diff options
Diffstat (limited to 'arch/cris/arch-v10/kernel/irq.c')
| -rw-r--r-- | arch/cris/arch-v10/kernel/irq.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/arch/cris/arch-v10/kernel/irq.c b/arch/cris/arch-v10/kernel/irq.c new file mode 100644 index 000000000..09cae80a8 --- /dev/null +++ b/arch/cris/arch-v10/kernel/irq.c @@ -0,0 +1,235 @@ +/* + * linux/arch/cris/kernel/irq.c + * + * Copyright (c) 2000-2002 Axis Communications AB + * + * Authors: Bjorn Wesen (bjornw@axis.com) + * + * This file contains the interrupt vectors and some + * helper functions + * + */ + +#include <asm/irq.h> +#include <asm/current.h> +#include <linux/irq.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/init.h> + +#define crisv10_mask_irq(irq_nr) (*R_VECT_MASK_CLR = 1 << (irq_nr)); +#define crisv10_unmask_irq(irq_nr) (*R_VECT_MASK_SET = 1 << (irq_nr)); + +extern void kgdb_init(void); +extern void breakpoint(void); + +/* don't use set_int_vector, it bypasses the linux interrupt handlers. it is + * global just so that the kernel gdb can use it. + */ + +void +set_int_vector(int n, irqvectptr addr) +{ + etrax_irv->v[n + 0x20] = (irqvectptr)addr; +} + +/* the breakpoint vector is obviously not made just like the normal irq handlers + * but needs to contain _code_ to jump to addr. + * + * the BREAK n instruction jumps to IBR + n * 8 + */ + +void +set_break_vector(int n, irqvectptr addr) +{ + unsigned short *jinstr = (unsigned short *)&etrax_irv->v[n*2]; + unsigned long *jaddr = (unsigned long *)(jinstr + 1); + + /* if you don't know what this does, do not touch it! */ + + *jinstr = 0x0d3f; + *jaddr = (unsigned long)addr; + + /* 00000026 <clrlop+1a> 3f0d82000000 jump 0x82 */ +} + +/* + * This builds up the IRQ handler stubs using some ugly macros in irq.h + * + * These macros create the low-level assembly IRQ routines that do all + * the operations that are needed. They are also written to be fast - and to + * disable interrupts as little as humanly possible. + * + */ + +/* IRQ0 and 1 are special traps */ +void hwbreakpoint(void); +void IRQ1_interrupt(void); +BUILD_TIMER_IRQ(2, 0x04) /* the timer interrupt is somewhat special */ +BUILD_IRQ(3, 0x08) +BUILD_IRQ(4, 0x10) +BUILD_IRQ(5, 0x20) +BUILD_IRQ(6, 0x40) +BUILD_IRQ(7, 0x80) +BUILD_IRQ(8, 0x100) +BUILD_IRQ(9, 0x200) +BUILD_IRQ(10, 0x400) +BUILD_IRQ(11, 0x800) +BUILD_IRQ(12, 0x1000) +BUILD_IRQ(13, 0x2000) +void mmu_bus_fault(void); /* IRQ 14 is the bus fault interrupt */ +void multiple_interrupt(void); /* IRQ 15 is the multiple IRQ interrupt */ +BUILD_IRQ(16, 0x10000 | 0x20000) /* ethernet tx interrupt needs to block rx */ +BUILD_IRQ(17, 0x20000 | 0x10000) /* ...and vice versa */ +BUILD_IRQ(18, 0x40000) +BUILD_IRQ(19, 0x80000) +BUILD_IRQ(20, 0x100000) +BUILD_IRQ(21, 0x200000) +BUILD_IRQ(22, 0x400000) +BUILD_IRQ(23, 0x800000) +BUILD_IRQ(24, 0x1000000) +BUILD_IRQ(25, 0x2000000) +/* IRQ 26-30 are reserved */ +BUILD_IRQ(31, 0x80000000) + +/* + * Pointers to the low-level handlers + */ + +static void (*interrupt[NR_IRQS])(void) = { + NULL, NULL, IRQ2_interrupt, IRQ3_interrupt, + IRQ4_interrupt, IRQ5_interrupt, IRQ6_interrupt, IRQ7_interrupt, + IRQ8_interrupt, IRQ9_interrupt, IRQ10_interrupt, IRQ11_interrupt, + IRQ12_interrupt, IRQ13_interrupt, NULL, NULL, + IRQ16_interrupt, IRQ17_interrupt, IRQ18_interrupt, IRQ19_interrupt, + IRQ20_interrupt, IRQ21_interrupt, IRQ22_interrupt, IRQ23_interrupt, + IRQ24_interrupt, IRQ25_interrupt, NULL, NULL, NULL, NULL, NULL, + IRQ31_interrupt +}; + +static void enable_crisv10_irq(struct irq_data *data) +{ + crisv10_unmask_irq(data->irq); +} + +static void disable_crisv10_irq(struct irq_data *data) +{ + crisv10_mask_irq(data->irq); +} + +static struct irq_chip crisv10_irq_type = { + .name = "CRISv10", + .irq_shutdown = disable_crisv10_irq, + .irq_enable = enable_crisv10_irq, + .irq_disable = disable_crisv10_irq, +}; + +void weird_irq(void); +void system_call(void); /* from entry.S */ +void do_sigtrap(void); /* from entry.S */ +void gdb_handle_breakpoint(void); /* from entry.S */ + +extern void do_IRQ(int irq, struct pt_regs * regs); + +/* Handle multiple IRQs */ +void do_multiple_IRQ(struct pt_regs* regs) +{ + int bit; + unsigned masked; + unsigned mask; + unsigned ethmask = 0; + + /* Get interrupts to mask and handle */ + mask = masked = *R_VECT_MASK_RD; + + /* Never mask timer IRQ */ + mask &= ~(IO_MASK(R_VECT_MASK_RD, timer0)); + + /* + * If either ethernet interrupt (rx or tx) is active then block + * the other one too. Unblock afterwards also. + */ + if (mask & + (IO_STATE(R_VECT_MASK_RD, dma0, active) | + IO_STATE(R_VECT_MASK_RD, dma1, active))) { + ethmask = (IO_MASK(R_VECT_MASK_RD, dma0) | + IO_MASK(R_VECT_MASK_RD, dma1)); + } + + /* Block them */ + *R_VECT_MASK_CLR = (mask | ethmask); + + /* An extra irq_enter here to prevent softIRQs to run after + * each do_IRQ. This will decrease the interrupt latency. + */ + irq_enter(); + + /* Handle all IRQs */ + for (bit = 2; bit < 32; bit++) { + if (masked & (1 << bit)) { + do_IRQ(bit, regs); + } + } + + /* This irq_exit() will trigger the soft IRQs. */ + irq_exit(); + + /* Unblock the IRQs again */ + *R_VECT_MASK_SET = (masked | ethmask); +} + +/* init_IRQ() is called by start_kernel and is responsible for fixing IRQ masks and + setting the irq vector table. +*/ + +void __init init_IRQ(void) +{ + int i; + + /* clear all interrupt masks */ + *R_IRQ_MASK0_CLR = 0xffffffff; + *R_IRQ_MASK1_CLR = 0xffffffff; + *R_IRQ_MASK2_CLR = 0xffffffff; + *R_VECT_MASK_CLR = 0xffffffff; + + for (i = 0; i < 256; i++) + etrax_irv->v[i] = weird_irq; + + /* Initialize IRQ handler descriptors. */ + for(i = 2; i < NR_IRQS; i++) { + irq_set_chip_and_handler(i, &crisv10_irq_type, + handle_simple_irq); + set_int_vector(i, interrupt[i]); + } + + /* the entries in the break vector contain actual code to be + executed by the associated break handler, rather than just a jump + address. therefore we need to setup a default breakpoint handler + for all breakpoints */ + for (i = 0; i < 16; i++) + set_break_vector(i, do_sigtrap); + + /* except IRQ 15 which is the multiple-IRQ handler on Etrax100 */ + set_int_vector(15, multiple_interrupt); + + /* 0 and 1 which are special breakpoint/NMI traps */ + set_int_vector(0, hwbreakpoint); + set_int_vector(1, IRQ1_interrupt); + + /* and irq 14 which is the mmu bus fault handler */ + set_int_vector(14, mmu_bus_fault); + + /* setup the system-call trap, which is reached by BREAK 13 */ + set_break_vector(13, system_call); + + /* setup a breakpoint handler for debugging used for both user and + kernel mode debugging (which is why it is not inside an ifdef + CONFIG_ETRAX_KGDB) */ + set_break_vector(8, gdb_handle_breakpoint); + +#ifdef CONFIG_ETRAX_KGDB + /* setup kgdb if its enabled, and break into the debugger */ + kgdb_init(); + breakpoint(); +#endif +} |