[PATCH V5 05/12] drivers: platform: Configure dma operations at probe time
Sricharan R
sricharan at codeaurora.org
Thu Jan 19 07:05:49 PST 2017
Configuring DMA ops at probe time will allow deferring device probe when
the IOMMU isn't available yet. The dma_configure for the device is
now called from the generic device_attach callback just before the
bus/driver probe is called. This way, configuring the DMA ops for the
device would be called at the same place for all bus_types, hence the
deferred probing mechanism should work for all buses as well.
pci_bus_add_devices (platform/amba)(_device_create/driver_register)
| |
pci_bus_add_device (device_add/driver_register)
| |
device_attach device_initial_probe
| |
__device_attach_driver __device_attach_driver
|
driver_probe_device
|
really_probe
|
dma_configure
Similarly on the device/driver_unregister path __device_release_driver is
called which inturn calls dma_deconfigure.
Signed-off-by: Sricharan R <sricharan at codeaurora.org>
---
* Removed the dma configuration for the pci devices in case of DT
from pci_dma_configure which was hanging outside separately and
doing it in dma_configure function itself.
drivers/base/dd.c | 9 +++++++++
drivers/base/dma-mapping.c | 32 ++++++++++++++++++++++++++++++++
drivers/of/platform.c | 5 +----
drivers/pci/probe.c | 5 +----
include/linux/dma-mapping.h | 3 +++
5 files changed, 46 insertions(+), 8 deletions(-)
diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index a1fbf55..4882f06 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -19,6 +19,7 @@
#include <linux/device.h>
#include <linux/delay.h>
+#include <linux/dma-mapping.h>
#include <linux/module.h>
#include <linux/kthread.h>
#include <linux/wait.h>
@@ -356,6 +357,10 @@ static int really_probe(struct device *dev, struct device_driver *drv)
if (ret)
goto pinctrl_bind_failed;
+ ret = dma_configure(dev);
+ if (ret)
+ goto dma_failed;
+
if (driver_sysfs_add(dev)) {
printk(KERN_ERR "%s: driver_sysfs_add(%s) failed\n",
__func__, dev_name(dev));
@@ -417,6 +422,8 @@ static int really_probe(struct device *dev, struct device_driver *drv)
goto done;
probe_failed:
+ dma_deconfigure(dev);
+dma_failed:
if (dev->bus)
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
BUS_NOTIFY_DRIVER_NOT_BOUND, dev);
@@ -826,6 +833,8 @@ static void __device_release_driver(struct device *dev, struct device *parent)
drv->remove(dev);
device_links_driver_cleanup(dev);
+ dma_deconfigure(dev);
+
devres_release_all(dev);
dev->driver = NULL;
dev_set_drvdata(dev, NULL);
diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c
index efd71cf..dfe6fd7 100644
--- a/drivers/base/dma-mapping.c
+++ b/drivers/base/dma-mapping.c
@@ -10,6 +10,7 @@
#include <linux/dma-mapping.h>
#include <linux/export.h>
#include <linux/gfp.h>
+#include <linux/of_device.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
@@ -341,3 +342,34 @@ void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
vunmap(cpu_addr);
}
#endif
+
+/*
+ * Common configuration to enable DMA API use for a device
+ */
+#include <linux/pci.h>
+
+int dma_configure(struct device *dev)
+{
+ struct device *_dev = dev;
+ int is_pci = dev_is_pci(dev);
+
+ if (is_pci) {
+ _dev = pci_get_host_bridge_device(to_pci_dev(dev));
+ if (IS_ENABLED(CONFIG_OF) && _dev->parent &&
+ _dev->parent->of_node)
+ _dev = _dev->parent;
+ }
+
+ if (_dev->of_node)
+ of_dma_configure(dev, _dev->of_node);
+
+ if (is_pci)
+ pci_put_host_bridge_device(_dev);
+
+ return 0;
+}
+
+void dma_deconfigure(struct device *dev)
+{
+ of_dma_deconfigure(dev);
+}
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 57418f7..cf35030 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -22,6 +22,7 @@
#include <linux/slab.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
+#include <linux/of_iommu.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
@@ -186,11 +187,9 @@ static struct platform_device *of_platform_device_create_pdata(
dev->dev.bus = &platform_bus_type;
dev->dev.platform_data = platform_data;
- of_dma_configure(&dev->dev, dev->dev.of_node);
of_msi_configure(&dev->dev, dev->dev.of_node);
if (of_device_add(dev) != 0) {
- of_dma_deconfigure(&dev->dev);
platform_device_put(dev);
goto err_clear_flag;
}
@@ -248,7 +247,6 @@ static struct amba_device *of_amba_device_create(struct device_node *node,
dev_set_name(&dev->dev, "%s", bus_id);
else
of_device_make_bus_id(&dev->dev);
- of_dma_configure(&dev->dev, dev->dev.of_node);
/* Allow the HW Peripheral ID to be overridden */
prop = of_get_property(node, "arm,primecell-periphid", NULL);
@@ -542,7 +540,6 @@ static int of_platform_device_destroy(struct device *dev, void *data)
amba_device_unregister(to_amba_device(dev));
#endif
- of_dma_deconfigure(dev);
of_node_clear_flag(dev->of_node, OF_POPULATED);
of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
return 0;
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index e164b5c..634d34e 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1873,10 +1873,7 @@ static void pci_dma_configure(struct pci_dev *dev)
{
struct device *bridge = pci_get_host_bridge_device(dev);
- if (IS_ENABLED(CONFIG_OF) &&
- bridge->parent && bridge->parent->of_node) {
- of_dma_configure(&dev->dev, bridge->parent->of_node);
- } else if (has_acpi_companion(bridge)) {
+ if (has_acpi_companion(bridge)) {
struct acpi_device *adev = to_acpi_device_node(bridge->fwnode);
enum dev_dma_attr attr = acpi_get_dma_attr(adev);
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index abf685ed..b56320a 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -718,6 +718,9 @@ void *dma_mark_declared_memory_occupied(struct device *dev,
}
#endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */
+int dma_configure(struct device *dev);
+void dma_deconfigure(struct device *dev);
+
/*
* Managed DMA API
*/
--
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