| /* |
| * Copyright (C) 2000, 2001, 2002, 2003 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/kernel.h> |
| #include <linux/init.h> |
| #include <linux/linkage.h> |
| #include <linux/interrupt.h> |
| #include <linux/spinlock.h> |
| #include <linux/smp.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/time.h> |
| #include <asm/io.h> |
| |
| #include <asm/sibyte/sb1250_regs.h> |
| #include <asm/sibyte/sb1250_int.h> |
| #include <asm/sibyte/sb1250_uart.h> |
| #include <asm/sibyte/sb1250_scd.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 |
| */ |
| |
| |
| static void end_sb1250_irq(unsigned int irq); |
| static void enable_sb1250_irq(unsigned int irq); |
| static void disable_sb1250_irq(unsigned int irq); |
| static void ack_sb1250_irq(unsigned int irq); |
| #ifdef CONFIG_SMP |
| static void sb1250_set_affinity(unsigned int irq, const struct cpumask *mask); |
| #endif |
| |
| #ifdef CONFIG_SIBYTE_HAS_LDT |
| extern unsigned long ldt_eoi_space; |
| #endif |
| |
| static struct irq_chip sb1250_irq_type = { |
| .name = "SB1250-IMR", |
| .ack = ack_sb1250_irq, |
| .mask = disable_sb1250_irq, |
| .mask_ack = ack_sb1250_irq, |
| .unmask = enable_sb1250_irq, |
| .end = end_sb1250_irq, |
| #ifdef CONFIG_SMP |
| .set_affinity = sb1250_set_affinity |
| #endif |
| }; |
| |
| /* Store the CPU id (not the logical number) */ |
| int sb1250_irq_owner[SB1250_NR_IRQS]; |
| |
| DEFINE_SPINLOCK(sb1250_imr_lock); |
| |
| void sb1250_mask_irq(int cpu, int irq) |
| { |
| unsigned long flags; |
| u64 cur_ints; |
| |
| spin_lock_irqsave(&sb1250_imr_lock, flags); |
| cur_ints = ____raw_readq(IOADDR(A_IMR_MAPPER(cpu) + |
| R_IMR_INTERRUPT_MASK)); |
| cur_ints |= (((u64) 1) << irq); |
| ____raw_writeq(cur_ints, IOADDR(A_IMR_MAPPER(cpu) + |
| R_IMR_INTERRUPT_MASK)); |
| spin_unlock_irqrestore(&sb1250_imr_lock, flags); |
| } |
| |
| void sb1250_unmask_irq(int cpu, int irq) |
| { |
| unsigned long flags; |
| u64 cur_ints; |
| |
| spin_lock_irqsave(&sb1250_imr_lock, flags); |
| cur_ints = ____raw_readq(IOADDR(A_IMR_MAPPER(cpu) + |
| R_IMR_INTERRUPT_MASK)); |
| cur_ints &= ~(((u64) 1) << irq); |
| ____raw_writeq(cur_ints, IOADDR(A_IMR_MAPPER(cpu) + |
| R_IMR_INTERRUPT_MASK)); |
| spin_unlock_irqrestore(&sb1250_imr_lock, flags); |
| } |
| |
| #ifdef CONFIG_SMP |
| static void sb1250_set_affinity(unsigned int irq, const struct cpumask *mask) |
| { |
| int i = 0, old_cpu, cpu, int_on; |
| u64 cur_ints; |
| unsigned long flags; |
| |
| i = cpumask_first(mask); |
| |
| if (cpumask_weight(mask) > 1) { |
| 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(&sb1250_imr_lock, flags); |
| |
| /* Swizzle each CPU's IMR (but leave the IP selection alone) */ |
| old_cpu = sb1250_irq_owner[irq]; |
| cur_ints = ____raw_readq(IOADDR(A_IMR_MAPPER(old_cpu) + |
| R_IMR_INTERRUPT_MASK)); |
| int_on = !(cur_ints & (((u64) 1) << irq)); |
