Hi, v1: https://lore.kernel.org/linux-nvme/20220321165049.35985-1-sven@xxxxxxxxxxxxx/T/ Thanks everyone for the reviews of v1! I've listed the changes in the individual commits to keep better track of them. And here's the v1 cover letter as a reference as well: This series includes everything[*] required to get NVMe up and running on Apple's M1, M1 Pro and M1 Max SoCs. The NVMe controller on these machines is not attached to a PCI bus and this driver originally started out when Arnd added platform support to pci.c and I added the required Apple quirks. Christoph Hellwig stumbled upon an early version and suggested to instead rewrite it as a stand-alone driver since some of these quirks are rather awkward to implement and would affect the hot path otherwise [1]. Here's the first version that creates apple.c to handle these weird NVMe controllers. The following parts are included: - Device tree bindings: Since this is the first and probably only SoC that has NVMe outside of a PCIe bus I've put them into soc/apple. The same bindings are also used by u-boot and OpenBSD already. - SART address filter: Some of the buffers required by the NVMe controller sit behind a simple DMA address filter Apple calls SART. It allows to specify up to 16 physical address ranges that are allowed and will reject access to anything else. Unlike a real IOMMU there's no way to setup pagetables and also not all buffers are subject to this filtering. Most buffers used by the NVMe commands themselves use an integrated IOMMU instead. - RTKit IPC protocol: The NVMe controller is running a proprietary RTOS Apple calls RTKit and we need to communicate with it in order to bring up and use the NVMe controller. This communication happens over a mailbox interface that is already upstream. This protocol is also used for various other drivers present on these SoCs (SMC, display controller, Thunderbolt/USB4). - And finally the NVMe driver itself: The driver registers a platform device and is mainly based on pci.c with a few special Apple quirks. The biggest difference to normal NVMe (except for the missing PCI bus) is that command submission works differently: The SQ is replaced with a simple array and a command is triggered by writing its tag to a MMIO register. Additionally, the command must also be setup in the proprietary NVMMU before it can be submitted. There is some code duplication with pci.c for the setup of the PRPs. Depending on what you prefer this could be moved to a common file shared between pci.c and apple.c. The hardware here is the same hardware that's already used in T2 Macs. The only difference is that the T2 chip itself initializes the controller, disable some quirks (the NVMMU and the weird submission array) and then exposes it over a PCIe interface. The driver itself has been successfully used by multiple people as their daily driver for weeks at this point and no major issues have been reported. A smaller issue is that flushes on the devices take *much* longer than expected. Jens Axboe has a workaround where the flushes are delayed but that one isn't ready for submission yet. Best, Sven [1] https://lore.kernel.org/linux-nvme/YRE7vCyn9d1ClhRm@xxxxxxxxxxxxx/ [*] The only missing part in this series are the device tree updates but since these will go through arm-soc anyway I haven't included them here but will instead submit them once this series is in a shape where it can be merged. Sven Peter (6): dt-bindings: iommu: Add Apple SART DMA address filter dt-bindings: nvme: Add Apple ANS NVMe soc: apple: Always include Makefile soc: apple: Add SART driver soc: apple: Add RTKit IPC library nvme-apple: Add initial Apple SoC NVMe driver .../devicetree/bindings/iommu/apple,sart.yaml | 52 + .../bindings/nvme/apple,nvme-ans.yaml | 111 ++ MAINTAINERS | 4 + drivers/nvme/host/Kconfig | 13 + drivers/nvme/host/Makefile | 3 + drivers/nvme/host/apple.c | 1597 +++++++++++++++++ drivers/soc/Makefile | 2 +- drivers/soc/apple/Kconfig | 24 + drivers/soc/apple/Makefile | 6 + drivers/soc/apple/rtkit-crashlog.c | 154 ++ drivers/soc/apple/rtkit-internal.h | 62 + drivers/soc/apple/rtkit.c | 958 ++++++++++ drivers/soc/apple/sart.c | 327 ++++ include/linux/soc/apple/rtkit.h | 159 ++ include/linux/soc/apple/sart.h | 57 + 15 files changed, 3528 insertions(+), 1 deletion(-) create mode 100644 Documentation/devicetree/bindings/iommu/apple,sart.yaml create mode 100644 Documentation/devicetree/bindings/nvme/apple,nvme-ans.yaml create mode 100644 drivers/nvme/host/apple.c create mode 100644 drivers/soc/apple/rtkit-crashlog.c create mode 100644 drivers/soc/apple/rtkit-internal.h create mode 100644 drivers/soc/apple/rtkit.c create mode 100644 drivers/soc/apple/sart.c create mode 100644 include/linux/soc/apple/rtkit.h create mode 100644 include/linux/soc/apple/sart.h -- 2.25.1
