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From:   Will Deacon <will@kernel.org>
To:     iommu@lists.linux-foundation.org
Cc:     linux-kernel@vger.kernel.org, Will Deacon <will@kernel.org>,
        Guenter Roeck <linux@roeck-us.net>,
        Claire Chang <tientzu@chromium.org>,
        Christoph Hellwig <hch@lst.de>,
        Robin Murphy <robin.murphy@arm.com>,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        Nathan Chancellor <nathan@kernel.org>
Subject: [PATCH v2 1/4] of: Return success from of_dma_set_restricted_buffer() when !OF_ADDRESS
Date:   Tue, 20 Jul 2021 14:38:23 +0100
Message-Id: <20210720133826.9075-2-will@kernel.org>
In-Reply-To: <20210720133826.9075-1-will@kernel.org>
References: <20210720133826.9075-1-will@kernel.org>
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When CONFIG_OF_ADDRESS=n, of_dma_set_restricted_buffer() returns -ENODEV
and breaks the boot for sparc[64] machines. Return 0 instead, since the
function is essentially a glorified NOP in this configuration.

Cc: Claire Chang <tientzu@chromium.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210702030807.GA2685166@roeck-us.net
Fixes: fec9b625095f ("of: Add plumbing for restricted DMA pool")
Signed-off-by: Will Deacon <will@kernel.org>
---
 drivers/of/of_private.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h
index 376462798f7e..f557bd22b0cf 100644
--- a/drivers/of/of_private.h
+++ b/drivers/of/of_private.h
@@ -173,7 +173,8 @@ static inline int of_dma_get_range(struct device_node *np,
 static inline int of_dma_set_restricted_buffer(struct device *dev,
 					       struct device_node *np)
 {
-	return -ENODEV;
+	/* Do nothing, successfully. */
+	return 0;
 }
 #endif
 
-- 
2.32.0.402.g57bb445576-goog