[RFC PATCH 06/11] drivers: iommu: make of_xlate() interface DT agnostic
Lorenzo Pieralisi
lorenzo.pieralisi at arm.com
Thu Apr 14 10:25:38 PDT 2016
On systems booting with ACPI, the IOMMU drivers require the same
kind of id mapping carried out with a DT tree through the of_xlate()
API in order to map devices identifiers to IOMMU ones.
On ACPI systems, since DT nodes are not present (ie struct
device.of_node == NULL), to identify the device requiring the translation
the struct device_node (and the structure used to pass translation
information - struct of_phandle_args - that contains a struct device_node)
cannot be used, so a generic translation structure to be used for IOMMU
mapping should be defined, based on the firmware agnostic fwnode_handle
type.
This patch mechanically refactors/renames the of_xlate API to make
it DT agnostic, by declaring a new type (struct iommu_fwspec), that
allows the kernel to pass a device identifier (fwnode - which can
represent either a DT node or an IOMMU FW node) and by changing the
of_xlate signature so that it does not take anymore the DT specific
of_phandle_args argument and replaces it with the DT agnostic
iommu_fwspec one.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
Cc: Matthias Brugger <matthias.bgg at gmail.com>
Cc: Will Deacon <will.deacon at arm.com>
Cc: Hanjun Guo <hanjun.guo at linaro.org>
Cc: Rob Herring <robh+dt at kernel.org>
Cc: Krzysztof Kozlowski <k.kozlowski at samsung.com>
Cc: Robin Murphy <robin.murphy at arm.com>
Cc: Tomasz Nowicki <tn at semihalf.com>
Cc: Joerg Roedel <joro at 8bytes.org>
Cc: Marek Szyprowski <m.szyprowski at samsung.com>
---
drivers/iommu/arm-smmu.c | 12 +++++++-----
drivers/iommu/exynos-iommu.c | 11 +++++++----
drivers/iommu/mtk_iommu.c | 13 ++++++++-----
drivers/iommu/of_iommu.c | 20 ++++++++++++++++++--
include/linux/iommu.h | 24 ++++++++++++++++++++----
5 files changed, 60 insertions(+), 20 deletions(-)
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 6c42770..84bcff7 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1440,18 +1440,20 @@ out_unlock:
return ret;
}
-static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args)
+static int arm_smmu_fw_xlate(struct device *dev, struct iommu_fwspec *args)
{
struct arm_smmu_device *smmu;
- struct platform_device *smmu_pdev;
+ struct platform_device *smmu_pdev = NULL;
+
+ if (is_of_node(args->fwnode))
+ smmu_pdev = of_find_device_by_node(to_of_node(args->fwnode));
- smmu_pdev = of_find_device_by_node(args->np);
if (!smmu_pdev)
return -ENODEV;
smmu = platform_get_drvdata(smmu_pdev);
- return arm_smmu_add_dev_streamid(smmu, dev, args->args[0]);
+ return arm_smmu_add_dev_streamid(smmu, dev, args->param[0]);
}
static struct iommu_ops arm_smmu_ops = {
@@ -1468,7 +1470,7 @@ static struct iommu_ops arm_smmu_ops = {
.device_group = arm_smmu_device_group,
.domain_get_attr = arm_smmu_domain_get_attr,
.domain_set_attr = arm_smmu_domain_set_attr,
- .of_xlate = arm_smmu_of_xlate,
+ .fw_xlate = arm_smmu_fw_xlate,
.pgsize_bitmap = -1UL, /* Restricted during device attach */
};
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 5ecc86c..84ff5bb 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -1250,13 +1250,16 @@ static void exynos_iommu_remove_device(struct device *dev)
iommu_group_remove_device(dev);
}
-static int exynos_iommu_of_xlate(struct device *dev,
- struct of_phandle_args *spec)
+static int exynos_iommu_fw_xlate(struct device *dev,
+ struct iommu_fwspec *args)
{
struct exynos_iommu_owner *owner = dev->archdata.iommu;
- struct platform_device *sysmmu = of_find_device_by_node(spec->np);
+ struct platform_device *sysmmu = NULL;
struct sysmmu_drvdata *data;
+ if (is_of_node(args->fwnode))
+ sysmmu = of_find_device_by_node(to_of_node(args->fwnode));
+
if (!sysmmu)
return -ENODEV;
@@ -1290,7 +1293,7 @@ static struct iommu_ops exynos_iommu_ops = {
.add_device = exynos_iommu_add_device,
.remove_device = exynos_iommu_remove_device,
.pgsize_bitmap = SECT_SIZE | LPAGE_SIZE | SPAGE_SIZE,
- .of_xlate = exynos_iommu_of_xlate,
+ .fw_xlate = exynos_iommu_fw_xlate,
};
static bool init_done;
diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 929a66a..e08dc0a 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -436,20 +436,23 @@ static struct iommu_group *mtk_iommu_device_group(struct device *dev)
