/*
* 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, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
* 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/page.h>
#include <asm/pgtable-bits.h>
#include <asm/mipsregs.h>
#include <asm/stackframe.h>
#include <kernel-entry-init.h>
/*
* inputs are the text nasid in t1, data nasid in t2.
*/
.macro MAPPED_KERNEL_SETUP_TLB
#ifdef CONFIG_MAPPED_KERNEL
/*
* This needs to read the nasid - assume 0 for now.
* Drop in 0xffffffffc0000000 in tlbhi, 0+VG in tlblo_0,
* 0+DVG in tlblo_1.
*/
dli t0, 0xffffffffc0000000
dmtc0 t0, CP0_ENTRYHI
li t0, 0x1c000 # Offset of text into node memory
dsll t1, NASID_SHFT # Shift text nasid into place
dsll t2, NASID_SHFT # Same for data nasid
or t1, t1, t0 # Physical load address of kernel text
or t2, t2, t0 # Physical load address of kernel data
dsrl t1, 12 # 4K pfn
dsrl t2, 12 # 4K pfn
dsll t1, 6 # Get pfn into place
dsll t2, 6 # Get pfn into place
li t0, ((_PAGE_GLOBAL|_PAGE_VALID| _CACHE_CACHABLE_COW) >> 6)
or t0, t0, t1
mtc0 t0, CP0_ENTRYLO0 # physaddr, VG, cach exlwr
li t0, ((_PAGE_GLOBAL|_PAGE_VALID| _PAGE_DIRTY|_CACHE_CACHABLE_COW) >> 6)
or t0, t0, t2
mtc0 t0, CP0_ENTRYLO1 # physaddr, DVG, cach exlwr
li t0, 0x1ffe000 # MAPPED_KERN_TLBMASK, TLBPGMASK_16M
mtc0 t0, CP0_PAGEMASK
li t0, 0 # KMAP_INX
mtc0 t0, CP0_INDEX
li t0, 1
mtc0 t0, CP0_WIRED
tlbwi
#else
mtc0 zero, CP0_WIRED
#endif
.endm
/*
* 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
#ifdef CONFIG_MIPS_MT_SMTC
/*
* 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
_ehb
/* 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
#else
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
#endif
.set pop
.endm
.macro setup_c0_status_pri
#ifdef CONFIG_64BIT
setup_c0_status ST0_KX 0
#else
setup_c0_status 0 0
#endif
.endm
.macro setup_c0_status_sec
#ifdef CONFIG_64BIT
setup_c0_status ST0_KX ST0_BEV
#else
setup_c0_status 0 ST0_BEV
#endif
.endm
#ifndef CONFIG_NO_EXCEPT_FILL
/*
* Reserved space for exception handlers.
* Necessary for machines which link their kernels at KSEG0.
*/
.fill 0x400
#endif
EXPORT(_stext)
#ifdef CONFIG_BOOT_RAW
/*
* 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.
*/
FEXPORT(__kernel_entry)
j kernel_entry
#endif
__REF
NESTED(kernel_entry, 16, sp) # kernel entry point
kernel_entry_setup # cpu specific setup
setup_c0_status_pri
/* We might not get launched at the address the kernel is linked to,
so we jump there. */
PTR_LA t0, 0f
jr t0
0:
#ifdef CONFIG_MIPS_MT_SMTC
/*
* 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
1:
PTR_ADDIU t0, 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_LI sp, _THREAD_SIZE - 32 - PT_SIZE
PTR_ADDU sp, $28
set_saved_sp sp, t0, t1
PTR_SUBU sp, 4 * SZREG # init stack pointer
j start_kernel
END(kernel_entry)
__CPUINIT
#ifdef CONFIG_SMP
/*
* 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)
#ifdef CONFIG_MIPS_MT_SMTC
/*
* 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 */
setup_c0_status_sec
smp_slave_setup
#ifdef CONFIG_MIPS_MT_SMTC
andi t2, t2, VPECONTROL_TE
beqz t2, 2f
EMT # emt
2:
#endif /* CONFIG_MIPS_MT_SMTC */
j start_secondary
END(smp_bootstrap)
#endif /* CONFIG_SMP */
__FINIT
