vectors.s

eCos1.31版

# Common interrupt handling code.

        .globl _cyg_hal_default_interrupt_vsr
_cyg_hal_default_interrupt_vsr:

        # We come here with all register containing their
        # pre-exception values except:
        # r0_b-r7_b  = saved r0-r7
        # r7    = vector #
        # spc   = saved pc
        # ssr   = saved sr
        
        # Save away some registers
        mov     r15,r1                  ! entry sp

#ifdef __DEBUG
        mov.l   $int_state_marker,r0
        mov.l   r0,@-r15
        mov     #CYGARC_REG_INTEVT,r0
        mov.l   @r0,r0
        mov.l   r0,@-r15
#endif
        
#ifdef CYGDBG_HAL_COMMON_INTERRUPTS_SAVE_MINIMUM_CONTEXT
        add     #-12,r15                ! Space for cause, gbr, and vbr
#else
        add     #-4,r15                 ! Space for cause

        stc     gbr,r0                  ! GBR
        mov.l   r0,@-r15
        stc     vbr,r0                  ! VBR
        mov.l   r0,@-r15
#endif

        stc     spc,r0
        mov.l   r0,@-r15                ! PC
        stc     ssr,r0
        mov.l   r0,@-r15                ! SR

        sts.l   pr,@-r15                ! PR
        sts.l   mach,@-r15              ! mach
        sts.l   macl,@-r15              ! macl

        mov.l   r1,@-r15                ! entry sp
        mov.l   r14,@-r15               ! r14-r0
        mov.l   r13,@-r15
        mov.l   r12,@-r15
        mov.l   r11,@-r15
        mov.l   r10,@-r15
        mov.l   r9,@-r15
        mov.l   r8,@-r15
        stc.l   r7_bank,@-r15
        stc.l   r6_bank,@-r15
        stc.l   r5_bank,@-r15
        stc.l   r4_bank,@-r15
        stc.l   r3_bank,@-r15
        stc.l   r2_bank,@-r15
        stc.l   r1_bank,@-r15
        stc.l   r0_bank,@-r15

        # After setting the SR it will be possible to use breakpoints.
        mov.l   $nCYG_SR2,r1
        ldc     r1,sr
        # ------------------------------------------------------------
        # Register bank has changed now. 

#ifdef __DEBUG
        # It is safe to use breakpoints below this point.
        .globl  _cyg_hal_default_interrupt_vsr_bp_safe
_cyg_hal_default_interrupt_vsr_bp_safe:
#endif

        # The entire CPU state is now stashed on the stack,
        # call into C to do something with it.

        # The entire CPU state is now stashed on the stack,
        # increment the scheduler lock and call the ISR
        # for this vector.

#ifdef CYGFUN_HAL_COMMON_KERNEL_SUPPORT                 
        mov.l   $cyg_scheduler_sched_lock,r0
        mov.l   @r0,r1
        add     #1,r1
        mov.l   r1,@r0
#endif

        mov     r15,r8                  ! R8 = register dump

#ifdef CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK 

        mov.l   $__interrupt_stack_base,r0
        mov.l   $__interrupt_stack,r1
        cmp/hi  r15,r0                  ! if r0 > r15 or
        bt      2f
        cmp/hi  r1,r15                  ! if r15 > r1
        bf      1f
2:      mov     r1,r15                  ! change to supervisor stack
1:      mov.l   r8,@-r15                ! save old stack pointer

#endif

#if defined(CYGPKG_KERNEL_INSTRUMENT) && defined(CYGDBG_KERNEL_INSTRUMENT_INTR)
        mov.l   $n0301,r4               ! arg0 = type = INTR,RAISE
        mov     r7,r5                   ! arg1 = vector number
        mov.l   $_cyg_instrument,r0
        mov     #0,r6                   ! arg2 = 0
        jsr      @r0                    ! call instrument function
         nop
        bra     1f
         nop

        .align  2
$n0301: 
        .long   0x0301
$_cyg_instrument:
        .extern _cyg_instrument
        .long   _cyg_instrument
1:
#endif

        # Decode the interrupt vector
        mov     #CYGARC_REG_INTEVT,r0
        mov.l   @r0,r4
        mov     #-5,r0                  ! divide cause by 0x20
        shld    r0,r4
        add     #-14,r4                 ! adjust so NMI becomes 0
        mov     #CYGARC_SHREG_EVENT,r0
        mov.l   r4,@(r0,r8)             ! store decoded vector number back
                                        ! to saved state.

