mirror of
https://github.com/torvalds/linux.git
synced 2024-12-23 11:21:33 +00:00
33419a69a5
When booting secondary CPUs we have used the main CPU to set up the Snoop Control Unit flags of these CPUs. It is a cleaner approach if every CPU takes care of its own flags. We avoid the need for locking and the program logic is more concise. With this patch the file headsmp-sh73a0.S is added that contains a startup vector for secondary CPUs that sets up its own SCU flags. Further in sh73a0_smp_prepare_cpus() we can rely on the generic ARM helper scu_power_mode(). This is possible as we don't cross borders anymore (every CPU handles its own flags) and need no locking. So we can throw out the needless function modify_scu_cpu_psr(). Signed-off-by: Bastian Hecht <hechtb+renesas@gmail.com> Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
51 lines
1.7 KiB
ArmAsm
51 lines
1.7 KiB
ArmAsm
/*
|
|
* SMP support for SoC sh73a0
|
|
*
|
|
* Copyright (C) 2012 Bastian Hecht
|
|
*
|
|
* 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.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR /PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
|
|
* MA 02111-1307 USA
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
#include <linux/init.h>
|
|
#include <asm/memory.h>
|
|
|
|
__CPUINIT
|
|
/*
|
|
* Reset vector for secondary CPUs.
|
|
*
|
|
* First we turn on L1 cache coherency for our CPU. Then we jump to
|
|
* shmobile_invalidate_start that invalidates the cache and hands over control
|
|
* to the common ARM startup code.
|
|
* This function will be mapped to address 0 by the SBAR register.
|
|
* A normal branch is out of range here so we need a long jump. We jump to
|
|
* the physical address as the MMU is still turned off.
|
|
*/
|
|
.align 12
|
|
ENTRY(sh73a0_secondary_vector)
|
|
mrc p15, 0, r0, c0, c0, 5 @ read MIPDR
|
|
and r0, r0, #3 @ mask out cpu ID
|
|
lsl r0, r0, #3 @ we will shift by cpu_id * 8 bits
|
|
mov r1, #0xf0000000 @ SCU base address
|
|
ldr r2, [r1, #8] @ SCU Power Status Register
|
|
mov r3, #3
|
|
bic r2, r2, r3, lsl r0 @ Clear bits of our CPU (Run Mode)
|
|
str r2, [r1, #8] @ write back
|
|
|
|
ldr pc, 1f
|
|
1: .long shmobile_invalidate_start - PAGE_OFFSET + PLAT_PHYS_OFFSET
|
|
ENDPROC(sh73a0_secondary_vector)
|