/*
* 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/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/threads.h>
#include <linux/spinlock.h>
#include <linux/kernel_stat.h>
#include <asm/arch/hwregs/reg_map.h>
#include <asm/arch/hwregs/reg_rdwr.h>
#include <asm/arch/hwregs/intr_vect.h>
#include <asm/arch/hwregs/intr_vect_defs.h>
#define CPU_FIXED -1
/* IRQ masks (refer to comment for crisv32_do_multiple) */
#define TIMER_MASK (1 << (TIMER_INTR_VECT - FIRST_IRQ))
#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_IRQS] =
{[0 ... NR_IRQS - 1] = {0, CPU_MASK_ALL}};
static unsigned long irq_regs[NR_CPUS] =
{
regi_irq,
#ifdef CONFIG_SMP
regi_irq2,
#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);
/*
* Build the IRQ handler stubs using macros from irq.h. First argument is the
* IRQ number, the second argument is the corresponding bit in
* intr_rw_vect_mask found in asm/arch/hwregs/intr_vect_defs.h.
*/
BUILD_IRQ(0x31, (1 << 0)) /* memarb */
BUILD_IRQ(0x32, (1 << 1)) /* gen_io */
BUILD_IRQ(0x33, (1 << 2)) /* iop0 */
BUILD_IRQ(0x34, (1 << 3)) /* iop1 */
BUILD_IRQ(0x35, (1 << 4)) /* iop2 */
BUILD_IRQ(0x36, (1 << 5)) /* iop3 */
BUILD_IRQ(0x37, (1 << 6)) /* dma0 */
BUILD_IRQ(0x38, (1 << 7)) /* dma1 */
BUILD_IRQ(0x39, (1 << 8)) /* dma2 */
BUILD_IRQ(0x3a, (1 << 9)) /* dma3 */
BUILD_IRQ(0x3b, (1 << 10)) /* dma4 */
BUILD_IRQ(0x3c, (1 << 11)) /* dma5 */
BUILD_IRQ(0x3d, (1 << 12)) /* dma6 */
BUILD_IRQ(0x3e, (1 << 13)) /* dma7 */
BUILD_IRQ(0x3f, (1 << 14)) /* dma8 */
BUILD_IRQ(0x40, (1 << 15)) /* dma9 */
BUILD_IRQ(0x41, (1 << 16)) /* ata */
BUILD_IRQ(0x42, (1 << 17)) /* sser0 */
BUILD_IRQ(0x43, (1 << 18)) /* sser1 */
BUILD_IRQ(0x44, (1 << 19)) /* ser0 */
BUILD_IRQ(0x45, (1 << 20)) /* ser1 */
BUILD_IRQ(0x46, (1 << 21)) /* ser2 */
BUILD_IRQ(0x47, (1 << 22)) /* ser3 */
BUILD_IRQ(0x48, (1 << 23))
BUILD_IRQ(0x49, (1 << 24)) /* eth0 */
BUILD_IRQ(0x4a, (1 << 25)) /* eth1 */
BUILD_TIMER_IRQ(0x4b, (1 << 26))/* timer */
BUILD_IRQ(0x4c, (1 << 27)) /* bif_arb */
BUILD_IRQ(0x4d, (1 << 28)) /* bif_dma */
BUILD_IRQ(0x4e, (1 << 29)) /* ext */
BUILD_IRQ(0x4f, (1 << 29)) /* ipi */
/* Pointers to the low-level handlers. */
static void (*interrupt[NR_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
};
void
block_irq(int irq, int cpu)
{
int intr_mask;
unsigned long flags;
spin_lock_irqsave(&irq_lock, flags);
intr_mask = REG_RD_INT(intr_vect, irq_regs[cpu], rw_mask);
/* Remember; 1 let through, 0 block. */
intr_mask &= ~(1 << (irq - FIRST_IRQ));
REG_WR_INT(intr_vect, irq_regs[cpu], rw_mask, 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);
intr_mask = REG_RD_INT(intr_vect, irq_regs[cpu], rw_mask);
/* Remember; 1 let through, 0 block. */
intr_mask |= (1 << (irq - FIRST_IRQ));
REG_WR_INT(intr_vect, irq_regs[cpu], rw_mask, 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 (cpu_isset(cpu, irq_allocations[irq - FIRST_IRQ].mask))
goto out;
/* IRQ must be moved to another CPU. */
cpu = first_cpu(irq_allocations[irq - FIRST_IRQ].mask);
