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. 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