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-rw-r--r--arch/mips/sgi-ip22/ip22-int.c320
1 files changed, 320 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..96798a4ab
--- /dev/null
+++ b/arch/mips/sgi-ip22/ip22-int.c
@@ -0,0 +1,320 @@
+// 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();
+}
+
+#ifdef USE_LIO3_IRQ
+#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 */
+ if (request_irq(SGI_LOCAL_0_IRQ, no_action, IRQF_NO_THREAD,
+ "local0 cascade", NULL))
+ pr_err("Failed to register local0 cascade interrupt\n");
+ if (request_irq(SGI_LOCAL_1_IRQ, no_action, IRQF_NO_THREAD,
+ "local1 cascade", NULL))
+ pr_err("Failed to register local1 cascade interrupt\n");
+ if (request_irq(SGI_BUSERR_IRQ, no_action, IRQF_NO_THREAD,
+ "Bus Error", NULL))
+ pr_err("Failed to register Bus Error interrupt\n");
+
+ /* cascade in cascade. i love Indy ;-) */
+ if (request_irq(SGI_MAP_0_IRQ, no_action, IRQF_NO_THREAD,
+ "mapable0 cascade", NULL))
+ pr_err("Failed to register mapable0 cascade interrupt\n");
+#ifdef USE_LIO3_IRQ
+ if (request_irq(SGI_MAP_1_IRQ, no_action, IRQF_NO_THREAD,
+ "mapable1 cascade", NULL))
+ pr_err("Failed to register mapable1 cascade interrupt\n");
+#endif
+
+#ifdef CONFIG_EISA
+ if (ip22_is_fullhouse()) /* Only Indigo-2 has EISA stuff */
+ ip22_eisa_init();
+#endif
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-16 10:02:40 +0000