| if (int_on) { |
| /* If it was on, mask it */ |
| cur_ints |= (((u64) 1) << irq); |
| ____raw_writeq(cur_ints, IOADDR(A_IMR_MAPPER(old_cpu) + |
| R_IMR_INTERRUPT_MASK)); |
| } |
| sb1250_irq_owner[irq] = cpu; |
| if (int_on) { |
| /* unmask for the new CPU */ |
| cur_ints = ____raw_readq(IOADDR(A_IMR_MAPPER(cpu) + |
| R_IMR_INTERRUPT_MASK)); |
| cur_ints &= ~(((u64) 1) << irq); |
| ____raw_writeq(cur_ints, IOADDR(A_IMR_MAPPER(cpu) + |
| R_IMR_INTERRUPT_MASK)); |
| } |
| spin_unlock_irqrestore(&sb1250_imr_lock, flags); |
| } |
| #endif |
| |
| /*****************************************************************************/ |
| |
| static void disable_sb1250_irq(unsigned int irq) |
| { |
| sb1250_mask_irq(sb1250_irq_owner[irq], irq); |
| } |
| |
| static void enable_sb1250_irq(unsigned int irq) |
| { |
| sb1250_unmask_irq(sb1250_irq_owner[irq], irq); |
| } |
| |
| |
| static void ack_sb1250_irq(unsigned int irq) |
| { |
| #ifdef CONFIG_SIBYTE_HAS_LDT |
| u64 pending; |
| |
| /* |
| * 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) |
| */ |
| pending = __raw_readq(IOADDR(A_IMR_REGISTER(sb1250_irq_owner[irq], |
| R_IMR_LDT_INTERRUPT))); |
| pending &= ((u64)1 << (irq)); |
| if (pending) { |
| int i; |
| for (i=0; i<NR_CPUS; i++) { |
| int cpu; |
| #ifdef CONFIG_SMP |
| cpu = cpu_logical_map(i); |
| #else |
| cpu = i; |
| #endif |
| /* |
| * Clear for all CPUs so an affinity switch |
| * doesn't find an old status |
| */ |
| __raw_writeq(pending, |
| IOADDR(A_IMR_REGISTER(cpu, |
| R_IMR_LDT_INTERRUPT_CLR))); |
| } |
| |
| /* |
| * 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. |
| */ |
| *(uint32_t *)(ldt_eoi_space+(irq<<16)+(7<<2)) = 0; |
| } |
| #endif |
| sb1250_mask_irq(sb1250_irq_owner[irq], irq); |
| } |
| |
| |
| static void end_sb1250_irq(unsigned int irq) |
| { |
| if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS))) { |
| sb1250_unmask_irq(sb1250_irq_owner[irq], irq); |
| } |
| } |
| |
| |
| void __init init_sb1250_irqs(void) |
| { |
| int i; |
| |
| for (i = 0; i < SB1250_NR_IRQS; i++) { |
| set_irq_chip_and_handler(i, &sb1250_irq_type, handle_level_irq); |
| sb1250_irq_owner[i] = 0; |
| } |
| } |
| |
| |
| /* |
| * arch_init_irq is called early in the boot sequence from init/main.c via |
| * init_IRQ. 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_INT_MAP_I0 |
| #define IMR_IP3_VAL K_INT_MAP_I1 |
| #define IMR_IP4_VAL K_INT_MAP_I2 |
| #define IMR_IP5_VAL K_INT_MAP_I3 |
| #define IMR_IP6_VAL K_INT_MAP_I4 |
| |
| void __init arch_init_irq(void) |
| { |
| |
| unsigned int i; |
| u64 tmp; |
| unsigned int imask = STATUSF_IP4 | STATUSF_IP3 | STATUSF_IP2 | |
| STATUSF_IP1 | STATUSF_IP0; |
| |
| /* Default everything to IP2 */ |
| for (i = 0; i < SB1250_NR_IRQS; i++) { /* was I0 */ |
| __raw_writeq(IMR_IP2_VAL, |
| IOADDR(A_IMR_REGISTER(0, |
