diff options
Diffstat (limited to 'arch/cris/arch-v32/kernel/irq.c')
| -rw-r--r-- | arch/cris/arch-v32/kernel/irq.c | 520 |
1 files changed, 520 insertions, 0 deletions
diff --git a/arch/cris/arch-v32/kernel/irq.c b/arch/cris/arch-v32/kernel/irq.c new file mode 100644 index 000000000..6a881e0e9 --- /dev/null +++ b/arch/cris/arch-v32/kernel/irq.c @@ -0,0 +1,520 @@ +/* + * Copyright (C) 2003, Axis Communications AB. + */ + +#include <asm/irq.h> +#include <linux/irq.h> +#include <linux/interrupt.h> +#include <linux/smp.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/profile.h> +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <linux/threads.h> +#include <linux/spinlock.h> +#include <linux/kernel_stat.h> +#include <hwregs/reg_map.h> +#include <hwregs/reg_rdwr.h> +#include <hwregs/intr_vect.h> +#include <hwregs/intr_vect_defs.h> + +#define CPU_FIXED -1 + +/* IRQ masks (refer to comment for crisv32_do_multiple) */ +#if TIMER0_INTR_VECT - FIRST_IRQ < 32 +#define TIMER_MASK (1 << (TIMER0_INTR_VECT - FIRST_IRQ)) +#undef TIMER_VECT1 +#else +#define TIMER_MASK (1 << (TIMER0_INTR_VECT - FIRST_IRQ - 32)) +#define TIMER_VECT1 +#endif +#ifdef CONFIG_ETRAX_KGDB +#if defined(CONFIG_ETRAX_KGDB_PORT0) +#define IGNOREMASK (1 << (SER0_INTR_VECT - FIRST_IRQ)) +#elif defined(CONFIG_ETRAX_KGDB_PORT1) +#define IGNOREMASK (1 << (SER1_INTR_VECT - FIRST_IRQ)) +#elif defined(CONFIG_ETRAX_KGB_PORT2) +#define IGNOREMASK (1 << (SER2_INTR_VECT - FIRST_IRQ)) +#elif defined(CONFIG_ETRAX_KGDB_PORT3) +#define IGNOREMASK (1 << (SER3_INTR_VECT - FIRST_IRQ)) +#endif +#endif + +DEFINE_SPINLOCK(irq_lock); + +struct cris_irq_allocation +{ + int cpu; /* The CPU to which the IRQ is currently allocated. */ + cpumask_t mask; /* The CPUs to which the IRQ may be allocated. */ +}; + +struct cris_irq_allocation irq_allocations[NR_REAL_IRQS] = + { [0 ... NR_REAL_IRQS - 1] = {0, CPU_MASK_ALL} }; + +static unsigned long irq_regs[NR_CPUS] = +{ + regi_irq, +}; + +#if NR_REAL_IRQS > 32 +#define NBR_REGS 2 +#else +#define NBR_REGS 1 +#endif + +unsigned long cpu_irq_counters[NR_CPUS]; +unsigned long irq_counters[NR_REAL_IRQS]; + +/* From irq.c. */ +extern void weird_irq(void); + +/* From entry.S. */ +extern void system_call(void); +extern void nmi_interrupt(void); +extern void multiple_interrupt(void); +extern void gdb_handle_exception(void); +extern void i_mmu_refill(void); +extern void i_mmu_invalid(void); +extern void i_mmu_access(void); +extern void i_mmu_execute(void); +extern void d_mmu_refill(void); +extern void d_mmu_invalid(void); +extern void d_mmu_access(void); +extern void d_mmu_write(void); + +/* From kgdb.c. */ +extern void kgdb_init(void); +extern void breakpoint(void); + +/* From traps.c. */ +extern void breakh_BUG(void); + +/* + * Build