[PATCH] arm: layerscape: Check zero size memory bank before lmb_add

[Ye Li]

In layerspace's lmb_arch_add_memory implementation, all memory bank
are added to lmb, even some is with zero size. This will cause lmb
treating it as overlap with available memory by lmb_addrs_overlap
and merge with available memory. Finally causing available memory
start address changed to 0.

For example, on LX2160, before zero memory bank added to lmb, there
are two available memory regions:
  - region 0, start 0x80000000, size 0x7be00000
  - region 1, start 0x2080000000, size 0x700000000
After zero size memory bank added, merge to one region:
  - region 0, start 0, size 0x2780000000
This wrong new region causes efi_memory_init issue when allocating bounce
buffer because of conflict address (with uboot reserved) is allocated.

Signed-off-by: Ye Li <ye.li at nxp.com>
---
 arch/arm/cpu/armv8/fsl-layerscape/cpu.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm/cpu/armv8/fsl-layerscape/cpu.c b/arch/arm/cpu/armv8/fsl-layerscape/cpu.c
index cfbaa475701..7f0cb28f52d 100644
--- a/arch/arm/cpu/armv8/fsl-layerscape/cpu.c
+++ b/arch/arm/cpu/armv8/fsl-layerscape/cpu.c
@@ -1549,7 +1549,8 @@ void lmb_arch_add_memory(void)
 		    gd->arch.resv_ram < ram_start + ram_size)
 			ram_size = gd->arch.resv_ram - ram_start;
 #endif
-		lmb_add(ram_start, ram_size);
+		if (ram_size > 0)
+			lmb_add(ram_start, ram_size);
 	}
 }
 #endif
-- 
2.37.1