symbian-qemu-0.9.1-12/qemu-symbian-svp/hw/usb-uhci.c
changeset 1 2fb8b9db1c86
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/qemu-symbian-svp/hw/usb-uhci.c	Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,1145 @@
+/*
+ * USB UHCI controller emulation
+ *
+ * Copyright (c) 2005 Fabrice Bellard
+ *
+ * Copyright (c) 2008 Max Krasnyansky
+ *     Magor rewrite of the UHCI data structures parser and frame processor
+ *     Support for fully async operation and multiple outstanding transactions
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include "hw.h"
+#include "usb.h"
+#include "pci.h"
+#include "qemu-timer.h"
+
+//#define DEBUG
+//#define DEBUG_DUMP_DATA
+
+#define UHCI_CMD_FGR      (1 << 4)
+#define UHCI_CMD_EGSM     (1 << 3)
+#define UHCI_CMD_GRESET   (1 << 2)
+#define UHCI_CMD_HCRESET  (1 << 1)
+#define UHCI_CMD_RS       (1 << 0)
+
+#define UHCI_STS_HCHALTED (1 << 5)
+#define UHCI_STS_HCPERR   (1 << 4)
+#define UHCI_STS_HSERR    (1 << 3)
+#define UHCI_STS_RD       (1 << 2)
+#define UHCI_STS_USBERR   (1 << 1)
+#define UHCI_STS_USBINT   (1 << 0)
+
+#define TD_CTRL_SPD     (1 << 29)
+#define TD_CTRL_ERROR_SHIFT  27
+#define TD_CTRL_IOS     (1 << 25)
+#define TD_CTRL_IOC     (1 << 24)
+#define TD_CTRL_ACTIVE  (1 << 23)
+#define TD_CTRL_STALL   (1 << 22)
+#define TD_CTRL_BABBLE  (1 << 20)
+#define TD_CTRL_NAK     (1 << 19)
+#define TD_CTRL_TIMEOUT (1 << 18)
+
+#define UHCI_PORT_RESET (1 << 9)
+#define UHCI_PORT_LSDA  (1 << 8)
+#define UHCI_PORT_ENC   (1 << 3)
+#define UHCI_PORT_EN    (1 << 2)
+#define UHCI_PORT_CSC   (1 << 1)
+#define UHCI_PORT_CCS   (1 << 0)
+
+#define FRAME_TIMER_FREQ 1000
+
+#define FRAME_MAX_LOOPS  100
+
+#define NB_PORTS 2
+
+#ifdef DEBUG
+#define dprintf printf
+
+const char *pid2str(int pid)
+{
+    switch (pid) {
+    case USB_TOKEN_SETUP: return "SETUP";
+    case USB_TOKEN_IN:    return "IN";
+    case USB_TOKEN_OUT:   return "OUT";
+    }
+    return "?";
+}
+
+#else
+#define dprintf(...)
+#endif
+
+#ifdef DEBUG_DUMP_DATA
+static void dump_data(const uint8_t *data, int len)
+{
+    int i;
+
+    printf("uhci: data: ");
+    for(i = 0; i < len; i++)
+        printf(" %02x", data[i]);
+    printf("\n");
+}
+#else
+static void dump_data(const uint8_t *data, int len) {}
+#endif
+
+/* 
+ * Pending async transaction.
+ * 'packet' must be the first field because completion
+ * handler does "(UHCIAsync *) pkt" cast.
