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* 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.
* Copyright (C) 1994, 1995 Waldorf Electronics
* Written by Ralf Baechle and Andreas Busse
* Copyright (C) 1994 - 99, 2003, 06 Ralf Baechle
* Copyright (C) 1996 Paul M. Antoine
* Modified for DECStation and hence R3000 support by Paul M. Antoine
* Further modifications by David S. Miller and Harald Koerfgen
* Copyright (C) 1999 Silicon Graphics, Inc.
* Kevin Kissell, and Carsten Langgaard,
* Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved.
#include <linux/init.h>
#include <linux/threads.h>
#include <asm/addrspace.h>
#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/irqflags.h>
#include <asm/regdef.h>
#include <asm/pgtable-bits.h>
#include <asm/mipsregs.h>
#include <asm/stackframe.h>
#include <kernel-entry-init.h>
* For the moment disable interrupts, mark the kernel mode and
* set ST0_KX so that the CPU does not spit fire when using
* 64-bit addresses. A full initialization of the CPU's status
* register is done later in per_cpu_trap_init().
.macro setup_c0_status set clr
.set push
* For SMTC, we need to set privilege and disable interrupts only for
* the current TC, using the TCStatus register.
mfc0 t0, CP0_TCSTATUS
/* Fortunately CU 0 is in the same place in both registers */
/* Set TCU0, TMX, TKSU (for later inversion) and IXMT */
li t1, ST0_CU0 | 0x08001c00
or t0, t1
/* Clear TKSU, leave IXMT */
xori t0, 0x00001800
mtc0 t0, CP0_TCSTATUS
/* We need to leave the global IE bit set, but clear EXL...*/
mfc0 t0, CP0_STATUS
or t0, ST0_CU0 | ST0_EXL | ST0_ERL | \set | \clr
xor t0, ST0_EXL | ST0_ERL | \clr
mtc0 t0, CP0_STATUS
mfc0 t0, CP0_STATUS
or t0, ST0_CU0|\set|0x1f|\clr
xor t0, 0x1f|\clr
mtc0 t0, CP0_STATUS
.set noreorder
sll zero,3 # ehb
.set pop
.macro setup_c0_status_pri
#ifdef CONFIG_64BIT
setup_c0_status ST0_KX 0
setup_c0_status 0 0
.macro setup_c0_status_sec
#ifdef CONFIG_64BIT
setup_c0_status ST0_KX ST0_BEV
setup_c0_status 0 ST0_BEV
* Reserved space for exception handlers.
* Necessary for machines which link their kernels at KSEG0.
.fill 0x400
* Give us a fighting chance of running if execution beings at the
* kernel load address. This is needed because this platform does
* not have a ELF loader yet.
j kernel_entry
NESTED(kernel_entry, 16, sp) # kernel entry point
kernel_entry_setup # cpu specific setup
/* We might not get launched at the address the kernel is linked to,
so we jump there. */
PTR_LA t0, 0f
jr t0
* In SMTC kernel, "CLI" is thread-specific, in TCStatus.
* We still need to enable interrupts globally in Status,
* and clear EXL/ERL.
* TCContext is used to track interrupt levels under
* service in SMTC kernel. Clear for boot TC before
* allowing any interrupts.
mtc0 zero, CP0_TCCONTEXT
mfc0 t0, CP0_STATUS
ori t0, t0, 0xff1f
xori t0, t0, 0x001e
mtc0 t0, CP0_STATUS
#endif /* CONFIG_MIPS_MT_SMTC */
PTR_LA t0, __bss_start # clear .bss
LONG_S zero, (t0)
PTR_LA t1, __bss_stop - LONGSIZE
LONG_S zero, (t0)
bne t0, t1, 1b
LONG_S a0, fw_arg0 # firmware arguments
LONG_S a1, fw_arg1
LONG_S a2, fw_arg2
LONG_S a3, fw_arg3
MTC0 zero, CP0_CONTEXT # clear context register
PTR_LA $28, init_thread_union
/* Set the SP after an empty pt_regs. */
PTR_ADDU sp, $28
set_saved_sp sp, t0, t1
PTR_SUBU sp, 4 * SZREG # init stack pointer
j start_kernel
* SMP slave cpus entry point. Board specific code for bootstrap calls this
* function after setting up the stack and gp registers.
NESTED(smp_bootstrap, 16, sp)
* Read-modify-writes of Status must be atomic, and this
* is one case where CLI is invoked without EXL being
* necessarily set. The CLI and setup_c0_status will
* in fact be redundant for all but the first TC of
* each VPE being booted.
DMT 10 # dmt t2 /* t0, t1 are used by CLI and setup_c0_status() */
jal mips_ihb
#endif /* CONFIG_MIPS_MT_SMTC */
andi t2, t2, VPECONTROL_TE
beqz t2, 2f
EMT # emt
#endif /* CONFIG_MIPS_MT_SMTC */
j start_secondary
#endif /* CONFIG_SMP */