libc/libgloss/mt/startup-64-001.S

379 lines
8.8 KiB
ArmAsm

/*
* $Header$
*
* interrupt_vectors.s -- the interrupt handler jump table.
*
*
* There are a total of 32 interrupt vector possible, however, only
* 11 of those are currently used (the others are reserved). The
* order of vectors is as follows:
*
* 1. Boot Vector. Vector for power-on/reset.
* 2. Software Vector. Vector for handling the SI instruction (an
* explicit interrupt caused by software).
* 3. Break Vector. Vector for handling the Break instruction.
* 4. Device 0 Vector. Service vector for device zero.
* 5. Device 1 Vector. Service vector for device one.
* 6. Device 2 Vector. Service vector for device two.
* 7. Device 3 Vector. Service vector for device three.
* 8. Device 4 Vector. Service vector for device four.
* 9. Device 5 Vector. Service vector for device five.
* 10. Device 6 Vector. Service vector for device six.
* 11. Device 7 Vector. Service vector for device seven.
*
* The rest of the interrupt vectors are reserved for future use.
*
*
* Each jump table entry consists of the following two instructions:
*
* jmp Label ; Label as appropriate
* nop ; implemented as or r0,r0,r0
*
* The following labels are reserved for the vectors named above,
* respectively:
*
* _BOOTIVEC, _SOFTIVEC, _BRKIVEC, _DEV0IVEC, _DEV1IVEC, _DEV2IVEC,
* _DEV3IVEC, _DEV4IVEC, _DEV5IVEC, _DEV6IVEC, _DEV7IVEC
*
*
* 26Sep01 (DJK) The memory map is changed and the device interrupts are
* now memory-mapped.
*
* 10Oct01 (DJK) The memory map is finalized and the first 4K of address
* space is now reserved for memory-mapped I/O devices.
* (There is over 2K unused, reserved space in this area.)
*
* 27Jul02 (DJK) Fixed the address for the interrupt mask register. Old
* documentation stated the port address as 0x140, but
* the implementation uses 0x13c.
*
* 30Jul02 (DJK) Added support for printf. This only supports output to
* stderr and stdout. Using the message box interface,
* a (newly defined) message or series of messages is
* passed to the controller to output bytes as text to
* the debug console. These messages are constructed in
* the interrupt handler for the SI instruction.
* With this implementation, the user is unable to
* utilize the message box interface in applications as
* specialized interrupt handlers for the external
* interrupts are necessary.
*
*
*
* Copyright (c) 2001, 2002, 2003, 2004 Morpho Technologies, Inc.
*
*/
.section .startup, "a", @progbits
.global __boot_start
_INTERRUPT_VECTOR_TABLE:
__boot_start:
jmp _BOOTIVEC ; Boot vector
or r0, r0, r0
jmp _SOFTIVEC ; Vector for SI instruction
or r0,r0,r0
jmp _BRKIVEC ; Vector for Break instruction
or r0,r0,r0
; This is the memory-mapped I/O region.
