linux/arch/mips/kernel/cps-vec.S
Markos Chandras 6521d9a436 MIPS: CPS: Initialize EVA before bringing up VPEs from secondary cores
The CPS code is doing several memory loads when configuring the VPEs
from secondary cores, so the segmentation control registers must be
initialized in time otherwise the kernel will crash with strange
TLB exceptions.

Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: http://patchwork.linux-mips.org/patch/7424/
Signed-off-by: James Hogan <james.hogan@imgtec.com>
2014-08-19 18:24:41 +02:00

492 lines
9.1 KiB
ArmAsm

/*
* Copyright (C) 2013 Imagination Technologies
* Author: Paul Burton <paul.burton@imgtec.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <asm/addrspace.h>
#include <asm/asm.h>
#include <asm/asm-offsets.h>
#include <asm/asmmacro.h>
#include <asm/cacheops.h>
#include <asm/eva.h>
#include <asm/mipsregs.h>
#include <asm/mipsmtregs.h>
#include <asm/pm.h>
#define GCR_CL_COHERENCE_OFS 0x2008
#define GCR_CL_ID_OFS 0x2028
.extern mips_cm_base
.set noreorder
/*
* Set dest to non-zero if the core supports the MT ASE, else zero. If
* MT is not supported then branch to nomt.
*/
.macro has_mt dest, nomt
mfc0 \dest, CP0_CONFIG
bgez \dest, \nomt
mfc0 \dest, CP0_CONFIG, 1
bgez \dest, \nomt
mfc0 \dest, CP0_CONFIG, 2
bgez \dest, \nomt
mfc0 \dest, CP0_CONFIG, 3
andi \dest, \dest, MIPS_CONF3_MT
beqz \dest, \nomt
.endm
.section .text.cps-vec
.balign 0x1000
LEAF(mips_cps_core_entry)
/*
* These first 12 bytes will be patched by cps_smp_setup to load the
* base address of the CM GCRs into register v1 and the CCA to use into
* register s0.
*/
.quad 0
.word 0
/* Check whether we're here due to an NMI */
mfc0 k0, CP0_STATUS
and k0, k0, ST0_NMI
beqz k0, not_nmi
nop
/* This is an NMI */
la k0, nmi_handler
jr k0
nop
not_nmi:
/* Setup Cause */
li t0, CAUSEF_IV
mtc0 t0, CP0_CAUSE
/* Setup Status */
li t0, ST0_CU1 | ST0_CU0
mtc0 t0, CP0_STATUS
/*
* Clear the bits used to index the caches. Note that the architecture
* dictates that writing to any of TagLo or TagHi selects 0 or 2 should
* be valid for all MIPS32 CPUs, even those for which said writes are
* unnecessary.
*/
mtc0 zero, CP0_TAGLO, 0
mtc0 zero, CP0_TAGHI, 0
mtc0 zero, CP0_TAGLO, 2
mtc0 zero, CP0_TAGHI, 2
ehb
/* Primary cache configuration is indicated by Config1 */
mfc0 v0, CP0_CONFIG, 1
/* Detect I-cache line size */
_EXT t0, v0, MIPS_CONF1_IL_SHF, MIPS_CONF1_IL_SZ
beqz t0, icache_done
li t1, 2
sllv t0, t1, t0
/* Detect I-cache size */
_EXT t1, v0, MIPS_CONF1_IS_SHF, MIPS_CONF1_IS_SZ
xori t2, t1, 0x7
beqz t2, 1f
li t3, 32
addi t1, t1, 1
sllv t1, t3, t1
1: /* At this point t1 == I-cache sets per way */
_EXT t2, v0, MIPS_CONF1_IA_SHF, MIPS_CONF1_IA_SZ
addi t2, t2, 1
mul t1, t1, t0
mul t1, t1, t2
li a0, KSEG0
add a1, a0, t1
1: cache Index_Store_Tag_I, 0(a0)
add a0, a0, t0
bne a0, a1, 1b
nop
icache_done:
/* Detect D-cache line size */
_EXT t0, v0, MIPS_CONF1_DL_SHF, MIPS_CONF1_DL_SZ
beqz t0, dcache_done
li t1, 2
sllv t0, t1, t0
/* Detect D-cache size */
_EXT t1, v0, MIPS_CONF1_DS_SHF, MIPS_CONF1_DS_SZ
xori t2, t1, 0x7
beqz t2, 1f
li t3, 32
addi t1, t1, 1
sllv t1, t3, t1
1: /* At this point t1 == D-cache sets per way */
_EXT t2, v0, MIPS_CONF1_DA_SHF, MIPS_CONF1_DA_SZ
addi t2, t2, 1
mul t1, t1, t0
mul t1, t1, t2
li a0, KSEG0
addu a1, a0, t1
subu a1, a1, t0
1: cache Index_Store_Tag_D, 0(a0)
bne a0, a1, 1b
add a0, a0, t0
dcache_done:
/* Set Kseg0 CCA to that in s0 */
mfc0 t0, CP0_CONFIG
ori t0, 0x7
xori t0, 0x7
or t0, t0, s0
mtc0 t0, CP0_CONFIG
ehb
/* Enter the coherent domain */
li t0, 0xff
sw t0, GCR_CL_COHERENCE_OFS(v1)
ehb
/* Jump to kseg0 */
la t0, 1f
jr t0
nop
/*
* We're up, cached & coherent. Perform any further required core-level
* initialisation.
