On Wed, Mar 21, 2018 at 12:25:22PM +0530, Nipun Gupta wrote: > It's bus specific aspect to map a given device on the bus and > relevant firmware description of its DMA configuration. > So, this change introduces '/dma_configure/' as bus callback > giving flexibility to busses for implementing its own dma > configuration function. > > The change eases the addition of new busses w.r.t. adding the dma > configuration functionality. > > This patch also updates the PCI, Platform, ACPI and host1x bus to > use new introduced callbacks. > > Suggested-by: Christoph Hellwig <hch@xxxxxx> > Signed-off-by: Nipun Gupta <nipun.gupta@xxxxxxx> > --- > - The patches are based on the comments on: > https://patchwork.kernel.org/patch/10259087/ > > Changes in v2: > - Do not have dma_deconfigure callback > - Have '/dma_common_configure/' API to provide a common DMA > configuration which can be used by busses if it suits them. > - Platform and ACPI bus to use '/dma_common_configure/' in > '/dma_configure/' callback. > - Updated commit message > - Updated pci_dma_configure API with changes suggested by Robin > > drivers/amba/bus.c | 7 +++++++ > drivers/base/dma-mapping.c | 35 +++++++++++++++-------------------- > drivers/base/platform.c | 6 ++++++ > drivers/gpu/host1x/bus.c | 9 +++++++++ > drivers/pci/pci-driver.c | 32 ++++++++++++++++++++++++++++++++ > include/linux/device.h | 4 ++++ > include/linux/dma-mapping.h | 1 + > 7 files changed, 74 insertions(+), 20 deletions(-) > > diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c > index 594c228..2fa1e8b 100644 > --- a/drivers/amba/bus.c > +++ b/drivers/amba/bus.c > @@ -20,6 +20,7 @@ > #include <linux/sizes.h> > #include <linux/limits.h> > #include <linux/clk/clk-conf.h> > +#include <linux/dma-mapping.h> > > #include <asm/irq.h> > > @@ -171,6 +172,11 @@ static int amba_pm_runtime_resume(struct device *dev) > } > #endif /* CONFIG_PM */ > > +static int amba_dma_configure(struct device *dev) > +{ > + return dma_common_configure(dev); > +} > + > static const struct dev_pm_ops amba_pm = { > .suspend = pm_generic_suspend, > .resume = pm_generic_resume, > @@ -194,6 +200,7 @@ struct bus_type amba_bustype = { > .dev_groups = amba_dev_groups, > .match = amba_match, > .uevent = amba_uevent, > + .dma_configure = amba_dma_configure, > .pm = &amba_pm, > .force_dma = true, > }; > diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c > index 3b11835..48f9af0 100644 > --- a/drivers/base/dma-mapping.c > +++ b/drivers/base/dma-mapping.c > @@ -331,38 +331,33 @@ void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags) > #endif > > /* > - * Common configuration to enable DMA API use for a device > + * Common configuration to enable DMA API use for a device. > + * A bus can use this function in its 'dma_configure' callback, if > + * suitable for the bus. > */ > -#include <linux/pci.h> > - > -int dma_configure(struct device *dev) > +int dma_common_configure(struct device *dev) > { > - struct device *bridge = NULL, *dma_dev = dev; > enum dev_dma_attr attr; > int ret = 0; > > - 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) { > - ret = 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 (dev->of_node) { > + ret = of_dma_configure(dev, dev->of_node); > + } else if (has_acpi_companion(dev)) { > + attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode)); > if (attr != DEV_DMA_NOT_SUPPORTED) > ret = acpi_dma_configure(dev, attr); > } > > - if (bridge) > - pci_put_host_bridge_device(bridge); > - > return ret; > } > > +int dma_configure(struct device *dev) > +{ > + if (dev->bus->dma_configure) > + return dev->bus->dma_configure(dev); > + > + return 0; > +} > void dma_deconfigure(struct device *dev) Empty line after this new function? Sorry, couldn't help it :) > { > of_dma_deconfigure(dev); > diff --git a/drivers/base/platform.c b/drivers/base/platform.c > index f1bf7b3..d2d5891 100644 > --- a/drivers/base/platform.c > +++ b/drivers/base/platform.c > @@ -1130,6 +1130,11 @@ int platform_pm_restore(struct device *dev) > > #endif /* CONFIG_HIBERNATE_CALLBACKS */ > > +static int platform_dma_configure(struct device *dev) > +{ > + return dma_common_configure(dev); > +} > + > static const struct dev_pm_ops platform_dev_pm_ops = { > .runtime_suspend = pm_generic_runtime_suspend, > .runtime_resume = pm_generic_runtime_resume, > @@ -1141,6 +1146,7 @@ struct bus_type platform_bus_type = { > .dev_groups = platform_dev_groups, > .match = platform_match, > .uevent = platform_uevent, > + .dma_configure = platform_dma_configure, > .pm = &platform_dev_pm_ops, > .force_dma = true, > }; > diff --git a/drivers/gpu/host1x/bus.c b/drivers/gpu/host1x/bus.c > index 88a3558..fa9896d 100644 > --- a/drivers/gpu/host1x/bus.c > +++ b/drivers/gpu/host1x/bus.c > @@ -314,6 +314,14 @@ static int host1x_device_match(struct device *dev, struct device_driver *drv) > return strcmp(dev_name(dev), drv->name) == 0; > } > > +static int host1x_dma_configure(struct device *dev) > +{ > + if (dev->of_node) > + return of_dma_configure(dev, dev->of_node); > + > + return 0; > +} > + > static const struct dev_pm_ops host1x_device_pm_ops = { > .suspend = pm_generic_suspend, > .resume = pm_generic_resume, > @@ -326,6 +334,7 @@ static int host1x_device_match(struct device *dev, struct device_driver *drv) > struct bus_type host1x_bus_type = { > .name = "host1x", > .match = host1x_device_match, > + .dma_configure = host1x_dma_configure, > .pm = &host1x_device_pm_ops, > .force_dma = true, > }; > diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c > index 3bed6be..b473a4c 100644 > --- a/drivers/pci/pci-driver.c > +++ b/drivers/pci/pci-driver.c > @@ -18,6 +18,8 @@ > #include <linux/pm_runtime.h> > #include <linux/suspend.h> > #include <linux/kexec.h> > +#include <linux/of_device.h> > +#include <linux/acpi.h> > #include "pci.h" > > struct pci_dynid { > @@ -1522,6 +1524,35 @@ static int pci_bus_num_vf(struct device *dev) > return pci_num_vf(to_pci_dev(dev)); > } > > +/** > + * pci_dma_configure - Setup DMA configuration > + * @dev: ptr to dev structure > + * > + * 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 int pci_dma_configure(struct device *dev) > +{ > + struct device *bridge; > + enum dev_dma_attr attr; > + int ret = 0; > + > + bridge = pci_get_host_bridge_device(to_pci_dev(dev)); > + > + if (IS_ENABLED(CONFIG_OF) && bridge->parent && > + bridge->parent->of_node) { > + ret = of_dma_configure(dev, bridge->parent->of_node); > + } else if (has_acpi_companion(bridge)) { > + attr = acpi_get_dma_attr(to_acpi_device_node(bridge->fwnode)); > + if (attr != DEV_DMA_NOT_SUPPORTED) > + ret = acpi_dma_configure(dev, attr); > + } > + > + pci_put_host_bridge_device(bridge); > + > + return ret; > +} > + > struct bus_type pci_bus_type = { > .name = "pci", > .match = pci_bus_match, > @@ -1534,6 +1565,7 @@ struct bus_type pci_bus_type = { > .drv_groups = pci_drv_groups, > .pm = PCI_PM_OPS_PTR, > .num_vf = pci_bus_num_vf, > + .dma_configure = pci_dma_configure, > .force_dma = true, > }; > EXPORT_SYMBOL(pci_bus_type); > diff --git a/include/linux/device.h b/include/linux/device.h > index b093405..1832d90 100644 > --- a/include/linux/device.h > +++ b/include/linux/device.h > @@ -88,6 +88,8 @@ extern int __must_check bus_create_file(struct bus_type *, > * @resume: Called to bring a device on this bus out of sleep mode. > * @num_vf: Called to find out how many virtual functions a device on this > * bus supports. > + * @dma_configure: Called to setup DMA configuration on a device on > + this bus. > * @pm: Power management operations of this bus, callback the specific > * device driver's pm-ops. > * @iommu_ops: IOMMU specific operations for this bus, used to attach IOMMU > @@ -130,6 +132,8 @@ struct bus_type { > > int (*num_vf)(struct device *dev); > > + int (*dma_configure)(struct device *dev); > + > const struct dev_pm_ops *pm; > > const struct iommu_ops *iommu_ops; > diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h > index eb9eab4..c15986b 100644 > --- a/include/linux/dma-mapping.h > +++ b/include/linux/dma-mapping.h > @@ -761,6 +761,7 @@ void *dma_mark_declared_memory_occupied(struct device *dev, > } > #endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */ > > +int dma_common_configure(struct device *dev); > #ifdef CONFIG_HAS_DMA Blank line after the new function declaration? Other than those very minor things, nice job, this looks good: Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
