grub/xhci: Add xHCI non-root-hub fixes from NitrokeyHEADmaster

See:
https://github.com/Nitrokey/nethsm-grub/commits/nethsm-z790?since=2025-01-13&until=2025-01-13

And more generally, see branch:
https://github.com/Nitrokey/nethsm-grub/commits/nethsm-z790

This brings in a few minor fixes, and also a not-so-minor fix:
Add TT (transaction translation) handling for non-SuperSpeed
devices in xhci.c

More generally, this patchset will improve non-root hub support
in the xHCI code. There is also a patch to work around a quirk
on the MSI Z790-P mainboard, which I'm planning to add to Libreboot
at a later date.

Signed-off-by: Leah Rowe <leah@libreboot.org>

1 files changed, 98 insertions, 0 deletions

diff --git a/config/grub/xhci/patches/0024-xhci-configure-TT-for-non-root-hubs.patch b/config/grub/xhci/patches/0024-xhci-configure-TT-for-non-root-hubs.patch
new file mode 100644
index 00000000..5f612885
--- /dev/null
+++ b/config/grub/xhci/patches/0024-xhci-configure-TT-for-non-root-hubs.patch
@@ -0,0 +1,98 @@
+From 7748bcc0e7cef17dbf626f83cc03e56a17075330 Mon Sep 17 00:00:00 2001
+From: Sven Anderson <sven@anderson.de>
+Date: Mon, 13 Jan 2025 20:26:32 +0100
+Subject: [PATCH 24/26] xhci: configure TT for non-root-hubs
+
+---
+ grub-core/bus/usb/usbhub.c |  6 +++++
+ grub-core/bus/usb/xhci.c   | 45 +++++++++++++++++++++++++++++++++-----
+ include/grub/usb.h         |  2 ++
+ 3 files changed, 47 insertions(+), 6 deletions(-)
+
+diff --git a/grub-core/bus/usb/usbhub.c b/grub-core/bus/usb/usbhub.c
+index e96505aa9..629b3ed53 100644
+--- a/grub-core/bus/usb/usbhub.c
++++ b/grub-core/bus/usb/usbhub.c
+@@ -818,3 +818,9 @@ grub_usb_iterate (grub_usb_iterate_hook_t hook, void *hook_data)
+ 
+   return 0;
+ }
++
++grub_usb_device_t
++grub_usb_get_dev (int addr)
++{
++  return grub_usb_devs[addr];
++}
+diff --git a/grub-core/bus/usb/xhci.c b/grub-core/bus/usb/xhci.c
+index d13a7c39d..8ad2a10f9 100644
+--- a/grub-core/bus/usb/xhci.c
++++ b/grub-core/bus/usb/xhci.c
+@@ -623,13 +623,46 @@ grub_xhci_alloc_inctx(struct grub_xhci *x, int maxepid,
+       break;
+   }
+ 
+-  /* Route is greater zero on devices that are connected to a non root hub */
+-  if (dev->route)
+-    {
+-      /* FIXME: Implement this code for non SuperSpeed hub devices */
++  /* Set routing string */
++  slot->ctx[0] |= dev->route;
++
++  /* Set root hub port number */
++  slot->ctx[1] |= (dev->root_port + 1) << 16;
++
++  if (dev->split_hubaddr && (dev->speed == GRUB_USB_SPEED_LOW ||
++                            dev->speed == GRUB_USB_SPEED_FULL)) {
++
++    grub_usb_device_t hubdev = grub_usb_get_dev(dev->split_hubaddr);
++
++    if (!hubdev || hubdev->descdev.class != GRUB_USB_CLASS_HUB) {
++      grub_dprintf("xhci", "Invalid hub device at addr %d!\n", dev->split_hubaddr);
++      return NULL;
++    }
++
++    struct grub_xhci_priv *hub_priv = hubdev->xhci_priv;
++    if (!hub_priv) {
++      grub_dprintf("xhci", "Hub has no xhci_priv!\n"); 
++      return NULL;
++    }
++
++    if (hubdev->speed == GRUB_USB_SPEED_HIGH) {
++      /* Direct connection to high-speed hub - set up TT */
++      grub_dprintf("xhci", "Direct high-speed hub connection - configuring TT with "
++                   "hub slot %d port %d\n", hub_priv->slotid, dev->split_hubport);
++      slot->ctx[2] |= hub_priv->slotid;
++      slot->ctx[2] |= dev->split_hubport << 8;
+     }
+-  slot->ctx[0]    |= dev->route;
+-  slot->ctx[1]    |= (dev->root_port+1) << 16;
++    else {
++      /* Hub is not high-speed, inherit TT settings from parent */
++      volatile struct grub_xhci_slotctx *hubslot;
++      grub_dprintf("xhci", "Non high-speed hub - inheriting TT settings from parent\n");
++      hubslot = grub_dma_phys2virt(x->devs[hub_priv->slotid].ptr_low, x->devs_dma);
++      slot->ctx[2] = hubslot->ctx[2];
++    }
++  }
++
++  grub_dprintf("xhci", "Slot context: ctx[0]=0x%08x ctx[1]=0x%08x ctx[2]=0x%08x\n",
++               slot->ctx[0], slot->ctx[1], slot->ctx[2]);
+ 
+   grub_arch_sync_dma_caches(in, size);
+ 
+diff --git a/include/grub/usb.h b/include/grub/usb.h
+index eb71fa1c7..df97a60cc 100644
+--- a/include/grub/usb.h
++++ b/include/grub/usb.h
+@@ -62,6 +62,8 @@ typedef int (*grub_usb_controller_iterate_hook_t) (grub_usb_controller_t dev,
+ /* Call HOOK with each device, until HOOK returns non-zero.  */
+ int grub_usb_iterate (grub_usb_iterate_hook_t hook, void *hook_data);
+ 
++grub_usb_device_t grub_usb_get_dev (int addr);
++
+ grub_usb_err_t grub_usb_device_initialize (grub_usb_device_t dev);
+ 
+ grub_usb_err_t grub_usb_get_descriptor (grub_usb_device_t dev,
+-- 
+2.39.5
+