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##==========================================================================

##

##      vectors.S

##

##      SH exception vectors

##

##==========================================================================

#####ECOSGPLCOPYRIGHTBEGIN####

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

## This file is part of eCos, the Embedded Configurable Operating System.

## Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.

##

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## for more details.

##

## You should have received a copy of the GNU General Public License along

## with eCos; if not, write to the Free Software Foundation, Inc.,

## 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.

##

## As a special exception, if other files instantiate templates or use macros

## or inline functions from this file, or you compile this file and link it

## with other works to produce a work based on this file, this file does not

## by itself cause the resulting work to be covered by the GNU General Public

## License. However the source code for this file must still be made available

## in accordance with section (3) of the GNU General Public License.

##

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##

## Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.

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

#####ECOSGPLCOPYRIGHTEND####

##==========================================================================

#######DESCRIPTIONBEGIN####

##

## Author(s):    jskov

## Contributors: jskov, gthomas

## Date:         1999-05-01

## Purpose:      SH exception vectors

## Description:  This file defines the code placed into the exception

##               vectors. It also contains the first level default VSRs

##               that save and restore state for both exceptions and

##               interrupts.

##

######DESCRIPTIONEND####

##

##==========================================================================

#include 

#include 

#ifdef CYGPKG_KERNEL

#include      // CYGPKG_KERNEL_INSTRUMENT

#endif

#include CYGHWR_MEMORY_LAYOUT_H

#include 

#include 

#include 

#include 

#===========================================================================

//        .file   "vectors.S"

#define n__DEBUG

#===========================================================================

# Start by defining the exceptions vectors.

        .section ".vectors","ax"

# Include exception entry code since it exists in two variants,

# depending on the CPU model. This file also defines macros used

# for exception return.

FUNC_START(_vector_code_vma)

#include CYGBLD_HAL_VAR_EXCEPTION_MODEL_INC

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

# This code handles the common part of all exception handlers.

# It saves the machine state onto the stack  and then calls

# a "C" routine to do the rest of the work. This work may result

# in thread switches, and changes to the saved state. When we return

# here the saved state is restored and execution is continued.

FUNC_START(cyg_hal_default_exception_vsr)

        hal_cpu_save_regs

        hal_exception_entry_extras

#ifdef __DEBUG

        mov.l   1f,r0

        mov.l   r0,@-r15

        bra     2f

         nop

        .align  2

1:      .long   0x77777770

2:

        # It is safe to use breakpoints below this point.

        .globl  _cyg_hal_default_exception_vsr_bp_safe

_cyg_hal_default_exception_vsr_bp_safe:

#endif

        # Make sure the saved registers structure contain

        # the decoded exception number

        hal_exception_translate

        # The entire CPU state is now stashed on the stack,

        # call into C to do something with it.

        mov      r15,r4                 ! R4 = register dump

        mov.l   $restore_state,r0       ! get return link

        lds     r0,pr                   ! to procedure register

        mov.l   $cyg_hal_exception_handler,r0

        jmp     @r0                     ! call C code, r4 = registers

         nop

        .align  2

$restore_state:

        .long   restore_state

        SYM_PTR_REF(cyg_hal_exception_handler)

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

# Common interrupt handling code.

FUNC_START(cyg_hal_default_interrupt_vsr)

        hal_cpu_save_regs

        hal_interrupt_entry_extras

#ifdef __DEBUG

        mov.l   1f,r0

        mov.l   r0,@-r15

        bra     2f

         nop

        .align  2

1:      .long   0x77777771

2:

        # 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,

        # 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   $cyg_interrupt_stack_base,r0

        mov.l   $cyg_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

        SYM_PTR_REF(cyg_instrument)

1:

#endif

        # Decode the interrupt vector, and find ISR index

        mov     #CYGARC_SHREG_EVENT,r0

        mov.l   @(r0,r8),r4             ! load existing vector number

        hal_intc_decode r1,r4

        mov.l   r4,@(r0,r8)             ! store decoded vector number back

                                        ! to saved state.

        hal_intc_translate r4,r9

#if defined(CYGDBG_HAL_DEBUG_GDB_CTRLC_SUPPORT) \

    || defined(CYGDBG_HAL_DEBUG_GDB_BREAK_SUPPORT)

