[7/8] arm64: update arch_zone_dma_bits to fine tune dma-direct min mask
diff mbox series

Message ID 20190731154752.16557-8-nsaenzjulienne@suse.de
State New, archived
Headers show
Series
  • Raspberry Pi 4 DMA addressing support
Related show

Commit Message

Nicolas Saenz Julienne July 31, 2019, 3:47 p.m. UTC
With the introduction of ZONE_DMA in arm64 devices are not forced to
support 32 bit DMA masks. We have to inform dma-direct of this
limitation whenever it happens.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
---

 arch/arm64/mm/init.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

Patch
diff mbox series

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index f5279ef85756..b809f3259340 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -22,6 +22,7 @@ 
 #include <linux/of_fdt.h>
 #include <linux/dma-mapping.h>
 #include <linux/dma-contiguous.h>
+#include <linux/dma-direct.h>
 #include <linux/efi.h>
 #include <linux/swiotlb.h>
 #include <linux/vmalloc.h>
@@ -439,10 +440,14 @@  void __init arm64_memblock_init(void)
 
 	early_init_fdt_scan_reserved_mem();
 
-	if (IS_ENABLED(CONFIG_ZONE_DMA))
+	if (IS_ENABLED(CONFIG_ZONE_DMA)) {
 		arm64_dma_phys_limit = max_zone_dma_phys();
-	else
+
+		if (arm64_dma_phys_limit)
+			arch_zone_dma_bits = ilog2(arm64_dma_phys_limit) + 1;
+	} else {
 		arm64_dma_phys_limit = 0;
+	}
 
 	/* 4GB maximum for 32-bit only capable devices */
 	if (IS_ENABLED(CONFIG_ZONE_DMA32))