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-rw-r--r--arch/mips/sibyte/bcm1480/irq.c348
1 files changed, 348 insertions, 0 deletions
diff --git a/arch/mips/sibyte/bcm1480/irq.c b/arch/mips/sibyte/bcm1480/irq.c
new file mode 100644
index 000000000..7929bee91
--- /dev/null
+++ b/arch/mips/sibyte/bcm1480/irq.c
@@ -0,0 +1,348 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2000,2001,2002,2003,2004 Broadcom Corporation
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <linux/interrupt.h>
+#include <linux/smp.h>
+#include <linux/spinlock.h>
+#include <linux/mm.h>
+#include <linux/kernel_stat.h>
+
+#include <asm/errno.h>
+#include <asm/irq_regs.h>
+#include <asm/signal.h>
+#include <asm/io.h>
+
+#include <asm/sibyte/bcm1480_regs.h>
+#include <asm/sibyte/bcm1480_int.h>
+#include <asm/sibyte/bcm1480_scd.h>
+
+#include <asm/sibyte/sb1250_uart.h>
+#include <asm/sibyte/sb1250.h>
+
+/*
+ * These are the routines that handle all the low level interrupt stuff.
+ * Actions handled here are: initialization of the interrupt map, requesting of
+ * interrupt lines by handlers, dispatching if interrupts to handlers, probing
+ * for interrupt lines
+ */
+
+#ifdef CONFIG_PCI
+extern unsigned long ht_eoi_space;
+#endif
+
+/* Store the CPU id (not the logical number) */
+int bcm1480_irq_owner[BCM1480_NR_IRQS];
+
+static DEFINE_RAW_SPINLOCK(bcm1480_imr_lock);
+
+void bcm1480_mask_irq(int cpu, int irq)
+{
+ unsigned long flags, hl_spacing;
+ u64 cur_ints;
+
+ raw_spin_lock_irqsave(&bcm1480_imr_lock, flags);
+ hl_spacing = 0;
+ if ((irq >= BCM1480_NR_IRQS_HALF) && (irq <= BCM1480_NR_IRQS)) {
+ hl_spacing = BCM1480_IMR_HL_SPACING;
+ irq -= BCM1480_NR_IRQS_HALF;
+ }
+ cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing));
+ cur_ints |= (((u64) 1) << irq);
+ ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing));
+ raw_spin_unlock_irqrestore(&bcm1480_imr_lock, flags);
+}
+
+void bcm1480_unmask_irq(int cpu, int irq)
+{
+ unsigned long flags, hl_spacing;
+ u64 cur_ints;
+
+ raw_spin_lock_irqsave(&bcm1480_imr_lock, flags);
+ hl_spacing = 0;
+ if ((irq >= BCM1480_NR_IRQS_HALF) && (irq <= BCM1480_NR_IRQS)) {
+ hl_spacing = BCM1480_IMR_HL_SPACING;
+ irq -= BCM1480_NR_IRQS_HALF;
+ }
+ cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing));
+ cur_ints &= ~(((u64) 1) << irq);
+ ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing));
+ raw_spin_unlock_irqrestore(&bcm1480_imr_lock, flags);
+}
+
+#ifdef CONFIG_SMP
+static int bcm1480_set_affinity(struct irq_data *d, const struct cpumask *mask,
+ bool force)
+{
+ unsigned int irq_dirty, irq = d->irq;
+ int i = 0, old_cpu, cpu, int_on, k;
+ u64 cur_ints;
+ unsigned long flags;
+
+ i = cpumask_first_and(mask, cpu_online_mask);
+
+ /* Convert logical CPU to physical CPU */
+ cpu = cpu_logical_map(i);
+
+ /* Protect against other affinity changers and IMR manipulation */
+ raw_spin_lock_irqsave(&bcm1480_imr_lock, flags);
+
+ /* Swizzle each CPU's IMR (but leave the IP selection alone) */
+ old_cpu = bcm1480_irq_owner[irq];
+ irq_dirty = irq;
+ if ((irq_dirty >= BCM1480_NR_IRQS_HALF) && (irq_dirty <= BCM1480_NR_IRQS)) {
+ irq_dirty -= BCM1480_NR_IRQS_HALF;
+ }
+
+ for (k=0; k<2; k++) { /* Loop through high and low interrupt mask register */
+ cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(old_cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING)));
+ int_on = !(cur_ints & (((u64) 1) << irq_dirty));
+ if (int_on) {
+ /* If it was on, mask it */