the IRQ handler stubs using macros from irq.h. + */ +#ifdef CONFIG_CRIS_MACH_ARTPEC3 +BUILD_TIMER_IRQ(0x31, 0) +#else +BUILD_IRQ(0x31) +#endif +BUILD_IRQ(0x32) +BUILD_IRQ(0x33) +BUILD_IRQ(0x34) +BUILD_IRQ(0x35) +BUILD_IRQ(0x36) +BUILD_IRQ(0x37) +BUILD_IRQ(0x38) +BUILD_IRQ(0x39) +BUILD_IRQ(0x3a) +BUILD_IRQ(0x3b) +BUILD_IRQ(0x3c) +BUILD_IRQ(0x3d) +BUILD_IRQ(0x3e) +BUILD_IRQ(0x3f) +BUILD_IRQ(0x40) +BUILD_IRQ(0x41) +BUILD_IRQ(0x42) +BUILD_IRQ(0x43) +BUILD_IRQ(0x44) +BUILD_IRQ(0x45) +BUILD_IRQ(0x46) +BUILD_IRQ(0x47) +BUILD_IRQ(0x48) +BUILD_IRQ(0x49) +BUILD_IRQ(0x4a) +#ifdef CONFIG_ETRAXFS +BUILD_TIMER_IRQ(0x4b, 0) +#else +BUILD_IRQ(0x4b) +#endif +BUILD_IRQ(0x4c) +BUILD_IRQ(0x4d) +BUILD_IRQ(0x4e) +BUILD_IRQ(0x4f) +BUILD_IRQ(0x50) +#if MACH_IRQS > 32 +BUILD_IRQ(0x51) +BUILD_IRQ(0x52) +BUILD_IRQ(0x53) +BUILD_IRQ(0x54) +BUILD_IRQ(0x55) +BUILD_IRQ(0x56) +BUILD_IRQ(0x57) +BUILD_IRQ(0x58) +BUILD_IRQ(0x59) +BUILD_IRQ(0x5a) +BUILD_IRQ(0x5b) +BUILD_IRQ(0x5c) +BUILD_IRQ(0x5d) +BUILD_IRQ(0x5e) +BUILD_IRQ(0x5f) +BUILD_IRQ(0x60) +BUILD_IRQ(0x61) +BUILD_IRQ(0x62) +BUILD_IRQ(0x63) +BUILD_IRQ(0x64) +BUILD_IRQ(0x65) +BUILD_IRQ(0x66) +BUILD_IRQ(0x67) +BUILD_IRQ(0x68) +BUILD_IRQ(0x69) +BUILD_IRQ(0x6a) +BUILD_IRQ(0x6b) +BUILD_IRQ(0x6c) +BUILD_IRQ(0x6d) +BUILD_IRQ(0x6e) +BUILD_IRQ(0x6f) +BUILD_IRQ(0x70) +#endif + +/* Pointers to the low-level handlers. */ +static void (*interrupt[MACH_IRQS])(void) = { + IRQ0x31_interrupt, IRQ0x32_interrupt, IRQ0x33_interrupt, + IRQ0x34_interrupt, IRQ0x35_interrupt, IRQ0x36_interrupt, + IRQ0x37_interrupt, IRQ0x38_interrupt, IRQ0x39_interrupt, + IRQ0x3a_interrupt, IRQ0x3b_interrupt, IRQ0x3c_interrupt, + IRQ0x3d_interrupt, IRQ0x3e_interrupt, IRQ0x3f_interrupt, + IRQ0x40_interrupt, IRQ0x41_interrupt, IRQ0x42_interrupt, + IRQ0x43_interrupt, IRQ0x44_interrupt, IRQ0x45_interrupt, + IRQ0x46_interrupt, IRQ0x47_interrupt, IRQ0x48_interrupt, + IRQ0x49_interrupt, IRQ0x4a_interrupt, IRQ0x4b_interrupt, + IRQ0x4c_interrupt, IRQ0x4d_interrupt, IRQ0x4e_interrupt, + IRQ0x4f_interrupt, IRQ0x50_interrupt, +#if MACH_IRQS > 32 + IRQ0x51_interrupt, IRQ0x52_interrupt, IRQ0x53_interrupt, + IRQ0x54_interrupt, IRQ0x55_interrupt, IRQ0x56_interrupt, + IRQ0x57_interrupt, IRQ0x58_interrupt, IRQ0x59_interrupt, + IRQ0x5a_interrupt, IRQ0x5b_interrupt, IRQ0x5c_interrupt, + IRQ0x5d_interrupt, IRQ0x5e_interrupt, IRQ0x5f_interrupt, + IRQ0x60_interrupt, IRQ0x61_interrupt, IRQ0x62_interrupt, + IRQ0x63_interrupt, IRQ0x64_interrupt, IRQ0x65_interrupt, + IRQ0x66_interrupt, IRQ0x67_interrupt, IRQ0x68_interrupt, + IRQ0x69_interrupt, IRQ0x6a_interrupt, IRQ0x6b_interrupt, + IRQ0x6c_interrupt, IRQ0x6d_interrupt, IRQ0x6e_interrupt, + IRQ0x6f_interrupt, IRQ0x70_interrupt, +#endif +}; + +void +block_irq(int irq, int cpu) +{ + int intr_mask; + unsigned