From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Sricharan" Subject: RE: [PATCH V3 4/8] drivers: platform: Configure dma operations at probe time Date: Wed, 26 Oct 2016 20:34:59 +0530 Message-ID: <003d01d22f9a$56477b80$02d67280$@codeaurora.org> References: <1475600632-21289-1-git-send-email-sricharan@codeaurora.org> <1475600632-21289-5-git-send-email-sricharan@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:41532 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932368AbcJZPFN (ORCPT ); Wed, 26 Oct 2016 11:05:13 -0400 In-Reply-To: Content-Language: en-us Sender: linux-arm-msm-owner@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org To: 'Robin Murphy' , will.deacon@arm.com, joro@8bytes.org, iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, laurent.pinchart@ideasonboard.com, m.szyprowski@samsung.com, tfiga@chromium.org, srinivas.kandagatla@linaro.org, 'Lorenzo Pieralisi' Hi Robin, >On 04/10/16 18:03, 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 >> --- >> drivers/base/dd.c | 10 ++++++++++ >> drivers/base/dma-mapping.c | 11 +++++++++++ >> drivers/of/platform.c | 4 ---- >> drivers/pci/probe.c | 5 +---- >> include/linux/dma-mapping.h | 3 +++ >> 5 files changed, 25 insertions(+), 8 deletions(-) >> >> diff --git a/drivers/base/dd.c b/drivers/base/dd.c >> index 16688f5..cfebd48 100644 >> --- a/drivers/base/dd.c >> +++ b/drivers/base/dd.c >> @@ -19,6 +19,7 @@ >> >> #include >> #include >> +#include >> #include >> #include >> #include >> @@ -353,6 +354,10 @@ 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)); >> @@ -395,6 +400,8 @@ 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); >> @@ -780,6 +787,9 @@ static void __device_release_driver(struct device *dev) >> dev->bus->remove(dev); >> else if (drv->remove) >> drv->remove(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 d799662..54e87f5 100644 >> --- a/drivers/base/dma-mapping.c >> +++ b/drivers/base/dma-mapping.c >> @@ -10,6 +10,7 @@ >> #include >> #include >> #include >> +#include >> #include >> #include >> >> @@ -166,6 +167,16 @@ void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr, >> } >> EXPORT_SYMBOL(dmam_free_noncoherent); >> >> +int dma_configure(struct device *dev) >> +{ >> + return of_dma_configure(dev, dev->of_node); >> +} >> + >> +void dma_deconfigure(struct device *dev) >> +{ >> + of_dma_deconfigure(dev); >> +} >> + >> #ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT >> >> static void dmam_coherent_decl_release(struct device *dev, void *res) >> diff --git a/drivers/of/platform.c b/drivers/of/platform.c >> index 9cb7090..adbd77c 100644 >> --- a/drivers/of/platform.c >> +++ b/drivers/of/platform.c >> @@ -181,11 +181,9 @@ 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; >> } >> @@ -242,7 +240,6 @@ 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); >> @@ -536,7 +533,6 @@ 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 93f280d..85c9553 100644 >> --- a/drivers/pci/probe.c >> +++ b/drivers/pci/probe.c >> @@ -1724,10 +1724,7 @@ 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); > >It seems a bit awkward leaving pci_dma_configure here, doing DMA >configuration at device add, after we've allegedly moved DMA >configuration to driver probe. Lorenzo, do you foresee any issues if >this probe-time of_dma_configure() path were to also multiplex >acpi_dma_configure() in future, such that everything would be back in >the same place eventually? > >Conversely, is there actually any issue with leaving pci_dma_configure() >unchanged, and simply moving the call from pci_device_add() into >dma_configure()? Ya i removed only the CONFIG_OF part out of this, and was hoping that the acpi configure can also be called from the dma_configure during probe later. I did not have an ACPI based platform though. As you said, if that looks right to the ACPI world, it can be moved out from here. I can try mergin series (after fixing the vfio errors part) with the ACPI IO port and see how it behaves. Regards, Sricharan From mboxrd@z Thu Jan 1 00:00:00 1970 From: sricharan@codeaurora.org (Sricharan) Date: Wed, 26 Oct 2016 20:34:59 +0530 Subject: [PATCH V3 4/8] drivers: platform: Configure dma operations at probe time In-Reply-To: References: <1475600632-21289-1-git-send-email-sricharan@codeaurora.org> <1475600632-21289-5-git-send-email-sricharan@codeaurora.org> Message-ID: <003d01d22f9a$56477b80$02d67280$@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Robin, >On 04/10/16 18:03, 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 >> --- >> drivers/base/dd.c | 10 ++++++++++ >> drivers/base/dma-mapping.c | 11 +++++++++++ >> drivers/of/platform.c | 4 ---- >> drivers/pci/probe.c | 5 +---- >> include/linux/dma-mapping.h | 3 +++ >> 5 files changed, 25 insertions(+), 8 deletions(-) >> >> diff --git a/drivers/base/dd.c b/drivers/base/dd.c >> index 16688f5..cfebd48 100644 >> --- a/drivers/base/dd.c >> +++ b/drivers/base/dd.c >> @@ -19,6 +19,7 @@ >> >> #include >> #include >> +#include >> #include >> #include >> #include >> @@ -353,6 +354,10 @@ 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)); >> @@ -395,6 +400,8 @@ 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); >> @@ -780,6 +787,9 @@ static void __device_release_driver(struct device *dev) >> dev->bus->remove(dev); >> else if (drv->remove) >> drv->remove(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 d799662..54e87f5 100644 >> --- a/drivers/base/dma-mapping.c >> +++ b/drivers/base/dma-mapping.c >> @@ -10,6 +10,7 @@ >> #include >> #include >> #include >> +#include >> #include >> #include >> >> @@ -166,6 +167,16 @@ void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr, >> } >> EXPORT_SYMBOL(dmam_free_noncoherent); >> >> +int dma_configure(struct device *dev) >> +{ >> + return of_dma_configure(dev, dev->of_node); >> +} >> + >> +void dma_deconfigure(struct device *dev) >> +{ >> + of_dma_deconfigure(dev); >> +} >> + >> #ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT >> >> static void dmam_coherent_decl_release(struct device *dev, void *res) >> diff --git a/drivers/of/platform.c b/drivers/of/platform.c >> index 9cb7090..adbd77c 100644 >> --- a/drivers/of/platform.c >> +++ b/drivers/of/platform.c >> @@ -181,11 +181,9 @@ 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; >> } >> @@ -242,7 +240,6 @@ 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); >> @@ -536,7 +533,6 @@ 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 93f280d..85c9553 100644 >> --- a/drivers/pci/probe.c >> +++ b/drivers/pci/probe.c >> @@ -1724,10 +1724,7 @@ 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); > >It seems a bit awkward leaving pci_dma_configure here, doing DMA >configuration at device add, after we've allegedly moved DMA >configuration to driver probe. Lorenzo, do you foresee any issues if >this probe-time of_dma_configure() path were to also multiplex >acpi_dma_configure() in future, such that everything would be back in >the same place eventually? > >Conversely, is there actually any issue with leaving pci_dma_configure() >unchanged, and simply moving the call from pci_device_add() into >dma_configure()? Ya i removed only the CONFIG_OF part out of this, and was hoping that the acpi configure can also be called from the dma_configure during probe later. I did not have an ACPI based platform though. As you said, if that looks right to the ACPI world, it can be moved out from here. I can try mergin series (after fixing the vfio errors part) with the ACPI IO port and see how it behaves. Regards, Sricharan