linux/arch/mips/kernel/bmips_vec.S
Florian Fainelli ff5fadaff3 MIPS: BMIPS: fix slave CPU booting when physical CPU is not 0
The current BMIPS SMP code assumes that the slave CPU is physical and
logical CPU 1, but on some systems such as BCM3368, the slave CPU is
physical CPU0. Fix the code to read the physical CPU (thread ID) we are
running this code on, and adjust the relocation vector address based on
it. This allows bringing up the second CPU on BCM3368 for instance.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: cernekee@gmail.com
Cc: jogo@openwrt.org
Cc: blogic@openwrt.org
Patchwork: https://patchwork.linux-mips.org/patch/5621/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-07-30 18:54:29 +02:00

256 lines
5.4 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) 2011 by Kevin Cernekee (cernekee@gmail.com)
*
* Reset/NMI/re-entry vectors for BMIPS processors
*/
#include <linux/init.h>
#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/cacheops.h>
#include <asm/regdef.h>
#include <asm/mipsregs.h>
#include <asm/stackframe.h>
#include <asm/addrspace.h>
#include <asm/hazards.h>
#include <asm/bmips.h>
.macro BARRIER
.set mips32
_ssnop
_ssnop
_ssnop
.set mips0
.endm
/***********************************************************************
* Alternate CPU1 startup vector for BMIPS4350
*
* On some systems the bootloader has already started CPU1 and configured
* it to resume execution at 0x8000_0200 (!BEV IV vector) when it is
* triggered by the SW1 interrupt. If that is the case we try to move
* it to a more convenient place: BMIPS_WARM_RESTART_VEC @ 0x8000_0380.
***********************************************************************/
LEAF(bmips_smp_movevec)
la k0, 1f
li k1, CKSEG1
or k0, k1
jr k0
1:
/* clear IV, pending IPIs */
mtc0 zero, CP0_CAUSE
/* re-enable IRQs to wait for SW1 */
li k0, ST0_IE | ST0_BEV | STATUSF_IP1
mtc0 k0, CP0_STATUS
/* set up CPU1 CBR; move BASE to 0xa000_0000 */
li k0, 0xff400000
mtc0 k0, $22, 6
/* set up relocation vector address based on thread ID */
mfc0 k1, $22, 3
srl k1, 16
andi k1, 0x8000
or k1, CKSEG1 | BMIPS_RELO_VECTOR_CONTROL_0
or k0, k1
li k1, 0xa0080000
sw k1, 0(k0)
/* wait here for SW1 interrupt from bmips_boot_secondary() */
wait
la k0, bmips_reset_nmi_vec
li k1, CKSEG1
or k0, k1
jr k0
END(bmips_smp_movevec)
/***********************************************************************
* Reset/NMI vector
* For BMIPS processors that can relocate their exception vectors, this
* entire function gets copied to 0x8000_0000.
***********************************************************************/
NESTED(bmips_reset_nmi_vec, PT_SIZE, sp)
.set push
.set noat
.align 4
#ifdef CONFIG_SMP
/* if the NMI bit is clear, assume this is a CPU1 reset instead */
li k1, (1 << 19)
mfc0 k0, CP0_STATUS
and k0, k1
beqz k0, bmips_smp_entry
#if defined(CONFIG_CPU_BMIPS5000)
/* if we're not on core 0, this must be the SMP boot signal */
li k1, (3 << 25)
mfc0 k0, $22
and k0, k1
bnez k0, bmips_smp_entry
#endif
#endif /* CONFIG_SMP */
/* nope, it's just a regular NMI */
SAVE_ALL
move a0, sp
/* clear EXL, ERL, BEV so that TLB refills still work */
mfc0 k0, CP0_STATUS
li k1, ST0_ERL | ST0_EXL | ST0_BEV | ST0_IE
or k0, k1
xor k0, k1
mtc0 k0, CP0_STATUS
BARRIER
/* jump to the NMI handler function */
la k0, nmi_handler
jr k0
RESTORE_ALL
.set mips3
eret
/***********************************************************************
* CPU1 reset vector (used for the initial boot only)
* This is still part of bmips_reset_nmi_vec().
***********************************************************************/
#ifdef CONFIG_SMP
bmips_smp_entry:
/* set up CP0 STATUS; enable FPU */
li k0, 0x30000000
mtc0 k0, CP0_STATUS
BARRIER
/* set local CP0 CONFIG to make kseg0 cacheable, write-back */
mfc0 k0, CP0_CONFIG
ori k0, 0x07
xori k0, 0x04
mtc0 k0, CP0_CONFIG
#if defined(CONFIG_CPU_BMIPS4350) || defined(CONFIG_CPU_BMIPS4380)
/* initialize CPU1's local I-cache */
li k0, 0x80000000
li k1, 0x80010000
mtc0 zero, $28
mtc0 zero, $28, 1
BARRIER
1: cache Index_Store_Tag_I, 0(k0)
addiu k0, 16
bne k0, k1, 1b
#elif defined(CONFIG_CPU_BMIPS5000)
/* set exception vector base */
la k0, ebase
lw k0, 0(k0)
mtc0 k0, $15, 1
BARRIER
#endif
/* jump back to kseg0 in case we need to remap the kseg1 area */
la k0, 1f
jr k0
1:
la k0, bmips_enable_xks01
jalr k0
/* use temporary stack to set up upper memory TLB */
li sp, BMIPS_WARM_RESTART_VEC
la k0, plat_wired_tlb_setup
jalr k0
/* switch to permanent stack and continue booting */
.global bmips_secondary_reentry
bmips_secondary_reentry:
la k0, bmips_smp_boot_sp
lw sp, 0(k0)
la k0, bmips_smp_boot_gp
lw gp, 0(k0)
la k0, start_secondary
jr k0
#endif /* CONFIG_SMP */
.align 4
.global bmips_reset_nmi_vec_end
bmips_reset_nmi_vec_end:
END(bmips_reset_nmi_vec)
.set pop
.previous
/***********************************************************************
* CPU1 warm restart vector (used for second and subsequent boots).
* Also used for S2 standby recovery (PM).
* This entire function gets copied to (BMIPS_WARM_RESTART_VEC)
***********************************************************************/
LEAF(bmips_smp_int_vec)
.align 4
mfc0 k0, CP0_STATUS
ori k0, 0x01
xori k0, 0x01
mtc0 k0, CP0_STATUS
eret
.align 4
.global bmips_smp_int_vec_end
bmips_smp_int_vec_end:
END(bmips_smp_int_vec)
/***********************************************************************
* XKS01 support
* Certain CPUs support extending kseg0 to 1024MB.
***********************************************************************/
LEAF(bmips_enable_xks01)
#if defined(CONFIG_XKS01)
#if defined(CONFIG_CPU_BMIPS4380)
mfc0 t0, $22, 3
li t1, 0x1ff0
li t2, (1 << 12) | (1 << 9)
or t0, t1
xor t0, t1
or t0, t2
mtc0 t0, $22, 3
BARRIER
#elif defined(CONFIG_CPU_BMIPS5000)
mfc0 t0, $22, 5
li t1, 0x01ff
li t2, (1 << 8) | (1 << 5)
or t0, t1
xor t0, t1
or t0, t2
mtc0 t0, $22, 5
BARRIER
#else
#error Missing XKS01 setup
#endif
#endif /* defined(CONFIG_XKS01) */
jr ra
END(bmips_enable_xks01)
.previous