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From 85392359bd3a2002b72d65d1637598c2f1e398b3 Mon Sep 17 00:00:00 2001
From: Mans Rullgard <mans@mansr.com>
Date: Tue, 10 Nov 2009 00:41:54 +0000
Subject: [PATCH 39/42] ARM: Add option to allow userspace PLE access
This adds a Kconfig option to allow userspace to access the L2 preload
engine (PLE) found in Cortex-A8.
Signed-off-by: Mans Rullgard <mans@mansr.com>
---
arch/arm/kernel/head.S | 4 ++++
arch/arm/mm/Kconfig | 8 ++++++++
2 files changed, 12 insertions(+), 0 deletions(-)
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index eb62bf9..659ec9e 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -172,6 +172,10 @@ __enable_mmu:
#ifdef CONFIG_CPU_ICACHE_DISABLE
bic r0, r0, #CR_I
#endif
+#ifdef CONFIG_USER_L2_PLE
+ mov r5, #3
+ mcr p15, 0, r5, c11, c1, 0
+#endif
mov r5, #(domain_val(DOMAIN_USER, DOMAIN_MANAGER) | \
domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \
domain_val(DOMAIN_TABLE, DOMAIN_MANAGER) | \
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
index dd4698c..564ff7d 100644
--- a/arch/arm/mm/Kconfig
+++ b/arch/arm/mm/Kconfig
@@ -785,3 +785,11 @@ config ARM_L1_CACHE_SHIFT
int
default 6 if ARCH_OMAP3 || ARCH_S5PC1XX
default 5
+
+config USER_L2_PLE
+ bool "Enable userspace access to the L2 PLE"
+ depends on CPU_V7
+ default n
+ help
+ Enable userspace access to the L2 preload engine (PLE) available
+ in Cortex-A series ARM processors.
--
1.6.6.1
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