crypto: mxs-dcp - Align the bounce buffers

The DCP needs the bounce buffers, DMA descriptors and result buffers aligned
to 64 bytes (yet another hardware limitation). Make sure they are aligned by
properly aligning the structure which contains them during allocation.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/mxs-dcp.c

@@ -29,6 +29,8 @@
 #define DCP_MAX_CHANS	4
 #define DCP_BUF_SZ	PAGE_SIZE
 
+#define DCP_ALIGNMENT	64
+
 /* DCP DMA descriptor. */
 struct dcp_dma_desc {
 	uint32_t	next_cmd_addr;
@@ -947,12 +949,16 @@ static int mxs_dcp_probe(struct platform_device *pdev)
 	}
 
 	/* Allocate coherent helper block. */
-	sdcp->coh = devm_kzalloc(dev, sizeof(*sdcp->coh), GFP_KERNEL);
+	sdcp->coh = devm_kzalloc(dev, sizeof(*sdcp->coh) + DCP_ALIGNMENT,
+				   GFP_KERNEL);
 	if (!sdcp->coh) {
 		ret = -ENOMEM;
 		goto err_mutex;
 	}
 
+	/* Re-align the structure so it fits the DCP constraints. */
+	sdcp->coh = PTR_ALIGN(sdcp->coh, DCP_ALIGNMENT);
+
 	/* Restart the DCP block. */
 	ret = stmp_reset_block(sdcp->base);
 	if (ret)