DMA_GLOBAL_POOL config may be enabled for platforms where global pool is
not supported because a generic defconfig is expected to boot on different
platforms. Specifically, some RISC-V platforms may use global pool for
non-coherent devices while some other platforms are completely coherent.
However, it is expected that single kernel image must boot on all the
platforms.

Continue the dma direct allocation if a allocation from global pool failed.
This indicates that the platform is relying on some other method (direct
remap) or just have coherent devices.

Signed-off-by: Atish Patra <[email protected]>
---
 kernel/dma/direct.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index d1d0258ed6d0..984ea776f099 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -161,8 +161,11 @@ void *dma_direct_alloc(struct device *dev, size_t size,
                return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
 
        if (IS_ENABLED(CONFIG_DMA_GLOBAL_POOL) &&
-           !dev_is_dma_coherent(dev))
-               return dma_alloc_from_global_coherent(dev, size, dma_handle);
+           !dev_is_dma_coherent(dev)) {
+               ret = dma_alloc_from_global_coherent(dev, size, dma_handle);
+               if (ret)
+                       return ret;
+       }
 
        /*
         * Remapping or decrypting memory may block. If either is required and
-- 
2.31.1

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