        // Find ISR index.
#ifdef CYGIMP_HAL_COMMON_INTERRUPTS_CHAIN
#define CYG_ISR_TABLE_SIZE    1
        mov     #0,r9                   ! only one ISR in the table
#else //  CYGIMP_HAL_COMMON_INTERRUPTS_CHAIN
#define CYG_ISR_TABLE_SIZE    CYGNUM_HAL_ISR_COUNT
        mov     r4,r9
        shll2   r9                      ! get from vector number to ISR index
#endif //  CYGIMP_HAL_COMMON_INTERRUPTS_CHAIN


#ifdef CYGDBG_HAL_DEBUG_GDB_BREAK_SUPPORT
        mov     #CYGNUM_HAL_INTERRUPT_SCI_RXI,r1
        cmp/eq  r1,r4
        bf      2f
        mov     r4,r10                   ! save across call.
        mov     #CYGARC_SHREG_PC,r4
        add     r8,r4
        mov.l   @r4,r4
        mov.l   $_cyg_hal_gdb_isr,r1
        jsr     @r1                     ! returns 1 if the proper isr must be
         nop                            ! called (i.e., if it was not a GDB 
        mov     r10,r4                  ! interrupt)
        cmp/eq  #0,r0
        bt      skip_isr_proper
        bra     2f
         nop
        .align  2
        .extern _cyg_hal_gdb_isr
$_cyg_hal_gdb_isr:
        .long   _cyg_hal_gdb_isr
2:
#endif

#ifdef CYGSEM_HAL_COMMON_INTERRUPTS_ALLOW_NESTING

#ifdef CYGPKG_HAL_SH_EDK7708
        # The interrupt mask bits in the SR are not updated by the
        # CPU. Proper nested operation requires the level to be
        # found and put in the SR.

        # R4 contains the vector number:
        # CYGNUM_HAL_INTERRUPT_NMI:     
        #  Ix = 15
        # CYGNUM_HAL_INTERRUPT_LVL0-CYGNUM_HAL_INTERRUPT_LVL14:
        #  Ix = 15-(CYGNUM_HAL_INTERRUPT_LVL0-R4)
        # IRA sources:
        #  Get level from IRA
        # IRB sources:
        #  Get level from IRB

        # However, doing mutiple checks and branches here is not smart.
        # Instead rely on alternative implementation where all programmed
        # priorities are also kept in a table.

        mov.l   $cyg_hal_ILVL_table,r0
        mov.b   @(r0,r4),r0
        shll2   r0
        shll2   r0
        mov.l   $unmasked_SR,r1
        or      r0,r1
        ldc     r1,sr
#endif

#endif

        mov     r9,r0
        mov.l   $_hal_interrupt_handlers,r1 ! get interrupt handler
        mov.l   @(r0,r1),r1

        mov.l   $_hal_interrupt_data,r5 ! get interrupt data
        mov.l   @(r0,r5),r5

        jsr     @r1                     ! r4=vector, r5=data
         nop

#ifdef CYGDBG_HAL_DEBUG_GDB_BREAK_SUPPORT
        # If interrupt was caused by GDB, the ISR call above
        # is skipped by jumping here.
skip_isr_proper:
#endif

#ifdef CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK

        # If we are returning from the last nested interrupt, move back
        # to the thread stack. interrupt_end() must be called on the
        # thread stack since it potentially causes a context switch.
        # Since we have arranged for the top of stack location to
        # contain the sp we need to go back to here, just pop it off
        # and put it in SP.

        mov.l   @r15,r15
#endif

#ifdef CYGFUN_HAL_COMMON_KERNEL_SUPPORT

        # We only need to call _interrupt_end() when there is a kernel
        # present to do any tidying up.
        
        # on return r0 bit 1 will indicate whether a DSR is
        # to be posted. Pass this together with a pointer to
        # the interrupt object we have just used to the
        # interrupt tidy up routine.
        mov     r0,r4                   ! arg1 = isr_ret

        # Note that r8 and r9 are defined to be preserved across
        # calls by the calling convention, so they still contain
        # the register dump and the vector table index respectively.

