UHCI: do not deactivate TDs on NAKs

[Cacodemon345]

NAKs from USB devices do not deactivate TDs according to the official UHCI spec (page 22).

Reference: http://ftp.netbsd.org/pub/NetBSD/misc/blymn/uhci11d.pdf

[fysnet]

I think this PR is valid.

The only thing I think I would do different, is add another field to the set_status() call, sending a 1 to keep the active bit set, and a 0 to clear it. This way, if we find another reference where this is the case, a simple change of a single digit is all that is needed. Since there are only three calls to this function, and they are all within a couple of lines of each other, this addition may be overkill though.

[fysnet]

It's dword1 not dword2 though.

I would do something similar to:

--- uhci_core.h         2024-10-19 16:44:23.161155600 -0700
+++ uhci_core.h        2024-10-19 16:40:21.021583600 -0700
@@ -215,7 +215,7 @@
   static void uhci_timer_handler(void *);
   void uhci_timer(void);
   bool DoTransfer(Bit32u address, struct TD *);
-  void set_status(struct TD *td, bool stalled, bool data_buffer_error, bool babble,
+  void set_status(struct TD *td, bool active, bool stalled, bool data_buffer_error, bool babble,
     bool nak, bool crc_time_out, bool bitstuff_error, Bit16u act_len);

   static Bit32u read_handler(void *this_ptr, Bit32u address, unsigned io_len);

--- uhci_core.cc        2024-10-19 16:44:02.468873800 -0700
+++ uhci_core.cc       2024-10-19 16:41:08.843534900 -0700
@@ -1009,11 +1009,11 @@
     }
   }
   if (ret >= 0) {
-    set_status(td, 0, 0, 0, 0, 0, 0, len-1);
+    set_status(td, 0, 0, 0, 0, 0, 0, 0, len-1);
   } else if (ret == USB_RET_NAK) {
-    set_status(td, 0, 0, 0, 1, 0, 0, len-1); // NAK
+    set_status(td, 1, 0, 0, 0, 1, 0, 0, len-1); // NAK
   } else {
-    set_status(td, 1, 0, 0, 0, 0, 0, 0x007); // stalled
+    set_status(td, 0, 1, 0, 0, 0, 0, 0, 0x007); // stalled
   }
   remove_async_packet(&packets, p);
   return 1;
@@ -1032,13 +1032,14 @@
 }

 // If the request fails, set the stall bit ????
-void bx_uhci_core_c::set_status(struct TD *td, bool stalled, bool data_buffer_error, bool babble,
+void bx_uhci_core_c::set_status(struct TD *td, bool active, bool stalled, bool data_buffer_error, bool babble,
                              bool nak, bool crc_time_out, bool bitstuff_error, Bit16u act_len)
 {
   // clear out the bits we can modify and/or want zero
   td->dword1 &= 0xDF00F800;

   // now set the bits according to the passed param's
+  td->dword1 |= active            ? (1<<23) : 0; // active
   td->dword1 |= stalled           ? (1<<22) : 0; // stalled
   td->dword1 |= data_buffer_error ? (1<<21) : 0; // data buffer error
   td->dword1 |= babble            ? (1<<20) : 0; // babble
@@ -1050,7 +1051,6 @@
     td->dword1 &= ~((1<<28) | (1<<27));  // clear the c_err field if there was an error
 }

-
 // pci configuration space write callback handler
 void bx_uhci_core_c::pci_write_handler(Bit8u address, Bit32u value, unsigned io_len)
 {

[vruppert]

Please update PR based on Ben's suggestion.

[Cacodemon345]

Done.