![Ralf Baechle](/assets/img/avatar_default.png)
set_saved_sp reads Context register. Avoid reading stale value from earlier incomplete write. Issue found and fixed for head.S by Chris Dearman <chris@mips.com>. Signed-off-by: Chris Dearman <chris@mips.com> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
233 lines
5.9 KiB
ArmAsm
233 lines
5.9 KiB
ArmAsm
/*
|
|
* 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
|
|
back_to_back_c0_hazard
|
|
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
|