Changeset 9b56e528 in mainline for uspace/drv/bus/usb/xhci/rh.c

Timestamp:

2018-01-13T15:13:44Z (6 years ago)

Author:

Ondřej Hlavatý <aearsis@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

36fb6d7

Parents:

37b13175

git-author:

Ondřej Hlavatý <aearsis@…> (2018-01-13 15:11:45)

git-committer:

Ondřej Hlavatý <aearsis@…> (2018-01-13 15:13:44)

Message:

xhci rh: better not disable port on any event

The result of a long debugging is that PED bit is RW1C, which means
that enabled port disables itself when asserting events.

File:

• uspace/drv/bus/usb/xhci/rh.c (modified) (4 diffs)

uspace/drv/bus/usb/xhci/rh.c

@@ -52 +52 @@
 
 /* This mask only lists registers, which imply port change. */
-static const uint32_t port_change_mask =
+static const uint32_t port_events_mask =
         XHCI_REG_MASK(XHCI_PORT_CSC) |
         XHCI_REG_MASK(XHCI_PORT_PEC) |
@@ -162 +162 @@
         int err;
         assert(rh);
-
         assert(rh->devices_by_port[port_id - 1] == NULL);
+
+        if (!XHCI_REG_RD(&rh->hc->op_regs->portrs[port_id - 1], XHCI_PORT_PED)) {
+                usb_log_error("Cannot setup RH device: port is disabled.");
+                return EIO;
+        }
 
         device_t *dev = hcd_ddf_fun_create(&rh->hc->base);
@@ -322 +326 @@
         xhci_port_regs_t * const regs = &rh->hc->op_regs->portrs[port_id - 1];
 
-        uint32_t events = XHCI_REG_RD_FIELD(&regs->portsc, 32) & port_change_mask;
+        uint32_t events = XHCI_REG_RD_FIELD(&regs->portsc, 32) & port_events_mask;
 
         while (events) {
-                XHCI_REG_SET_FIELD(&regs->portsc, events, 32);
+                /*
+                 * The PED bit in xHCI has RW1C semantics, which means that
+                 * writing 1 to it will disable the port. Which means all
+                 * standard mechanisms of register handling fails here.
+                 */
+                uint32_t portsc = XHCI_REG_RD_FIELD(&regs->portsc, 32);
+                portsc &= ~(port_events_mask | XHCI_REG_MASK(XHCI_PORT_PED)); // Clear events + PED
+                portsc |= events; // Add back events to assert them
+                XHCI_REG_WR_FIELD(&regs->portsc, portsc, 32);
 
                 if (events & XHCI_REG_MASK(XHCI_PORT_CSC)) {
@@ -346 +358 @@
                 
                 /* Make sure that PSCEG is 0 before exiting the loop. */
-                events = XHCI_REG_RD_FIELD(&regs->portsc, 32) & port_change_mask;
+                events = XHCI_REG_RD_FIELD(&regs->portsc, 32) & port_events_mask;
         }