On Tue, Sep 24, 2013 at 04:07:00PM +0100, Andreas Herrmann wrote: > arm-smmu= arm-smmu driver option > > off Disable arm-smmu driver (ie. ignore available SMMUs) > > force_isolation > Try to attach each master device on every SMMU to a > separate iommu_domain. > > Default is that driver detects SMMUs but no translation is configured > (transactions just bypass translation process). > > Signed-off-by: Andreas Herrmann <[email protected]> > --- > drivers/iommu/arm-smmu.c | 26 ++++++++++++++++++++++++++ > 1 file changed, 26 insertions(+) > > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > index 3eb2259..251564e 100644 > --- a/drivers/iommu/arm-smmu.c > +++ b/drivers/iommu/arm-smmu.c > @@ -399,6 +399,9 @@ struct arm_smmu_domain { > static DEFINE_SPINLOCK(arm_smmu_devices_lock); > static LIST_HEAD(arm_smmu_devices); > > +static bool arm_smmu_disabled; > +static bool arm_smmu_force_isolation; > + > static struct arm_smmu_master *find_smmu_master(struct arm_smmu_device *smmu, > struct device_node *dev_node) > { > @@ -1837,6 +1840,9 @@ static int arm_smmu_device_dt_probe(struct > platform_device *pdev) > struct of_phandle_args masterspec; > int num_irqs, i, err; > > + if (arm_smmu_disabled) > + return -ENODEV; > + > smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL); > if (!smmu) { > dev_err(dev, "failed to allocate arm_smmu_device\n"); > @@ -2022,6 +2028,23 @@ static struct platform_driver arm_smmu_driver = { > .remove = arm_smmu_device_remove, > }; > > +static int __init arm_smmu_parse_options(char *str) > +{ > + if (*str) { > + str++; > + if (!strncmp(str, "off", 3)) > + arm_smmu_disabled = true; > + else if(!strncmp(str, "force_isolation", 15)) > + arm_smmu_force_isolation = true; > + else { > + pr_warn("arm_smmu: invalid parameter (\"%s\")\n", str); > + return 0; > + } > + } > + return 1; > +} > +__setup("arm-smmu", arm_smmu_parse_options);
If this is going to be a common function for IOMMUs, let's instead move the command-line parsing out into the generic IOMMU layer, then have an optional callback into the low-level IOMMU driver for enabling/disabling it. Will _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
