From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Tue, 10 Apr 2018 14:20:41 -0500 From: Bjorn Helgaas To: Nipun Gupta Cc: robin.murphy@arm.com, hch@lst.de, linux@armlinux.org.uk, gregkh@linuxfoundation.org, m.szyprowski@samsung.com, bhelgaas@google.com, zajec5@gmail.com, andy.gross@linaro.org, david.brown@linaro.org, dan.j.williams@intel.com, vinod.koul@intel.com, thierry.reding@gmail.com, robh+dt@kernel.org, frowand.list@gmail.com, jarkko.sakkinen@linux.intel.com, rafael.j.wysocki@intel.com, dmitry.torokhov@gmail.com, johan@kernel.org, msuchanek@suse.de, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, linux-wireless@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org, dmaengine@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-tegra@vger.kernel.org, devicetree@vger.kernel.org, linux-pci@vger.kernel.org, bharat.bhushan@nxp.com, leoyang.li@nxp.com Subject: Re: [PATCH v3 1/2] dma-mapping: move dma configuration to bus infrastructure Message-ID: <20180410192041.GA54986@bhelgaas-glaptop.roam.corp.google.com> References: <1520868292-2479-1-git-send-email-nipun.gupta@nxp.com> <1522396485-10248-1-git-send-email-nipun.gupta@nxp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1522396485-10248-1-git-send-email-nipun.gupta@nxp.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: On Fri, Mar 30, 2018 at 01:24:44PM +0530, Nipun Gupta wrote: > It is 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. s/dma/DMA/ consistently above. > Suggested-by: Christoph Hellwig > Signed-off-by: Nipun Gupta > Reviewed-by: Greg Kroah-Hartman Acked-by: Bjorn Helgaas # PCI parts I assume you'll merge this via some non-PCI tree. Let me know if you need anything else from me. > --- > - 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 > > Changes in v3 > - Move dma_common_configure() within platform_dma_configure() and > reuse platofrm_dma_configure() for AMBA bus too > - Declare 'attr' in pci_dma_configure() inside the else statement > where it is used. > > drivers/amba/bus.c | 4 ++++ > drivers/base/dma-mapping.c | 31 ++++--------------------------- > drivers/base/platform.c | 17 +++++++++++++++++ > drivers/gpu/host1x/bus.c | 8 ++++++++ > drivers/pci/pci-driver.c | 32 ++++++++++++++++++++++++++++++++ > include/linux/device.h | 4 ++++ > include/linux/platform_device.h | 2 ++ > 7 files changed, 71 insertions(+), 27 deletions(-) > > diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c > index 594c228..867dc2b 100644 > --- a/drivers/amba/bus.c > +++ b/drivers/amba/bus.c > @@ -20,6 +20,7 @@ > #include > #include > #include > +#include > > #include > > @@ -188,12 +189,15 @@ static int amba_pm_runtime_resume(struct device *dev) > /* > * Primecells are part of the Advanced Microcontroller Bus Architecture, > * so we call the bus "amba". > + * DMA configuration for platform and AMBA bus is same. So here we reuse > + * platform's DMA config routine. > */ > struct bus_type amba_bustype = { > .name = "amba", > .dev_groups = amba_dev_groups, > .match = amba_match, > .uevent = amba_uevent, > + .dma_configure = platform_dma_configure, > .pm = &amba_pm, > .force_dma = true, > }; > diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c > index 3b11835..fdc1502 100644 > --- a/drivers/base/dma-mapping.c > +++ b/drivers/base/dma-mapping.c > @@ -331,36 +331,13 @@ 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 > + * enables DMA API use for a device > */ > -#include > - > int dma_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 (attr != DEV_DMA_NOT_SUPPORTED) > - ret = acpi_dma_configure(dev, attr); > - } > - > - if (bridge) > - pci_put_host_bridge_device(bridge); > - > - return ret; > + if (dev->bus->dma_configure) > + return dev->bus->dma_configure(dev); > + return 0; > } > > void dma_deconfigure(struct device *dev) > diff --git a/drivers/base/platform.c b/drivers/base/platform.c > index f1bf7b3..72fdbf6 100644 > --- a/drivers/base/platform.c > +++ b/drivers/base/platform.c > @@ -1130,6 +1130,22 @@ int platform_pm_restore(struct device *dev) > > #endif /* CONFIG_HIBERNATE_CALLBACKS */ > > +int platform_dma_configure(struct device *dev) > +{ > + enum dev_dma_attr attr; > + int ret = 0; > + > + 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); > + } > + > + return ret; > +} > + > static const struct dev_pm_ops platform_dev_pm_ops = { > .runtime_suspend = pm_generic_runtime_suspend, > .runtime_resume = pm_generic_runtime_resume, > @@ -1141,6 +1157,7 @@ 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..a9ec99d 100644 > --- a/drivers/gpu/host1x/bus.c > +++ b/drivers/gpu/host1x/bus.c > @@ -314,6 +314,13 @@ 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 +333,7 @@ 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..78e507f 100644 > --- a/drivers/pci/pci-driver.c > +++ b/drivers/pci/pci-driver.c > @@ -18,6 +18,8 @@ > #include > #include > #include > +#include > +#include > #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; > + 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)) { > + 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) > + 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/platform_device.h b/include/linux/platform_device.h > index 49f634d..3097c94 100644 > --- a/include/linux/platform_device.h > +++ b/include/linux/platform_device.h > @@ -356,6 +356,8 @@ static inline char *early_platform_driver_setup_func(void) \ > #define platform_pm_restore NULL > #endif > > +extern int platform_dma_configure(struct device *dev); > + > #ifdef CONFIG_PM_SLEEP > #define USE_PLATFORM_PM_SLEEP_OPS \ > .suspend = platform_pm_suspend, \ > -- > 1.9.1 >