*/
1: jal mips_cps_core_init
nop
/* Do any EVA initialization if necessary */
eva_init
/*
* Boot any other VPEs within this core that should be online, and
* deactivate this VPE if it should be offline.
*/
jal mips_cps_boot_vpes
nop
/* Off we go! */
lw t1, VPEBOOTCFG_PC(v0)
lw gp, VPEBOOTCFG_GP(v0)
lw sp, VPEBOOTCFG_SP(v0)
jr t1
nop
END(mips_cps_core_entry)
.org 0x200
LEAF(excep_tlbfill)
b .
nop
END(excep_tlbfill)
.org 0x280
LEAF(excep_xtlbfill)
b .
nop
END(excep_xtlbfill)
.org 0x300
LEAF(excep_cache)
b .
nop
END(excep_cache)
.org 0x380
LEAF(excep_genex)
b .
nop
END(excep_genex)
.org 0x400
LEAF(excep_intex)
b .
nop
END(excep_intex)
.org 0x480
LEAF(excep_ejtag)
la k0, ejtag_debug_handler
jr k0
nop
END(excep_ejtag)
LEAF(mips_cps_core_init)
#ifdef CONFIG_MIPS_MT
/* Check that the core implements the MT ASE */
has_mt t0, 3f
nop
.set push
.set mt
/* Only allow 1 TC per VPE to execute... */
dmt
/* ...and for the moment only 1 VPE */
dvpe
la t1, 1f
jr.hb t1
nop
/* Enter VPE configuration state */
1: mfc0 t0, CP0_MVPCONTROL
ori t0, t0, MVPCONTROL_VPC
mtc0 t0, CP0_MVPCONTROL
/* Retrieve the number of VPEs within the core */
mfc0 t0, CP0_MVPCONF0
srl t0, t0, MVPCONF0_PVPE_SHIFT
andi t0, t0, (MVPCONF0_PVPE >> MVPCONF0_PVPE_SHIFT)
addi t7, t0, 1
/* If there's only 1, we're done */
beqz t0, 2f
nop
/* Loop through each VPE within this core */
li t5, 1
1: /* Operate on the appropriate TC */
mtc0 t5, CP0_VPECONTROL
ehb
/* Bind TC to VPE (1:1 TC:VPE mapping) */
mttc0 t5, CP0_TCBIND
/* Set exclusive TC, non-active, master */
li t0, VPECONF0_MVP
sll t1, t5, VPECONF0_XTC_SHIFT
or t0, t0, t1
mttc0 t0, CP0_VPECONF0
/* Set TC non-active, non-allocatable */
mttc0 zero, CP0_TCSTATUS
/* Set TC halted */
li t0, TCHALT_H
mttc0 t0, CP0_TCHALT
/* Next VPE */
addi t5, t5, 1
slt t0, t5, t7
bnez t0, 1b
nop
/* Leave VPE configuration state */
2: mfc0 t0, CP0_MVPCONTROL
xori t0, t0, MVPCONTROL_VPC
mtc0 t0, CP0_MVPCONTROL
3: .set pop
#endif
jr ra
nop
END(mips_cps_core_init)
LEAF(mips_cps_boot_vpes)
/* Retrieve CM base address */
la t0, mips_cm_base
lw t0, 0(t0)
/* Calculate a pointer to this cores struct core_boot_config */
lw t0, GCR_CL_ID_OFS(t0)
li t1, COREBOOTCFG_SIZE
mul t0, t0, t1
la t1, mips_cps_core_bootcfg
lw t1, 0(t1)
addu t0, t0, t1
/* Calculate this VPEs ID. If the core doesn't support MT use 0 */
has_mt t6, 1f
li t9, 0
/* Find the number of VPEs present in the core */
mfc0 t1, CP0_MVPCONF0
srl t1, t1, MVPCONF0_PVPE_SHIFT
andi t1, t1, MVPCONF0_PVPE >> MVPCONF0_PVPE_SHIFT
addi t1, t1, 1
/* Calculate a mask for the VPE ID from EBase.CPUNum */
clz t1, t1
li t2, 31
subu t1, t2, t1
li t2, 1
sll t1, t2, t1
addiu t1, t1, -1
/* Retrieve the VPE ID from EBase.CPUNum */
mfc0 t9, $15, 1
and t9, t9, t1