; Hardware Interrupt Registers
.org 0x100
.global _DEV0_INTERRUPT_REG
_DEV0_INTERRUPT_REG:
.word 0x00000000
.global _DEV1_INTERRUPT_REG
_DEV1_INTERRUPT_REG:
.word 0x00000000
.global _DEV2_INTERRUPT_REG
_DEV2_INTERRUPT_REG:
.word 0x00000000
.global _DEV3_INTERRUPT_REG
_DEV3_INTERRUPT_REG:
.word 0x00000000
.global _DEV4_INTERRUPT_REG
_DEV4_INTERRUPT_REG:
.word 0x00000000
.global _DEV5_INTERRUPT_REG
_DEV5_INTERRUPT_REG:
.word 0x00000000
.global _DEV6_INTERRUPT_REG
_DEV6_INTERRUPT_REG:
.word 0x00000000
.global _DEV7_INTERRUPT_REG
_DEV7_INTERRUPT_REG:
.word 0x00000000
; 60 bytes minus eight registers (four bytes per register)
.fill (60 - 8 * 4)
.global _INTERRUPT_MASK_REG
_INTERRUPT_MASK_REG:
.word 0x00000000
; 256 bytes minus sixteen registers (four bytes per register)
.fill (256 - 16 * 4)
.org 0x200
; MorphoSys Decoder Registers
.global _MS_DEC_AUTO_INCREMENT_REG
_MS_DEC_AUTO_INCREMENT_REG:
.word 0x00000000
.global _MS_DEC_SKIP_FACTOR_REG
_MS_DEC_SKIP_FACTOR_REG:
.word 0x00000000
.global _MS_DEC_CUSTOM_PERMUTATION_REG
_MS_DEC_CUSTOM_PERMUTATION_REG:
.word 0x00000000
.global _MS_DEC_CONTEXT_BASE_REG
_MS_DEC_CONTEXT_BASE_REG:
.word 0x00000000
.global _MS_DEC_LOOKUP_TABLE_BASE_REG
_MS_DEC_LOOKUP_TABLE_BASE_REG:
.word 0x00000000
.global _MS_CIRCULAR_BUFFER_END_REG
_MS_CIRCULAR_BUFFER_END_REG:
.word (__FRAME_BUFFER_END)
.global _MS_CIRCULAR_BUFFER_SIZE_REG
_MS_CIRCULAR_BUFFER_SIZE_REG:
.word __FRAME_BUFFER_SIZE
.global _MS_DATA_BLOCK_END_REG
_MS_DATA_BLOCK_END_REG:
.word 0x00000000
.global _MS_DATA_BLOCK_SIZE_REG
_MS_DATA_BLOCK_SIZE_REG:
.word 0x00000000
; 256 bytes minus nine registers (four bytes per register)
.fill (256 - 9 * 4)
.org 0x300
; Debug Registers
.global _DEBUG_HALT_REG
_DEBUG_HALT_REG:
.word 0x00000000
.global _DEBUG_BREAK_REG
_DEBUG_BREAK_REG:
.word 0x00000000
.global _DEBUG_HW_RESERVED0_REG
_DEBUG_HW_RESERVED0_REG:
.word 0x00000000
.global _DEBUG_HW_RESERVED1_REG
_DEBUG_HW_RESERVED1_REG:
.word 0x00000000
.global _DEBUG_HW_RESERVED2_REG
_DEBUG_HW_RESERVED2_REG:
.word 0x00000000
.global _DEBUG_HW_RESERVED3_REG
_DEBUG_HW_RESERVED3_REG:
.word 0x00000000
.global _DEBUG_HW_RESERVED4_REG
_DEBUG_HW_RESERVED4_REG:
.word 0x00000000
.global _DEBUG_SW_SYSREQ_REG
_DEBUG_SW_SYSREQ_REG:
.word 0x00000000
; 256 bytes minus eight registers (four bytes per register)
.fill (256 - 8 * 4)
.org 0x400
; Sequence Generator Registers
_SEQ_GEN_REGS:
.fill 256
.org 0x500
_RESERVED_SEQ_GEN_REGS:
.fill 256
.org 0x600
.global _TIMER0_VAL_REG
_TIMER0_VAL_REG:
.word 0x00000000
.global _TIMER0_CTRL_REG
_TIMER0_CTRL_REG:
.word 0x00000000
.global _TIMER1_VAL_REG
_TIMER1_VAL_REG:
.word 0x00000000
.global _TIMER1_CTRL_REG
_TIMER1_CTRL_REG:
.word 0x00000000
.global _TIMER2_VAL_REG
_TIMER2_VAL_REG:
.word 0x00000000
.global _TIMER2_CTRL_REG
_TIMER2_CTRL_REG:
.word 0x00000000
; 256 bytes minus six registers (four bytes per register)
.fill (256 - 6 * 4)
.org 0x700
.global _OUTPUT0_CONTROL
_OUTPUT0_CONTROL:
.word 0x00000000
.global _OUTPUT1_CONTROL
_OUTPUT1_CONTROL:
.word 0x00000000
.global _OUTPUT2_CONTROL
_OUTPUT2_CONTROL:
.word 0x00000000
.global _OUTPUT3_CONTROL
_OUTPUT3_CONTROL:
.word 0x00000000
.global _OUTPUT4_CONTROL
_OUTPUT4_CONTROL:
.word 0x00000000
.global _OUTPUT5_CONTROL
_OUTPUT5_CONTROL:
.word 0x00000000
.global _OUTPUT6_CONTROL
_OUTPUT6_CONTROL:
.word 0x00000000
.global _OUTPUT7_CONTROL
_OUTPUT7_CONTROL:
.word 0x00000000
; 256 bytes minus eight registers (four bytes per register)
.fill (256 - 8 * 4)
.org 0x800
; Reserved memory-mapped space.
