[PATCH 10/11] of: device: introduce of_dma_configure_parent()

Nicolas Saenz Julienne
2019-09-24T18:13:16Z

Devices not represented in DT, placed behind a bus that autodetects
them, pass of_dma_configure() their bus' DT node. This misses that bus'
'dma-ranges' property as the function's implementation expects the DT
node to be one of a device.

Create of_dma_configure_parent() which takes the given DT node as the
device's underlying bus and parses it accordingly.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
---

drivers/bus/fsl-mc/fsl-mc-bus.c | 2 +-
drivers/gpu/host1x/bus.c | 2 +-
drivers/of/device.c | 30 ++++++++++++++++++++++++++++--
drivers/pci/pci-driver.c | 3 ++-
include/linux/of_device.h | 13 ++++++++++---
5 files changed, 42 insertions(+), 8 deletions(-)

diff --git a/drivers/bus/fsl-mc/fsl-mc-bus.c b/drivers/bus/fsl-mc/fsl-mc-bus.c
index 5c9bf2e06552..217e64119497 100644
--- a/drivers/bus/fsl-mc/fsl-mc-bus.c
+++ b/drivers/bus/fsl-mc/fsl-mc-bus.c
@@ -134,7 +134,7 @@ static int fsl_mc_dma_configure(struct device *dev)
while (dev_is_fsl_mc(dma_dev))
dma_dev = dma_dev->parent;

- return of_dma_configure(dev, dma_dev->of_node, 0);
+ return of_dma_configure_parent(dev, dma_dev->of_node, false);
}

static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
diff --git a/drivers/gpu/host1x/bus.c b/drivers/gpu/host1x/bus.c
index 742aa9ff21b8..2fdc04383a60 100644
--- a/drivers/gpu/host1x/bus.c
+++ b/drivers/gpu/host1x/bus.c
@@ -442,7 +442,7 @@ static int host1x_device_add(struct host1x *host1x,
device->dev.bus = &host1x_bus_type;
device->dev.parent = host1x->dev;

- of_dma_configure(&device->dev, host1x->dev->of_node, true);
+ of_dma_configure_parent(&device->dev, host1x->dev->of_node, true);

device->dev.dma_parms = &device->dma_parms;
dma_set_max_seg_size(&device->dev, SZ_4M);
diff --git a/drivers/of/device.c b/drivers/of/device.c
index 018c52688546..1d0b1127d05e 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -83,6 +83,31 @@ int of_device_add(struct platform_device *ofdev)
* accordingly.
*/
int of_dma_configure(struct device *dev, struct device_node *np, bool force_dma)
+{
+ struct device_node *dma_parent;
+ int ret;
+
+ dma_parent = __of_get_dma_parent(np);
+ ret = of_dma_configure_parent(dev, dma_parent, force_dma);
+ of_node_put(dma_parent);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(of_dma_configure);
+
+/**
+ * of_dma_configure_parent - Setup DMA configuration based on a parent bus'
+ * DT node
+ * @dev: Device to apply DMA configuration
+ * @parent: Parent bus device node
+ * @force_dma: Whether device is to be set up by of_dma_configure() even if
+ * DMA capability is not explicitly described by firmware.
+ *
+ * Try to get devices's DMA configuration from parent bus' DT and update it
+ * accordingly.
+ */
+int of_dma_configure_parent(struct device *dev, struct device_node *parent,
+ bool force_dma)
{
u64 dma_addr, paddr, size = 0;
int ret;
@@ -91,8 +116,9 @@ int of_dma_configure(struct device *dev, struct device_node *np, bool force_dma)
const struct iommu_ops *iommu;
u64 mask;

- ret = of_dma_get_range(__of_get_dma_parent(np), &dma_addr,
- &paddr, &size);
+ dev_dbg(dev, "starting at %pOF\n", parent);
+
+ ret = of_dma_get_range(parent, &dma_addr, &paddr, &size);
if (ret < 0) {
/*
* For legacy reasons, we have to assume some devices need
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index a8124e47bf6e..25073d68a0f6 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -1628,7 +1628,8 @@ static int pci_dma_configure(struct device *dev)

if (IS_ENABLED(CONFIG_OF) && bridge->parent &&
bridge->parent->of_node) {
- ret = of_dma_configure(dev, bridge->parent->of_node, true);
+ ret = of_dma_configure_parent(dev, bridge->parent->of_node,
+ true);
} else if (has_acpi_companion(bridge)) {
struct acpi_device *adev = to_acpi_device_node(bridge->fwnode);

diff --git a/include/linux/of_device.h b/include/linux/of_device.h
index 8d31e39dd564..8f319b8c9deb 100644
--- a/include/linux/of_device.h
+++ b/include/linux/of_device.h
@@ -55,9 +55,9 @@ static inline struct device_node *of_cpu_device_node_get(int cpu)
return of_node_get(cpu_dev->of_node);
}

-int of_dma_configure(struct device *dev,
- struct device_node *np,
- bool force_dma);
+int of_dma_configure(struct device *dev, struct devce_node *np, bool force_dma);
+int of_dma_configure_parent(struct device *dev, struct device_node *parent,
+ bool force_dma);
#else /* CONFIG_OF */

static inline int of_driver_match_device(struct device *dev,
@@ -112,6 +112,13 @@ static inline int of_dma_configure(struct device *dev,
{
return 0;
}
+
+static inline int of_dma_configure_parent(struct device *dev,
+ struct device_node *parent,
+ bool force_dma)
+{
+ return 0;
+}
#endif /* CONFIG_OF */

#endif /* _LINUX_OF_DEVICE_H */
--
2.23.0