+ */
+typedef struct UHCIAsync {
+    USBPacket packet;
+    struct UHCIAsync *next;
+    uint32_t  td;
+    uint32_t  token;
+    int8_t    valid;
+    uint8_t   done;
+    uint8_t   buffer[2048];
+} UHCIAsync;
+
+typedef struct UHCIPort {
+    USBPort port;
+    uint16_t ctrl;
+} UHCIPort;
+
+typedef struct UHCIState {
+    PCIDevice dev;
+    uint16_t cmd; /* cmd register */
+    uint16_t status;
+    uint16_t intr; /* interrupt enable register */
+    uint16_t frnum; /* frame number */
+    uint32_t fl_base_addr; /* frame list base address */
+    uint8_t sof_timing;
+    uint8_t status2; /* bit 0 and 1 are used to generate UHCI_STS_USBINT */
+    QEMUTimer *frame_timer;
+    UHCIPort ports[NB_PORTS];
+
+    /* Interrupts that should be raised at the end of the current frame.  */
+    uint32_t pending_int_mask;
+
+    /* Active packets */
+    UHCIAsync *async_pending;
+    UHCIAsync *async_pool;
+} UHCIState;
+
+typedef struct UHCI_TD {
+    uint32_t link;
+    uint32_t ctrl; /* see TD_CTRL_xxx */
+    uint32_t token;
+    uint32_t buffer;
+} UHCI_TD;
+
+typedef struct UHCI_QH {
+    uint32_t link;
+    uint32_t el_link;
+} UHCI_QH;
+
+static UHCIAsync *uhci_async_alloc(UHCIState *s)
+{
+    UHCIAsync *async = qemu_malloc(sizeof(UHCIAsync));
+    if (async) {
+        memset(&async->packet, 0, sizeof(async->packet));
+        async->valid = 0;
+        async->td    = 0;
+        async->token = 0;
+        async->done  = 0;
+        async->next  = NULL;
+    }
+
+    return async;
+}
+
+static void uhci_async_free(UHCIState *s, UHCIAsync *async)
+{
+    qemu_free(async);
+}
+
+static void uhci_async_link(UHCIState *s, UHCIAsync *async)
+{
+    async->next = s->async_pending;
+    s->async_pending = async;
+}
+
+static void uhci_async_unlink(UHCIState *s, UHCIAsync *async)
+{
+    UHCIAsync *curr = s->async_pending;
+    UHCIAsync **prev = &s->async_pending;
+
+    while (curr) {
+	if (curr == async) {
+            *prev = curr->next;
+            return;
+        }
+
+        prev = &curr->next;
+        curr = curr->next;
+    }
+}
+
+static void uhci_async_cancel(UHCIState *s, UHCIAsync *async)
+{
+    dprintf("uhci: cancel td 0x%x token 0x%x done %u\n",
+           async->td, async->token, async->done);
+
+    if (!async->done)
+        usb_cancel_packet(&async->packet);
+    uhci_async_free(s, async);
+}
+
+/*
+ * Mark all outstanding async packets as invalid.
+ * This is used for canceling them when TDs are removed by the HCD.
+ */
+static UHCIAsync *uhci_async_validate_begin(UHCIState *s)
+{
+    UHCIAsync *async = s->async_pending;
+
+    while (async) {
+        async->valid--;
+        async = async->next;
+    }
+    return NULL;
+}
+
+/*
+ * Cancel async packets that are no longer valid
+ */
+static void uhci_async_validate_end(UHCIState *s)
+{
+    UHCIAsync *curr = s->async_pending;
+    UHCIAsync **prev = &s->async_pending;
+    UHCIAsync *next;
+
+    while (curr) {
+        if (curr->valid > 0) {
+            prev = &curr->next;
+            curr = curr->next;
+            continue;
+        }
+
+        next = curr->next;
+
+        /* Unlink */
+        *prev = next;
+
+        uhci_async_cancel(s, curr);
+
+        curr = next;
+    }
+}
+
+static void uhci_async_cancel_all(UHCIState *s)
+{
+    UHCIAsync *curr = s->async_pending;
+    UHCIAsync *next;
+
+    while (curr) {
+        next = curr->next;
+
+        uhci_async_cancel(s, curr);
+
+        curr = next;
+    }
+
+    s->async_pending = NULL;
+}
+
+static UHCIAsync *uhci_async_find_td(UHCIState *s, uint32_t addr, uint32_t token)
+{
+    UHCIAsync *async = s->async_pending;
+    UHCIAsync *match = NULL;
+    int count = 0;
+
+    /*
+     * We're looking for the best match here. ie both td addr and token.
+     * Otherwise we return last good match. ie just token.
+     * It's ok to match just token because it identifies the transaction
+     * rather well, token includes: device addr, endpoint, size, etc.
+     *
+     * Also since we queue async transactions in reverse order by returning
+     * last good match we restores the order.
+     *
+     * It's expected that we wont have a ton of outstanding transactions.
+     * If we ever do we'd want to optimize this algorithm.
