[PATCH 07/12] iommu/arm-smmu: Factor out mmu-masters handling
Robin Murphy
robin.murphy at arm.com
Mon Feb 29 05:46:16 PST 2016
Reorder the SMMU probe routine slightly to separate probing and
configuring the SMMU itself from processing the mmu-masters property,
and break the handling of the latter out into self-contained functions.
In preparation for changes to come, the failure mode is changed slightly
such that instead of a malformed mmu-masters property aborting the whole
SMMU device probe, we instead roll back any association with those
master devices and let the SMMU itself continue without them.
Signed-off-by: Robin Murphy <robin.murphy at arm.com>
---
drivers/iommu/arm-smmu.c | 88 ++++++++++++++++++++++++++----------------------
1 file changed, 48 insertions(+), 40 deletions(-)
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 514ae2d..6f7c531 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -465,7 +465,6 @@ 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)
{
int i;
@@ -473,20 +472,20 @@ static int register_smmu_master(struct arm_smmu_device *smmu,
master = find_smmu_master(smmu, masterspec->np);
if (master) {
- dev_err(dev,
+ dev_err(smmu->dev,
"rejecting multiple registrations for master device %s\n",
masterspec->np->name);
return -EBUSY;
}
if (masterspec->args_count > MAX_MASTER_STREAMIDS) {
- dev_err(dev,
+ dev_err(smmu->dev,
"reached maximum number (%d) of stream IDs for master device %s\n",
MAX_MASTER_STREAMIDS, masterspec->np->name);
return -ENOSPC;
}
- master = devm_kzalloc(dev, sizeof(*master), GFP_KERNEL);
+ master = devm_kzalloc(smmu->dev, sizeof(*master), GFP_KERNEL);
if (!master)
return -ENOMEM;
@@ -498,7 +497,7 @@ static int register_smmu_master(struct arm_smmu_device *smmu,
if (!(smmu->features & ARM_SMMU_FEAT_STREAM_MATCH) &&
(streamid >= smmu->num_mapping_groups)) {
- dev_err(dev,
+ dev_err(smmu->dev,
"stream ID for master device %s greater than maximum allowed (%d)\n",
masterspec->np->name, smmu->num_mapping_groups);
return -ERANGE;
@@ -1730,14 +1729,53 @@ static const struct of_device_id arm_smmu_of_match[] = {
};
MODULE_DEVICE_TABLE(of, arm_smmu_of_match);
+static void arm_smmu_remove_mmu_masters(struct arm_smmu_device *smmu)
+{
+ struct arm_smmu_master *master;
+ struct rb_node *node, *tmp;
+
+ node = rb_first(&smmu->masters);
+ while (node) {
+ tmp = node;
+ node = rb_next(node);
+ master = container_of(tmp, struct arm_smmu_master, node);
+
+ rb_erase(tmp, &smmu->masters);
+ of_node_put(master->of_node);
+ devm_kfree(smmu->dev, master);
+ }
+}
+
+static int arm_smmu_probe_mmu_masters(struct arm_smmu_device *smmu)
+{
+ struct of_phandle_args masterspec;
+ int err, i = 0;
+
+ while (!of_parse_phandle_with_args(smmu->dev->of_node, "mmu-masters",
+ "#stream-id-cells", i,
+ &masterspec)) {
+ err = register_smmu_master(smmu, &masterspec);
+ if (err)
+ break;
+ i++;
+ }
+
+ if (err) {
+ dev_err(smmu->dev, "failed to register mmu-masters\n");
+ arm_smmu_remove_mmu_masters(smmu);
+ } else if (i) {
+ dev_info(smmu->dev, "registered %d mmu-masters\n", i);
+ }
+
+ return err;
+}
+
static int arm_smmu_device_dt_probe(struct platform_device *pdev)
{
const struct of_device_id *of_id;
struct resource *res;
struct arm_smmu_device *smmu;
struct device *dev = &pdev->dev;
- struct rb_node *node;
- struct of_phandle_args masterspec;
int num_irqs, i, err;
smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL);
@@ -1796,22 +1834,6 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev)
if (err)
return err;
- i = 0;
- smmu->masters = RB_ROOT;
- while (!of_parse_phandle_with_args(dev->of_node, "mmu-masters",
- "#stream-id-cells", i,
- &masterspec)) {
- err = register_smmu_master(smmu, dev, &masterspec);
- if (err) {
- dev_err(dev, "failed to add master %s\n",
- masterspec.np->name);
- goto out_put_masters;
- }
-
- i++;
- }
- dev_notice(dev, "registered %d master devices\n", i);
-
parse_driver_options(smmu);
if (smmu->version > ARM_SMMU_V1 &&
@@ -1819,8 +1841,7 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev)
dev_err(dev,
"found only %d context interrupt(s) but %d required\n",
smmu->num_context_irqs, smmu->num_context_banks);
- err = -ENODEV;
- goto out_put_masters;
+ return -ENODEV;
}
for (i = 0; i < smmu->num_global_irqs; ++i) {
@@ -1837,6 +1858,7 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev)
}
platform_set_drvdata(pdev, smmu);
+ arm_smmu_probe_mmu_masters(smmu);
INIT_LIST_HEAD(&smmu->list);
spin_lock(&arm_smmu_devices_lock);
list_add(&smmu->list, &arm_smmu_devices);
@@ -1848,14 +1870,6 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev)
out_free_irqs:
while (i--)
free_irq(smmu->irqs[i], smmu);
-
-out_put_masters:
- for (node = rb_first(&smmu->masters); node; node = rb_next(node)) {
- struct arm_smmu_master *master
- = container_of(node, struct arm_smmu_master, node);
- of_node_put(master->of_node);
- }
-
return err;
}
@@ -1863,21 +1877,15 @@ static int arm_smmu_device_remove(struct platform_device *pdev)
{
struct arm_smmu_device *smmu = platform_get_drvdata(pdev);
int i;
- struct rb_node *node;
if (!smmu)
return -ENODEV;
+ arm_smmu_remove_mmu_masters(smmu);
spin_lock(&arm_smmu_devices_lock);
list_del(&smmu->list);
spin_unlock(&arm_smmu_devices_lock);
- for (node = rb_first(&smmu->masters); node; node = rb_next(node)) {
- struct arm_smmu_master *master
- = container_of(node, struct arm_smmu_master, node);
- of_node_put(master->of_node);
- }
-
if (!bitmap_empty(smmu->context_map, ARM_SMMU_MAX_CBS))
dev_err(&pdev->dev, "removing device with active domains!\n");
--
2.7.2.333.g70bd996.dirty
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