Unnamed repository; edit this file 'description' to name the repository. http://cgit.235523.xyz/tinyusb.git/atom/src/portable/ohci/ohci.h?h=codex%2Fclass-reference-docs 2026-07-02T14:55:45Z 2026-07-02T14:55:45Z Ha Thach thach@tinyusb.org 2026-07-02T14:55:45Z urn:sha1:7a4111b96ef6279e75579f9a18443834f6a0871d * license: use SPDX identifiers for src/ headers Replace the full ~20-line MIT license boilerplate on every src/ file with a two-line SPDX tag (SPDX-FileCopyrightText + SPDX-License-Identifier), following the REUSE convention used by CircuitPython and the Linux kernel. Removes ~3500 lines of duplicated boilerplate. 2025-10-31T07:21:17Z hathach thach@tinyusb.org 2025-10-31T07:21:17Z urn:sha1:6837e47584d2512c8251345e09775075f8159c4d 2025-10-30T07:35:11Z hathach thach@tinyusb.org 2025-10-30T06:59:25Z urn:sha1:88305b1b34160b4548609b78807be910944856ab # Conflicts: - hw/bsp/lpc17/family.cmake - hw/bsp/lpc40/family.cmake - hw/bsp/lpc55/family.cmake 2025-10-28T07:14:01Z hathach thach@tinyusb.org 2025-10-28T06:21:38Z urn:sha1:d92b810df7670aae0e195fd02abef5014470c2f7 fix compiling with nuc family 2025-10-10T06:47:41Z hathach thach@tinyusb.org 2025-10-10T05:33:41Z urn:sha1:83baf13dcbde66942419c03348cc88ef22575e32 2025-10-09T11:50:04Z hathach thach@tinyusb.org 2025-10-09T11:50:04Z urn:sha1:cc82e088b5333bae3dba8fb12965271d89cd5117 2025-10-09T11:18:08Z hathach thach@tinyusb.org 2025-10-09T11:18:08Z urn:sha1:d4374bb0dbb0e0eddd4459219f981fd8f62365a1 2025-09-13T21:05:04Z R rqou@berkeley.edu 2025-09-12T23:41:15Z urn:sha1:b9378eb8e79691907aae40b3fc26cb57d4ffaeb4 This code is written very carefully to always use an uncached view of memory to read/write EDs. An uncached view must *always* be used, or else cache behavior can corrupt the ED. As part of this change, combine access into as few word-sized accesses as possible. This makes the code perform better. Doing this involves giving type names to the bitfields that make up the ED's data words. 2025-09-12T23:11:02Z R rqou@berkeley.edu 2025-09-12T22:33:47Z urn:sha1:330d9d7f426b3227149e76fc7dd167e2cd3745ad The initial motivation for doing this is to remove the `used` flag in the TD. If we use this flag, we end up being required to read from TDs that the OHCI controller might be modifying (i.e. the OHCI controller logically owns the TD). This happens when we try to allocate a new, empty TD while the OHCI host controller is working on a transfer. Move the `used` flag to `gtd_extra_data_t`. This data is only used by the CPU, and the OHCI controller never accesses it. The existing allocation method for TDs does *not* put an empty TD onto each ED (i.e it does *not* do what is shown in Figure 5-6 of the OHCI specification). Instead, the NextTD field of the last TD is set to 0. The TailP field of the ED is also set to 0. This works in many cases. However, this implementation means that the CPU may end up trying to write to the NextTD field of an in-progress transfer while the OHCI host controller logically owns it. Change the implementation to use an empty TD, as suggested by the specification, for endpoints other than EP0. This avoids the above issue. It is not necessary to make the change for EP0 because only at most one TD can ever be pending at a time. The above change should also remove the need for the stall workaround. In the future, we want to modify the code to access EDs through an uncached mapping. Because uncached mappings are slow, we want to access EDs as little as possible. Currently, when a TD completes, we access an ED in order to figure out the device address and endpoint number of the TD which was completed. Because moving `used` to `gtd_extra_data_t` necessitates expanding it, we have enough room to also store the device address and endpoint number of the TD. This patch does so. With the above two changes, we no longer need to access an ED when a TD completes. Also remove the `index` field from TDs as it is no longer necessary. 2025-09-12T21:17:10Z R rqou@berkeley.edu 2025-09-12T21:16:46Z urn:sha1:839149c5c0b667a8080de39c85cdbdd291be4dc5