On 05/22/2018 10:10 AM, Arnd Bergmann wrote: > On Tue, May 22, 2018 at 12:05 AM, Marek Vasut <marek.vasut@xxxxxxxxx> wrote: >> From: Phil Edworthy <phil.edworthy@xxxxxxxxxxx> >> >> The PCIe DMA controller on RCar Gen2 and earlier is on 32bit bus, >> so limit the DMA range to 32bit. >> >> Signed-off-by: Phil Edworthy <phil.edworthy@xxxxxxxxxxx> >> Signed-off-by: Marek Vasut <marek.vasut+renesas@xxxxxxxxx> >> Cc: Arnd Bergmann <arnd@xxxxxxxx> >> Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> >> Cc: Phil Edworthy <phil.edworthy@xxxxxxxxxxx> >> Cc: Simon Horman <horms+renesas@xxxxxxxxxxxx> >> Cc: Wolfram Sang <wsa@xxxxxxxxxxxxx> >> Cc: linux-renesas-soc@xxxxxxxxxxxxxxx >> To: linux-pci@xxxxxxxxxxxxxxx >> --- >> NOTE: I'm aware of https://patchwork.kernel.org/patch/9495895/ , but the >> discussion seems to have gone way off, so I'm sending this as a >> RFC. Any feedback on how to do this limiting properly would be nice. > > Doing it in the driver is clearly not appropriate, we must do this in > common code. If I remember correctly, it's specifically ARM64 that is > broken here, it incorrectly allows setting a DMA mask to 64 bit > when that is not available. Yep, that's correct. ARM64 with devices mapping tremendous amounts of memory. So did anything change since that discussion references in the NOTE? -- Best regards, Marek Vasut