irq_allocations[irq - FIRST_IRQ].cpu = cpu;
out:
spin_unlock_irqrestore(&irq_lock, flags);
return cpu;
}
void
mask_irq(int irq)
{
int cpu;
for (cpu = 0; cpu < NR_CPUS; cpu++)
block_irq(irq, cpu);
}
void
unmask_irq(int irq)
{
unblock_irq(irq, irq_cpu(irq));
}
static unsigned int startup_crisv32_irq(unsigned int irq)
{
unmask_irq(irq);
return 0;
}
static void shutdown_crisv32_irq(unsigned int irq)
{
mask_irq(irq);
}
static void enable_crisv32_irq(unsigned int irq)
{
unmask_irq(irq);
}
static void disable_crisv32_irq(unsigned int irq)
{
mask_irq(irq);
}
static void ack_crisv32_irq(unsigned int irq)
{
}
static void end_crisv32_irq(unsigned int irq)
{
}
void set_affinity_crisv32_irq(unsigned int irq, cpumask_t dest)
{
unsigned long flags;
spin_lock_irqsave(&irq_lock, flags);
irq_allocations[irq - FIRST_IRQ].mask = dest;
spin_unlock_irqrestore(&irq_lock, flags);
}
static struct hw_interrupt_type crisv32_irq_type = {
.typename = "CRISv32",
.startup = startup_crisv32_irq,
.shutdown = shutdown_crisv32_irq,
.enable = enable_crisv32_irq,
.disable = disable_crisv32_irq,
.ack = ack_crisv32_irq,
.end = end_crisv32_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 and
* are IRQF_DISABLED 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;
int bit;
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();
/* Get which IRQs that happened. */
masked = REG_RD_INT(intr_vect, irq_regs[cpu], r_masked_vect);
/* Calculate new IRQ mask with these IRQs disabled. */
mask = REG_RD_INT(intr_vect, irq_regs[cpu], rw_mask);
mask &= ~masked;
/* Timer IRQ is never masked */
if (masked & TIMER_MASK)
mask |= TIMER_MASK;
/* Block all the IRQs */
REG_WR_INT(intr_vect, irq_regs[cpu], rw_mask, mask);
/* Check for timer IRQ and handle it special. */
if (masked & TIMER_MASK) {
masked &= ~TIMER_MASK;
do_IRQ(TIMER_INTR_VECT, regs);
}
#ifdef IGNORE_MASK
/* Remove IRQs that can't be handled as multiple. */
masked &= ~IGNORE_MASK;
#endif
/* Handle the rest of the IRQs. */
for (bit = 0; bit < 32; bit++)
{
if (masked & (1 << bit))
do_IRQ(bit + FIRST_IRQ, regs);
}
/* Unblock all the IRQs. */
mask = REG_RD_INT(intr_vect, irq_regs[cpu], rw_mask);
mask |= masked;
REG_WR_INT(intr_vect, irq_regs[cpu], rw_mask, mask);
/* This irq_exit() will trigger the soft IRQs. */
irq_exit();
}
/*
* 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};
/* Clear all interrupts masks. */
REG_WR(intr_vect, regi_irq, rw_mask, vect_mask);
for (i = 0; i < 256; i++)
etrax_irv->v[i] = weird_irq;
/* Point all IRQs to bad handlers. */
for (i = FIRST_IRQ, j = 0; j < NR_IRQS; i++, j++) {
irq_desc[j].chip = &crisv32_irq_type;
set_exception_vector(i, interrupt[j]);
}
/* Mark Timer and IPI IRQs as CPU local */
irq_allocations[TIMER_INTR_VECT - FIRST_IRQ].cpu = CPU_FIXED;
irq_desc[TIMER_INTR_VECT].status |= IRQ_PER_CPU;
irq_allocations[IPI_INTR_VECT - FIRST_IRQ].cpu = CPU_FIXED;
irq_desc[IPI_INTR_VECT].status |= 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);
/* 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
}
