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| author | Orgad Shaneh <orgads@gmail.com> | 2026-09-01 19:30:28 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-09-10 17:07:55 +0200 |
| commit | 22bce6d2b3fd9e845d71e0037b6929913301462d (patch) | |
| tree | ae4e2b3b87559211287e1b2d10fbd751516d8e1a | |
| parent | 4c7a1b9f1f1979f2b3b69428ada12680695159c2 (diff) | |
| download | linux-next-22bce6d2b3fd9e845d71e0037b6929913301462d.tar.gz linux-next-22bce6d2b3fd9e845d71e0037b6929913301462d.zip | |
usb: octeon-hcd: fail the probe when the USB core does not respond
If the USBN clock/PHY setup did not actually bring the core up (wrong
board reference-clock configuration, for instance), every USBC CSR
reads as all-ones and initialization marches on programming garbage,
ending in timeouts or a wedge deep in the FIFO flush.
Read GHWCFG3 - a hardwired configuration register that can be neither
0 nor all-ones on a live core - right before core initialization, and
give up cleanly if the core is not answering.
Assisted-by: Claude:claude-opus-5
Signed-off-by: Orgad Shaneh <orgads@gmail.com>
Link: https://patch.msgid.link/20260901193100.1352110-2-orgads@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/host/octeon-hcd.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/usb/host/octeon-hcd.c b/drivers/usb/host/octeon-hcd.c index 7d121909f514..5a846c3fc34a 100644 --- a/drivers/usb/host/octeon-hcd.c +++ b/drivers/usb/host/octeon-hcd.c @@ -853,6 +853,14 @@ retry: * USBC_GAHBCFG[PTXFEMPLVL] * Global interrupt mask, USBC_GAHBCFG[GLBLINTRMSK] = 1 */ + usbcx_gahbcfg.u32 = cvmx_usb_read_csr32(usb, + CVMX_USBCX_GHWCFG3(usb->index)); + if (usbcx_gahbcfg.u32 == 0xffffffff || usbcx_gahbcfg.u32 == 0) { + dev_err(dev, "USB core is not responding (GHWCFG3=0x%08x)\n", + usbcx_gahbcfg.u32); + return -ENODEV; + } + usbcx_gahbcfg.u32 = 0; usbcx_gahbcfg.s.dmaen = !(usb->init_flags & CVMX_USB_INITIALIZE_FLAGS_NO_DMA); |