From: will.deacon@arm.com (Will Deacon) Date: Mon, 26 Feb 2018 18:04:56 +0000 Subject: [PATCH v2 1/4] iommu/arm-smmu-v3: Clean up address masking In-Reply-To: <24f90689e35a90a337601943a48902a7ab6a7c4d.1512038236.git.robin.murphy@arm.com> References: <24f90689e35a90a337601943a48902a7ab6a7c4d.1512038236.git.robin.murphy@arm.com> Message-ID: <20180226180455.GB26147@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Robin, On Thu, Dec 14, 2017 at 04:58:50PM +0000, Robin Murphy wrote: > Before trying to add the SMMUv3.1 support for 52-bit addresses, make > things bearable by cleaning up the various address mask definitions to > use GENMASK_ULL() consistently. The fact that doing so reveals (and > fixes) a latent off-by-one in Q_BASE_ADDR_MASK only goes to show what a > jolly good idea it is... > > Tested-by: Nate Watterson > Signed-off-by: Robin Murphy > --- > > v2: Clean up one more now-unnecessary linewrap > > drivers/iommu/arm-smmu-v3.c | 53 ++++++++++++++++++--------------------------- > 1 file changed, 21 insertions(+), 32 deletions(-) Whilst I agree that using GENMASK is better, this patch does mean that the driver is (more) inconsistent with its _MASK terminology in that you can't generally tell whether a definition that ends in _MASK is shifted or not, and this isn't even consistent for fields within the same register. Should we be using GENMASK/BIT for all fields instead and removing all of the _SHIFT definitions? Will