mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-11 12:28:41 +08:00
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
298 lines
7.3 KiB
ArmAsm
298 lines
7.3 KiB
ArmAsm
/*
|
|
* arch/mips/dec/int-handler.S
|
|
*
|
|
* Copyright (C) 1995, 1996, 1997 Paul M. Antoine and Harald Koerfgen
|
|
* Copyright (C) 2000, 2001, 2002, 2003 Maciej W. Rozycki
|
|
*
|
|
* Written by Ralf Baechle and Andreas Busse, modified for DECStation
|
|
* support by Paul Antoine and Harald Koerfgen.
|
|
*
|
|
* completly rewritten:
|
|
* Copyright (C) 1998 Harald Koerfgen
|
|
*
|
|
* Rewritten extensively for controller-driven IRQ support
|
|
* by Maciej W. Rozycki.
|
|
*/
|
|
#include <linux/config.h>
|
|
#include <asm/asm.h>
|
|
#include <asm/regdef.h>
|
|
#include <asm/mipsregs.h>
|
|
#include <asm/stackframe.h>
|
|
#include <asm/addrspace.h>
|
|
|
|
#include <asm/dec/interrupts.h>
|
|
#include <asm/dec/ioasic_addrs.h>
|
|
#include <asm/dec/ioasic_ints.h>
|
|
#include <asm/dec/kn01.h>
|
|
#include <asm/dec/kn02.h>
|
|
#include <asm/dec/kn02xa.h>
|
|
#include <asm/dec/kn03.h>
|
|
|
|
|
|
.text
|
|
.set noreorder
|
|
/*
|
|
* decstation_handle_int: Interrupt handler for DECStations
|
|
*
|
|
* We follow the model in the Indy interrupt code by David Miller, where he
|
|
* says: a lot of complication here is taken away because:
|
|
*
|
|
* 1) We handle one interrupt and return, sitting in a loop
|
|
* and moving across all the pending IRQ bits in the cause
|
|
* register is _NOT_ the answer, the common case is one
|
|
* pending IRQ so optimize in that direction.
|
|
*
|
|
* 2) We need not check against bits in the status register
|
|
* IRQ mask, that would make this routine slow as hell.
|
|
*
|
|
* 3) Linux only thinks in terms of all IRQs on or all IRQs
|
|
* off, nothing in between like BSD spl() brain-damage.
|
|
*
|
|
* Furthermore, the IRQs on the DECStations look basically (barring
|
|
* software IRQs which we don't use at all) like...
|
|
*
|
|
* DS2100/3100's, aka kn01, aka Pmax:
|
|
*
|
|
* MIPS IRQ Source
|
|
* -------- ------
|
|
* 0 Software (ignored)
|
|
* 1 Software (ignored)
|
|
* 2 SCSI
|
|
* 3 Lance Ethernet
|
|
* 4 DZ11 serial
|
|
* 5 RTC
|
|
* 6 Memory Controller
|
|
* 7 FPU
|
|
*
|
|
* DS5000/200, aka kn02, aka 3max:
|
|
*
|
|
* MIPS IRQ Source
|
|
* -------- ------
|
|
* 0 Software (ignored)
|
|
* 1 Software (ignored)
|
|
* 2 TurboChannel
|
|
* 3 RTC
|
|
* 4 Reserved
|
|
* 5 Memory Controller
|
|
* 6 Reserved
|
|
* 7 FPU
|
|
*
|
|
* DS5000/1xx's, aka kn02ba, aka 3min:
|
|
*
|
|
* MIPS IRQ Source
|
|
* -------- ------
|
|
* 0 Software (ignored)
|
|
* 1 Software (ignored)
|
|
* 2 TurboChannel Slot 0
|
|
* 3 TurboChannel Slot 1
|
|
* 4 TurboChannel Slot 2
|
|
* 5 TurboChannel Slot 3 (ASIC)
|
|
* 6 Halt button
|
|
* 7 FPU/R4k timer
|
|
*
|
|
* DS5000/2x's, aka kn02ca, aka maxine:
|
|
*
|
|
* MIPS IRQ Source
|
|
* -------- ------
|
|
* 0 Software (ignored)
|
|
* 1 Software (ignored)
|
|
* 2 Periodic Interrupt (100usec)
|
|
* 3 RTC
|
|
* 4 I/O write timeout
|
|
* 5 TurboChannel (ASIC)
|
|
* 6 Halt Keycode from Access.Bus keyboard (CTRL-ALT-ENTER)
|
|
* 7 FPU/R4k timer
|
|
*
|
|
* DS5000/2xx's, aka kn03, aka 3maxplus:
|
|
*
|
|
* MIPS IRQ Source
|
|
* -------- ------
|
|
* 0 Software (ignored)
|
|
* 1 Software (ignored)
|
|
* 2 System Board (ASIC)
|
|
* 3 RTC
|
|
* 4 Reserved
|
|
* 5 Memory
|
|
* 6 Halt Button
|
|
* 7 FPU/R4k timer
|
|
*
|
|
* We handle the IRQ according to _our_ priority (see setup.c),
|
|
* then we just return. If multiple IRQs are pending then we will
|
|
* just take another exception, big deal.
