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-rw-r--r--arch/mips/sibyte/bcm1480/irq.c476
1 files changed, 476 insertions, 0 deletions
diff --git a/arch/mips/sibyte/bcm1480/irq.c b/arch/mips/sibyte/bcm1480/irq.c
new file mode 100644
index 00000000000..b2a1ba5d23d
--- /dev/null
+++ b/arch/mips/sibyte/bcm1480/irq.c
@@ -0,0 +1,476 @@
+/*
+ * Copyright (C) 2000,2001,2002,2003,2004 Broadcom Corporation
+ *
+ * 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; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/kernel_stat.h>
+
+#include <asm/errno.h>
+#include <asm/signal.h>
+#include <asm/system.h>
+#include <asm/ptrace.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
+ */
+
+
+#define shutdown_bcm1480_irq disable_bcm1480_irq
+static void end_bcm1480_irq(unsigned int irq);
+static void enable_bcm1480_irq(unsigned int irq);
+static void disable_bcm1480_irq(unsigned int irq);
+static unsigned int startup_bcm1480_irq(unsigned int irq);
+static void ack_bcm1480_irq(unsigned int irq);
+#ifdef CONFIG_SMP
+static void bcm1480_set_affinity(unsigned int irq, cpumask_t mask);
+#endif
+
+#ifdef CONFIG_PCI
+extern unsigned long ht_eoi_space;
+#endif
+
+#ifdef CONFIG_KGDB
+#include <asm/gdb-stub.h>
+extern void breakpoint(void);
+static int kgdb_irq;
+#ifdef CONFIG_GDB_CONSOLE
+extern void register_gdb_console(void);
+#endif
+
+/* kgdb is on when configured. Pass "nokgdb" kernel arg to turn it off */
+static int kgdb_flag = 1;
+static int __init nokgdb(char *str)
+{
+ kgdb_flag = 0;
+ return 1;
+}
+__setup("nokgdb", nokgdb);
+
+/* Default to UART1 */
+int kgdb_port = 1;
+#ifdef CONFIG_SIBYTE_SB1250_DUART
+extern char sb1250_duart_present[];
+#endif
+#endif
+
+static struct hw_interrupt_type bcm1480_irq_type = {
+ .typename = "BCM1480-IMR",
+ .startup = startup_bcm1480_irq,
+ .shutdown = shutdown_bcm1480_irq,
+ .enable = enable_bcm1480_irq,
+ .disable = disable_bcm1480_irq,
+ .ack = ack_bcm1480_irq,
+ .end = end_bcm1480_irq,
+#ifdef CONFIG_SMP
+ .set_affinity = bcm1480_set_affinity
+#endif
+};
+
+/* Store the CPU id (not the logical number) */
+int bcm1480_irq_owner[BCM1480_NR_IRQS];
+
+DEFINE_SPINLOCK(bcm1480_imr_lock);
+
+void bcm1480_mask_irq(int cpu, int irq)
+{
+ unsigned long flags;
+ u64 cur_ints,hl_spacing;
+
+ 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));
+ spin_unlock_irqrestore(&bcm1480_imr_lock, flags);
+}
+
+void bcm1480_unmask_irq(int cpu, int irq)
+{
+ unsigned long flags;
+ u64 cur_ints,hl_spacing;
+
+ 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));
+ spin_unlock_irqrestore(&bcm1480_imr_lock, flags);
+}
+
+#ifdef CONFIG_SMP
+static void bcm1480_set_affinity(unsigned int irq, cpumask_t mask)
+{
+ int i = 0, old_cpu, cpu, int_on;
+ u64 cur_ints;
+ irq_desc_t *desc = irq_desc + irq;
+ unsigned long flags;
+ unsigned int irq_dirty;
+
+ i = first_cpu(mask);
+ if (next_cpu(i, mask) <= NR_CPUS) {
+ printk("attempted to set irq affinity for irq %d to multiple CPUs\n", irq);
+ return;
+ }
+
+ /* Convert logical CPU to physical CPU */
+ cpu = cpu_logical_map(i);
+
+ /* Protect against other affinity changers and IMR manipulation */
+ spin_lock_irqsave(&desc->lock, flags);
+ spin_lock(&bcm1480_imr_lock);
+
+ /* 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;
+ }
+
+ int k;
+ 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)));
+ }
+ }
+ spin_unlock(&bcm1480_imr_lock);
+ spin_unlock_irqrestore(&desc->lock, flags);
+}
+#endif
+
+
+/* Defined in arch/mips/sibyte/bcm1480/irq_handler.S */
+extern void bcm1480_irq_handler(void);
+
+/*****************************************************************************/