long flags; + + spin_lock_irqsave(&irq_lock, flags); + /* Remember, 1 let thru, 0 block. */ + if (irq - FIRST_IRQ < 32) { + intr_mask = REG_RD_INT_VECT(intr_vect, irq_regs[cpu], + rw_mask, 0); + intr_mask &= ~(1 << (irq - FIRST_IRQ)); + REG_WR_INT_VECT(intr_vect, irq_regs[cpu], rw_mask, + 0, intr_mask); + } else { + intr_mask = REG_RD_INT_VECT(intr_vect, irq_regs[cpu], + rw_mask, 1); + intr_mask &= ~(1 << (irq - FIRST_IRQ - 32)); + REG_WR_INT_VECT(intr_vect, irq_regs[cpu], rw_mask, + 1, intr_mask); + } + spin_unlock_irqrestore(&irq_lock, flags); +} + +void +unblock_irq(int irq, int cpu) +{ + int intr_mask; + unsigned long flags; + + spin_lock_irqsave(&irq_lock, flags); + /* Remember, 1 let thru, 0 block. */ + if (irq - FIRST_IRQ < 32) { + intr_mask = REG_RD_INT_VECT(intr_vect, irq_regs[cpu], + rw_mask, 0); + intr_mask |= (1 << (irq - FIRST_IRQ)); + REG_WR_INT_VECT(intr_vect, irq_regs[cpu], rw_mask, + 0, intr_mask); + } else { + intr_mask = REG_RD_INT_VECT(intr_vect, irq_regs[cpu], + rw_mask, 1); + intr_mask |= (1 << (irq - FIRST_IRQ - 32)); + REG_WR_INT_VECT(intr_vect, irq_regs[cpu], rw_mask, + 1, intr_mask); + } + spin_unlock_irqrestore(&irq_lock, flags); +} + +/* Find out which CPU the irq should be allocated to. */ +static int irq_cpu(int irq) +{ + int cpu; + unsigned long flags; + + spin_lock_irqsave(&irq_lock, flags); + cpu = irq_allocations[irq - FIRST_IRQ].cpu; + + /* Fixed interrupts stay on the local CPU. */ + if (cpu == CPU_FIXED) + { + spin_unlock_irqrestore(&irq_lock, flags); + return smp_processor_id(); + } + + + /* Let the interrupt stay if possible */ + if (cpumask_test_cpu(cpu, &irq_allocations[irq - FIRST_IRQ].mask)) + goto out; + + /* IRQ must be moved to another CPU. */ + cpu = cpumask_first(&irq_allocations[irq - FIRST_IRQ].mask); + irq_allocations[irq - FIRST_IRQ].cpu = cpu; +out: + spin_unlock_irqrestore(&irq_lock, flags); + return cpu; +} + +void crisv32_mask_irq(int irq) +{ + int cpu; + + for (cpu = 0; cpu < NR_CPUS; cpu++) + block_irq(irq, cpu); +} + +void crisv32_unmask_irq(int irq) +{ + unblock_irq(irq, irq_cpu(irq)); +} + + +static void enable_crisv32_irq(struct irq_data *data) +{ + crisv32_unmask_irq(data->irq); +} + +static void disable_crisv32_irq(struct irq_data *data) +{ + crisv32_mask_irq(data->irq); +} + +static int set_affinity_crisv32_irq(struct irq_data *data, + const struct cpumask *dest, bool force) +{ + unsigned long flags; + + spin_lock_irqsave(&irq_lock, flags); + irq_allocations[data->irq - FIRST_IRQ].mask = *dest; + spin_unlock_irqrestore(&irq_lock, flags); + return 0; +} + +static struct irq_chip crisv32_irq_type = { + .name = "CRISv32", + .irq_shutdown = disable_crisv32_irq, + .irq_enable = enable_crisv32_irq, + .irq_disable = disable_crisv32_irq, + .irq_set_affinity = set_affinity_crisv32_irq, +}; + +void +set_exception_vector(int n, irqvectptr addr) +{ + etrax_irv->v[n] = (irqvectptr) addr; +} + +extern void do_IRQ(int irq, struct pt_regs * regs); + +void +crisv32_do_IRQ(int irq, int block, struct pt_regs* regs) +{ + /* Interrupts that may not be moved to another CPU may + * skip blocking. This is currently only valid for the + * timer IRQ and the IPI and is used for the timer + * interrupt to avoid watchdog starvation. + */ + if (!block) { + do_IRQ(irq, regs); + return; + } + + block_irq(irq, smp_processor_id()); + do_IRQ(irq, regs); + + unblock_irq(irq, irq_cpu(irq)); +} + +/* If multiple interrupts occur simultaneously we get a multiple + * interrupt from the CPU and software has to sort out which + * interrupts that happened. There are two special cases here: + * + * 1. Timer interrupts may never be blocked because of the + * watchdog (refer to comment in include/asr/arch/irq.h) + * 2. GDB serial port IRQs are unhandled here and will be handled + * as a single IRQ when it strikes again because the GDB + * stubb wants to save the registers in its own fashion. + */ +void +crisv32_do_multiple(struct pt_regs* regs) +{ + int cpu; + int mask; + int masked[NBR_REGS]; + int bit; + int i; + + cpu = smp_processor_id(); + + /* An extra irq_enter here to prevent softIRQs to run after + * each do_IRQ. This will decrease the interrupt latency. + */ + irq_enter(); + + for (i = 0; i < NBR_REGS; i++) { + /* Get which IRQs that happened. */ + masked[i] = REG_RD_INT_VECT(intr_vect, irq_regs[cpu], + r_masked_vect, i); + + /* Calculate new IRQ mask with these IRQs disabled. */ + mask = REG_RD_INT_VECT(intr_vect, irq_regs[cpu], rw_mask, i); + mask &= ~masked[i]; + + /* Timer IRQ is never masked */ +#ifdef TIMER_VECT1 + if ((i == 1) && (masked[0] & TIMER_MASK)) + mask |= TIMER_MASK; +#else + if ((i == 0) && (masked[0] & TIMER_MASK)) + mask |= TIMER_MASK; +#endif + /* Block all the IRQs */ + REG_WR_INT_VECT(intr_vect, irq_regs[cpu], rw_mask, i, mask); + + /* Check for timer IRQ and handle it special. */ +#ifdef TIMER_VECT1 + if ((i == 1) && (masked[i] & TIMER_MASK)) { + masked[i] &= ~TIMER_MASK; + do_IRQ(TIMER0_INTR_VECT, regs); + } +#else + if ((i == 0) && (masked[i] & TIMER_MASK)) { + masked[i] &= ~TIMER_MASK; + do_IRQ(TIMER0_INTR_VECT, regs); + } +#endif + } + +#ifdef IGNORE_MASK + /* Remove IRQs that can't be handled as multiple. */ + masked[0] &= ~IGNORE_MASK; +#endif + + /* Handle the rest of the IRQs. */ + for (i = 0; i < NBR_REGS; i++) { + for (bit = 0; bit < 32; bit++) { + if (masked[i] & (1 << bit)) + do_IRQ(bit + FIRST_IRQ + i*32, regs); + } + } + + /* Unblock all the IRQs. */ + for (i = 0; i < NBR_REGS; i++) { + mask = REG_RD_INT_VECT(intr_vect, irq_regs[cpu], rw_mask, i); + mask |= masked[i]; + REG_WR_INT_VECT(intr_vect, irq_regs[cpu], rw_mask, i, mask); + } + + /* This irq_exit() will trigger the soft IRQs. */ + irq_exit(); +} + +static int crisv32_irq_map(struct irq_domain *h, unsigned int virq, + irq_hw_number_t hw_irq_num) +{ + irq_set_chip_and_handler(virq, &crisv32_irq_type, handle_simple_irq); + + return 0; +} + +static struct irq_domain_ops crisv32_irq_ops = { + .map = crisv32_irq_map, + .xlate = irq_domain_xlate_onecell, +}; + +/* + * This is called by start_kernel. It fixes the IRQ masks and setup the + * interrupt vector table to point to bad_interrupt pointers. + */ +void __init +init_IRQ(void) +{ + int i; + int j; + reg_intr_vect_rw_mask vect_mask = {0}; + struct device_node *np; + struct irq_domain *domain; + + /* Clear all interrupts masks. */ + for (i = 0; i < NBR_REGS; i++) + REG_WR_VECT(intr_vect, regi_irq, rw_mask, i, vect_mask); + + for (i = 0; i < 256; i++) + etrax_irv->v[i] = weird_irq; + + np = of_find_compatible_node(NULL, NULL, "axis,crisv32-intc"); + domain = irq_domain_add_legacy(np, NR_IRQS - FIRST_IRQ, + FIRST_IRQ, FIRST_IRQ, + &crisv32_irq_ops, NULL); + BUG_ON(!domain); + irq_set_default_host(domain); + of_node_put(np); + + for (i = FIRST_IRQ, j = 0; j < NR_IRQS; i++, j++) { + set_exception_vector(i, interrupt[j]); + } + + /* Mark Timer and IPI IRQs as CPU local */ + irq_allocations[TIMER0_INTR_VECT - FIRST_IRQ].cpu = CPU_FIXED; + irq_set_status_flags(TIMER0_INTR_VECT, IRQ_PER_CPU); + irq_allocations[IPI_INTR_VECT - FIRST_IRQ].cpu = CPU_FIXED; + irq_set_status_flags(IPI_INTR_VECT, IRQ_PER_CPU); + + set_exception_vector(0x00, nmi_interrupt); + set_exception_vector(0x30, multiple_interrupt); + + /* Set up handler for various MMU bus faults. */ + set_exception_vector(0x04, i_mmu_refill); + set_exception_vector(0x05, i_mmu_invalid); + set_exception_vector(0x06, i_mmu_access); + set_exception_vector(0x07, i_mmu_execute); + set_exception_vector(0x08, d_mmu_refill); + set_exception_vector(0x09, d_mmu_invalid); + set_exception_vector(0x0a, d_mmu_access); + set_exception_vector(0x0b, d_mmu_write); + +#ifdef CONFIG_BUG + /* Break 14 handler, used to implement cheap BUG(). */ + set_exception_vector(0x1e, breakh_BUG); +#endif + + /* The system-call trap is reached by "break 13". */ + set_exception_vector(0x1d, system_call); + + /* Exception handlers for debugging, both user-mode and kernel-mode. */ + + /* Break 8. */ + set_exception_vector(0x18, gdb_handle_exception); + /* Hardware single step. */ + set_exception_vector(0x3, gdb_handle_exception); + /* Hardware breakpoint. */ + set_exception_vector(0xc, gdb_handle_exception); + +#ifdef CONFIG_ETRAX_KGDB + kgdb_init(); + /* Everything is set up; now trap the kernel. */ + breakpoint(); +#endif +} + |