From 1a8e1cef7603e218339ac63cb3178b25554524e5 Mon Sep 17 00:00:00 2001 From: Nicolas Saenz Julienne Date: Wed, 11 Sep 2019 20:25:45 +0200 Subject: arm64: use both ZONE_DMA and ZONE_DMA32 So far all arm64 devices have supported 32 bit DMA masks for their peripherals. This is not true anymore for the Raspberry Pi 4 as most of it's peripherals can only address the first GB of memory on a total of up to 4 GB. This goes against ZONE_DMA32's intent, as it's expected for ZONE_DMA32 to be addressable with a 32 bit mask. So it was decided to re-introduce ZONE_DMA in arm64. ZONE_DMA will contain the lower 1G of memory, which is currently the memory area addressable by any peripheral on an arm64 device. ZONE_DMA32 will contain the rest of the 32 bit addressable memory. Signed-off-by: Nicolas Saenz Julienne Reviewed-by: Catalin Marinas Signed-off-by: Catalin Marinas --- arch/arm64/Kconfig | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'arch/arm64/Kconfig') diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 950a56b71ff0..1b6ea5a9d1a6 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -266,6 +266,10 @@ config GENERIC_CSUM config GENERIC_CALIBRATE_DELAY def_bool y +config ZONE_DMA + bool "Support DMA zone" if EXPERT + default y + config ZONE_DMA32 bool "Support DMA32 zone" if EXPERT default y -- cgit v1.2.3-59-g8ed1b