diff options
Diffstat (limited to 'freed-ora/tags/f27/4.15.9-300.fc27.gnu/bcm283x-dma-mapping-skip-USB-devices-when-configuring-DMA-during-probe.patch')
| -rw-r--r-- | freed-ora/tags/f27/4.15.9-300.fc27.gnu/bcm283x-dma-mapping-skip-USB-devices-when-configuring-DMA-during-probe.patch | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/freed-ora/tags/f27/4.15.9-300.fc27.gnu/bcm283x-dma-mapping-skip-USB-devices-when-configuring-DMA-during-probe.patch b/freed-ora/tags/f27/4.15.9-300.fc27.gnu/bcm283x-dma-mapping-skip-USB-devices-when-configuring-DMA-during-probe.patch new file mode 100644 index 000000000..c6f7f12de --- /dev/null +++ b/freed-ora/tags/f27/4.15.9-300.fc27.gnu/bcm283x-dma-mapping-skip-USB-devices-when-configuring-DMA-during-probe.patch @@ -0,0 +1,127 @@ +From patchwork Thu Aug 3 15:52:08 2017 +Content-Type: text/plain; charset="utf-8" +MIME-Version: 1.0 +Content-Transfer-Encoding: 7bit +Subject: [v3] dma-mapping: skip USB devices when configuring DMA during probe +From: Johan Hovold <johan@kernel.org> +X-Patchwork-Id: 9879371 +Message-Id: <20170803155208.22165-1-johan@kernel.org> +To: Christoph Hellwig <hch@lst.de>, + Marek Szyprowski <m.szyprowski@samsung.com>, + Greg Kroah-Hartman <gregkh@linuxfoundation.org> +Cc: =?UTF-8?q?Andreas=20F=C3=A4rber?= <afaerber@suse.de>, + linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, + Alan Stern <stern@rowland.harvard.edu>, Johan Hovold <johan@kernel.org>, + stable <stable@vger.kernel.org>, Robin Murphy <robin.murphy@arm.com>, + Sricharan R <sricharan@codeaurora.org>, + Stefan Wahren <stefan.wahren@i2se.com> +Date: Thu, 3 Aug 2017 17:52:08 +0200 + +USB devices use the DMA mask and offset of the controller, which have +already been setup when a device is probed. Note that modifying the +DMA mask of a USB device would change the mask for the controller (and +all devices on the bus) as the mask is literally shared. + +Since commit 2bf698671205 ("USB: of: fix root-hub device-tree node +handling"), of_dma_configure() would be called also for root hubs, which +use the device node of the controller. A separate, long-standing bug +that makes of_dma_configure() generate a 30-bit DMA mask from the RPI3's +"dma-ranges" would thus set a broken mask also for the controller. This +in turn prevents USB devices from enumerating when control transfers +fail: + + dwc2 3f980000.usb: Cannot do DMA to address 0x000000003a166a00 + +Note that the aforementioned DMA-mask bug was benign for the HCD itself +as the dwc2 driver overwrites the mask previously set by +of_dma_configure() for the platform device in its probe callback. The +mask would only later get corrupted when the root-hub child device was +probed. + +Fix this, and similar future problems, by adding a flag to struct device +which prevents driver core from calling dma_configure() during probe and +making sure it is set for USB devices. + +Fixes: 09515ef5ddad ("of/acpi: Configure dma operations at probe time for platform/amba/pci bus devices") +Cc: stable <stable@vger.kernel.org> # 4.12 +Cc: Robin Murphy <robin.murphy@arm.com> +Cc: Sricharan R <sricharan@codeaurora.org> +Cc: Stefan Wahren <stefan.wahren@i2se.com> +Reported-by: Hans Verkuil <hverkuil@xs4all.nl> +Signed-off-by: Johan Hovold <johan@kernel.org> +--- + +v3 + - add flag to struct device to prevent DMA configuration during probe instead + of checking for the USB bus type, which is not available when USB is built + as a module as noted by Alan + - drop moderated rpi list from CC + +v2 + - amend commit message and point out that the long-standing 30-bit DMA-mask + bug was benign to the dwc2 HCD itself (Robin) + - add and use a new dev_is_usb() helper (Robin) + + + drivers/base/dma-mapping.c | 6 ++++++ + drivers/usb/core/usb.c | 1 + + include/linux/device.h | 3 +++ + 3 files changed, 10 insertions(+) + +diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c +index b555ff9dd8fc..f9f703be0ad1 100644 +--- a/drivers/base/dma-mapping.c ++++ b/drivers/base/dma-mapping.c +@@ -345,6 +345,9 @@ int dma_configure(struct device *dev) + enum dev_dma_attr attr; + int ret = 0; + ++ if (dev->skip_dma_configure) ++ return 0; ++ + if (dev_is_pci(dev)) { + bridge = pci_get_host_bridge_device(to_pci_dev(dev)); + dma_dev = bridge; +@@ -369,6 +372,9 @@ int dma_configure(struct device *dev) + + void dma_deconfigure(struct device *dev) + { ++ if (dev->skip_dma_configure) ++ return; ++ + of_dma_deconfigure(dev); + acpi_dma_deconfigure(dev); + } +diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c +index 17681d5638ac..2a85d905b539 100644 +--- a/drivers/usb/core/usb.c ++++ b/drivers/usb/core/usb.c +@@ -588,6 +588,7 @@ struct usb_device *usb_alloc_dev(struct usb_device *parent, + * Note: calling dma_set_mask() on a USB device would set the + * mask for the entire HCD, so don't do that. + */ ++ dev->dev.skip_dma_configure = true; + dev->dev.dma_mask = bus->sysdev->dma_mask; + dev->dev.dma_pfn_offset = bus->sysdev->dma_pfn_offset; + set_dev_node(&dev->dev, dev_to_node(bus->sysdev)); +diff --git a/include/linux/device.h b/include/linux/device.h +index 723cd54b94da..022cf258068b 100644 +--- a/include/linux/device.h ++++ b/include/linux/device.h +@@ -877,6 +877,8 @@ struct dev_links_info { + * @offline: Set after successful invocation of bus type's .offline(). + * @of_node_reused: Set if the device-tree node is shared with an ancestor + * device. ++ * @skip_dma_configure: Set if driver core should not configure DMA for this ++ * device during probe. + * + * At the lowest level, every device in a Linux system is represented by an + * instance of struct device. The device structure contains the information +@@ -965,6 +967,7 @@ struct device { + bool offline_disabled:1; + bool offline:1; + bool of_node_reused:1; ++ bool skip_dma_configure:1; + }; + + static inline struct device *kobj_to_dev(struct kobject *kobj) |
