * We handle the IRQ according to _our_ priority which is:
+ *
+ * Highest ----	    R4k Timer
+ *		    Local IRQ zero
+ *		    Local IRQ one
+ *		    Bus Error
+ *		    8254 Timer zero
+ * Lowest  ----	    8254 Timer one
+ *
+ * then we just return, if multiple IRQs are pending then we will just take
+ * another exception, big deal.
+ */
+
+asmlinkage void plat_irq_dispatch(void)
+{
+	unsigned int pending = read_c0_status() & read_c0_cause();
+
+	/*
+	 * First we check for r4k counter/timer IRQ.
+	 */
+	if (pending & CAUSEF_IP7)
+		do_IRQ(SGI_TIMER_IRQ);
+	else if (pending & CAUSEF_IP2)
+		indy_local0_irqdispatch();
+	else if (pending & CAUSEF_IP3)
+		indy_local1_irqdispatch();
+	else if (pending & CAUSEF_IP6)
+		indy_buserror_irq();
+	else if (pending & (CAUSEF_IP4 | CAUSEF_IP5))
+		indy_8254timer_irq();
+}
+
+void __init arch_init_irq(void)
+{
+	int i;
+
+	/* Init local mask --> irq tables. */
+	for (i = 0; i < 256; i++) {
+		if (i & 0x80) {
+			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 7;
+			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 7;
+			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 7;
+			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 7;
+		} else if (i & 0x40) {
+			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 6;
+			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 6;
+			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 6;
+			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 6;
+		} else if (i & 0x20) {
+			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 5;
+			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 5;
+			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 5;
+			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 5;
+		} else if (i & 0x10) {
+			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 4;
+			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 4;
+			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 4;
+			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 4;
+		} else if (i & 0x08) {
+			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 3;
+			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 3;
+			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 3;
+			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 3;
+		} else if (i & 0x04) {
+			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 2;
+			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 2;
+			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 2;
+			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 2;
+		} else if (i & 0x02) {
+			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 1;
+			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 1;
+			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 1;
+			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 1;
+		} else if (i & 0x01) {
+			lc0msk_to_irqnr[i] = SGINT_LOCAL0 + 0;
+			lc1msk_to_irqnr[i] = SGINT_LOCAL1 + 0;
+			lc2msk_to_irqnr[i] = SGINT_LOCAL2 + 0;
+			lc3msk_to_irqnr[i] = SGINT_LOCAL3 + 0;
+		} else {
+			lc0msk_to_irqnr[i] = 0;
+			lc1msk_to_irqnr[i] = 0;
+			lc2msk_to_irqnr[i] = 0;
+			lc3msk_to_irqnr[i] = 0;
+		}
+	}
+
+	/* Mask out all interrupts. */
+	sgint->imask0 = 0;
+	sgint->imask1 = 0;
+	sgint->cmeimask0 = 0;
+	sgint->cmeimask1 = 0;
+
+	/* init CPU irqs */
+	mips_cpu_irq_init();
+
+	for (i = SGINT_LOCAL0; i < SGI_INTERRUPTS; i++) {
+		struct irq_chip *handler;
+
+		if (i < SGINT_LOCAL1)
+			handler		= &ip22_local0_irq_type;
+		else if (i < SGINT_LOCAL2)
+			handler		= &ip22_local1_irq_type;
+		else if (i < SGINT_LOCAL3)
+			handler		= &ip22_local2_irq_type;
+		else
+			handler		= &ip22_local3_irq_type;
+
+		irq_set_chip_and_handler(i, handler, handle_level_irq);
+	}
+
+	/* vector handler. this register the IRQ as non-sharable */
+	setup_irq(SGI_LOCAL_0_IRQ, &local0_cascade);
+	setup_irq(SGI_LOCAL_1_IRQ, &local1_cascade);
+	setup_irq(SGI_BUSERR_IRQ, &buserr);
+
+	/* cascade in cascade. i love Indy ;-) */
+	setup_irq(SGI_MAP_0_IRQ, &map0_cascade);
+#ifdef USE_LIO3_IRQ
+	setup_irq(SGI_MAP_1_IRQ, &map1_cascade);
+#endif
+
+#ifdef CONFIG_EISA
+	if (ip22_is_fullhouse())	/* Only Indigo-2 has EISA stuff */
+		ip22_eisa_init();
+#endif
+}