vectors.s

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	# stack. We will be executing either on the same stack
	# or on the interrupt stack, depending on config options.
		
	hal_intc_decode d3,a3,d0

	# Here D3 contains the table byte offset of the vector to
	# call.

#if defined(CYGPKG_KERNEL_INSTRUMENT) && defined(CYGDBG_KERNEL_INSTRUMENT_INTR)

	# Call cyg_instrument to record that this interrupt is being raised.

	.extern _cyg_instrument		
	add	-16,sp				# make space for return link + args	
	mov	0x0301,d0			# d0 = type = INTR,RAISE
	mov	(0,a2),d1			# d1 = arg1 = vector
	mov	d3,(12,sp)			# (12,sp) = arg2 = table offset
	calls	_cyg_instrument			# call instrumentation
	add	16,sp				# pop space
	
#endif		

#ifdef CYGDBG_HAL_DEBUG_GDB_BREAK_SUPPORT
        .extern _cyg_hal_gdb_isr
        add     -16,sp                          # make space for return link + args
        mov     (0,a2),d0                       # d0 = vector
        mov     (SAVED_CONTEXT_PC_OFFSET,a2),d1 # d1 = pc
        calls   _cyg_hal_gdb_isr                # call GDB isr function
        cmp     0x00,d0                         # Call ISR proper?
        beq     2f                              # (d0 is 0 when skipping
                                                #  to avoid DSR call)
        add     16,sp                           # pop space
#endif
	
#ifdef CYGSEM_HAL_COMMON_INTERRUPTS_ALLOW_NESTING

	# To allow nested interrupts, we set the IE bit. We do
	# not touch the IPL bits, so only higher priority interrupts
	# will be nested on top of us. Also, new interrupts will not
	# be delivered until the ISR calls 
	# Cyg_Interrupt::acknowledge_interrupt(). At some future point
	# we may want to do the ack stuff here to allow immediate nesting.
	
	or	0x0800,psw
	
#endif
#if defined(CYGDBG_HAL_DEBUG_GDB_CTRLC_SUPPORT)

	# If we have Ctrl-C support enabled, save a pointer to the
	# saved CPU state here so we can plant a breakpoint there if
	# this is a ^C.
	
	.extern _hal_saved_interrupt_state
	mov	a2,(_hal_saved_interrupt_state)
	
#endif
		
	mov	_hal_interrupt_handlers,a0	# a0 = isr table
	mov	(d3,a0),a0			# a0 = isr
	
	mov	_hal_interrupt_data,a1		# a1 = data table
	mov	(d3,a1),d1			# d1 = isr data

	mov	(0,a2),d0			# d0 = vector. (d3 is...
						# ...adjusted for table reads)

	add	-16,sp				# make space for return link

	calls	(a0)				# call isr

	# on return d0 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.
	
	# D3 is defined to be saved across procedure calls, and
	# should still contain the vector byte index. Similarly,
	# A2 should still point to the saved machine state.

#ifdef CYGDBG_HAL_DEBUG_GDB_BREAK_SUPPORT
        # If interrupt was caused by GDB, the ISR call above
        # is skipped by jumping here.
2:
#endif

#if defined(CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK) && !defined(CYGPKG_CYGMON)

	# 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.
	
	add	16,sp				# pop call frame from int stack
	movm	(sp),[a3]			# pop old sp
	mov	a3,sp				# put in SP

	add	-16,sp				# make call frame for call

#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.
		
	# Using the vector offset in D3, get the interrupt object pointer
	# into D1.
	mov	_hal_interrupt_objects,a0	# a0 = object table
	mov	(d3,a0),d1			# d1 = object

	# Even when this is not the last nested interrupt, we must call
	# _interrupt_end() to post the DSR and decrement the scheduler
	# lock.
		
	mov	a2,(12,sp)			# arg3 = saved state.
	
	calls	_interrupt_end			# call interrupt end fn		
#endif

	add	16,sp				# pop return link

#	show_interrupts

	hal_diag_restore
	
	hal_cpu_load_all
#ifdef CYGPKG_CYGMON
	hal_cygmon_restore_app_stack
#else
	add	4,sp
#endif
	rti					# and return

##-----------------------------------------------------------------------------
## Execute pending DSRs on the interrupt stack with interrupts enabled.
## Note: this can only be called from code running on a thread stack
	
#ifdef CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK
	.extern _cyg_interrupt_call_pending_DSRs
	.global _hal_interrupt_stack_call_pending_DSRs

_hal_interrupt_stack_call_pending_DSRs:		
	movm	[d2,a2],(sp)			# save some work regs
	mov	__interrupt_stack,a0		# interrupt stack pointer
	mov	sp,a2				# save current SP
	mov	a0,sp				# set SP to interrupt stack
	hal_cpu_get_psw d2			# save PSW
	hal_cpu_int_enable			# enable interrupts

	# Call kernel code to invoke DSRs.
	calls	_cyg_interrupt_call_pending_DSRs	

	# On return the old SP in a2 and the old PSW in d2 will 
	# have been preserved by the calling conventions.
	
	hal_cpu_int_merge d2			# Restore previous PSW
	mov	a2,sp				# restore old SP
	movm	(sp),[d2,a2]			# Retrieve old work regs
	ret	[],0				# and return
		
#endif		
		
##-----------------------------------------------------------------------------
## Default NMI VSR

