Hi Mathias,
On 10/4/2023 7:02 AM, Mathias Nyman wrote:
On 2.10.2023 23.07, Wesley Cheng wrote:
Hi Mathias,
On 9/28/2023 3:31 AM, Mathias Nyman wrote:
On 22.9.2023 0.48, Wesley Cheng wrote:
From: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Modify the XHCI drivers to accommodate for handling multiple event
rings in
case there are multiple interrupters. Add the required APIs so
clients are
able to allocate/request for an interrupter ring, and pass this
information
back to the client driver. This allows for users to handle the
resource
accordingly, such as passing the event ring base address to an audio
DSP.
There is no actual support for multiple MSI/MSI-X vectors.
Factoring out XHCI interrupter APIs and structures done by Wesley
Cheng, in
order to allow for USB class drivers to utilze them.
}
+void xhci_remove_secondary_interrupter(struct usb_hcd *hcd, struct
xhci_interrupter *ir)
+{
+ struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+ unsigned int intr_num;
+
+ /* interrupter 0 is primary interrupter, don't touchit */
+ if (!ir || !ir->intr_num || ir->intr_num >=
xhci->max_interrupters) {
+ xhci_dbg(xhci, "Invalid secondary interrupter, can't
remove\n");
+ return;
+ }
+
+ /* fixme, should we check xhci->interrupter[intr_num] == ir */
+ spin_lock(&xhci->lock);
Needs to be spin_lock_irq() ir spin_lock_irqsave() as xhci->lock is
used in interrupt handler.
+ intr_num = ir->intr_num;
+ xhci_free_interrupter(xhci, ir);
+ xhci->interrupters[intr_num] = NULL;
+ spin_unlock(&xhci->lock);
likewise
Let me check these again. In general, I think I will use both the
xhci->mutex and xhci->lock where needed, because I believe we'd run
into sleep while atomic issues
while freeing the DMA memory. Will rework this and submit in the next
rev.
Maybe we need to split xhci_free_interrupter() into separate remove and
free functions
Thanks for sharing the work you've been doing. Yes, I did something
similar as well on my end, but will refactor in your code and re-test.
Did some work on this, and on the sideband api in general.
Code still has a lot of FIXMEs, and it's completely untested, but to
avoid us
from doing duplicate work I pushed it to my feature_interrupters branch
anyway
git://git.kernel.org/pub/scm/linux/kernel/git/mnyman/xhci.git
feature_interrupters
https://git.kernel.org/pub/scm/linux/kernel/git/mnyman/xhci.git/log/?h=feature_interrupters
Ok. Initial look at it seems like it will be fine, but will integrate
and make changes where needed.
Thanks
Wesley Cheng