37f7860602
Single page and coherent memory blocks can use different DMA masks when the macb accesses physical memory directly. The kernel is clever enough to allocate pages that fit into the requested address width. When using the ARM SMMU, the DMA mask must be the same for single pages and big coherent memory blocks. Otherwise the translation tables turn into one big mess. [ 74.959909] macb ff0e0000.ethernet eth0: DMA bus error: HRESP not OK [ 74.959989] arm-smmu fd800000.smmu: Unhandled context fault: fsr=0x402, iova=0x3165687460, fsynr=0x20001, cbfrsynra=0x877, cb=1 [ 75.173939] macb ff0e0000.ethernet eth0: DMA bus error: HRESP not OK [ 75.173955] arm-smmu fd800000.smmu: Unhandled context fault: fsr=0x402, iova=0x3165687460, fsynr=0x20001, cbfrsynra=0x877, cb=1 Since using the same DMA mask does not hurt direct 1:1 physical memory mappings, this commit always aligns DMA and coherent masks. Signed-off-by: Marc St-Amand <mstamand@ciena.com> Signed-off-by: Harini Katakam <harini.katakam@xilinx.com> Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> Tested-by: Conor Dooley <conor.dooley@microchip.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.