From mboxrd@z Thu Jan 1 00:00:00 1970 From: Will Deacon Subject: Re: [PATCH 1/5] iommu/arm-smmu: Introduce driver option handling Date: Tue, 8 Oct 2013 16:06:13 +0100 Message-ID: <20131008150613.GC21189@mudshark.cambridge.arm.com> References: <1381224444-27303-1-git-send-email-andreas.herrmann@calxeda.com> <1381224444-27303-2-git-send-email-andreas.herrmann@calxeda.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1381224444-27303-2-git-send-email-andreas.herrmann-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Andreas Herrmann Cc: "iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org" , Rob Herring , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" List-Id: iommu@lists.linux-foundation.org On Tue, Oct 08, 2013 at 10:27:20AM +0100, Andreas Herrmann wrote: > Introduce handling of driver options. Options are set based on DT > information when probing an SMMU device. The first option introduced > is "arm,smmu-isolate-devices". (It will be used in the bus notifier > block.) > > Signed-off-by: Andreas Herrmann > --- > drivers/iommu/arm-smmu.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 49 insertions(+) > > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > index b632bcd..b127f0f 100644 > --- a/drivers/iommu/arm-smmu.c > +++ b/drivers/iommu/arm-smmu.c > @@ -348,6 +348,7 @@ struct arm_smmu_device { > #define ARM_SMMU_FEAT_TRANS_S2 (1 << 3) > #define ARM_SMMU_FEAT_TRANS_NESTED (1 << 4) > u32 features; > + u32 options; This should be enum arm_smmu_option. Also, we should probably be consistent between the options and features (i.e. either use an enum for each of them, or just stick to #defines for both). > int version; > > u32 num_context_banks; > @@ -398,6 +399,52 @@ struct arm_smmu_domain { > static DEFINE_SPINLOCK(arm_smmu_devices_lock); > static LIST_HEAD(arm_smmu_devices); > > +/* driver options */ > +enum arm_smmu_option { > + ISOLATE_DEVICES = 0, > + OPTION_MAX, > +}; > + > +struct arm_smmu_option_prop { > + enum arm_smmu_option opt; > + const char *prop; > +}; > + > +static struct arm_smmu_option_prop arm_smmu_options [] = { > + { ISOLATE_DEVICES, "arm,smmu-isolate-devices" }, > + { OPTION_MAX, NULL}, > +}; > + > +static inline int arm_smmu_has_option(struct arm_smmu_device *smmu, > + enum arm_smmu_option opt) > +{ > + return (smmu->options & (1 << opt)); > +} > + > +static inline void arm_smmu_set_option(struct arm_smmu_device *smmu, > + enum arm_smmu_option opt) > +{ > + smmu->options |= (1 << opt); > +} > + > +static inline void arm_smmu_clear_option(struct arm_smmu_device *smmu, > + enum arm_smmu_option opt) > +{ > + smmu->options &= ~(1 << opt); > +} These three functions are a bit over-engineered! We have things like __set_bit if you really want to use helpers. Will