diff options
Diffstat (limited to 'arch/v850/kernel/head.S')
| -rw-r--r-- | arch/v850/kernel/head.S | 128 |
1 files changed, 0 insertions, 128 deletions
diff --git a/arch/v850/kernel/head.S b/arch/v850/kernel/head.S deleted file mode 100644 index c490b937ef14..000000000000 --- a/arch/v850/kernel/head.S +++ /dev/null | |||
| @@ -1,128 +0,0 @@ | |||
| 1 | /* | ||
| 2 | * arch/v850/kernel/head.S -- Lowest-level startup code | ||
| 3 | * | ||
| 4 | * Copyright (C) 2001,02,03 NEC Electronics Corporation | ||
| 5 | * Copyright (C) 2001,02,03 Miles Bader <miles@gnu.org> | ||
| 6 | * | ||
| 7 | * This file is subject to the terms and conditions of the GNU General | ||
| 8 | * Public License. See the file COPYING in the main directory of this | ||
| 9 | * archive for more details. | ||
| 10 | * | ||
| 11 | * Written by Miles Bader <miles@gnu.org> | ||
| 12 | */ | ||
| 13 | |||
| 14 | #include <asm/clinkage.h> | ||
| 15 | #include <asm/current.h> | ||
| 16 | #include <asm/entry.h> | ||
| 17 | #include <asm/thread_info.h> | ||
| 18 | #include <asm/irq.h> | ||
| 19 | |||
| 20 | |||
| 21 | /* Make a slightly more convenient alias for C_SYMBOL_NAME. */ | ||
| 22 | #define CSYM C_SYMBOL_NAME | ||
| 23 | |||
| 24 | |||
| 25 | .text | ||
| 26 | |||
| 27 | // Define `mach_early_init' as a weak symbol | ||
| 28 | .global CSYM(mach_early_init) | ||
| 29 | .weak CSYM(mach_early_init) | ||
| 30 | |||
| 31 | C_ENTRY(start): | ||
| 32 | // Make sure interrupts are turned off, just in case | ||
| 33 | di | ||
| 34 | |||
| 35 | #ifdef CONFIG_RESET_GUARD | ||
| 36 | // See if we got here via an unexpected reset | ||
| 37 | ld.w RESET_GUARD, r19 // Check current value of reset guard | ||
| 38 | mov RESET_GUARD_ACTIVE, r20 | ||
| 39 | cmp r19, r20 | ||
| 40 | bne 1f // Guard was not active | ||
| 41 | |||
| 42 | // If we get here, the reset guard was active. Load up some | ||
| 43 | // interesting values as arguments, and jump to the handler. | ||
| 44 | st.w r0, RESET_GUARD // Allow further resets to succeed | ||
| 45 | mov lp, r6 // Arg 0: return address | ||
| 46 | ld.b KM, r7 // Arg 1: kernel mode | ||
| 47 | mov sp, r9 // Arg 3: stack pointer | ||
| 48 | ld.w KSP, r19 // maybe switch to kernel stack | ||
| 49 | cmp r7, r0 // see if already in kernel mode | ||
| 50 | cmov z, r19, sp, sp // and switch to kernel stack if not | ||
| 51 | GET_CURRENT_TASK(r8) // Arg 2: task pointer | ||
| 52 | jr CSYM(unexpected_reset) | ||
| 53 | |||
| 54 | 1: st.w r20, RESET_GUARD // Turn on reset guard | ||
| 55 | #endif /* CONFIG_RESET_GUARD */ | ||
| 56 | |||
| 57 | // Setup a temporary stack for doing pre-initialization function calls. | ||
| 58 | // | ||
| 59 | // We can't use the initial kernel stack, because (1) it may be | ||
| 60 | // located in memory we're not allowed to touch, and (2) since | ||
| 61 | // it's in the data segment, calling memcpy to initialize that | ||
| 62 | // area from ROM will overwrite memcpy's return address. | ||
| 63 | mov hilo(CSYM(_init_stack_end) - 4), sp | ||
| 64 | |||
| 65 | // See if there's a platform-specific early-initialization routine | ||
| 66 | // defined; it's a weak symbol, so it will have an address of zero if | ||
| 67 | // there's not. | ||
| 68 | mov hilo(CSYM(mach_early_init)), r6 | ||
| 69 | cmp r6, r0 | ||
| 70 | bz 3f | ||
| 71 | |||
| 72 | // There is one, so call it. If this function is written in C, it | ||
| 73 | // should be very careful -- the stack pointer is valid, but very | ||
| 74 | // little else is (e.g., bss is not zeroed yet, and initialized data | ||
| 75 | // hasn't been). | ||
| 76 | jarl 2f, lp // first figure out return address | ||
| 77 | 2: add 3f - ., lp | ||
| 78 | jmp [r6] // do call | ||
| 79 | 3: | ||
| 80 | |||
| 81 | #ifdef CONFIG_ROM_KERNEL | ||
| 82 | // Copy the data area from ROM to RAM | ||
| 83 | mov hilo(CSYM(_rom_copy_dst_start)), r6 | ||
| 84 | mov hilo(CSYM(_rom_copy_src_start)), r7 | ||
| 85 | mov hilo(CSYM(_rom_copy_dst_end)), r8 | ||
| 86 | sub r6, r8 | ||
| 87 | jarl CSYM(memcpy), lp | ||
| 88 | #endif | ||
| 89 | |||
| 90 | // Load the initial thread's stack, and current task pointer (in r16) | ||
| 91 | mov hilo(CSYM(init_thread_union)), r19 | ||
| 92 | movea THREAD_SIZE, r19, sp | ||
| 93 | ld.w TI_TASK[r19], CURRENT_TASK | ||
| 94 | |||
| 95 | #ifdef CONFIG_TIME_BOOTUP | ||
| 96 | /* This stuff must come after mach_early_init, because interrupts may | ||
| 97 | not work until after its been called. */ | ||
| 98 | jarl CSYM(highres_timer_reset), lp | ||
| 99 | jarl CSYM(highres_timer_start), lp | ||
| 100 | #endif | ||
| 101 | |||
| 102 | // Kernel stack pointer save location | ||
| 103 | st.w sp, KSP | ||
| 104 | |||
| 105 | // Assert that we're in `kernel mode' | ||
| 106 | mov 1, r19 | ||
| 107 | st.w r19, KM | ||
| 108 | |||
| 109 | #ifdef CONFIG_ZERO_BSS | ||
| 110 | // Zero bss area, since we can't rely upon any loader to do so | ||
| 111 | mov hilo(CSYM(_sbss)), r6 | ||
| 112 | mov r0, r7 | ||
| 113 | mov hilo(CSYM(_ebss)), r8 | ||
| 114 | sub r6, r8 | ||
| 115 | jarl CSYM(memset), lp | ||
| 116 | #endif | ||
| 117 | |||
| 118 | // What happens if the main kernel function returns (it shouldn't) | ||
| 119 | mov hilo(CSYM(machine_halt)), lp | ||
| 120 | |||
| 121 | // Start the linux kernel. We use an indirect jump to get extra | ||
| 122 | // range, because on some platforms this initial startup code | ||
| 123 | // (and the associated platform-specific code in mach_early_init) | ||
| 124 | // are located far away from the main kernel, e.g. so that they | ||
| 125 | // can initialize RAM first and copy the kernel or something. | ||
| 126 | mov hilo(CSYM(start_kernel)), r12 | ||
| 127 | jmp [r12] | ||
| 128 | C_END(start) | ||