+     */
+
+    while (async) {
+        if (async->token == token) {
+            /* Good match */
+            match = async;
+
+            if (async->td == addr) {
+                /* Best match */
+                break;
+            }
+        }
+
+        async = async->next;
+        count++;
+    }
+
+    if (count > 64)
+	fprintf(stderr, "uhci: warning lots of async transactions\n");
+
+    return match;
+}
+
+static void uhci_attach(USBPort *port1, USBDevice *dev);
+
+static void uhci_update_irq(UHCIState *s)
+{
+    int level;
+    if (((s->status2 & 1) && (s->intr & (1 << 2))) ||
+        ((s->status2 & 2) && (s->intr & (1 << 3))) ||
+        ((s->status & UHCI_STS_USBERR) && (s->intr & (1 << 0))) ||
+        ((s->status & UHCI_STS_RD) && (s->intr & (1 << 1))) ||
+        (s->status & UHCI_STS_HSERR) ||
+        (s->status & UHCI_STS_HCPERR)) {
+        level = 1;
+    } else {
+        level = 0;
+    }
+    qemu_set_irq(s->dev.irq[3], level);
+}
+
+static void uhci_reset(UHCIState *s)
+{
+    uint8_t *pci_conf;
+    int i;
+    UHCIPort *port;
+
+    dprintf("uhci: full reset\n");
+
+    pci_conf = s->dev.config;
+
+    pci_conf[0x6a] = 0x01; /* usb clock */
+    pci_conf[0x6b] = 0x00;
+    s->cmd = 0;
+    s->status = 0;
+    s->status2 = 0;
+    s->intr = 0;
+    s->fl_base_addr = 0;
+    s->sof_timing = 64;
+
+    for(i = 0; i < NB_PORTS; i++) {
+        port = &s->ports[i];
+        port->ctrl = 0x0080;
+        if (port->port.dev)
+            uhci_attach(&port->port, port->port.dev);
+    }
+
+    uhci_async_cancel_all(s);
+}
+
+static void uhci_save(QEMUFile *f, void *opaque)
+{
+    UHCIState *s = opaque;
+    uint8_t num_ports = NB_PORTS;
+    int i;
+
+    uhci_async_cancel_all(s);
+
+    pci_device_save(&s->dev, f);
+
+    qemu_put_8s(f, &num_ports);
+    for (i = 0; i < num_ports; ++i)
+        qemu_put_be16s(f, &s->ports[i].ctrl);
+    qemu_put_be16s(f, &s->cmd);
+    qemu_put_be16s(f, &s->status);
+    qemu_put_be16s(f, &s->intr);
+    qemu_put_be16s(f, &s->frnum);
+    qemu_put_be32s(f, &s->fl_base_addr);
+    qemu_put_8s(f, &s->sof_timing);
+    qemu_put_8s(f, &s->status2);
+    qemu_put_timer(f, s->frame_timer);
+}
+
+static int uhci_load(QEMUFile *f, void *opaque, int version_id)
+{
+    UHCIState *s = opaque;
+    uint8_t num_ports;
+    int i, ret;
+
+    if (version_id > 1)
+        return -EINVAL;
+
+    ret = pci_device_load(&s->dev, f);
+    if (ret < 0)
+        return ret;
+
+    qemu_get_8s(f, &num_ports);
+    if (num_ports != NB_PORTS)
+        return -EINVAL;
+
+    for (i = 0; i < num_ports; ++i)
+        qemu_get_be16s(f, &s->ports[i].ctrl);
+    qemu_get_be16s(f, &s->cmd);
+    qemu_get_be16s(f, &s->status);
+    qemu_get_be16s(f, &s->intr);
+    qemu_get_be16s(f, &s->frnum);
+    qemu_get_be32s(f, &s->fl_base_addr);
+    qemu_get_8s(f, &s->sof_timing);
+    qemu_get_8s(f, &s->status2);
+    qemu_get_timer(f, s->frame_timer);
+
+    return 0;
+}
+
+static void uhci_ioport_writeb(void *opaque, uint32_t addr, uint32_t val)
+{
+    UHCIState *s = opaque;
+
+    addr &= 0x1f;
+    switch(addr) {
+    case 0x0c:
+        s->sof_timing = val;
+        break;
+    }
+}
+
+static uint32_t uhci_ioport_readb(void *opaque, uint32_t addr)
+{
+    UHCIState *s = opaque;
+    uint32_t val;
+
+    addr &= 0x1f;
+    switch(addr) {
+    case 0x0c:
+        val = s->sof_timing;
