[PATCH 1/1] dma-contiguous: return early for dt case in dma_contiguous_reserve

[Dong Aisheng]

dma_contiguous_reserve() aims to support cmdline case for CMA memory
reserve. But if users define reserved memory in DT,
'dma_contiguous_default_area' will not be 0, then it's meaningless
to continue to run dma_contiguous_reserve(). So we return early
if detect 'dma_contiguous_default_area' is unzero.

Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Signed-off-by: Dong Aisheng <aisheng.dong@xxxxxxx>
---
 kernel/dma/contiguous.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c
index 3d63d91cba5c..ebade9f43eff 100644
--- a/kernel/dma/contiguous.c
+++ b/kernel/dma/contiguous.c
@@ -171,6 +171,9 @@ void __init dma_contiguous_reserve(phys_addr_t limit)
 	phys_addr_t selected_limit = limit;
 	bool fixed = false;
 
+	if (dma_contiguous_default_area)
+		return;
+
 	pr_debug("%s(limit %08lx)\n", __func__, (unsigned long)limit);
 
 	if (size_cmdline != -1) {
@@ -191,7 +194,7 @@ void __init dma_contiguous_reserve(phys_addr_t limit)
 #endif
 	}
 
-	if (selected_size && !dma_contiguous_default_area) {
+	if (selected_size) {
 		pr_debug("%s: reserving %ld MiB for global area\n", __func__,
 			 (unsigned long)selected_size / SZ_1M);
 
-- 
2.25.1