linux/arch/mips/include/asm/mach-cavium-octeon/kernel-entry-init.h
David Daney 0ec315121c MIPS: OCTEON: Get rid of CONFIG_CAVIUM_OCTEON_HW_FIX_UNALIGNED
When you turn it off, the kernel is unusable, so get rid of the option
and always allow unaligned access.

The Octeon specific memcpy intentionally does unaligned accesses and it
must not fault.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5303/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-06-10 18:01:25 +02:00

132 lines
3.4 KiB
C

/*
* 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) 2005-2008 Cavium Networks, Inc
*/
#ifndef __ASM_MACH_CAVIUM_OCTEON_KERNEL_ENTRY_H
#define __ASM_MACH_CAVIUM_OCTEON_KERNEL_ENTRY_H
#define CP0_CYCLE_COUNTER $9, 6
#define CP0_CVMCTL_REG $9, 7
#define CP0_CVMMEMCTL_REG $11,7
#define CP0_PRID_REG $15, 0
#define CP0_PRID_OCTEON_PASS1 0x000d0000
#define CP0_PRID_OCTEON_CN30XX 0x000d0200
.macro kernel_entry_setup
# Registers set by bootloader:
# (only 32 bits set by bootloader, all addresses are physical
# addresses, and need to have the appropriate memory region set
# by the kernel
# a0 = argc
# a1 = argv (kseg0 compat addr)
# a2 = 1 if init core, zero otherwise
# a3 = address of boot descriptor block
.set push
.set arch=octeon
# Read the cavium mem control register
dmfc0 v0, CP0_CVMMEMCTL_REG
# Clear the lower 6 bits, the CVMSEG size
dins v0, $0, 0, 6
ori v0, CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE
dmtc0 v0, CP0_CVMMEMCTL_REG # Write the cavium mem control register
dmfc0 v0, CP0_CVMCTL_REG # Read the cavium control register
# Disable unaligned load/store support but leave HW fixup enabled
# Needed for octeon specific memcpy
or v0, v0, 0x5001
xor v0, v0, 0x1001
# Read the processor ID register
mfc0 v1, CP0_PRID_REG
# Disable instruction prefetching (Octeon Pass1 errata)
or v0, v0, 0x2000
# Skip reenable of prefetching for Octeon Pass1
beq v1, CP0_PRID_OCTEON_PASS1, skip
nop
# Reenable instruction prefetching, not on Pass1
xor v0, v0, 0x2000
# Strip off pass number off of processor id
srl v1, 8
sll v1, 8
# CN30XX needs some extra stuff turned off for better performance
bne v1, CP0_PRID_OCTEON_CN30XX, skip
nop
# CN30XX Use random Icache replacement
or v0, v0, 0x400
# CN30XX Disable instruction prefetching
or v0, v0, 0x2000
skip:
# First clear off CvmCtl[IPPCI] bit and move the performance
# counters interrupt to IRQ 6
li v1, ~(7 << 7)
and v0, v0, v1
ori v0, v0, (6 << 7)
# Write the cavium control register
dmtc0 v0, CP0_CVMCTL_REG
sync
# Flush dcache after config change
cache 9, 0($0)
# Get my core id
rdhwr v0, $0
# Jump the master to kernel_entry
bne a2, zero, octeon_main_processor
nop
#ifdef CONFIG_SMP
#
# All cores other than the master need to wait here for SMP bootstrap
# to begin
#
# This is the variable where the next core to boot os stored
PTR_LA t0, octeon_processor_boot
octeon_spin_wait_boot:
# Get the core id of the next to be booted
LONG_L t1, (t0)
# Keep looping if it isn't me
bne t1, v0, octeon_spin_wait_boot
nop
# Get my GP from the global variable
PTR_LA t0, octeon_processor_gp
LONG_L gp, (t0)
# Get my SP from the global variable
PTR_LA t0, octeon_processor_sp
LONG_L sp, (t0)
# Set the SP global variable to zero so the master knows we've started
LONG_S zero, (t0)
#ifdef __OCTEON__
syncw
syncw
#else
sync
#endif
# Jump to the normal Linux SMP entry point
j smp_bootstrap
nop
#else /* CONFIG_SMP */
#
# Someone tried to boot SMP with a non SMP kernel. All extra cores
# will halt here.
#
octeon_wait_forever:
wait
b octeon_wait_forever
nop
#endif /* CONFIG_SMP */
octeon_main_processor:
.set pop
.endm
/*
* Do SMP slave processor setup necessary before we can savely execute C code.
*/
.macro smp_slave_setup
.endm
#endif /* __ASM_MACH_CAVIUM_OCTEON_KERNEL_ENTRY_H */