diff options
Diffstat (limited to 'arch/mips/vr4181/common/int_handler.S')
| -rw-r--r-- | arch/mips/vr4181/common/int_handler.S | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/arch/mips/vr4181/common/int_handler.S b/arch/mips/vr4181/common/int_handler.S new file mode 100644 index 00000000000..2c041b8ee52 --- /dev/null +++ b/arch/mips/vr4181/common/int_handler.S @@ -0,0 +1,206 @@ +/* + * arch/mips/vr4181/common/int_handler.S + * + * Adapted to the VR4181 and almost entirely rewritten: + * Copyright (C) 1999 Bradley D. LaRonde and Michael Klar + * + * Clean up to conform to the new IRQ + * Copyright (C) 2001 MontaVista Software Inc. + * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + */ + +#include <asm/asm.h> +#include <asm/regdef.h> +#include <asm/mipsregs.h> +#include <asm/stackframe.h> + +#include <asm/vr4181/vr4181.h> + +/* + * [jsun] + * See include/asm/vr4181/irq.h for IRQ assignment and strategy. + */ + + .text + .set noreorder + + .align 5 + NESTED(vr4181_handle_irq, PT_SIZE, ra) + + .set noat + SAVE_ALL + CLI + + .set at + .set noreorder + + mfc0 t0, CP0_CAUSE + mfc0 t2, CP0_STATUS + + and t0, t2 + + /* we check IP3 first; it happens most frequently */ + andi t1, t0, STATUSF_IP3 + bnez t1, ll_cpu_ip3 + andi t1, t0, STATUSF_IP2 + bnez t1, ll_cpu_ip2 + andi t1, t0, STATUSF_IP7 /* cpu timer */ + bnez t1, ll_cputimer_irq + andi t1, t0, STATUSF_IP4 + bnez t1, ll_cpu_ip4 + andi t1, t0, STATUSF_IP5 + bnez t1, ll_cpu_ip5 + andi t1, t0, STATUSF_IP6 + bnez t1, ll_cpu_ip6 + andi t1, t0, STATUSF_IP0 /* software int 0 */ + bnez t1, ll_cpu_ip0 + andi t1, t0, STATUSF_IP1 /* software int 1 */ + bnez t1, ll_cpu_ip1 + nop + + .set reorder +do_spurious: + j spurious_interrupt + +/* + * regular CPU irqs + */ +ll_cputimer_irq: + li a0, VR4181_IRQ_TIMER + move a1, sp + jal do_IRQ + j ret_from_irq + + +ll_cpu_ip0: + li a0, VR4181_IRQ_SW1 + move a1, sp + jal do_IRQ + j ret_from_irq + +ll_cpu_ip1: + li a0, VR4181_IRQ_SW2 + move a1, sp + jal do_IRQ + j ret_from_irq + +ll_cpu_ip3: + li a0, VR4181_IRQ_INT1 + move a1, sp + jal do_IRQ + j ret_from_irq + +ll_cpu_ip4: + li a0, VR4181_IRQ_INT2 + move a1, sp + jal do_IRQ + j ret_from_irq + +ll_cpu_ip5: + li a0, VR4181_IRQ_INT3 + move a1, sp + jal do_IRQ + j ret_from_irq + +ll_cpu_ip6: + li a0, VR4181_IRQ_INT4 + move a1, sp + jal do_IRQ + j ret_from_irq + +/* + * One of the sys irq has happend. + * + * In the interest of speed, we first determine in the following order + * which 16-irq block have pending interrupts: + * sysint1 (16 sources, including cascading intrs from GPIO) + * sysint2 + * gpio (16 intr sources) + * + * Then we do binary search to find the exact interrupt source. + */ +ll_cpu_ip2: + + lui t3,%hi(VR4181_SYSINT1REG) + lhu t0,%lo(VR4181_SYSINT1REG)(t3) + lhu t2,%lo(VR4181_MSYSINT1REG)(t3) + and t0, 0xfffb /* hack - remove RTC Long 1 intr */ + and t0, t2 + beqz t0, check_sysint2 + + /* check for GPIO interrupts */ + andi t1, t0, 0x0100 + bnez t1, check_gpio_int + + /* so we have an interrupt in sysint1 which is not gpio int */ + li a0, VR4181_SYS_IRQ_BASE - 1 + j check_16 + +check_sysint2: + + lhu t0,%lo(VR4181_SYSINT2REG)(t3) + lhu t2,%lo(VR4181_MSYSINT2REG)(t3) + and t0, 0xfffe /* hack - remove RTC Long 2 intr */ + and t0, t2 + li a0, VR4181_SYS_IRQ_BASE + 16 - 1 + j check_16 + +check_gpio_int: + lui t3,%hi(VR4181_GPINTMSK) + lhu t0,%lo(VR4181_GPINTMSK)(t3) + lhu t2,%lo(VR4181_GPINTSTAT)(t3) + xori t0, 0xffff /* why? reverse logic? */ + and t0, t2 + li a0, VR4181_GPIO_IRQ_BASE - 1 + j check_16 + +/* + * When we reach check_16, we have 16-bit status in t0 and base irq number + * in a0. + */ +check_16: + andi t1, t0, 0xff + bnez t1, check_8 + + srl t0, 8 + addi a0, 8 + j check_8 + +/* + * When we reach check_8, we have 8-bit status in t0 and base irq number + * in a0. + */ +check_8: + andi t1, t0, 0xf + bnez t1, check_4 + + srl t0, 4 + addi a0, 4 + j check_4 + +/* + * When we reach check_4, we have 4-bit status in t0 and base irq number + * in a0. + */ +check_4: + andi t0, t0, 0xf + beqz t0, do_spurious + +loop: + andi t2, t0, 0x1 + srl t0, 1 + addi a0, 1 + beqz t2, loop + +found_it: + move a1, sp + jal do_IRQ + + j ret_from_irq + + END(vr4181_handle_irq) |