        # If we are supporting Ctrl-C interrupts from GDB, we must squirrel

        # away a pointer to the save interrupt state here so that we can

        # plant a breakpoint at some later time.

        mov.l   $hal_saved_interrupt_state,r1

        mov.l   r8,@r1

#endif

#ifdef CYGSEM_HAL_COMMON_INTERRUPTS_ALLOW_NESTING

#if defined(CYGARC_SH_SOFTWARE_IP_UPDATE)

        # 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 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

        # skip past debug marker

        add     #4,sp

#endif

        hal_cpu_restore_regs_return

#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

FUNC_START(hal_interrupt_stack_call_pending_DSRs)

        # Change to interrupt stack

        mov     r15,r2

        mov.l   $cyg_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

#if defined(CYGDBG_HAL_DEBUG_GDB_CTRLC_SUPPORT) \

    || defined(CYGDBG_HAL_DEBUG_GDB_BREAK_SUPPORT)

        SYM_PTR_REF(hal_saved_interrupt_state)

#endif

#ifdef CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK

        SYM_PTR_REF(cyg_interrupt_stack_base)

        SYM_PTR_REF(cyg_interrupt_stack)

#endif

        SYM_PTR_REF(hal_interrupt_handlers)

        SYM_PTR_REF(hal_interrupt_data)

        SYM_PTR_REF(hal_interrupt_objects)

#ifdef CYGSEM_HAL_COMMON_INTERRUPTS_ALLOW_NESTING

        SYM_PTR_REF(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

        SYM_PTR_REF(cyg_interrupt_call_pending_DSRs)

        SYM_PTR_REF(interrupt_end)

        SYM_PTR_REF(cyg_scheduler_sched_lock)

#endif

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

# Platform initialization (reset)

FUNC_START(_reset_platform)

        hal_post_reset_init

#ifdef __DEBUG

        mov     #0,r0

        mov     #1,r1

        mov     #2,r2

        mov     #3,r3

        mov     #4,r4

        mov     #5,r5

        mov     #6,r6

        mov     #7,r7

        mov     #8,r8

        mov     #9,r9

        mov     #10,r10

        mov     #11,r11

        mov     #12,r12

        mov     #13,r13

        mov     #14,r14

#endif

        # Call platform specific hardware initialization

        # This may include memory controller initialization. It is not

        # safe to access RAM until after this point.

        # Note that caches must not be enabled until after this point,

        # since we may be fiddling the FRQCR which cannot be safely done

        # by code in burst/cachable memory (errata SH7-184e).

        hal_hardware_init

        # Now copy necessary bits to RAM and jump to the VMA base

#if defined(CYG_HAL_STARTUP_ROM) || defined(CYG_HAL_STARTUP_SUBSETROMRAM)

        # Copy data from ROM to ram

        mov.l   $_rom_data_start,r3    ! r3 = rom start

        mov.l   $_ram_data_start,r4    ! r4 = ram start

        mov.l   $_ram_data_end,r5      ! r5 = ram end

        cmp/eq  r4,r5                   ! skip if no data

        bt      2f

1:      mov.l   @r3+,r0                 ! get word from ROM

        mov.l   r0,@r4                  ! store in RAM

        add     #4,r4

        cmp/eq  r4,r5                   ! compare

        bf      1b                      ! loop if not yet done

2:

        # Jump to the proper VMA base of the code.

        mov.l   $complete_setup,r0

        jmp     @r0

         nop

        .align 2

        SYM_PTR_REF(_rom_data_start)

        SYM_PTR_REF(_ram_data_start)

        SYM_PTR_REF(_ram_data_end)

        SYM_PTR_REF(complete_setup)

#elif defined(CYG_HAL_STARTUP_ROMRAM)

        # Copy everything to the proper VMA base and jump to it.

        mov.l   $_vector_code_lma,r0

        mov.l   $_vector_code_vma,r1

        mov.l   $end,r2

1:      mov.l   @r0+,r3                 ! get word from ROM

        mov.l   r3,@r1                  ! store in RAM

        add     #4,r1

        cmp/eq  r1,r2                   ! compare

        bf      1b                      ! loop if not yet done

        mov.l   $complete_setup,r0

        jmp     @r0

         nop

        .align  2

        SYM_PTR_REF(_vector_code_lma)

        SYM_PTR_REF(_vector_code_vma)

        SYM_PTR_REF(end)

        SYM_PTR_REF(complete_setup)