        mov.l   $_hal_interrupt_objects,r0  ! get interrupt object table
        mov.l   @(r0,r9),r5             ! arg2 = interrupt object
        mov.l   $_interrupt_end,r0
        mov     r8,r6                   ! arg3 = saved register dump
        jsr     @r0                     ! call into C to finish off
         nop
#endif

restore_state:  
        # All done, restore CPU state and continue
#ifdef __DEBUG
        mov.l   $_safe_addr,r0
        mov.l   @r0,r1
        add     #1,r1
        mov.l   r1,@r0
        add     #4,r0

        mov     r15,r1
        mov     #CYGARC_SH_EXCEPTION_SIZE/4,r2
1:      mov.l   @r1+,r3
        mov.l   r3,@r0
        add     #4,r0
        dt      r2
        bf      1b

        bra     2f
         nop
        .align  2
$_safe_addr:
        .long   0x080d0000-4
2:      
#endif

        # Disable interrupts and switch register bank during the restore 
        # operation
        mov.l   $nCYG_SR_BANK1,r1
        ldc     r1,sr
        # ------------------------------------------------------------
        # Register bank has changed now. 

        #
        # Single step debugging becomes impossible after this point!
        #

        mov     r15,r0
        ldc.l   @r0+,r0_bank
        ldc.l   @r0+,r1_bank
        ldc.l   @r0+,r2_bank
        ldc.l   @r0+,r3_bank
        ldc.l   @r0+,r4_bank
        ldc.l   @r0+,r5_bank
        ldc.l   @r0+,r6_bank
        ldc.l   @r0+,r7_bank
        mov.l   @r0+,r8
        mov.l   @r0+,r9
        mov.l   @r0+,r10
        mov.l   @r0+,r11
        mov.l   @r0+,r12
        mov.l   @r0+,r13
        mov.l   @r0+,r14
        mov.l   @r0+,r15                ! return SP

        lds.l   @r0+,macl               ! macl
        lds.l   @r0+,mach               ! mach
        lds.l   @r0+,pr                 ! PR

        mov.l   @r0+,r2
        ldc     r2,ssr                  ! return SR
        mov.l   @r0+,r2
        ldc     r2,spc                  ! return PC

#ifndef CYGDBG_HAL_COMMON_INTERRUPTS_SAVE_MINIMUM_CONTEXT
        mov.l   @r0+,r2
        ldc     r2,vbr                  ! return VBR
        mov.l   @r0+,r2
        ldc     r2,gbr                  ! return GBR
#endif

        rte
         nop


#ifdef CYGFUN_HAL_COMMON_KERNEL_SUPPORT
#ifdef CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK
##-----------------------------------------------------------------------------
## Execute pending DSRs on the interrupt stack with interrupts enabled.
## Note: this can only be called from code running on a thread stack
        .globl _hal_interrupt_stack_call_pending_DSRs
_hal_interrupt_stack_call_pending_DSRs: 
        # Change to interrupt stack
        mov     r15,r2
        mov.l   $__interrupt_stack,r15

        mov.l   r2,@-r15                ! save old stack pointer
        sts.l   pr,@-r15                ! save pr on stack
        stc     sr,r3
        mov.l   r3,@-r15                ! save sr on stack

        # enable interrupts
        hal_cpu_int_enable r0,r1

        # Call into kernel which will execute DSRs
        mov.l   $_cyg_interrupt_call_pending_DSRs,r0
        jsr     @r0
         nop

        # Get old sr, pr, and stack values
        mov.l   @r15+,r3                ! get old sr
        lds.l   @r15+,pr                ! get old pr
        mov.l   @r15+,r15               ! get old stack pointer

        # Restore SR interrupt state
        hal_cpu_int_merge r3,r0,r1
        rts
         nop

#endif // CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK
#endif // CYGFUN_HAL_COMMON_KERNEL_SUPPORT

        .align  2        
#ifdef __DEBUG
$int_state_marker:
        .long   0x77777771
#endif

#ifdef CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK 
$__interrupt_stack:
        .long   __interrupt_stack
$__interrupt_stack_base:
        .long   __interrupt_stack_base
#endif
$nCYG_SR2:
        .long   CYG_SR
$nCYG_SR_BANK1:
        .long   CYG_SR_BANK1
$_hal_interrupt_handlers:
        .long   _hal_interrupt_handlers
$_hal_interrupt_data:
        .long   _hal_interrupt_data
$_hal_interrupt_objects:
        .long   _hal_interrupt_objects

