[PATCH 4/4] ARM: pbl: MMU: Make it callable multiple times

[Sascha Hauer <s.hauer@pengutronix.de>]

mmu_early_enable() is called in barebox_pbl_start() after a call to
setup_c(). setup_c() clears the BSS which means alloc_pte() starts at
index zero again when mmu_early_enable() has been called earlier
already.

Some boards might want to do exactly that: Call mmu_early_enable()
earlier to do for example otherwise expensive hashing of xloaded
binaries.

Make mmu_early_enable() safe to be called multiple times by moving the
PTE index out of the BSS.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 arch/arm/cpu/mmu_64.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/arm/cpu/mmu_64.c b/arch/arm/cpu/mmu_64.c
index 7f38473079..2f451b3c91 100644
--- a/arch/arm/cpu/mmu_64.c
+++ b/arch/arm/cpu/mmu_64.c
@@ -86,7 +86,10 @@ static void set_pte_range(unsigned level, uint64_t *virt, phys_addr_t phys,
 #ifdef __PBL__
 static uint64_t *alloc_pte(void)
 {
-	static unsigned int idx;
+	static int idx = -1;
+
+	if (idx == -1)
+		idx = 0;
 
 	idx++;
 

-- 
2.47.3