return data->m4u_group;
}
-static int mtk_iommu_of_xlate(struct device *dev, struct of_phandle_args *args)
+static int mtk_iommu_fw_xlate(struct device *dev, struct iommu_fwspec *args)
{
struct mtk_iommu_client_priv *head, *priv, *next;
struct platform_device *m4updev;
- if (args->args_count != 1) {
+ if (!is_of_node(args->fwnode))
+ return -ENODEV;
+
+ if (args->param_count != 1) {
dev_err(dev, "invalid #iommu-cells(%d) property for IOMMU\n",
- args->args_count);
+ args->param_count);
return -EINVAL;
}
if (!dev->archdata.iommu) {
/* Get the m4u device */
- m4updev = of_find_device_by_node(args->np);
+ m4updev = of_find_device_by_node(to_of_node(args->fwnode));
of_node_put(args->np);
if (WARN_ON(!m4updev))
return -EINVAL;
@@ -469,7 +472,7 @@ static int mtk_iommu_of_xlate(struct device *dev, struct of_phandle_args *args)
if (!priv)
goto err_free_mem;
- priv->mtk_m4u_id = args->args[0];
+ priv->mtk_m4u_id = args->param[0];
list_add_tail(&priv->client, &head->client);
return 0;
diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
index 910826c..331dd78 100644
--- a/drivers/iommu/of_iommu.c
+++ b/drivers/iommu/of_iommu.c
@@ -135,6 +135,18 @@ struct iommu_ops *of_iommu_get_ops(struct device_node *np)
return ops;
}
+static void of_phandle_args_to_fwspec(struct of_phandle_args *iommu_data,
+ struct iommu_fwspec *fwspec)
+{
+ int i;
+
+ fwspec->fwnode = iommu_data->np ? &iommu_data->np->fwnode : NULL;
+ fwspec->param_count = iommu_data->args_count;
+
+ for (i = 0; i < iommu_data->args_count; i++)
+ fwspec->param[i] = iommu_data->args[i];
+}
+
static int __get_pci_rid(struct pci_dev *pdev, u16 alias, void *data)
{
struct of_phandle_args *iommu_spec = data;
@@ -148,6 +160,7 @@ struct iommu_ops *of_iommu_configure(struct device *dev,
struct device_node *master_np)
{
struct of_phandle_args iommu_spec;
+ struct iommu_fwspec fwspec;
struct device_node *np = NULL;
struct iommu_ops *ops = NULL;
int idx = 0;
@@ -170,8 +183,9 @@ struct iommu_ops *of_iommu_configure(struct device *dev,
iommu_spec.np = np;
iommu_spec.args_count = 1;
+ of_phandle_args_to_fwspec(&iommu_spec, &fwspec);
ops = of_iommu_get_ops(np);
- if (!ops || !ops->of_xlate || ops->of_xlate(dev, &iommu_spec))
+ if (!ops || !ops->fw_xlate || ops->fw_xlate(dev, &fwspec))
goto err_put_node;
of_node_put(np);
@@ -189,7 +203,9 @@ struct iommu_ops *of_iommu_configure(struct device *dev,
np = iommu_spec.np;
ops = of_iommu_get_ops(np);
- if (!ops || !ops->of_xlate || ops->of_xlate(dev, &iommu_spec))
+ of_phandle_args_to_fwspec(&iommu_spec, &fwspec);
+
+ if (!ops || !ops->fw_xlate || ops->fw_xlate(dev, &fwspec))
goto err_put_node;
of_node_put(np);
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 0bba25e..5184d81 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -85,6 +85,24 @@ struct iommu_domain {
void *iova_cookie;
};
+#define IOMMU_MAP_SPEC_PARAMS 16
+
+/**
+ * struct iommu_fwspec - generic IOMMU specifier structure
+ *
+ * @fwnode: Pointer to a firmware-specific descriptor
+ * @param_count: Number of device-specific parameters
+ * @param: Device-specific parameters
+ *
+ * This structure, directly modeled after of_phandle_args, is used to
+ * pass a device-specific description of an IOMMU mapping.
+ */
+struct iommu_fwspec {
+ struct fwnode_handle *fwnode;
+ int param_count;
+ u32 param[IOMMU_MAP_SPEC_PARAMS];
+};
+
enum iommu_cap {
IOMMU_CAP_CACHE_COHERENCY, /* IOMMU can enforce cache coherent DMA
transactions */
@@ -155,7 +173,7 @@ struct iommu_dm_region {
* @domain_window_disable: Disable a particular window for a domain
* @domain_set_windows: Set the number of windows for a domain
* @domain_get_windows: Return the number of windows for a domain
- * @of_xlate: add OF master IDs to iommu grouping
+ * @fw_xlate: add FW master IDs to iommu grouping
* @pgsize_bitmap: bitmap of supported page sizes
* @priv: per-instance data private to the iommu driver
*/
@@ -196,9 +214,7 @@ struct iommu_ops {
/* Get the number of windows per domain */
u32 (*domain_get_windows)(struct iommu_domain *domain);
-#ifdef CONFIG_OF_IOMMU
- int (*of_xlate)(struct device *dev, struct of_phandle_args *args);
-#endif
+ int (*fw_xlate)(struct device *dev, struct iommu_fwspec *args);
unsigned long pgsize_bitmap;
void *priv;
--
2.6.4
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