[U-Boot] [PATCH] armv8: fsl-layerscape: mmu: Fix enabling MMU

[York Sun]

MMU bit in SCTLR needs to be set explicitly after tables are
created. It isn't an issue for EL3 becuase this bit is already
set by early MMU setup. But for other exception levels this
bit was not set.

Signed-off-by: York Sun <york.sun at nxp.com>
---
Setting CR_M bit wasn't needed for this function when U-Boot runs at EL3.
Recent additional of PPA, and pending change of distro boot requires MMU
to be setup for EL2. This bit needs to be set in _this_ function.

Verified on LS1043ARDB with PPA.
Verified on LS2080ARDB with distro boot (Alex Graf's patch set)

 arch/arm/cpu/armv8/fsl-layerscape/cpu.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/arm/cpu/armv8/fsl-layerscape/cpu.c b/arch/arm/cpu/armv8/fsl-layerscape/cpu.c
index 752ccb0..f000a6a 100644
--- a/arch/arm/cpu/armv8/fsl-layerscape/cpu.c
+++ b/arch/arm/cpu/armv8/fsl-layerscape/cpu.c
@@ -146,11 +146,14 @@ static inline void final_mmu_setup(void)
 	set_ttbr_tcr_mair(el, gd->arch.tlb_addr, get_tcr(el, NULL, NULL),
 			  MEMORY_ATTRIBUTES);
 	/*
-	 * MMU is already enabled, just need to invalidate TLB to load the
+	 * EL3 MMU is already enabled, just need to invalidate TLB to load the
 	 * new table. The new table is compatible with the current table, if
 	 * MMU somehow walks through the new table before invalidation TLB,
 	 * it still works. So we don't need to turn off MMU here.
+	 * When EL2 MMU table is created by calling this function, MMU needs
+	 * to be enabled.
 	 */
+	set_sctlr(get_sctlr() | CR_M);
 }
 
 u64 get_page_table_size(void)
-- 
2.7.4