.fill (0x1000 - 0x800)
.text
.equ SI_IOPORT_ADR, _DEBUG_SW_SYSREQ_REG
.equ SI_IOPORT_BIT, 0x1
.equ BRK_IOPORT_ADR, _DEBUG_BREAK_REG
.equ BRK_IOPORT_BIT, 0x1
.global _BOOTIVEC
_BOOTIVEC:
; Initialize the interrupt controller's interrupt vector registers
; for devices zero through seven.
ldui r1, #%hi16(_IVEC_DEFAULT)
ori r1, r1, #%lo16(_IVEC_DEFAULT)
stw r1, r0, #%lo16(_DEV0_INTERRUPT_REG)
stw r1, r0, #%lo16(_DEV1_INTERRUPT_REG)
stw r1, r0, #%lo16(_DEV2_INTERRUPT_REG)
stw r1, r0, #%lo16(_DEV3_INTERRUPT_REG)
stw r1, r0, #%lo16(_DEV4_INTERRUPT_REG)
stw r1, r0, #%lo16(_DEV5_INTERRUPT_REG)
stw r1, r0, #%lo16(_DEV6_INTERRUPT_REG)
stw r1, r0, #%lo16(_DEV7_INTERRUPT_REG)
; Jump to the beginning of the application and enable interrupts.
jmp _start
ei
; Handler for the SI instruction. To perform a system call, the
; C model uses a trapping mechanism which executes an SI instruction.
; The Morpho Technologies simulator simply performs a branch to
; this vector to simulate the SI instruction (this is as the hardware
; behaves). In order to trigger the simulator that a system call
; is needed, a write into the I/O register at address $40005 to
; set bit #2 (0x4) is necessary.
;
; The above address has been changed to 0x31C and the bit number
; is zero. (The manifest constants have been changed to reflect this.)
;
.global _SOFTIVEC
_SOFTIVEC:
; Build a frame to save registers.
subi sp, sp, #$8
stw r9, sp, #$4
ldui r9, #%hi16(SI_IOPORT_ADR)
stw r10, sp, #$0
ori r9, r9, #%lo16(SI_IOPORT_ADR)
ori r10, r0, #SI_IOPORT_BIT
stw r10, r9, #$0
; SYS_call is handled by simulator here...
or r0, r0, r0
ldw r10, sp, #$0
or r0, r0, r0
ldw r9, sp, #$4
reti r14
addi sp, sp, #$8
.global _BRKIVEC
_BRKIVEC:
; Build a frame to save registers.
subi sp, sp, #$8
stw r9, sp, #$4
ldui r9, #%hi16(BRK_IOPORT_ADR)
stw r10, sp, #$0
ori r9, r9, #%lo16(BRK_IOPORT_ADR)
ori r10, r0, #BRK_IOPORT_BIT
stw r10, r9, #$0
or r0, r0, r0
ldw r10, sp, #$0
subi r15, r15, #$4 ; Backup to address of break
ldw r9, sp, #$4
reti r15
addi sp, sp, #$8
.global _IVEC_DEFAULT
_IVEC_DEFAULT:
reti r15
or r0, r0, r0