I’m writing an x86_64 OS and testing it on qemu pc. I’m trying to make a very minimal and rough implementation of an xHCI driver, to read from the usb stick I use for booting. I have located the MMIO space of the controller and checked that the values in it are reasonable. Then, I extracted from it some offsets to the various data structures. I start from the assumption that UEFI firmware has already setup the controller and enumerate the USB devices attached to it (which seems to be the case since I can see a valid device context pointer at index 1 of the device context base address array). I checked the state of the endpoints offered by device 1, and found 3 endpoints (as I expected):

I’m writing an x86_64 OS and testing it on qemu pc. I’m trying to make a very minimal and rough implementation of an xHCI driver, to read from the usb stick I use for booting. I have located the MMIO space of the controller and checked that the values in it are reasonable. Then, I extracted from it some offsets to the various data structures. I start from the assumption that UEFI firmware has already setup the controller and enumerate the USB devices attached to it (which seems to be the case since I can see a valid device context pointer at index 1 of the device context base address array). I checked the state of the endpoints offered by device 1, and found 3 endpoints (as I expected):

I’m writing an x86_64 OS and testing it on qemu pc. I’m trying to make a very minimal and rough implementation of an xHCI driver, to read from the usb stick I use for booting. I have located the MMIO space of the controller and checked that the values in it are reasonable. Then, I extracted from it some offsets to the various data structures. I start from the assumption that UEFI firmware has already setup the controller and enumerate the USB devices attached to it (which seems to be the case since I can see a valid device context pointer at index 1 of the device context base address array). I checked the state of the endpoints offered by device 1, and found 3 endpoints (as I expected):

I’m writing an x86_64 OS and testing it on qemu pc. I’m trying to make a very minimal and rough implementation of an xHCI driver, to read from the usb stick I use for booting. I have located the MMIO space of the controller and checked that the values in it are reasonable. Then, I extracted from it some offsets to the various data structures. I start from the assumption that UEFI firmware has already setup the controller and enumerate the USB devices attached to it (which seems to be the case since I can see a valid device context pointer at index 1 of the device context base address array). I checked the state of the endpoints offered by device 1, and found 3 endpoints (as I expected):

I’m writing an x86_64 OS and testing it on qemu pc. I’m trying to make a very minimal and rough implementation of an xHCI driver, to read from the usb stick I use for booting. I have located the MMIO space of the controller and checked that the values in it are reasonable. Then, I extracted from it some offsets to the various data structures. I start from the assumption that UEFI firmware has already setup the controller and enumerate the USB devices attached to it (which seems to be the case since I can see a valid device context pointer at index 1 of the device context base address array). I checked the state of the endpoints offered by device 1, and found 3 endpoints (as I expected):