Hi Joerg, On Tue, Mar 22, 2016 at 06:58:29PM +0100, Joerg Roedel wrote: > From: Joerg Roedel <[email protected]> > > Remove the usage of of_parse_phandle_with_args() and replace > it by the phandle-iterator implementation so that we can > parse out all of the potentially present 128 stream-ids. > > Signed-off-by: Joerg Roedel <[email protected]> > --- > drivers/iommu/arm-smmu.c | 28 ++++++++++++++++++++++------ > 1 file changed, 22 insertions(+), 6 deletions(-) > > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > index 59ee4b8..413bd64 100644 > --- a/drivers/iommu/arm-smmu.c > +++ b/drivers/iommu/arm-smmu.c > @@ -48,7 +48,7 @@ > #include "io-pgtable.h" > > /* Maximum number of stream IDs assigned to a single device */ > -#define MAX_MASTER_STREAMIDS MAX_PHANDLE_ARGS > +#define MAX_MASTER_STREAMIDS 128 > > /* Maximum number of context banks per SMMU */ > #define ARM_SMMU_MAX_CBS 128 > @@ -349,6 +349,12 @@ struct arm_smmu_domain { > struct iommu_domain domain; > }; > > +struct arm_smmu_phandle_args { > + struct device_node *np; > + int args_count; > + uint32_t args[MAX_MASTER_STREAMIDS]; > +}; > + > static struct iommu_ops arm_smmu_ops; > > static DEFINE_SPINLOCK(arm_smmu_devices_lock); > @@ -458,7 +464,7 @@ static int insert_smmu_master(struct arm_smmu_device > *smmu, > > static int register_smmu_master(struct arm_smmu_device *smmu, > struct device *dev, > - struct of_phandle_args *masterspec) > + struct arm_smmu_phandle_args *masterspec) > { > int i; > struct arm_smmu_master *master; > @@ -1716,7 +1722,8 @@ static int arm_smmu_device_dt_probe(struct > platform_device *pdev) > struct arm_smmu_device *smmu; > struct device *dev = &pdev->dev; > struct rb_node *node; > - struct of_phandle_args masterspec; > + struct of_phandle_iterator it; > + struct arm_smmu_phandle_args masterspec; > int num_irqs, i, err; > > smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL); > @@ -1777,9 +1784,14 @@ static int arm_smmu_device_dt_probe(struct > platform_device *pdev) > > i = 0; > smmu->masters = RB_ROOT; > - while (!of_parse_phandle_with_args(dev->of_node, "mmu-masters", > - "#stream-id-cells", i, > - &masterspec)) { > + > + of_for_each_phandle(&it, err, dev->of_node, > + "mmu-masters", "#stream-id-cells", 0) { > + int count = of_phandle_iterator_args(&it, masterspec.args, > + MAX_MASTER_STREAMIDS); > + masterspec.np = of_node_get(it.node); > + masterspec.args_count = count; > + > err = register_smmu_master(smmu, dev, &masterspec); > if (err) { > dev_err(dev, "failed to add master %s\n", > @@ -1789,6 +1801,10 @@ static int arm_smmu_device_dt_probe(struct > platform_device *pdev) > > i++; > } > + > + if (i == 0) > + goto out_put_masters;
I'm confused by this hunk. If i == 0, then we shouldn't have registered any masters and therefore out_put_masters won't have anything to do. In fact, I'm not completely clear on how the of_node refcounting interacts with your iterators. Does the iterator put the node after you call the "next" function, or does it increment each thing exactly once? Will
