3 files changed, 114 insertions, 3 deletions
diff --git a/src/sys/include/io/usb/xhciregs.h b/src/sys/include/io/usb/xhciregs.h
index f2e572b..f849c54 100644
--- a/src/sys/include/io/usb/xhciregs.h
+++ b/src/sys/include/io/usb/xhciregs.h
@@ -32,6 +32,7 @@
 
 #include <sys/types.h>
 #include <sys/cdefs.h>
+#include <sys/param.h>
 
 /*
  * XHCI capability registers
@@ -69,4 +70,17 @@ struct __packed xhci_opregs {
     volatile uint32_t reserved2;
 };
 
+/*
+ * USB command register bits
+ *
+ * See section 5.4.1 of the xHCI spec
+ */
+#define USBCMD_HCRST BIT(1)
+
+/*
+ * Macros to get various register spaces
+ */
+#define XHCI_OPBASE(CAPBASE) \
+    PTR_OFFSET(CAPBASE, (CAPBASE)->caplength)
+
 #endif  /* !_XHCIREGS_H_ */
diff --git a/src/sys/include/io/usb/xhcivar.h b/src/sys/include/io/usb/xhcivar.h
index 5067063..c0b3a39 100644
--- a/src/sys/include/io/usb/xhcivar.h
+++ b/src/sys/include/io/usb/xhcivar.h
@@ -39,7 +39,9 @@
  * @io: I/O space
  */
 struct xhci_hcd {
-    volatile void *io;
+    struct xhci_capregs *capspace;
 };
 
+#define XHCI_TIMEOUT_MSEC 500
+
 #endif  /* !_USB_XHCIVAR_H_ */
diff --git a/src/sys/io/usb/hcd/xhci.c b/src/sys/io/usb/hcd/xhci.c
index 4cfbdc5..8d3b0a0 100644
--- a/src/sys/io/usb/hcd/xhci.c
+++ b/src/sys/io/usb/hcd/xhci.c
@@ -32,6 +32,7 @@
 #include <sys/errno.h>
 #include <os/bus.h>
 #include <os/mmio.h>
+#include <os/clkdev.h>
 #include <io/usb/xhcivar.h>
 #include <io/usb/xhciregs.h>
 #include <io/pci/bar.h>
@@ -48,12 +49,106 @@
 static struct pci_adv adv;
 static struct pci_device dev;
 static struct xhci_hcd hcd;
+static struct clkdev *clk;
+
+/*
+ * Poll a register until it is either set or unset
+ *
+ * @reg: Register pointer to poll
+ * @mask: Mask to poll
+ * @pollset: If true, poll until set
+ */
+static int
+xhci_poll32(volatile uint32_t *reg, uint32_t mask, bool pollset)
+{
+    uint16_t msec = 0;
+    uint32_t v, tmp;
+
+    if (reg == NULL) {
+        return -EINVAL;
+    }
+
+    for (;;) {
+        if (msec >= XHCI_TIMEOUT_MSEC) {
+            break;
+        }
+
+        v = mmio_read32(reg);
+        v &= mask;
+
+        if (pollset && v == mask)
+            return 0;
+        if (!pollset && v == 0)
+            return 0;
+
+        clk->msleep(1);
+        ++msec;
+    }
+
+    return -ETIME;
+}
+
+/*
+ * Perform a hard host controller reset
+ */
+static int
+xhci_reset_hc(struct xhci_hcd *hcd)
+{
+    struct xhci_opregs *opregs;
+    uint32_t usbcmd;
+    int error;
+
+    if (hcd == NULL) {
+        return -EINVAL;
+    }
+
+    opregs = XHCI_OPBASE(hcd->capspace);
+
+    /* Reset the controller */
+    usbcmd = mmio_read32(&opregs->usbcmd);
+    usbcmd |= USBCMD_HCRST;
+    mmio_write32(&opregs->usbcmd, usbcmd);
+
+    /* Wait for it to be done */
+    error = xhci_poll32(&opregs->usbcmd, USBCMD_HCRST, false);
+    if (error < 0) {
+        pr_trace("failed to initialize controller\n");
+        return error;
+    }
+
+    return 0;
+}
+
+/*
+ * Initialize the host controller
+ */
+static int
+xhci_init_hc(struct xhci_hcd *hcd)
+{
+    struct xhci_opregs *opregs;
+    uint32_t usbcmd;
+    int error;
+
+    if (hcd == NULL) {
+        return -EINVAL;
+    }
+
+    if ((error = xhci_reset_hc(hcd)) < 0) {
+        return error;
+    }
+    return 0;
+}
 
 static int
 xhci_init(struct module *modp)
 {
     int error;
 
+    error = clkdev_get(CLKDEV_MSLEEP | CLKDEV_GET_USEC, &clk);
+    if (error < 0) {
+        return error;
+    }
+
     if ((error = pci_advoc(&adv)) < 0) {
         return error;
     }
@@ -84,8 +179,8 @@ xhci_attach(struct pci_adv *ap)
         return error;
     }
 
-    hcd.io = bs.va_base;
-    return 0;
+    hcd.capspace = bs.va_base;
+    return xhci_init_hc(&hcd);
 }
 
 static struct pci_adv adv = {