On Thu, Jan 19, 2017 at 08:35:49PM +0530, Sricharan R wrote: > 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@xxxxxxxxxxxxxx> > --- > * 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. Rename the patch subject then, it is misleading. Thanks, Lorenzo > 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 > */ > -- > QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation > -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html