| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107 |
- /*
- * ARC CPU startup Code
- *
- * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * Vineetg: Dec 2007
- * -Check if we are running on Simulator or on real hardware
- * to skip certain things during boot on simulator
- */
- #include <asm/asm-offsets.h>
- #include <asm/entry.h>
- #include <linux/linkage.h>
- #include <asm/arcregs.h>
- .cpu A7
- .section .init.text, "ax",@progbits
- .type stext, @function
- .globl stext
- stext:
- ;-------------------------------------------------------------------
- ; Don't clobber r0-r2 yet. It might have bootloader provided info
- ;-------------------------------------------------------------------
- sr @_int_vec_base_lds, [AUX_INTR_VEC_BASE]
- #ifdef CONFIG_SMP
- ; Ensure Boot (Master) proceeds. Others wait in platform dependent way
- ; IDENTITY Reg [ 3 2 1 0 ]
- ; (cpu-id) ^^^ => Zero for UP ARC700
- ; => #Core-ID if SMP (Master 0)
- ; Note that non-boot CPUs might not land here if halt-on-reset and
- ; instead breath life from @first_lines_of_secondary, but we still
- ; need to make sure only boot cpu takes this path.
- GET_CPU_ID r5
- cmp r5, 0
- mov.ne r0, r5
- jne arc_platform_smp_wait_to_boot
- #endif
- ; Clear BSS before updating any globals
- ; XXX: use ZOL here
- mov r5, __bss_start
- mov r6, __bss_stop
- 1:
- st.ab 0, [r5,4]
- brlt r5, r6, 1b
- ; Uboot - kernel ABI
- ; r0 = [0] No uboot interaction, [1] cmdline in r2, [2] DTB in r2
- ; r1 = magic number (board identity, unused as of now
- ; r2 = pointer to uboot provided cmdline or external DTB in mem
- ; These are handled later in setup_arch()
- st r0, [@uboot_tag]
- st r2, [@uboot_arg]
- ; Identify if running on ISS vs Silicon
- ; IDENTITY Reg [ 3 2 1 0 ]
- ; (chip-id) ^^^^^ ==> 0xffff for ISS
- lr r0, [identity]
- lsr r3, r0, 16
- cmp r3, 0xffff
- mov.z r4, 0
- mov.nz r4, 1
- st r4, [@running_on_hw]
- ; setup "current" tsk and optionally cache it in dedicated r25
- mov r9, @init_task
- SET_CURR_TASK_ON_CPU r9, r0 ; r9 = tsk, r0 = scratch
- ; setup stack (fp, sp)
- mov fp, 0
- ; tsk->thread_info is really a PAGE, whose bottom hoists stack
- GET_TSK_STACK_BASE r9, sp ; r9 = tsk, sp = stack base(output)
- j start_kernel ; "C" entry point
- #ifdef CONFIG_SMP
- ;----------------------------------------------------------------
- ; First lines of code run by secondary before jumping to 'C'
- ;----------------------------------------------------------------
- .section .text, "ax",@progbits
- .type first_lines_of_secondary, @function
- .globl first_lines_of_secondary
- first_lines_of_secondary:
- sr @_int_vec_base_lds, [AUX_INTR_VEC_BASE]
- ; setup per-cpu idle task as "current" on this CPU
- ld r0, [@secondary_idle_tsk]
- SET_CURR_TASK_ON_CPU r0, r1
- ; setup stack (fp, sp)
- mov fp, 0
- ; set it's stack base to tsk->thread_info bottom
- GET_TSK_STACK_BASE r0, sp
- j start_kernel_secondary
- #endif
|