|
|
*/
|
|
.align 5
|
|
NESTED(decstation_handle_int, PT_SIZE, ra)
|
|
.set noat
|
|
SAVE_ALL
|
|
CLI # TEST: interrupts should be off
|
|
.set at
|
|
.set noreorder
|
|
|
|
/*
|
|
* Get pending Interrupts
|
|
*/
|
|
mfc0 t0,CP0_CAUSE # get pending interrupts
|
|
mfc0 t1,CP0_STATUS
|
|
#ifdef CONFIG_MIPS32
|
|
lw t2,cpu_fpu_mask
|
|
#endif
|
|
andi t0,ST0_IM # CAUSE.CE may be non-zero!
|
|
and t0,t1 # isolate allowed ones
|
|
|
|
beqz t0,spurious
|
|
|
|
#ifdef CONFIG_MIPS32
|
|
and t2,t0
|
|
bnez t2,fpu # handle FPU immediately
|
|
#endif
|
|
|
|
/*
|
|
* Find irq with highest priority
|
|
*/
|
|
PTR_LA t1,cpu_mask_nr_tbl
|
|
1: lw t2,(t1)
|
|
nop
|
|
and t2,t0
|
|
beqz t2,1b
|
|
addu t1,2*PTRSIZE # delay slot
|
|
|
|
/*
|
|
* Do the low-level stuff
|
|
*/
|
|
lw a0,(-PTRSIZE)(t1)
|
|
nop
|
|
bgez a0,handle_it # irq_nr >= 0?
|
|
# irq_nr < 0: it is an address
|
|
nop
|
|
jr a0
|
|
# a trick to save a branch:
|
|
lui t2,(KN03_IOASIC_BASE>>16)&0xffff
|
|
# upper part of IOASIC Address
|
|
|
|
/*
|
|
* Handle "IRQ Controller" Interrupts
|
|
* Masked Interrupts are still visible and have to be masked "by hand".
|
|
*/
|
|
FEXPORT(kn02_io_int) # 3max
|
|
lui t0,(KN02_CSR_BASE>>16)&0xffff
|
|
# get interrupt status and mask
|
|
lw t0,(t0)
|
|
nop
|
|
andi t1,t0,KN02_IRQ_ALL
|
|
b 1f
|
|
srl t0,16 # shift interrupt mask
|
|
|
|
FEXPORT(kn02xa_io_int) # 3min/maxine
|
|
lui t2,(KN02XA_IOASIC_BASE>>16)&0xffff
|
|
# upper part of IOASIC Address
|
|
|
|
FEXPORT(kn03_io_int) # 3max+ (t2 loaded earlier)
|
|
lw t0,IO_REG_SIR(t2) # get status: IOASIC sir
|
|
lw t1,IO_REG_SIMR(t2) # get mask: IOASIC simr
|
|
nop
|
|
|
|
1: and t0,t1 # mask out allowed ones
|
|
|
|
beqz t0,spurious
|
|
|
|
/*
|
|
* Find irq with highest priority
|
|
*/
|
|
PTR_LA t1,asic_mask_nr_tbl
|
|
2: lw t2,(t1)
|
|
nop
|
|
and t2,t0
|
|
beq zero,t2,2b
|
|
addu t1,2*PTRSIZE # delay slot
|
|
|
|
/*
|
|
* Do the low-level stuff
|
|
*/
|
|
lw a0,%lo(-PTRSIZE)(t1)
|
|
nop
|
|
bgez a0,handle_it # irq_nr >= 0?
