diff options
| author |   Alexey Brodkin <abrodkin@synopsys.com> | 2016-04-27 16:59:50 +0300 |
|---|---|---|
| committer | Alexey Brodkin <abrodkin@synopsys.com> | 2016-04-29 14:34:13 +0300 |
| commit | cb2ad5e5339c5122166265cea579cc6a356d46de (patch) | |
| tree | bd45a96027bc8f8f1e2e0245bd342978ad03fb7c /arch/arc/boot/dts/axc003_idu.dtsi | |
| parent | drm/arcpgu: use dedicated memory area for frame buffer (diff) | |
| download | linux-dev-cb2ad5e5339c5122166265cea579cc6a356d46de.tar.xz linux-dev-cb2ad5e5339c5122166265cea579cc6a356d46de.zip | |
ARC: [axs10x] Specify reserved memory for frame buffer
Allocation of a frame buffer memory in a special memory region
allows bypassing of so-called IO Coherency aperture
which is typically set as a range 0x8z-0xAz.
I.e. all data traffic to PGU bypasses IO Coherency block
and saves its bandwidth for other peripherals.
Even though for AXS101 (which sorts ARC770 CPU) IOC is not
an option for a sake of keeping one DT description for the
base-board (axs10x_mb.dtsi) we're still defining reserved
memory location in the very end of DDR.
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Cc: devicetree@vger.kernel.org
Diffstat (limited to 'arch/arc/boot/dts/axc003_idu.dtsi')
| -rw-r--r-- | arch/arc/boot/dts/axc003_idu.dtsi | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/arch/arc/boot/dts/axc003_idu.dtsi b/arch/arc/boot/dts/axc003_idu.dtsi index 06a9f294a2e6..df9ddb623bfe 100644 --- a/arch/arc/boot/dts/axc003_idu.dtsi +++ b/arch/arc/boot/dts/axc003_idu.dtsi @@ -123,4 +123,18 @@ device_type = "memory"; reg = <0x80000000 0x20000000>; /* 512MiB */ }; + + reserved-memory { + #address-cells = <1>; + #size-cells = <1>; + ranges; + /* + * Move frame buffer out of IOC aperture (0x8z-0xAz). + */ + frame_buffer: frame_buffer@be000000 { + compatible = "shared-dma-pool"; + reg = <0xbe000000 0x2000000>; + no-map; + }; + }; }; |