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fix(usb/ehci): correct the USBCMD and PORTSC bit definitions - #105
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FengHeting merged 3 commits intoOct 20, 2026
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Two groups of EHCI register bits did not match EHCI 1.0 (sections 2.3.1
and 2.3.9) or Linux's include/linux/usb/ehci_def.h:
USBCMD ASE bit 2 -> bit 5 (bits 3:2 are Frame List Size)
PSE bit 3 -> bit 4
PORTSC CSC bit 17 -> bit 1 (bits 19:16 are Port Test Control)
PED bit 1 -> bit 2
PEC bit 18 -> bit 3
Together they kept every EHCI device from enumerating:
- After the port reset, ehci_port_reset() tested "PED" but read CSC,
which the worker had already cleared, so a high-speed device looked
not enabled and the port was handed to the companion (-ENODEV).
- With that fixed, "ASE" landed in the Frame List Size field, which
QEMU rejects ("attempt to set frame list size"), so the async
schedule never started and the first SET_ADDRESS timed out
(-ETIMEDOUT).
Tested in QEMU (q35, usb-ehci + usb-storage): before, "usb-ehci: Port
0 enumeration failed: -19" and no /dev/sda; with only the PORTSC fix,
-110; with both, /dev/sda appears.
Signed-off-by: JiTianYu391 <[email protected]>
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Rainy101112
previously approved these changes
Oct 18, 2026
EHCI_CMD_ASYNC was defined at USBCMD bit 8, but bits 9:8 are the park mode count and the park enable is bit 11. Replace it with the park count field and EHCI_CMD_PARK. EHCI_PORT_PTC_SHIFT pointed at bits 6:3 instead of the port test control field at bits 19:16, so it overlapped PEC, OCA, OCC and FPR. The QH endpoint-capability block defined C at bits 1:0 and RL at bits 7:4. Neither field exists there: C is the control endpoint flag at bit 27 (already covered by EHCI_QH_CONTROL) and RL is the NAK counter reload at bits 31:28. Drop the bogus pair and give RL its real field. EHCI_HCS_NCC and EHCI_HCS_NPCC were named the wrong way round: bits 11:8 are N_PCC and bits 15:12 are N_CC. None of the corrected macros had users, so no generated code changes. Signed-off-by: MicroFish <[email protected]> Co-Authored-By: Claude Code <[email protected]>
clang-format lines up the USBCMD macros with the longer park count field added by the previous change. Signed-off-by: MicroFish <[email protected]>
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问题
include/drivers/usb/host/ehci/ehci.h里两组寄存器位与 EHCI 1.0 规范（2.3.1 / 2.3.9）以及 Linuxinclude/linux/usb/ehci_def.h不一致，导致 EHCI 上的任何设备都无法枚举。故障链
ehci_port_reset()检查"PED"，实际读到的是 CSC（已被 worker 清掉），于是把高速设备误判为"未使能"，置 PO 交给伴随控制器 →Port 0 enumeration failed: -19。hcd-ehci.c: attempt to set frame list size），异步调度从未启动，第一个 SET_ADDRESS 超时 →-110。两处缺一不可。只改头文件，
ehci.c无改动。测试（QEMU q35，
usb-ehci+usb-storage）enumeration failed: -19，无/dev/sdaenumeration failed: -110enumeration failed: -19/dev/sda出现QEMU trace（修复前）：内核写
USBCMD = 0x5，QEMU 记录为0x1，ASE 被丢弃。备注
EHCI_PORT_PTC_*的位置也不对，但没有任何代码使用，为保持改动最小未动。CONFIG_VIRTIO_GPU：当前 develop 的virtgpu_vq.c有static ratelimit重定义编译错误，与本 PR 无关。🤖 Generated with Claude Code