/* * startsis.s * * Start code for the ERC32. * * This is based on the file srt0.s provided with the binary * distribution of the SPARC Instruction Simulator (SIS) found * at ftp://ftp.estec.esa.nl/pub/ws/wsd/erc32. * * $Id$ */ #include #include /* * Unexpected 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 for the time being... */ #define SOFT_TRAP BAD_TRAP .seg "text" PUBLIC(start) .global start SYM(start): start: /* * The trap table has to be the first code in a boot PROM. But because * the Memory Configuration comes up thinking we only have 4K of PROM, we * cannot have a full trap table and still have room left over to * reprogram the Memory Configuration register correctly. This file * uses an abbreviated trap which has every entry which might be used * before RTEMS installs its own trap table. */ PUBLIC(trap_table) SYM(trap_table): RTRAP( 0, SYM(hard_reset) ); ! 00 reset trap BAD_TRAP; ! 01 instruction access ! exception BAD_TRAP; ! 02 illegal instruction BAD_TRAP; ! 03 privileged instruction BAD_TRAP; ! 04 fp disabled TRAP( 5, SYM(window_overflow_trap_handler) ); ! 05 window overflow TRAP( 6, SYM(window_underflow_trap_handler) );! 06 window underflow BAD_TRAP; ! 07 memory address not aligned BAD_TRAP; ! 08 fp exception BAD_TRAP; ! 09 data access exception BAD_TRAP; ! 0A tag overflow BAD_TRAP; ! 0B undefined BAD_TRAP; ! 0C undefined BAD_TRAP; ! 0D undefined BAD_TRAP; ! 0E undefined BAD_TRAP; ! 0F undefined BAD_TRAP; ! 10 undefined /* * ERC32 defined traps */ BAD_TRAP; ! 11 masked errors BAD_TRAP; ! 12 external 1 BAD_TRAP; ! 13 external 2 BAD_TRAP; ! 14 UART A RX/TX BAD_TRAP; ! 15 UART B RX/TX BAD_TRAP; ! 16 correctable memory error BAD_TRAP; ! 17 UART error BAD_TRAP; ! 18 DMA access error BAD_TRAP; ! 19 DMA timeout BAD_TRAP; ! 1A external 3 BAD_TRAP; ! 1B external 4 BAD_TRAP; ! 1C general purpose timer BAD_TRAP; ! 1D real time clock BAD_TRAP; ! 1E external 5 BAD_TRAP; ! 1F watchdog timeout BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 20 - 23 undefined BAD_TRAP; ! 24 cp_disabled BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 25 - 27 undefined BAD_TRAP; ! 28 cp_exception BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 29 - 2B undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 2C - 2F undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 30 - 33 undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 34 - 37 undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 38 - 3B undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 3C - 3F undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 40 - 43 undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 44 - 47 undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 48 - 4B undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 4C - 4F undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 50 - 53 undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 54 - 57 undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 58 - 5B undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 5C - 5F undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 60 - 63 undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 64 - 67 undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 68 - 6B undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 6C - 6F undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 70 - 73 undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 74 - 77 undefined BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 78 - 7B undefined /* This is a sad patch to make sure that we know where the MEC timer control register mirror is so we can stop the timers from an external debugger. It is needed because the control register is write-only. Trap 0x7C cannot occure in ERC32... We also use this location to store the last location of the usable RAM in order not to overwrite the remote debugger with the RTEMS work-space area. */ .global __ERC32_MEC_Timer_Control_Mirror, SYM(rdb_start), SYM(CLOCK_SPEED) SYM(rdb_start): __ERC32_MEC_Timer_Control_Mirror: BAD_TRAP; BAD_TRAP; ! 7C - 7D undefined SYM(CLOCK_SPEED): .word 0x0a, 0, 0, 0 ! 7E (10 MHz default) BAD_TRAP; ! 7F undefined /* * Software traps * * NOTE: At the risk of being redundant... this is not a full * table. The setjmp on the SPARC requires a window flush trap * handler and RTEMS will preserve the entries that were * installed before. */ SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 80 - 82 TRAP( 0x83, SYM(window_flush_trap_handler) ); ! 