mtd: nand: pxa3xx: fix build on ARM64

In preparation to enable ARCH_MMP on ARM64, a couple of fixes are needed
to build the pxa3xx_nand driver:

Legacy DMA will only used on ARM, so also make it condtional on
CONFIG_ARM.
__raw_{read,write}sl are not available on ARM64 or generically, so use
the readsl/writesl variants instead. Somewhat inconsistently,
{read,write}sl are inherently non-swapping with the generic version
using __raw_{read,write}l.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: linux-mtd@lists.infradead.org
[Brian: added one more __raw_readsl -> readsl]
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

drivers/mtd/nand/pxa3xx_nand.c

@@ -29,7 +29,7 @@
 #include <linux/of_device.h>
 #include <linux/of_mtd.h>
 
-#if defined(CONFIG_ARCH_PXA) || defined(CONFIG_ARCH_MMP)
+#if defined(CONFIG_ARM) && (defined(CONFIG_ARCH_PXA) || defined(CONFIG_ARCH_MMP))
 #define ARCH_HAS_DMA
 #endif
 
@@ -496,7 +496,7 @@ static void drain_fifo(struct pxa3xx_nand_info *info, void *data, int len)
 		 * the polling on the last read.
 		 */
 		while (len > 8) {
-			__raw_readsl(info->mmio_base + NDDB, data, 8);
+			readsl(info->mmio_base + NDDB, data, 8);
 
 			ret = readl_relaxed_poll_timeout(info->mmio_base + NDSR, val,
 							 val & NDSR_RDDREQ, 1000, 5000);
@@ -511,7 +511,7 @@ static void drain_fifo(struct pxa3xx_nand_info *info, void *data, int len)
 		}
 	}
 
-	__raw_readsl(info->mmio_base + NDDB, data, len);
+	readsl(info->mmio_base + NDDB, data, len);
 }
 
 static void handle_data_pio(struct pxa3xx_nand_info *info)
@@ -520,14 +520,14 @@ static void handle_data_pio(struct pxa3xx_nand_info *info)
 
 	switch (info->state) {
 	case STATE_PIO_WRITING:
-		__raw_writesl(info->mmio_base + NDDB,
-			      info->data_buff + info->data_buff_pos,
-			      DIV_ROUND_UP(do_bytes, 4));
+		writesl(info->mmio_base + NDDB,
+			info->data_buff + info->data_buff_pos,
+			DIV_ROUND_UP(do_bytes, 4));
 
 		if (info->oob_size > 0)
-			__raw_writesl(info->mmio_base + NDDB,
-				      info->oob_buff + info->oob_buff_pos,
-				      DIV_ROUND_UP(info->oob_size, 4));
+			writesl(info->mmio_base + NDDB,
+				info->oob_buff + info->oob_buff_pos,
+				DIV_ROUND_UP(info->oob_size, 4));
 		break;
 	case STATE_PIO_READING:
 		drain_fifo(info,
@@ -1628,8 +1628,7 @@ static int alloc_nand_resource(struct platform_device *pdev)
 	info->pdev = pdev;
 	info->variant = pxa3xx_nand_get_variant(pdev);
 	for (cs = 0; cs < pdata->num_cs; cs++) {
-		mtd = (struct mtd_info *)((unsigned int)&info[1] +
-		      (sizeof(*mtd) + sizeof(*host)) * cs);
+		mtd = (void *)&info[1] + (sizeof(*mtd) + sizeof(*host)) * cs;
 		chip = (struct nand_chip *)(&mtd[1]);
 		host = (struct pxa3xx_nand_host *)chip;
 		info->host[cs] = host;