[PATCH 2/3] ARM: v7r: factor out armv7r_cache_enable

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

We enable caches early on ARMv7-R to speed up decompression.
On ARMv7-A, we need to enable the MMU as well, but for ARMv7-R enabling
the MPU is not necessary and so the code is a one-liner.

That one line will become two in a subsequent commit, so prepare for
that by moving it into an appropriately named helper function.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 arch/arm/cpu/armv7r-mpu.c         | 5 +++++
 arch/arm/cpu/uncompress.c         | 3 ++-
 arch/arm/include/asm/armv7r-mpu.h | 2 ++
 3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/arch/arm/cpu/armv7r-mpu.c b/arch/arm/cpu/armv7r-mpu.c
index d96411a61632..d494aec583ef 100644
--- a/arch/arm/cpu/armv7r-mpu.c
+++ b/arch/arm/cpu/armv7r-mpu.c
@@ -32,6 +32,11 @@
  * [1] http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0460d/I1002400.html
  */
 
+void armv7r_cache_enable(void)
+{
+	set_cr(get_cr() | CR_C);
+}
+
 void armv7r_mpu_disable(void)
 {
 	u32 reg;
diff --git a/arch/arm/cpu/uncompress.c b/arch/arm/cpu/uncompress.c
index 55bbe0019cc4..8f0d0f55f862 100644
--- a/arch/arm/cpu/uncompress.c
+++ b/arch/arm/cpu/uncompress.c
@@ -18,6 +18,7 @@
 #include <asm/secure.h>
 #include <asm/cache.h>
 #include <asm/mmu.h>
+#include <asm/armv7r-mpu.h>
 #include <asm/unaligned.h>
 #include <compressed-dtb.h>
 #include <elf.h>
@@ -87,7 +88,7 @@ void __noreturn barebox_pbl_start(unsigned long membase, unsigned long memsize,
 	if (IS_ENABLED(CONFIG_MMU))
 		mmu_early_enable(membase, memsize);
 	else if (IS_ENABLED(CONFIG_ARMV7R_MPU))
-		set_cr(get_cr() | CR_C);
+		armv7r_cache_enable();
 
 	pr_debug("uncompressing barebox ELF at 0x%p (size 0x%08x) to 0x%08lx (uncompressed size: 0x%08x)\n",
 			pg_start, pg_len, barebox_base, uncompressed_len);
diff --git a/arch/arm/include/asm/armv7r-mpu.h b/arch/arm/include/asm/armv7r-mpu.h
index 8d737d6d1407..1d890ab90a67 100644
--- a/arch/arm/include/asm/armv7r-mpu.h
+++ b/arch/arm/include/asm/armv7r-mpu.h
@@ -91,6 +91,8 @@ struct mpu_region_config {
 	enum size reg_size;
 };
 
+void armv7r_cache_enable(void);
+
 void armv7r_mpu_disable(void);
 void armv7r_mpu_enable(void);
 int armv7r_mpu_enabled(void);
-- 
2.47.3