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Diffstat (limited to 'libgloss/ms1/crt0-16-002.S')
| -rw-r--r-- | libgloss/ms1/crt0-16-002.S | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/libgloss/ms1/crt0-16-002.S b/libgloss/ms1/crt0-16-002.S new file mode 100644 index 0000000..ac2727e --- /dev/null +++ b/libgloss/ms1/crt0-16-002.S @@ -0,0 +1,111 @@ +; crt0_2.s - Startup code for the mrisc1. This code initializes the C +; run-time model. +; +; Copyright 2001, 2002, 2003, 2004 Free Software Foundation, Inc. +; +; The authors hereby grant permission to use, copy, modify, distribute, +; and license this software and its documentation for any purpose, provided +; that existing copyright notices are retained in all copies and that this +; notice is included verbatim in any distributions. No written agreement, +; license, or royalty fee is required for any of the authorized uses. +; Modifications to this software may be copyrighted by their authors +; and need not follow the licensing terms described here, provided that +; the new terms are clearly indicated on the first page of each file where +; they apply. +; + + ; Create a label for the start of the eh_frame section. + .section .eh_frame +__eh_frame_begin: + + .text + .global _start +_start: + ;; Initialize the stack pointer + ldui sp, #%hi16(__stack) + addui sp, sp, #%lo16(__stack) + or fp, sp, sp + ;; Zero the bss space + ldui r9, #%hi16(__bss_start) + addui r9, r9, #%lo16(__bss_start) + ldui r10, #%hi16(__bss_end) + addui r10, r10, #%lo16(__bss_end) + or r0, r0, r0 + brle r10, r9, .Lnext1 + or r0, r0, r0 +.Lcpy0: + stw r0, r9, #0 + addi r9, r9, #4 + or r0, r0, r0 ; nop + brle r9, r10, .Lcpy0 + or r0, r0, r0 ; nop + +.Lnext1: + ;; Copy data from ROM to Frame Buffer (on-chip memory) + ldui r9, #%hi16(_fbdata_start) + ori r9, r9, #%lo16(_fbdata_start) + ldui r10, #%hi16(_fbdata_end) + ori r10, r10, #%lo16(_fbdata_end) + ldui r11, #%hi16(_fbdata_vma) + brle r10, r9, .Lnext2 + ori r11, r11, #%lo16(_fbdata_vma) +.Lcpy1: + ldw r5, r9, #$0 + addi r9, r9, #$4 + stw r5, r11, #$0 + brlt r9, r10, .Lcpy1 + addi r11, r11, #$4 + +.Lnext2: + ;; Zero the frame buffer bss section + ldui r9, #%hi16(_fbbss_start) + ori r9, r9, #%lo16(_fbbss_start) + ldui r10, #%hi16(_fbbss_end) + ori r10, r10, #%lo16(_fbbss_end) + or r0, r0, r0 + brle r10, r9, .Lnext3 + or r0, r0, r0 +.Lcpy2: + stw r0, r9, #$0 + addi r9, r9, #$4 + or r0, r0, r0 + brle r9, r10, .Lcpy2 + or r0, r0, r0 + +.Lnext3: + ;; Call global and static constructors + ldui r10, #%hi16(_init) + ori r10, r10, #%lo16(_init) + or r0, r0, r0 ; nop + jal r14, r10 + or r0, r0, r0 ; nop + + ;; Call main + ldui r10, #%hi16(main) + ori r10, r10, #%lo16(main) + or r0, r0, r0 ; nop + jal r14, r10 + or r0, r0, r0 ; nop + + ;; DJK - Added 12Nov01. Pass main's return value to exit. + or r1, r11, r0 + + ;; Jump to exit + ldui r10, #%hi16(exit) + ori r10, r10, #%lo16(exit) + or r0, r0, r0 ; nop + jal r14, r10 + or r0, r0, r0 ; nop + + ;; Exit does not return, however, this code is to catch an + ;; error if it does. Set the processor into sleep mode. + ori r1, r0, #$1 + stw r1, r0, #%lo16(_DEBUG_HALT_REG) + or r0, r0, r0 + or r0, r0, r0 + or r0, r0, r0 + or r0, r0, r0 + or r0, r0, r0 +.Lend: + jmp .Lend + or r0, r0, r0 |