#ifdef CYGSEM_HAL_COMMON_INTERRUPTS_ALLOW_NESTING
$cyg_hal_ILVL_table:
        .long   _cyg_hal_ILVL_table
$unmasked_SR:
        .long   (CYG_SR & ~CYGARC_REG_SR_IMASK)
#endif // CYGSEM_HAL_COMMON_INTERRUPTS_ALLOW_NESTING
        
        
#ifdef CYGFUN_HAL_COMMON_KERNEL_SUPPORT
        .extern _cyg_scheduler_sched_lock
        .extern _interrupt_end
        .extern _cyg_interrupt_call_pending_DSRs

$_cyg_interrupt_call_pending_DSRs:
        .long   _cyg_interrupt_call_pending_DSRs
$cyg_scheduler_sched_lock:
        .long   cyg_scheduler_sched_lock
$_interrupt_end:
        .long   _interrupt_end
#endif

#---------------------------------------------------------------------------
# Interrupt vector tables.
# These tables contain the isr, data and object pointers used to deliver
# interrupts to user code.

        .data

        .extern _hal_default_isr

        .globl  _hal_interrupt_handlers
_hal_interrupt_handlers:
        .rept   CYG_ISR_TABLE_SIZE
        .long   _hal_default_isr
        .endr

        .globl  _hal_interrupt_data
_hal_interrupt_data:
        .rept   CYG_ISR_TABLE_SIZE
        .long   0
        .endr

        .globl  _hal_interrupt_objects
_hal_interrupt_objects:
        .rept   CYG_ISR_TABLE_SIZE
        .long   0
        .endr

#ifdef CYGSEM_HAL_COMMON_INTERRUPTS_ALLOW_NESTING
        .globl  _cyg_hal_ILVL_table
_cyg_hal_ILVL_table:
        # The first entries in the table have static priorities.

        .byte   0xf                     // NMI
        .byte   0xf                     // Reserved
        .byte   0xf                     // LVL0
        .byte   0xe                     // LVL1
        .byte   0xd                     // LVL2
        .byte   0xc                     // LVL3
        .byte   0xb                     // LVL4
        .byte   0xa                     // LVL5
        .byte   0x9                     // LVL6
        .byte   0x8                     // LVL7
        .byte   0x7                     // LVL8
        .byte   0x6                     // LVL9
        .byte   0x5                     // LVL10
        .byte   0x4                     // LVL11
        .byte   0x3                     // LVL12
        .byte   0x2                     // LVL13
        .byte   0x1                     // LVL14
        .byte   0xf                     // Reserved

        # The rest of the table consists of programmable levels, maintained
        # by the HAL_INTERRUPT_SET_LEVEL macro.
#ifdef CYGPKG_HAL_SH_EDK7708
        .rept   (CYGNUM_HAL_ISR_MAX-CYGNUM_HAL_INTERRUPT_RESERVED_3E0)
        .byte   0xf
        .endr
#endif // CYGPKG_HAL_SH_EDK7708
#endif // CYGSEM_HAL_COMMON_INTERRUPTS_ALLOW_NESTING

#---------------------------------------------------------------------------
## Temporary interrupt stack
        
        .section ".bss"

#ifdef CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK 
        .balign 16
        .global _cyg_interrupt_stack_base
_cyg_interrupt_stack_base:
__interrupt_stack_base:
        .rept CYGNUM_HAL_COMMON_INTERRUPTS_STACK_SIZE
        .byte 0
        .endr
        .balign 16
        .global _cyg_interrupt_stack
_cyg_interrupt_stack:
__interrupt_stack:
        
        .long   0,0,0,0
#endif // CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK


#ifdef CYGSEM_HAL_ROM_MONITOR
  // Enough space for stub to handle downloads. If using thread capabilities
  // it will be using the RAM application's stack.
# define STARTUP_STACK_SIZE 1024
#else
# ifdef CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK
   // Enough space to run constructors.
   // FIXME: 512 is enough for all tests. doc/examples/twothreads
   // calls printf on this stack though, and so requires more space.
#  define STARTUP_STACK_SIZE 1024
# else
#  define STARTUP_STACK_SIZE CYGNUM_HAL_COMMON_INTERRUPTS_STACK_SIZE
# endif
#endif

        .balign 16
__startup_stack_base:
        .rept   STARTUP_STACK_SIZE
        .byte 0
        .endr
        .balign 16
__startup_stack:
        .long   0,0,0,0

#---------------------------------------------------------------------------
# end of vectors.S