+
+static unsigned int startup_bcm1480_irq(unsigned int irq)
+{
+ bcm1480_unmask_irq(bcm1480_irq_owner[irq], irq);
+
+ return 0; /* never anything pending */
+}
+
+
+static void disable_bcm1480_irq(unsigned int irq)
+{
+ bcm1480_mask_irq(bcm1480_irq_owner[irq], irq);
+}
+
+static void enable_bcm1480_irq(unsigned int irq)
+{
+ bcm1480_unmask_irq(bcm1480_irq_owner[irq], irq);
+}
+
+
+static void ack_bcm1480_irq(unsigned int irq)
+{
+ u64 pending;
+ unsigned int irq_dirty;
+
+ /*
+ * 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;
+ }
+ int k;
+ 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 void end_bcm1480_irq(unsigned int irq)
+{
+ if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS))) {
+ bcm1480_unmask_irq(bcm1480_irq_owner[irq], irq);
+ }
+}
+
+
+void __init init_bcm1480_irqs(void)
+{
+ int i;
+
+ for (i = 0; i < NR_IRQS; i++) {
+ irq_desc[i].status = IRQ_DISABLED;
+ irq_desc[i].action = 0;
+ irq_desc[i].depth = 1;
+ if (i < BCM1480_NR_IRQS) {
+ irq_desc[i].handler = &bcm1480_irq_type;
+ bcm1480_irq_owner[i] = 0;
+ } else {
+ irq_desc[i].handler = &no_irq_type;
+ }
+ }
+}
+
+
+static irqreturn_t bcm1480_dummy_handler(int irq, void *dev_id,
+ struct pt_regs *regs)
+{
+ return IRQ_NONE;
+}
+
+static struct irqaction bcm1480_dummy_action = {
+ .handler = bcm1480_dummy_handler,
+ .flags = 0,
+ .mask = CPU_MASK_NONE,
+ .name = "bcm1480-private",
+ .next = NULL,
+ .dev_id = 0
+};
+
+int bcm1480_steal_irq(int irq)
+{
+ irq_desc_t *desc = irq_desc + irq;
+ unsigned long flags;
+ int retval = 0;
+
+ if (irq >= BCM1480_NR_IRQS)
+ return -EINVAL;
+
+ spin_lock_irqsave(&desc->lock,flags);
+ /* Don't allow sharing at all for these */
+ if (desc->action != NULL)
+ retval = -EBUSY;
+ else {
+ desc->action = &bcm1480_dummy_action;
+ desc->depth = 0;
+ }
+ spin_unlock_irqrestore(&desc->lock,flags);
+ return 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 requred 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)));
+ }
+
+ bcm1480_steal_irq(K_BCM1480_INT_MBOX_0_0);
+
+ /*
+ * 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.
+ */
+
+#ifdef CONFIG_KGDB
+ imask |= STATUSF_IP6;
+#endif
+ /* Enable necessary IPs, disable the rest */
+ change_c0_status(ST0_IM, imask);
+ set_except_vector(0, bcm1480_irq_handler);
+
+#ifdef CONFIG_KGDB
+ if (kgdb_flag) {
+ kgdb_irq = K_BCM1480_INT_UART_0 + kgdb_port;
+
+#ifdef CONFIG_SIBYTE_SB1250_DUART
+ sb1250_duart_present[kgdb_port] = 0;
+#endif
+ /* Setup uart 1 settings, mapper */
+ /* QQQ FIXME */
+ __raw_writeq(M_DUART_IMR_BRK, IO_SPACE_BASE + A_DUART_IMRREG(kgdb_port));
+
+ bcm1480_steal_irq(kgdb_irq);
+ __raw_writeq(IMR_IP6_VAL,
+ IO_SPACE_BASE + A_BCM1480_IMR_REGISTER(0, R_BCM1480_IMR_INTERRUPT_MAP_BASE_H) +
+ (kgdb_irq<<3));
+ bcm1480_unmask_irq(0, kgdb_irq);
+
+#ifdef CONFIG_GDB_CONSOLE
+ register_gdb_console();
+#endif
+ prom_printf("Waiting for GDB on UART port %d\n", kgdb_port);
+ set_debug_traps();
+ breakpoint();
+ }
+#endif
+}
+
+#ifdef CONFIG_KGDB
+
+#include <linux/delay.h>
+
+#define duart_out(reg, val) csr_out32(val, IOADDR(A_DUART_CHANREG(kgdb_port,reg)))
+#define duart_in(reg) csr_in32(IOADDR(A_DUART_CHANREG(kgdb_port,reg)))
+
+void bcm1480_kgdb_interrupt(struct pt_regs *regs)
+{
+ /*
+ * Clear break-change status (allow some time for the remote
+ * host to stop the break, since we would see another
+ * interrupt on the end-of-break too)
+ */
+ kstat.irqs[smp_processor_id()][kgdb_irq]++;
+ mdelay(500);
+ duart_out(R_DUART_CMD, V_DUART_MISC_CMD_RESET_BREAK_INT |
+ M_DUART_RX_EN | M_DUART_TX_EN);
+ set_async_breakpoint(&regs->cp0_epc);
+}
+
+#endif /* CONFIG_KGDB */