|
|
# irq_nr < 0: it is an address
|
|
nop
|
|
jr a0
|
|
nop # delay slot
|
|
|
|
/*
|
|
* Dispatch low-priority interrupts. We reconsider all status
|
|
* bits again, which looks like a lose, but it makes the code
|
|
* simple and O(log n), so it gets compensated.
|
|
*/
|
|
FEXPORT(cpu_all_int) # HALT, timers, software junk
|
|
li a0,DEC_CPU_IRQ_BASE
|
|
srl t0,CAUSEB_IP
|
|
li t1,CAUSEF_IP>>CAUSEB_IP # mask
|
|
b 1f
|
|
li t2,4 # nr of bits / 2
|
|
|
|
FEXPORT(kn02_all_int) # impossible ?
|
|
li a0,KN02_IRQ_BASE
|
|
li t1,KN02_IRQ_ALL # mask
|
|
b 1f
|
|
li t2,4 # nr of bits / 2
|
|
|
|
FEXPORT(asic_all_int) # various I/O ASIC junk
|
|
li a0,IO_IRQ_BASE
|
|
li t1,IO_IRQ_ALL # mask
|
|
b 1f
|
|
li t2,8 # nr of bits / 2
|
|
|
|
/*
|
|
* Dispatch DMA interrupts -- O(log n).
|
|
*/
|
|
FEXPORT(asic_dma_int) # I/O ASIC DMA events
|
|
li a0,IO_IRQ_BASE+IO_INR_DMA
|
|
srl t0,IO_INR_DMA
|
|
li t1,IO_IRQ_DMA>>IO_INR_DMA # mask
|
|
li t2,8 # nr of bits / 2
|
|
|
|
/*
|
|
* Find irq with highest priority.
|
|
* Highest irq number takes precedence.
|
|
*/
|
|
1: srlv t3,t1,t2
|
|
2: xor t1,t3
|
|
and t3,t0,t1
|
|
beqz t3,3f
|
|
nop
|
|
move t0,t3
|
|
addu a0,t2
|
|
3: srl t2,1
|
|
bnez t2,2b
|
|
srlv t3,t1,t2
|
|
|
|
handle_it:
|
|
jal do_IRQ
|
|
move a1,sp
|
|
|
|
j ret_from_irq
|
|
nop
|
|
|
|
#ifdef CONFIG_MIPS32
|
|
fpu:
|
|
j handle_fpe_int
|
|
nop
|
|
#endif
|
|
|
|
spurious:
|
|
j spurious_interrupt
|
|
nop
|
|
END(decstation_handle_int)
|
|
|
|
/*
|
|
* Generic unimplemented interrupt routines -- cpu_mask_nr_tbl
|
|
* and asic_mask_nr_tbl are initialized to point all interrupts here.
|
|
* The tables are then filled in by machine-specific initialisation
|
|
* in dec_setup().
|
|
*/
|
|
FEXPORT(dec_intr_unimplemented)
|
|
move a1,t0 # cheats way of printing an arg!
|
|
PANIC("Unimplemented cpu interrupt! CP0_CAUSE: 0x%08x");
|
|
|
|
FEXPORT(asic_intr_unimplemented)
|
|
move a1,t0 # cheats way of printing an arg!
|
|
PANIC("Unimplemented asic interrupt! ASIC ISR: 0x%08x");
|