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Diffstat (limited to 'libgloss/sparc_leon/locore.S')
| -rw-r--r-- | libgloss/sparc_leon/locore.S | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/libgloss/sparc_leon/locore.S b/libgloss/sparc_leon/locore.S new file mode 100644 index 000000000..011711bc0 --- /dev/null +++ b/libgloss/sparc_leon/locore.S @@ -0,0 +1,170 @@ +/* + * Copyright (c) 2011 Aeroflex Gaisler + * + * BSD license: + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + + +/* The traptable has to be the first code in a boot PROM. */ + +#include <asm-leon/head.h> + +#define TRAP(H) mov %psr, %l0; sethi %hi(H), %l4; jmp %l4+%lo(H); nop; +#define TRAPL(H) nop; sethi %hi(H), %g1; jmp %g1+%lo(H); nop; +#define TRAP_ENTRY(H) rd %psr, %l0; b H; rd %wim, %l3; nop; + +#define WIM_INIT 2 +#ifdef _SOFT_FLOAT +#define PSR_INIT 0x0e0 +#else +#define PSR_INIT 0x10e0 +#endif + +#define NUMREGWINDOWS 8 + +/* Unexcpected trap will halt the processor by forcing it to error state */ +#define BAD_TRAP ta 0; nop; nop; nop; + +/* Software trap. Treat as BAD_TRAP */ +#define SOFT_TRAP BAD_TRAP + + .seg "text" + .global _trap_table, start, _start, cpuinit, leonbare_irq_entry, _hardreset + .global _window_overflow, _window_underflow, _flush_windows, _fpdis_enable + /*.global _nwindows, _leon_version, _nwindows_min1*/ + + +! +! Startup code for standalone system. Wash IU and FPU (if present) registers. +! The registers have to be written to initiate the parity bits. +! + .section .text + /* ------- */ + .weak _hardreset + .set _hardreset,_hardreset_libgloss + /* ------- */ + + .global _hardreset_custom_weak, _hardreset_real, _cleanregs_custom_weak, _hardreset_custom_svt_weak + +_hardreset_real: + nop +_hardreset_libgloss: + set _hardreset_custom_weak, %g1 ! possible mkprom init code here, default links to dummy _hardreset_custom_dummy + call %g1 + nop + + set _trap_table, %g1 ! Initialize TBR + mov %g1, %tbr + + set _hardreset_custom_svt_weak, %g1 ! give mkprom svt chance to reset tbr + call %g1 + nop + + set _cleanregs_custom_weak, %g1 + call %g1 + nop + +#ifdef _FLAT + mov %g0, %wim +#else +/* ! assume that %sp is correct use cwp of psr to set the next window as invalid + mov %psr, %g2 ! extract cwp + and 0x1f, %g2,%g2 + set 0x1, %g3 + sll %g3,%g2,%g3 ! the bit mask for cwp + + sll %g3, 1, %g4 ! rotate one to left + sethi %hi(_nwindows_min1), %g5 ! NWINDOWS-1 + ld [%g5+%lo(_nwindows_min1)], %g5 + srl %g3, %g5, %g5 + or %g5, %g4, %g5 + mov %g5, %wim + nop; nop; nop */ +#endif + +/* + mov %psr, %g2 + set 0x202, %g3 + sll %g3, %g2, %g2 + mov %g2, %wim + nop; nop; nop +1: +*/ + ! ------------------------------- + ! only cpu 0 initializes +/* mov %psr, %g5 + srl %g5, 24, %g5 + and %g5, 3, %g5 + subcc %g5, 3, %g0 ! leon2: 0 or 2, leon3: 3 + bne callcpuinit + nop +*/ + + rd %asr17,%g5 + srl %g5,28,%g5 + cmp %g5,%g0 + bne slavego + nop + +callcpuinit: + call cpuinit + nop + + call pnpinit + nop + +slavego: + ! ------------------------------- + + sub %sp, 0x40, %sp ! room for main to save args + call _start + nop + + mov 1, %g1 + ta 0 ! Halt if _main would return ... + nop + + .global _fpdis,_fpdis_svt +_fpdis_svt: +_fpdis: + set 0x1000, %l4 + andcc %l0, %l4, %l3 + bne,a 4f + andn %l0, %l4, %l0 + ta 0 +4: + mov %l0, %psr ! restore %psr + nop; nop; nop + jmp %l2 ! Jump to nPC + rett %l2 + 4 + + +/* +!'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' + .section .bss + .global _nwindows, _leon_version, _nwindows_min1 +_nwindows: + .word 8 +_nwindows_min1: + .word 7 +_leon_version: + .word 3 +*/ |