Skip to content

Commit

Permalink
[ARM] smp: separate SCU support code from realview
Browse files Browse the repository at this point in the history
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
  • Loading branch information
Russell King authored and Russell King committed May 17, 2009
1 parent 49613d4 commit a8cbcd9
Show file tree
Hide file tree
Showing 5 changed files with 56 additions and 32 deletions.
7 changes: 7 additions & 0 deletions arch/arm/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -861,6 +861,7 @@ config SMP
depends on EXPERIMENTAL && (REALVIEW_EB_ARM11MP || MACH_REALVIEW_PB11MP)
depends on GENERIC_CLOCKEVENTS
select USE_GENERIC_SMP_HELPERS
select HAVE_ARM_SCU if ARCH_REALVIEW
help
This enables support for systems with more than one CPU. If you have
a system with only one CPU, like most personal computers, say N. If
Expand All @@ -878,6 +879,12 @@ config SMP

If you don't know what to do here, say N.

config HAVE_ARM_SCU
bool
depends on SMP
help
This option enables support for the ARM system coherency unit

choice
prompt "Memory split"
default VMSPLIT_3G
Expand Down
10 changes: 2 additions & 8 deletions arch/arm/include/asm/smp_scu.h
Original file line number Diff line number Diff line change
@@ -1,13 +1,7 @@
#ifndef __ASMARM_ARCH_SCU_H
#define __ASMARM_ARCH_SCU_H

/*
* SCU registers
*/
#define SCU_CTRL 0x00
#define SCU_CONFIG 0x04
#define SCU_CPU_STATUS 0x08
#define SCU_INVALIDATE 0x0c
#define SCU_FPGA_REVISION 0x10
unsigned int scu_get_core_count(void __iomem *);
void scu_enable(void __iomem *);

#endif
1 change: 1 addition & 0 deletions arch/arm/kernel/Makefile
Original file line number Diff line number Diff line change
Expand Up @@ -22,6 +22,7 @@ obj-$(CONFIG_ARTHUR) += arthur.o
obj-$(CONFIG_ISA_DMA) += dma-isa.o
obj-$(CONFIG_PCI) += bios32.o isa.o
obj-$(CONFIG_SMP) += smp.o
obj-$(CONFIG_HAVE_ARM_SCU) += smp_scu.o
obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o
obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o
obj-$(CONFIG_KPROBES) += kprobes.o kprobes-decode.o
Expand Down
41 changes: 41 additions & 0 deletions arch/arm/kernel/smp_scu.c
Original file line number Diff line number Diff line change
@@ -0,0 +1,41 @@
/*
* linux/arch/arm/kernel/smp_scu.c
*
* Copyright (C) 2002 ARM Ltd.
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/init.h>
#include <linux/io.h>

#include <asm/smp_scu.h>

#define SCU_CTRL 0x00
#define SCU_CONFIG 0x04
#define SCU_CPU_STATUS 0x08
#define SCU_INVALIDATE 0x0c
#define SCU_FPGA_REVISION 0x10

/*
* Get the number of CPU cores from the SCU configuration
*/
unsigned int __init scu_get_core_count(void __iomem *scu_base)
{
unsigned int ncores = __raw_readl(scu_base + SCU_CONFIG);
return (ncores & 0x03) + 1;
}

/*
* Enable the SCU
*/
void __init scu_enable(void __iomem *scu_base)
{
u32 scu_ctrl;

scu_ctrl = __raw_readl(scu_base + SCU_CTRL);
scu_ctrl |= 1;
__raw_writel(scu_ctrl, scu_base + SCU_CTRL);
}
29 changes: 5 additions & 24 deletions arch/arm/mach-realview/platsmp.c
Original file line number Diff line number Diff line change
Expand Up @@ -45,31 +45,12 @@ static void __iomem *scu_base_addr(void)
return (void __iomem *)0;
}

static unsigned int __init get_core_count(void)
static inline unsigned int get_core_count(void)
{
unsigned int ncores;
void __iomem *scu_base = scu_base_addr();

if (scu_base) {
ncores = __raw_readl(scu_base + SCU_CONFIG);
ncores = (ncores & 0x03) + 1;
} else
ncores = 1;

return ncores;
}

/*
* Setup the SCU
*/
static void scu_enable(void)
{
u32 scu_ctrl;
void __iomem *scu_base = scu_base_addr();

scu_ctrl = __raw_readl(scu_base + SCU_CTRL);
scu_ctrl |= 1;
__raw_writel(scu_ctrl, scu_base + SCU_CTRL);
if (scu_base)
return scu_get_core_count(scu_base);
return 1;
}

static DEFINE_SPINLOCK(boot_lock);
Expand Down Expand Up @@ -239,7 +220,7 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
*/
percpu_timer_setup();

scu_enable();
scu_enable(scu_base_addr());
poke_milo();
}
}

0 comments on commit a8cbcd9

Please sign in to comment.