+        break;
+    default:
+        val = 0xff;
+        break;
+    }
+    return val;
+}
+
+static void uhci_ioport_writew(void *opaque, uint32_t addr, uint32_t val)
+{
+    UHCIState *s = opaque;
+
+    addr &= 0x1f;
+    dprintf("uhci: writew port=0x%04x val=0x%04x\n", addr, val);
+
+    switch(addr) {
+    case 0x00:
+        if ((val & UHCI_CMD_RS) && !(s->cmd & UHCI_CMD_RS)) {
+            /* start frame processing */
+            qemu_mod_timer(s->frame_timer, qemu_get_clock(vm_clock));
+            s->status &= ~UHCI_STS_HCHALTED;
+        } else if (!(val & UHCI_CMD_RS)) {
+            s->status |= UHCI_STS_HCHALTED;
+        }
+        if (val & UHCI_CMD_GRESET) {
+            UHCIPort *port;
+            USBDevice *dev;
+            int i;
+
+            /* send reset on the USB bus */
+            for(i = 0; i < NB_PORTS; i++) {
+                port = &s->ports[i];
+                dev = port->port.dev;
+                if (dev) {
+                    usb_send_msg(dev, USB_MSG_RESET);
+                }
+            }
+            uhci_reset(s);
+            return;
+        }
+        if (val & UHCI_CMD_HCRESET) {
+            uhci_reset(s);
+            return;
+        }
+        s->cmd = val;
+        break;
+    case 0x02:
+        s->status &= ~val;
+        /* XXX: the chip spec is not coherent, so we add a hidden
+           register to distinguish between IOC and SPD */
+        if (val & UHCI_STS_USBINT)
+            s->status2 = 0;
+        uhci_update_irq(s);
+        break;
+    case 0x04:
+        s->intr = val;
+        uhci_update_irq(s);
+        break;
+    case 0x06:
+        if (s->status & UHCI_STS_HCHALTED)
+            s->frnum = val & 0x7ff;
+        break;
+    case 0x10 ... 0x1f:
+        {
+            UHCIPort *port;
+            USBDevice *dev;
+            int n;
+
+            n = (addr >> 1) & 7;
+            if (n >= NB_PORTS)
+                return;
+            port = &s->ports[n];
+            dev = port->port.dev;
+            if (dev) {
+                /* port reset */
+                if ( (val & UHCI_PORT_RESET) &&
+                     !(port->ctrl & UHCI_PORT_RESET) ) {
+                    usb_send_msg(dev, USB_MSG_RESET);
+                }
+            }
+            port->ctrl = (port->ctrl & 0x01fb) | (val & ~0x01fb);
+            /* some bits are reset when a '1' is written to them */
+            port->ctrl &= ~(val & 0x000a);
+        }
+        break;
+    }
+}
+
+static uint32_t uhci_ioport_readw(void *opaque, uint32_t addr)
+{
+    UHCIState *s = opaque;
+    uint32_t val;
+
+    addr &= 0x1f;
+    switch(addr) {
+    case 0x00:
+        val = s->cmd;
+        break;
+    case 0x02:
+        val = s->status;
+        break;
+    case 0x04:
+        val = s->intr;
+        break;
+    case 0x06:
+        val = s->frnum;
+        break;
+    case 0x10 ... 0x1f:
+        {
+            UHCIPort *port;
+            int n;
+            n = (addr >> 1) & 7;
+            if (n >= NB_PORTS)
+                goto read_default;
+            port = &s->ports[n];
+            val = port->ctrl;
+        }
+        break;
+    default:
+    read_default:
+        val = 0xff7f; /* disabled port */
+        break;
+    }
+
+    dprintf("uhci: readw port=0x%04x val=0x%04x\n", addr, val);
+
+    return val;
+}
+
