[PATCH 4/4] ARM: tegra: Set SCU base address dynamically from DT

From: Hiroshi Doyu
Date: Mon Dec 17 2012 - 01:18:47 EST


Set Snoop Control Unit(SCU) register base address dynamically from DT.

Signed-off-by: Hiroshi Doyu <hdoyu@xxxxxxxxxx>
---
arch/arm/mach-tegra/platsmp.c | 23 ++++++++++++++++++++---
1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-tegra/platsmp.c b/arch/arm/mach-tegra/platsmp.c
index 1b926df..45c0b79 100644
--- a/arch/arm/mach-tegra/platsmp.c
+++ b/arch/arm/mach-tegra/platsmp.c
@@ -18,6 +18,8 @@
#include <linux/jiffies.h>
#include <linux/smp.h>
#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>

#include <asm/cacheflush.h>
#include <asm/hardware/gic.h>
@@ -36,7 +38,7 @@

extern void tegra_secondary_startup(void);

-static void __iomem *scu_base = IO_ADDRESS(TEGRA_ARM_PERIF_BASE);
+static void __iomem *scu_base;

#define EVP_CPU_RESET_VECTOR \
(IO_ADDRESS(TEGRA_EXCEPTION_VECTORS_BASE) + 0x100)
@@ -143,14 +145,28 @@ done:
return status;
}

+static const struct of_device_id cortex_a9_scu_match[] __initconst = {
+ { .compatible = "arm,cortex-a9-scu", },
+ {}
+};
+
/*
* Initialise the CPU possible map early - this describes the CPUs
* which may be present or become present in the system.
*/
static void __init tegra_smp_init_cpus(void)
{
- unsigned int i, ncores = scu_get_core_count(scu_base);
+ struct device_node *np;
+ unsigned int i, ncores = 1;
+
+ np = of_find_matching_node(NULL, cortex_a9_scu_match);
+ if (!np)
+ return;
+ scu_base = of_iomap(np, 0);
+ if (!scu_base)
+ return;

+ ncores = scu_get_core_count(scu_base);
if (ncores > nr_cpu_ids) {
pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
ncores, nr_cpu_ids);
@@ -166,7 +182,8 @@ static void __init tegra_smp_init_cpus(void)
static void __init tegra_smp_prepare_cpus(unsigned int max_cpus)
{
tegra_cpu_reset_handler_init();
- scu_enable(scu_base);
+ if (scu_base)
+ scu_enable(scu_base);
}

struct smp_operations tegra_smp_ops __initdata = {
--
1.7.9.5

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