#else

        # Jump to remaining setup code. Relative branch is OK since VMA=LMA.

        bra   CYG_LABEL_DEFN(complete_setup)

         nop

#endif

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

# Complete target initialization and setup.

# After this point we can use absolute addressing modes and access all the

# memory in the system.

        .align  2

FUNC_START(complete_setup)

        # Set up monitor related stuff (vectors primarily)

        hal_mon_init

        # set up stack

        mov.l    $startup_stack,r15

        # clear BSS

        mov.l   $_bss_start,r3         ! r3 = start

        mov.l   $_bss_end,r4           ! r4 = end

        mov     #0,r0                   ! r0 = 0

1:      cmp/eq  r3,r4                   ! skip if no bss

        bt      2f

        mov.l   r0,@r3                  ! store zero

        add     #4,r3

        bra     1b                      ! loop

         nop

2:

        # It is now safe to call C functions which may rely on initialized

        # data.

#        # Initialize MMU.

#        .extern hal_MMU_init

#        jsr      hal_MMU_init

#         nop

        # Enable caches

        mov.l    $cyg_var_enable_caches,r1

        jsr      @r1

         nop

        # Variant HALs may need to do something special before we continue

        mov.l    $hal_variant_init,r1

        jsr      @r1

         nop

        # Platform initialization

        mov.l    $hal_platform_init,r1

        jsr      @r1

         nop

        # call c++ constructors

        mov.l    $cyg_hal_invoke_constructors,r1

        jsr      @r1

         nop

#ifdef CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS

        mov.l    $initialize_stub,r1

        jsr      @r1

         nop

#endif

#if defined(CYGDBG_HAL_DEBUG_GDB_CTRLC_SUPPORT) \

    || defined(CYGDBG_HAL_DEBUG_GDB_BREAK_SUPPORT)

        mov.l    $hal_ctrlc_isr_init,r1

        jsr      @r1

         nop

#endif

        mov.l    $cyg_start,r1

        jsr      @r1

         nop

9:

        bra      9b                     ! if we return, loop

         nop

        .align  2

        SYM_PTR_REF(_bss_start)

        SYM_PTR_REF(_bss_end)

        SYM_PTR_REF(startup_stack)

        SYM_PTR_REF(cyg_hal_invoke_constructors)

        SYM_PTR_REF(cyg_var_enable_caches)

        SYM_PTR_REF(hal_variant_init)

        SYM_PTR_REF(hal_platform_init)

        SYM_PTR_REF(cyg_start)

#ifdef CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS

        SYM_PTR_REF(initialize_stub)

#endif

#if defined(CYGDBG_HAL_DEBUG_GDB_CTRLC_SUPPORT) \

    || defined(CYGDBG_HAL_DEBUG_GDB_BREAK_SUPPORT)

        SYM_PTR_REF(hal_ctrlc_isr_init)

#endif

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

# Interrupt vector tables.

# These tables contain the isr, data and object pointers used to deliver

# interrupts to user code.

        .data

        .extern CYG_LABEL_DEFN(hal_default_isr)

#ifdef CYGIMP_HAL_COMMON_INTERRUPTS_CHAIN

#define CYG_ISR_TABLE_SIZE    1

#else

#define CYG_ISR_TABLE_SIZE    CYGNUM_HAL_ISR_COUNT

#endif

SYM_DEF(hal_interrupt_handlers)

        .rept   CYG_ISR_TABLE_SIZE

        .long   CYG_LABEL_DEFN(hal_default_isr)

        .endr

SYM_DEF(hal_interrupt_data)

        .rept   CYG_ISR_TABLE_SIZE

        .long   0

        .endr

SYM_DEF(hal_interrupt_objects)

        .rept   CYG_ISR_TABLE_SIZE

        .long   0

        .endr

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

## Temporary interrupt stack

        .section ".bss"

#ifdef CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK

        .balign 16

SYM_DEF(cyg_interrupt_stack_base)

        .rept CYGNUM_HAL_COMMON_INTERRUPTS_STACK_SIZE

        .byte 0

        .endr

        .balign 16

        .global _cyg_interrupt_stack

SYM_DEF(cyg_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

SYM_DEF(startup_stack_base)

        .rept   STARTUP_STACK_SIZE

        .byte 0

        .endr

        .balign 16

SYM_DEF(startup_stack)

        .long   0,0,0,0

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

# end of vectors.S