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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 c490b93..0000000 --- a/arch/v850/kernel/head.S +++ /dev/null @@ -1,128 +0,0 @@ -/* - * arch/v850/kernel/head.S -- Lowest-level startup code - * - * Copyright (C) 2001,02,03 NEC Electronics Corporation - * Copyright (C) 2001,02,03 Miles Bader <miles@gnu.org> - * - * This file is subject to the terms and conditions of the GNU General - * Public License. See the file COPYING in the main directory of this - * archive for more details. - * - * Written by Miles Bader <miles@gnu.org> - */ - -#include <asm/clinkage.h> -#include <asm/current.h> -#include <asm/entry.h> -#include <asm/thread_info.h> -#include <asm/irq.h> - - -/* Make a slightly more convenient alias for C_SYMBOL_NAME. */ -#define CSYM C_SYMBOL_NAME - - - .text - - // Define `mach_early_init' as a weak symbol - .global CSYM(mach_early_init) - .weak CSYM(mach_early_init) - -C_ENTRY(start): - // Make sure interrupts are turned off, just in case - di - -#ifdef CONFIG_RESET_GUARD - // See if we got here via an unexpected reset - ld.w RESET_GUARD, r19 // Check current value of reset guard - mov RESET_GUARD_ACTIVE, r20 - cmp r19, r20 - bne 1f // Guard was not active - - // If we get here, the reset guard was active. Load up some - // interesting values as arguments, and jump to the handler. - st.w r0, RESET_GUARD // Allow further resets to succeed - mov lp, r6 // Arg 0: return address - ld.b KM, r7 // Arg 1: kernel mode - mov sp, r9 // Arg 3: stack pointer - ld.w KSP, r19 // maybe switch to kernel stack - cmp r7, r0 // see if already in kernel mode - cmov z, r19, sp, sp // and switch to kernel stack if not - GET_CURRENT_TASK(r8) // Arg 2: task pointer - jr CSYM(unexpected_reset) - -1: st.w r20, RESET_GUARD // Turn on reset guard -#endif /* CONFIG_RESET_GUARD */ - - // Setup a temporary stack for doing pre-initialization function calls. - // - // We can't use the initial kernel stack, because (1) it may be - // located in memory we're not allowed to touch, and (2) since - // it's in the data segment, calling memcpy to initialize that - // area from ROM will overwrite memcpy's return address. - mov hilo(CSYM(_init_stack_end) - 4), sp - - // See if there's a platform-specific early-initialization routine - // defined; it's a weak symbol, so it will have an address of zero if - // there's not. - mov hilo(CSYM(mach_early_init)), r6 - cmp r6, r0 - bz 3f - - // There is one, so call it. If this function is written in C, it - // should be very careful -- the stack pointer is valid, but very - // little else is (e.g., bss is not zeroed yet, and initialized data - // hasn't been). - jarl 2f, lp // first figure out return address -2: add 3f - ., lp - jmp [r6] // do call -3: - -#ifdef CONFIG_ROM_KERNEL - // Copy the data area from ROM to RAM - mov hilo(CSYM(_rom_copy_dst_start)), r6 - mov hilo(CSYM(_rom_copy_src_start)), r7 - mov hilo(CSYM(_rom_copy_dst_end)), r8 - sub r6, r8 - jarl CSYM(memcpy), lp -#endif - - // Load the initial thread's stack, and current task pointer (in r16) - mov hilo(CSYM(init_thread_union)), r19 - movea THREAD_SIZE, r19, sp - ld.w TI_TASK[r19], CURRENT_TASK - -#ifdef CONFIG_TIME_BOOTUP - /* This stuff must come after mach_early_init, because interrupts may - not work until after its been called. */ - jarl CSYM(highres_timer_reset), lp - jarl CSYM(highres_timer_start), lp -#endif - - // Kernel stack pointer save location - st.w sp, KSP - - // Assert that we're in `kernel mode' - mov 1, r19 - st.w r19, KM - -#ifdef CONFIG_ZERO_BSS - // Zero bss area, since we can't rely upon any loader to do so - mov hilo(CSYM(_sbss)), r6 - mov r0, r7 - mov hilo(CSYM(_ebss)), r8 - sub r6, r8 - jarl CSYM(memset), lp -#endif - - // What happens if the main kernel function returns (it shouldn't) - mov hilo(CSYM(machine_halt)), lp - - // Start the linux kernel. We use an indirect jump to get extra - // range, because on some platforms this initial startup code - // (and the associated platform-specific code in mach_early_init) - // are located far away from the main kernel, e.g. so that they - // can initialize RAM first and copy the kernel or something. - mov hilo(CSYM(start_kernel)), r12 - jmp [r12] -C_END(start) |