1: /* Calculate a pointer to this VPEs struct vpe_boot_config */
li t1, VPEBOOTCFG_SIZE
mul v0, t9, t1
lw t7, COREBOOTCFG_VPECONFIG(t0)
addu v0, v0, t7
#ifdef CONFIG_MIPS_MT
/* If the core doesn't support MT then return */
bnez t6, 1f
nop
jr ra
nop
.set push
.set mt
1: /* Enter VPE configuration state */
dvpe
la t1, 1f
jr.hb t1
nop
1: mfc0 t1, CP0_MVPCONTROL
ori t1, t1, MVPCONTROL_VPC
mtc0 t1, CP0_MVPCONTROL
ehb
/* Loop through each VPE */
lw t6, COREBOOTCFG_VPEMASK(t0)
move t8, t6
li t5, 0
/* Check whether the VPE should be running. If not, skip it */
1: andi t0, t6, 1
beqz t0, 2f
nop
/* Operate on the appropriate TC */
mfc0 t0, CP0_VPECONTROL
ori t0, t0, VPECONTROL_TARGTC
xori t0, t0, VPECONTROL_TARGTC
or t0, t0, t5
mtc0 t0, CP0_VPECONTROL
ehb
/* Skip the VPE if its TC is not halted */
mftc0 t0, CP0_TCHALT
beqz t0, 2f
nop
/* Calculate a pointer to the VPEs struct vpe_boot_config */
li t0, VPEBOOTCFG_SIZE
mul t0, t0, t5
addu t0, t0, t7
/* Set the TC restart PC */
lw t1, VPEBOOTCFG_PC(t0)
mttc0 t1, CP0_TCRESTART
/* Set the TC stack pointer */
lw t1, VPEBOOTCFG_SP(t0)
mttgpr t1, sp
/* Set the TC global pointer */
lw t1, VPEBOOTCFG_GP(t0)
mttgpr t1, gp
/* Copy config from this VPE */
mfc0 t0, CP0_CONFIG
mttc0 t0, CP0_CONFIG
/* Ensure no software interrupts are pending */
mttc0 zero, CP0_CAUSE
mttc0 zero, CP0_STATUS
/* Set TC active, not interrupt exempt */
mftc0 t0, CP0_TCSTATUS
li t1, ~TCSTATUS_IXMT
and t0, t0, t1
ori t0, t0, TCSTATUS_A
mttc0 t0, CP0_TCSTATUS
/* Clear the TC halt bit */
mttc0 zero, CP0_TCHALT
/* Set VPE active */
mftc0 t0, CP0_VPECONF0
ori t0, t0, VPECONF0_VPA
mttc0 t0, CP0_VPECONF0
/* Next VPE */
2: srl t6, t6, 1
addi t5, t5, 1
bnez t6, 1b
nop
/* Leave VPE configuration state */
mfc0 t1, CP0_MVPCONTROL
xori t1, t1, MVPCONTROL_VPC
mtc0 t1, CP0_MVPCONTROL
ehb
evpe
/* Check whether this VPE is meant to be running */
li t0, 1
sll t0, t0, t9
and t0, t0, t8
bnez t0, 2f
nop
/* This VPE should be offline, halt the TC */
li t0, TCHALT_H
mtc0 t0, CP0_TCHALT
la t0, 1f
1: jr.hb t0
nop
2: .set pop
#endif /* CONFIG_MIPS_MT */
/* Return */
jr ra
nop
END(mips_cps_boot_vpes)
#if defined(CONFIG_MIPS_CPS_PM) && defined(CONFIG_CPU_PM)
/* Calculate a pointer to this CPUs struct mips_static_suspend_state */
.macro psstate dest
.set push
.set noat
lw $1, TI_CPU(gp)
sll $1, $1, LONGLOG
la \dest, __per_cpu_offset
addu $1, $1, \dest
lw $1, 0($1)
la \dest, cps_cpu_state
addu \dest, \dest, $1
.set pop
.endm
LEAF(mips_cps_pm_save)
/* Save CPU state */
SUSPEND_SAVE_REGS
psstate t1
SUSPEND_SAVE_STATIC
jr v0
nop
END(mips_cps_pm_save)
LEAF(mips_cps_pm_restore)
/* Restore CPU state */
psstate t1
RESUME_RESTORE_STATIC
RESUME_RESTORE_REGS_RETURN
END(mips_cps_pm_restore)
#endif /* CONFIG_MIPS_CPS_PM && CONFIG_CPU_PM */