	.globl	_cyg_hal_exception_handler
	
	.text
	.globl	__default_nmi_vsr
__default_nmi_vsr:

	# We come here with all the registers saved
	# on the stack.

#ifdef CYG_HAL_DIAG_EXCPT_END
	hal_diag_excpt_start
#endif
	
	# Decode the cause of the NMI and cancel all the bits in all
	# the registers. We need to clear any bits set in the ISR and
	# then clear any bits set in the NMICR. Note that we can only 
	# access the ISR if the DCR:DE bit is set. 
	
	movhu	(NMICR),d0			# D0 = NMI Control register

	movhu	(DCR),d1			# D1 = Debug Control Register
	mov	d1,d2				# D2 = copy of DCR
	movhu	(ISR),d3			# D3 = Interrupt Status Register

	or	DCR_DE,d1			# Set DE bit	
	movhu	d1,(DCR)			

	movhu	d3,(ISR)			# clear ISR bits

	movhu	d2,(DCR)			# restore DCR to original value

	movhu	d0,(NMICR)			# clear NMI bits
	and	0x7,d0				# LS 3 bits only

	mov	hal_lsbit_table,a0		
	movbu	(d0,a0),d1			# D1 = NMI code
						## 0 = NMI
						## 1 = Watchdog
						## 2 = System Error

	add	9,d1				# offset into exception number space
	
#if defined(CYGPKG_CYGMON) || defined(CYGSEM_REDBOOT_BSP_SYSCALLS)
	# Check to see if this was a syscall.
	# If so, set d1 appropriately
#define TBR 0xC0000024
	mov	(TBR), d0
	and	0x00FFFFFF, d0
	cmp	0x300, d0
	bne	0f

	# This was apparently a syscall.
	mov     SIGSYSCALL, d1

0:	
#endif
	hal_cpu_clear_nmid

	mov	d1,(sp)				# save initial vector in spare save slot
        
	mov	sp,a1				# a1 = saved state

	mov	a1,d0				# d0 = arg1 = saved state

	add	-16,sp				# return link + args
	mov	d3,d1				# d1 = arg2 = ISR value

	calls	_cyg_hal_exception_handler	# call C code

	add	16,sp				# pop args

#ifdef CYG_HAL_DIAG_EXCPT_END
	hal_diag_excpt_end
#endif

	hal_cpu_load_all

#ifdef CYGPKG_CYGMON
	hal_cygmon_restore_app_stack
#else
	add	4,sp
#endif

	rti

	.globl hal_lsbit_table
hal_lsbit_table:
	.byte	0, 0, 1, 0
	.byte	2, 0, 1, 0
	.byte	3, 0, 1, 0
	.byte	2, 0, 1, 0
	
#ifdef CYGPKG_CYGMON
        .section ".bss"
d0_save:
	.long	0
d1_save:
	.long	0
d2_save:
	.long	0
d3_save:
	.long	0
a0_save:
	.long	0
a1_save:
	.long	0
a2_save:
	.long	0
a3_save:
	.long	0
sp_save:
	.long	0
#endif

##-----------------------------------------------------------------------------
## Default TRAP VSR

	.text
	.globl	__default_trap_vsr
__default_trap_vsr:

#ifdef CYG_HAL_DIAG_EXCPT_END
	hal_diag_excpt_start
#endif

	# We come here with all the registers saved
	# on the stack.
	mov	8,d1
	mov	d1,(sp)				# set the VSR vector number
	mov	sp,a1				# a1 = saved state
	mov	a1,d0				# d0 = arg1 = saved state

	add	-16,sp				# return link + arg
	mov	3,d1				# d1 = arg2 = ISR value (3 == TRAP trap)
	calls	_cyg_hal_exception_handler	# call C code
	add	16,sp				# pop args

#ifdef CYG_HAL_DIAG_EXCPT_END
	hal_diag_excpt_end
#endif
	hal_cpu_load_all
#ifdef CYGPKG_CYGMON
	hal_cygmon_restore_app_stack
	add	4,sp
#else
	add	8,sp
#endif
	rets

##-----------------------------------------------------------------------------
## VSR table. The VSRs pointed to by this table are called from the stubs
## connected to the hardware.

#ifndef CYG_HAL_MN10300_VSR_TABLE_DEFINED
	
	.data

	.globl	_hal_vsr_table
_hal_vsr_table:	
	.long	__default_interrupt_vsr
	.long	__default_interrupt_vsr
	.long	__default_interrupt_vsr
	.long	__default_interrupt_vsr
	.long	__default_interrupt_vsr
	.long	__default_interrupt_vsr
	.long	__default_interrupt_vsr
	.long	__default_nmi_vsr
	.long	__default_trap_vsr

	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
	.long	__default_nmi_vsr
#endif
	
##-----------------------------------------------------------------------------
## Interrupt tables
	
	.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
	
			
##-----------------------------------------------------------------------------
## Temporary interrupt stack
	
	.section ".bss"

	.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:
	
#ifdef CYGPKG_CYGMON
	.balign 16
	.global __cygmon_interrupt_stack_base
__cygmon_interrupt_stack_base:
	.rept CYGNUM_HAL_COMMON_INTERRUPTS_STACK_SIZE
	.byte 0
	.endr
	.balign 16
	.global __cygmon_interrupt_stack
__cygmon_interrupt_stack:
#endif

	.long	0,0,0,0,0,0,0,0	

##-----------------------------------------------------------------------------

	.data
	hal_diag_data

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