+ cur_ints |= (((u64) 1) << irq_dirty);
+ ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(old_cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING)));
+ }
+ bcm1480_irq_owner[irq] = cpu;
+ if (int_on) {
+ /* unmask for the new CPU */
+ cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING)));
+ cur_ints &= ~(((u64) 1) << irq_dirty);
+ ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING)));
+ }
+ }
+ raw_spin_unlock_irqrestore(&bcm1480_imr_lock, flags);
+
+ return 0;
+}
+#endif
+
+
+/*****************************************************************************/
+
+static void disable_bcm1480_irq(struct irq_data *d)
+{
+ unsigned int irq = d->irq;
+
+ bcm1480_mask_irq(bcm1480_irq_owner[irq], irq);
+}
+
+static void enable_bcm1480_irq(struct irq_data *d)
+{
+ unsigned int irq = d->irq;
+
+ bcm1480_unmask_irq(bcm1480_irq_owner[irq], irq);
+}
+
+
+static void ack_bcm1480_irq(struct irq_data *d)
+{
+ unsigned int irq_dirty, irq = d->irq;
+ u64 pending;
+ int k;
+
+ /*
+ * If the interrupt was an HT interrupt, now is the time to
+ * clear it. NOTE: we assume the HT bridge was set up to
+ * deliver the interrupts to all CPUs (which makes affinity
+ * changing easier for us)
+ */
+ irq_dirty = irq;
+ if ((irq_dirty >= BCM1480_NR_IRQS_HALF) && (irq_dirty <= BCM1480_NR_IRQS)) {
+ irq_dirty -= BCM1480_NR_IRQS_HALF;
+ }
+ for (k=0; k<2; k++) { /* Loop through high and low LDT interrupts */
+ pending = __raw_readq(IOADDR(A_BCM1480_IMR_REGISTER(bcm1480_irq_owner[irq],
+ R_BCM1480_IMR_LDT_INTERRUPT_H + (k*BCM1480_IMR_HL_SPACING))));
+ pending &= ((u64)1 << (irq_dirty));
+ if (pending) {
+#ifdef CONFIG_SMP
+ int i;
+ for (i=0; i<NR_CPUS; i++) {
+ /*
+ * Clear for all CPUs so an affinity switch
+ * doesn't find an old status
+ */
+ __raw_writeq(pending, IOADDR(A_BCM1480_IMR_REGISTER(cpu_logical_map(i),
+ R_BCM1480_IMR_LDT_INTERRUPT_CLR_H + (k*BCM1480_IMR_HL_SPACING))));
+ }
+#else
+ __raw_writeq(pending, IOADDR(A_BCM1480_IMR_REGISTER(0, R_BCM1480_IMR_LDT_INTERRUPT_CLR_H + (k*BCM1480_IMR_HL_SPACING))));
+#endif
+
+ /*
+ * Generate EOI. For Pass 1 parts, EOI is a nop. For
+ * Pass 2, the LDT world may be edge-triggered, but
+ * this EOI shouldn't hurt. If they are
+ * level-sensitive, the EOI is required.
+ */
+#ifdef CONFIG_PCI
+ if (ht_eoi_space)
+ *(uint32_t *)(ht_eoi_space+(irq<<16)+(7<<2)) = 0;
+#endif
+ }
+ }
+ bcm1480_mask_irq(bcm1480_irq_owner[irq], irq);
+}
+
+static struct irq_chip bcm1480_irq_type = {
+ .name = "BCM1480-IMR",
+ .irq_mask_ack = ack_bcm1480_irq,
+ .irq_mask = disable_bcm1480_irq,
+ .irq_unmask = enable_bcm1480_irq,
+#ifdef CONFIG_SMP
+ .irq_set_affinity = bcm1480_set_affinity
+#endif
+};
+
+void __init init_bcm1480_irqs(void)
+{
+ int i;
+
+ for (i = 0; i < BCM1480_NR_IRQS; i++) {
+ irq_set_chip_and_handler(i, &bcm1480_irq_type,
+ handle_level_irq);
+ bcm1480_irq_owner[i] = 0;
+ }
+}
+
+/*
+ * init_IRQ is called early in the boot sequence from init/main.c. It
+ * is responsible for setting up the interrupt mapper and installing the
+ * handler that will be responsible for dispatching interrupts to the
+ * "right" place.
+ */
+/*
+ * For now, map all interrupts to IP[2]. We could save
+ * some cycles by parceling out system interrupts to different
+ * IP lines, but keep it simple for bringup. We'll also direct
+ * all interrupts to a single CPU; we should probably route
+ * PCI and LDT to one cpu and everything else to the other
+ * to balance the load a bit.
