On 04/04/17 11:18, 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. > > This patch changes the dma ops configuration to probe time for > both OF and ACPI based platform/amba/pci bus devices.
Reviewed-by: Robin Murphy <[email protected]> It's possible we could subsume {of,acpi}_dma_deconfigure() into dma_deconfigure() entirely in future if it becomes clear that neither of them will ever need to do anything firmware-specific, but I think for now it's probably safer to keep the current symmetry - calling arch_teardown_dma_ops() twice is benign (and even if it weren't, I'd say it really should be!) Robin. > Tested-by: Marek Szyprowski <[email protected]> > Tested-by: Hanjun Guo <[email protected]> > Acked-by: Bjorn Helgaas <[email protected]> (drivers/pci part) > Acked-by: Rafael J. Wysocki <[email protected]> > Signed-off-by: Sricharan R <[email protected]> > --- > > [V10] Added dummy dma_(de)configure functions in case > of !CONFIG_HAS_DMA to avoid build breaks. > > drivers/acpi/glue.c | 5 ----- > drivers/base/dd.c | 9 +++++++++ > drivers/base/dma-mapping.c | 40 ++++++++++++++++++++++++++++++++++++++++ > drivers/of/platform.c | 5 +---- > drivers/pci/probe.c | 28 ---------------------------- > include/linux/dma-mapping.h | 12 ++++++++++++ > 6 files changed, 62 insertions(+), 37 deletions(-) > > diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c > index fb19e1c..c05f241 100644 > --- a/drivers/acpi/glue.c > +++ b/drivers/acpi/glue.c > @@ -176,7 +176,6 @@ int acpi_bind_one(struct device *dev, struct acpi_device > *acpi_dev) > struct list_head *physnode_list; > unsigned int node_id; > int retval = -EINVAL; > - enum dev_dma_attr attr; > > if (has_acpi_companion(dev)) { > if (acpi_dev) { > @@ -233,10 +232,6 @@ int acpi_bind_one(struct device *dev, struct acpi_device > *acpi_dev) > if (!has_acpi_companion(dev)) > ACPI_COMPANION_SET(dev, acpi_dev); > > - attr = acpi_get_dma_attr(acpi_dev); > - if (attr != DEV_DMA_NOT_SUPPORTED) > - acpi_dma_configure(dev, attr); > - > acpi_physnode_link_name(physical_node_name, node_id); > retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj, > physical_node_name); > 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..449b948 100644 > --- a/drivers/base/dma-mapping.c > +++ b/drivers/base/dma-mapping.c > @@ -7,9 +7,11 @@ > * This file is released under the GPLv2. > */ > > +#include <linux/acpi.h> > #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 +343,41 @@ 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 *bridge = NULL, *dma_dev = dev; > + enum dev_dma_attr attr; > + > + if (dev_is_pci(dev)) { > + bridge = pci_get_host_bridge_device(to_pci_dev(dev)); > + dma_dev = bridge; > + if (IS_ENABLED(CONFIG_OF) && dma_dev->parent && > + dma_dev->parent->of_node) > + dma_dev = dma_dev->parent; > + } > + > + if (dma_dev->of_node) { > + of_dma_configure(dev, dma_dev->of_node); > + } else if (has_acpi_companion(dma_dev)) { > + attr = acpi_get_dma_attr(to_acpi_device_node(dma_dev->fwnode)); > + if (attr != DEV_DMA_NOT_SUPPORTED) > + acpi_dma_configure(dev, attr); > + } > + > + if (bridge) > + pci_put_host_bridge_device(bridge); > + > + return 0; > +} > + > +void dma_deconfigure(struct device *dev) > +{ > + of_dma_deconfigure(dev); > + acpi_dma_deconfigure(dev); > +} > diff --git a/drivers/of/platform.c b/drivers/of/platform.c > index 5344db5..2aa4ebb 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 dfc9a27..5a8dd43 100644 > --- a/drivers/pci/probe.c > +++ b/drivers/pci/probe.c > @@ -1893,33 +1893,6 @@ static void pci_set_msi_domain(struct pci_dev *dev) > dev_set_msi_domain(&dev->dev, d); > } > > -/** > - * pci_dma_configure - Setup DMA configuration > - * @dev: ptr to pci_dev struct of the PCI device > - * > - * Function to update PCI devices's DMA configuration using the same > - * info from the OF node or ACPI node of host bridge's parent (if any). > - */ > -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)) { > - struct acpi_device *adev = to_acpi_device_node(bridge->fwnode); > - enum dev_dma_attr attr = acpi_get_dma_attr(adev); > - > - if (attr == DEV_DMA_NOT_SUPPORTED) > - dev_warn(&dev->dev, "DMA not supported.\n"); > - else > - acpi_dma_configure(&dev->dev, attr); > - } > - > - pci_put_host_bridge_device(bridge); > -} > - > void pci_device_add(struct pci_dev *dev, struct pci_bus *bus) > { > int ret; > @@ -1933,7 +1906,6 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus > *bus) > dev->dev.dma_mask = &dev->dma_mask; > dev->dev.dma_parms = &dev->dma_parms; > dev->dev.coherent_dma_mask = 0xffffffffull; > - pci_dma_configure(dev); > > pci_set_dma_max_seg_size(dev, 65536); > pci_set_dma_seg_boundary(dev, 0xffffffff); > diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h > index 0977317..4f3eece 100644 > --- a/include/linux/dma-mapping.h > +++ b/include/linux/dma-mapping.h > @@ -728,6 +728,18 @@ void *dma_mark_declared_memory_occupied(struct device > *dev, > } > #endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */ > > +#ifdef CONFIG_HAS_DMA > +int dma_configure(struct device *dev); > +void dma_deconfigure(struct device *dev); > +#else > +static inline int dma_configure(struct device *dev) > +{ > + return 0; > +} > + > +static inline void dma_deconfigure(struct device *dev) {} > +#endif > + > /* > * Managed DMA API > */ >