| R_IMR_INTERRUPT_MAP_BASE) + |
| (i << 3))); |
| __raw_writeq(IMR_IP2_VAL, |
| IOADDR(A_IMR_REGISTER(1, |
| R_IMR_INTERRUPT_MAP_BASE) + |
| (i << 3))); |
| } |
| |
| init_sb1250_irqs(); |
| |
| /* |
| * Map the high 16 bits of the mailbox registers to IP[3], for |
| * inter-cpu messages |
| */ |
| /* Was I1 */ |
| __raw_writeq(IMR_IP3_VAL, |
| IOADDR(A_IMR_REGISTER(0, R_IMR_INTERRUPT_MAP_BASE) + |
| (K_INT_MBOX_0 << 3))); |
| __raw_writeq(IMR_IP3_VAL, |
| IOADDR(A_IMR_REGISTER(1, R_IMR_INTERRUPT_MAP_BASE) + |
| (K_INT_MBOX_0 << 3))); |
| |
| /* Clear the mailboxes. The firmware may leave them dirty */ |
| __raw_writeq(0xffffffffffffffffULL, |
| IOADDR(A_IMR_REGISTER(0, R_IMR_MAILBOX_CLR_CPU))); |
| __raw_writeq(0xffffffffffffffffULL, |
| IOADDR(A_IMR_REGISTER(1, R_IMR_MAILBOX_CLR_CPU))); |
| |
| /* Mask everything except the mailbox registers for both cpus */ |
| tmp = ~((u64) 0) ^ (((u64) 1) << K_INT_MBOX_0); |
| __raw_writeq(tmp, IOADDR(A_IMR_REGISTER(0, R_IMR_INTERRUPT_MASK))); |
| __raw_writeq(tmp, IOADDR(A_IMR_REGISTER(1, R_IMR_INTERRUPT_MASK))); |
| |
| /* |
| * Note that the timer interrupts are also mapped, but this is |
| * done in sb1250_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 sb1250_mailbox_interrupt(void); |
| |
| static inline void dispatch_ip2(void) |
| { |
| unsigned int cpu = smp_processor_id(); |
| unsigned long long mask; |
| |
| /* |
| * Default...we've hit an IP[2] interrupt, which means we've got to |
| * check the 1250 interrupt registers to figure out what to do. Need |
| * to detect which CPU we're on, now that smp_affinity is supported. |
| */ |
| mask = __raw_readq(IOADDR(A_IMR_REGISTER(cpu, |
| R_IMR_INTERRUPT_STATUS_BASE))); |
| if (mask) |
| do_IRQ(fls64(mask) - 1); |
| } |
| |
| asmlinkage void plat_irq_dispatch(void) |
| { |
| unsigned int cpu = smp_processor_id(); |
| unsigned int pending; |
| |
| /* |
| * What a pain. We have to be really careful saving the upper 32 bits |
| * of any * register across function calls if we don't want them |
| * trashed--since were running in -o32, the calling routing never saves |
| * the full 64 bits of a register across a function call. Being the |
| * interrupt handler, we're guaranteed that interrupts are disabled |
| * during this code so we don't have to worry about random interrupts |
| * blasting the high 32 bits. |
| */ |
| |
| pending = read_c0_cause() & read_c0_status() & ST0_IM; |
| |
| if (pending & CAUSEF_IP7) /* CPU performance counter interrupt */ |
| do_IRQ(MIPS_CPU_IRQ_BASE + 7); |
| else if (pending & CAUSEF_IP4) |
| do_IRQ(K_INT_TIMER_0 + cpu); /* sb1250_timer_interrupt() */ |
| |
| #ifdef CONFIG_SMP |
| else if (pending & CAUSEF_IP3) |
| sb1250_mailbox_interrupt(); |
| #endif |
| |
| else if (pending & CAUSEF_IP2) |
| dispatch_ip2(); |
| else |
| spurious_interrupt(); |
| } |