+ *
+ * On the second cpu, everything is set to IP5, which is
+ * ignored, EXCEPT the mailbox interrupt. That one is
+ * set to IP[2] so it is handled. This is needed so we
+ * can do cross-cpu function calls, as required by SMP
+ */
+
+#define IMR_IP2_VAL K_BCM1480_INT_MAP_I0
+#define IMR_IP3_VAL K_BCM1480_INT_MAP_I1
+#define IMR_IP4_VAL K_BCM1480_INT_MAP_I2
+#define IMR_IP5_VAL K_BCM1480_INT_MAP_I3
+#define IMR_IP6_VAL K_BCM1480_INT_MAP_I4
+
+void __init arch_init_irq(void)
+{
+ unsigned int i, cpu;
+ u64 tmp;
+ unsigned int imask = STATUSF_IP4 | STATUSF_IP3 | STATUSF_IP2 |
+ STATUSF_IP1 | STATUSF_IP0;
+
+ /* Default everything to IP2 */
+ /* Start with _high registers which has no bit 0 interrupt source */
+ for (i = 1; i < BCM1480_NR_IRQS_HALF; i++) { /* was I0 */
+ for (cpu = 0; cpu < 4; cpu++) {
+ __raw_writeq(IMR_IP2_VAL,
+ IOADDR(A_BCM1480_IMR_REGISTER(cpu,
+ R_BCM1480_IMR_INTERRUPT_MAP_BASE_H) + (i << 3)));
+ }
+ }
+
+ /* Now do _low registers */
+ for (i = 0; i < BCM1480_NR_IRQS_HALF; i++) {
+ for (cpu = 0; cpu < 4; cpu++) {
+ __raw_writeq(IMR_IP2_VAL,
+ IOADDR(A_BCM1480_IMR_REGISTER(cpu,
+ R_BCM1480_IMR_INTERRUPT_MAP_BASE_L) + (i << 3)));
+ }
+ }
+
+ init_bcm1480_irqs();
+
+ /*
+ * Map the high 16 bits of mailbox_0 registers to IP[3], for
+ * inter-cpu messages
+ */
+ /* Was I1 */
+ for (cpu = 0; cpu < 4; cpu++) {
+ __raw_writeq(IMR_IP3_VAL, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MAP_BASE_H) +
+ (K_BCM1480_INT_MBOX_0_0 << 3)));
+ }
+
+
+ /* Clear the mailboxes. The firmware may leave them dirty */
+ for (cpu = 0; cpu < 4; cpu++) {
+ __raw_writeq(0xffffffffffffffffULL,
+ IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_MAILBOX_0_CLR_CPU)));
+ __raw_writeq(0xffffffffffffffffULL,
+ IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_MAILBOX_1_CLR_CPU)));
+ }
+
+
+ /* Mask everything except the high 16 bit of mailbox_0 registers for all cpus */
+ tmp = ~((u64) 0) ^ ( (((u64) 1) << K_BCM1480_INT_MBOX_0_0));
+ for (cpu = 0; cpu < 4; cpu++) {
+ __raw_writeq(tmp, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MASK_H)));
+ }
+ tmp = ~((u64) 0);
+ for (cpu = 0; cpu < 4; cpu++) {
+ __raw_writeq(tmp, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MASK_L)));
+ }
+
+ /*
+ * Note that the timer interrupts are also mapped, but this is
+ * done in bcm1480_time_init(). Also, the profiling driver
+ * does its own management of IP7.
+ */
+
+ /* Enable necessary IPs, disable the rest */
+ change_c0_status(ST0_IM, imask);
+}
+
+extern void bcm1480_mailbox_interrupt(void);
+
+static inline void dispatch_ip2(void)
+{
+ unsigned long long mask_h, mask_l;
+ unsigned int cpu = smp_processor_id();
+ unsigned long base;
+
+ /*
+ * Default...we've hit an IP[2] interrupt, which means we've got to
+ * check the 1480 interrupt registers to figure out what to do. Need
+ * to detect which CPU we're on, now that smp_affinity is supported.
+ */
+ base = A_BCM1480_IMR_MAPPER(cpu);
+ mask_h = __raw_readq(
+ IOADDR(base + R_BCM1480_IMR_INTERRUPT_STATUS_BASE_H));
+ mask_l = __raw_readq(
+ IOADDR(base + R_BCM1480_IMR_INTERRUPT_STATUS_BASE_L));
+
+ if (mask_h) {
+ if (mask_h ^ 1)
+ do_IRQ(fls64(mask_h) - 1);
+ else if (mask_l)
+ do_IRQ(63 + fls64(mask_l));
+ }
+}
+
+asmlinkage void plat_irq_dispatch(void)
+{
+ unsigned int cpu = smp_processor_id();
+ unsigned int pending;
+
+ pending = read_c0_cause() & read_c0_status();
+
+ if (pending & CAUSEF_IP4)
+ do_IRQ(K_BCM1480_INT_TIMER_0 + cpu);
+#ifdef CONFIG_SMP
+ else if (pending & CAUSEF_IP3)
+ bcm1480_mailbox_interrupt();
+#endif
+
+ else if (pending & CAUSEF_IP2)
+ dispatch_ip2();
+}