83 flush windows SW trap SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 84 - 87 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 88 - 8B SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 8C - 8F SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 90 - 93 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 94 - 97 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 98 - 9B SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 9C - 9F SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! A0 - A3 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! A4 - A7 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! A8 - AB SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! AC - AF SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! B0 - B3 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! B4 - B7 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! B8 - BB SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! BC - BF SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! C0 - C3 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! C4 - C7 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! C8 - CB SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! CC - CF SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! D0 - D3 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! D4 - D7 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! D8 - DB SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! DC - DF SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! E0 - E3 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! E4 - E7 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! E8 - EB SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! EC - EF SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! F0 - F3 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! F4 - F7 SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! F8 - FB SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! FC - FF /* * This is the hard reset code. */ #define PSR_INIT 0x10c0 /* Disable traps, set s and ps */ #define WIM_INIT 2 #define STACK_SIZE 16 * 1024 PUBLIC(hard_reset) SYM(hard_reset): set SYM(trap_table), %g1 ! Initialize TBR mov %g1, %tbr set (SYM(rdb_start)), %g6 ! End of work-space area st %sp, [%g6] /* Check if MEC is initialised. If not, this means that we are running on the simulator. Initiate some of the parameters that are done by the boot-prom otherwise. */ set SYM(ERC32_MEC), %g3 ! g3 = base address of peripherals ld [%g3], %g2 set 0xfe080000, %g1 andcc %g1, %g2, %g0 bne 1f set 0x00101000, %g1 ! 2M ROM, 4M RAM ! set the Memory Configuration st %g1, [ %g3 + ERC32_MEC_MEMORY_CONFIGURATION_OFFSET ] set SYM(RAM_END), %sp ! End of work-space area st %sp, [%g6] set SYM(CLOCK_SPEED), %g6 ! Use 14 MHz in simulator set 14, %g1 st %g1, [%g6] /* Common initialisation */ 1: set WIM_INIT, %g1 ! Initialize WIM mov %g1, %wim set PSR_INIT, %g1 wr %g1, 0x20, %psr ! enable traps nop nop nop sethi %hi(stack_space + STACK_SIZE), %g1 or %g1,%lo(stack_space + STACK_SIZE),%g1 ! g1 = top of stack mov %g1, %sp ! Set stack pointer mov %sp, %fp ! Set frame pointer nop /* * Copy the initialized data to RAM * * FROM: _endtext * TO: _data_start * LENGTH: (__bss_start - _data_start) bytes */ sethi %hi(_endtext),%g2 or %g2,%lo(_endtext),%g2 ! g2 = start of initialized data in ROM sethi %hi(_data_start),%g3 or %g3,%lo(_data_start),%g3 ! g3 = start of initialized data in RAM sethi %hi(__bss_start),%g4 or %g4,%lo(__bss_start),%g4 ! g4 = end of initialized data in RAM cmp %g2, %g3 be 1f nop copy_data: ldd [ %g2 ], %g6 std %g6 , [ %g3 ] ! copy this double word add %g3, 8, %g3 ! bump the destination pointer add %g2, 8, %g2 ! bump the source pointer cmp %g3, %g4 ! Is the pointer past the end of dest? bl copy_data nop /* clear the bss */ 1: sethi %hi(_edata),%g2 or %g2,%lo(_edata),%g2 ! g2 = start of bss sethi %hi(_end),%g3 or %g3,%lo(_end),%g3 ! g3 = end of bss mov %g0,%g1 ! so std has two zeros zerobss: std %g0,[%g2] add %g2,8,%g2 cmp %g2,%g3 bleu,a zerobss nop mov %0, %o2 ! environ mov %0, %o1 ! argv mov %0, %o0 ! argc call SYM(boot_card) sub %sp, 0x60, %sp ! room for boot_card to save args nop PUBLIC(BSP_fatal_return) SYM(BSP_fatal_return): ta 0 ! Halt if _main returns ... nop /* * There does not seem to be a way to get this aligned AND * in the BSS. */ .align 32 .comm stack_space, STACK_SIZE /* end of file */