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-rw-r--r--target/linux/mvebu/patches-3.10/0024-arm-mvebu-remove-dependency-of-SMP-init-on-static-I-.patch99
1 files changed, 99 insertions, 0 deletions
diff --git a/target/linux/mvebu/patches-3.10/0024-arm-mvebu-remove-dependency-of-SMP-init-on-static-I-.patch b/target/linux/mvebu/patches-3.10/0024-arm-mvebu-remove-dependency-of-SMP-init-on-static-I-.patch
new file mode 100644
index 0000000000..38c908fb8c
--- /dev/null
+++ b/target/linux/mvebu/patches-3.10/0024-arm-mvebu-remove-dependency-of-SMP-init-on-static-I-.patch
@@ -0,0 +1,99 @@
+From 9398729313b826469fede3acda5fedd1eb21cb3e Mon Sep 17 00:00:00 2001
+From: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
+Date: Wed, 5 Jun 2013 09:04:54 +0200
+Subject: [PATCH 024/203] arm: mvebu: remove dependency of SMP init on static
+ I/O mapping
+
+The ->smp_init_cpus() function is called very early during boot, at a
+point where dynamic I/O mappings are not yet possible. However, in the
+Armada 370/XP implementation of this function, we have to get the
+number of CPUs. We used to do that by accessing a hardware register,
+which requires relying on a static I/O mapping set up by
+->map_io(). Not only this requires hardcoding a virtual address, but
+it also prevents us from removing the static I/O mapping.
+
+So this commit changes the way used to get the number of CPUs: we now
+use the Device Tree, which is a representation of the hardware, and
+provides us the number of available CPUs. This is also more accurate,
+because it potentially allows to boot the Linux kernel on only a
+number of CPUs given by the Device Tree, instead of unconditionally on
+all CPUs.
+
+As a consequence, the coherency_get_cpu_count() function becomes no
+longer used, so we remove it.
+
+Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
+Acked-by: Arnd Bergmann <arnd@arndb.de>
+Signed-off-by: Jason Cooper <jason@lakedaemon.net>
+---
+ arch/arm/mach-mvebu/coherency.c | 12 ------------
+ arch/arm/mach-mvebu/coherency.h | 4 ----
+ arch/arm/mach-mvebu/common.h | 2 ++
+ arch/arm/mach-mvebu/platsmp.c | 10 +++++++++-
+ 4 files changed, 11 insertions(+), 17 deletions(-)
+
+--- a/arch/arm/mach-mvebu/coherency.c
++++ b/arch/arm/mach-mvebu/coherency.c
+@@ -47,18 +47,6 @@ static struct of_device_id of_coherency_
+ { /* end of list */ },
+ };
+
+-#ifdef CONFIG_SMP
+-int coherency_get_cpu_count(void)
+-{
+- int reg, cnt;
+-
+- reg = readl(coherency_base + COHERENCY_FABRIC_CFG_OFFSET);
+- cnt = (reg & 0xF) + 1;
+-
+- return cnt;
+-}
+-#endif
+-
+ /* Function defined in coherency_ll.S */
+ int ll_set_cpu_coherent(void __iomem *base_addr, unsigned int hw_cpu_id);
+
+--- a/arch/arm/mach-mvebu/coherency.h
++++ b/arch/arm/mach-mvebu/coherency.h
+@@ -14,10 +14,6 @@
+ #ifndef __MACH_370_XP_COHERENCY_H
+ #define __MACH_370_XP_COHERENCY_H
+
+-#ifdef CONFIG_SMP
+-int coherency_get_cpu_count(void);
+-#endif
+-
+ int set_cpu_coherent(int cpu_id, int smp_group_id);
+ int coherency_init(void);
+
+--- a/arch/arm/mach-mvebu/common.h
++++ b/arch/arm/mach-mvebu/common.h
+@@ -15,6 +15,8 @@
+ #ifndef __ARCH_MVEBU_COMMON_H
+ #define __ARCH_MVEBU_COMMON_H
+
++#define ARMADA_XP_MAX_CPUS 4
++
+ void mvebu_restart(char mode, const char *cmd);
+
+ void armada_370_xp_init_irq(void);
+--- a/arch/arm/mach-mvebu/platsmp.c
++++ b/arch/arm/mach-mvebu/platsmp.c
+@@ -88,8 +88,16 @@ static int __cpuinit armada_xp_boot_seco
+
+ static void __init armada_xp_smp_init_cpus(void)
+ {
++ struct device_node *np;
+ unsigned int i, ncores;
+- ncores = coherency_get_cpu_count();
++
++ np = of_find_node_by_name(NULL, "cpus");
++ if (!np)
++ panic("No 'cpus' node found\n");
++
++ ncores = of_get_child_count(np);
++ if (ncores == 0 || ncores > ARMADA_XP_MAX_CPUS)
++ panic("Invalid number of CPUs in DT\n");
+
+ /* Limit possible CPUs to defconfig */
+ if (ncores > nr_cpu_ids) {