+static void uhci_ioport_writel(void *opaque, uint32_t addr, uint32_t val)
+{
+    UHCIState *s = opaque;
+
+    addr &= 0x1f;
+    dprintf("uhci: writel port=0x%04x val=0x%08x\n", addr, val);
+
+    switch(addr) {
+    case 0x08:
+        s->fl_base_addr = val & ~0xfff;
+        break;
+    }
+}
+
+static uint32_t uhci_ioport_readl(void *opaque, uint32_t addr)
+{
+    UHCIState *s = opaque;
+    uint32_t val;
+
+    addr &= 0x1f;
+    switch(addr) {
+    case 0x08:
+        val = s->fl_base_addr;
+        break;
+    default:
+        val = 0xffffffff;
+        break;
+    }
+    return val;
+}
+
+/* signal resume if controller suspended */
+static void uhci_resume (void *opaque)
+{
+    UHCIState *s = (UHCIState *)opaque;
+
+    if (!s)
+        return;
+
+    if (s->cmd & UHCI_CMD_EGSM) {
+        s->cmd |= UHCI_CMD_FGR;
+        s->status |= UHCI_STS_RD;
+        uhci_update_irq(s);
+    }
+}
+
+static void uhci_attach(USBPort *port1, USBDevice *dev)
+{
+    UHCIState *s = port1->opaque;
+    UHCIPort *port = &s->ports[port1->index];
+
+    if (dev) {
+        if (port->port.dev) {
+            usb_attach(port1, NULL);
+        }
+        /* set connect status */
+        port->ctrl |= UHCI_PORT_CCS | UHCI_PORT_CSC;
+
+        /* update speed */
+        if (dev->speed == USB_SPEED_LOW)
+            port->ctrl |= UHCI_PORT_LSDA;
+        else
+            port->ctrl &= ~UHCI_PORT_LSDA;
+
+        uhci_resume(s);
+
+        port->port.dev = dev;
+        /* send the attach message */
+        usb_send_msg(dev, USB_MSG_ATTACH);
+    } else {
+        /* set connect status */
+        if (port->ctrl & UHCI_PORT_CCS) {
+            port->ctrl &= ~UHCI_PORT_CCS;
+            port->ctrl |= UHCI_PORT_CSC;
+        }
+        /* disable port */
+        if (port->ctrl & UHCI_PORT_EN) {
+            port->ctrl &= ~UHCI_PORT_EN;
+            port->ctrl |= UHCI_PORT_ENC;
+        }
+
+        uhci_resume(s);
+
+        dev = port->port.dev;
+        if (dev) {
+            /* send the detach message */
+            usb_send_msg(dev, USB_MSG_DETACH);
+        }
+        port->port.dev = NULL;
+    }
+}
+
+static int uhci_broadcast_packet(UHCIState *s, USBPacket *p)
+{
+    int i, ret;
+
+    dprintf("uhci: packet enter. pid %s addr 0x%02x ep %d len %d\n",
+           pid2str(p->pid), p->devaddr, p->devep, p->len);
+    if (p->pid == USB_TOKEN_OUT || p->pid == USB_TOKEN_SETUP)
+        dump_data(p->data, p->len);
+
+    ret = USB_RET_NODEV;
+    for (i = 0; i < NB_PORTS && ret == USB_RET_NODEV; i++) {
+        UHCIPort *port = &s->ports[i];
+        USBDevice *dev = port->port.dev;
+
+        if (dev && (port->ctrl & UHCI_PORT_EN))
+            ret = dev->handle_packet(dev, p);
+    }
+
+    dprintf("uhci: packet exit. ret %d len %d\n", ret, p->len);
+    if (p->pid == USB_TOKEN_IN && ret > 0)
+        dump_data(p->data, ret);
+
+    return ret;
+}
+
+static void uhci_async_complete(USBPacket * packet, void *opaque);
+static void uhci_process_frame(UHCIState *s);
+
+/* return -1 if fatal error (frame must be stopped)
+          0 if TD successful
+          1 if TD unsuccessful or inactive
+*/
+static int uhci_complete_td(UHCIState *s, UHCI_TD *td, UHCIAsync *async, uint32_t *int_mask)
+{
+    int len = 0, max_len, err, ret;
+    uint8_t pid;
+
+    max_len = ((td->token >> 21) + 1) & 0x7ff;
+    pid = td->token & 0xff;
+
+    ret = async->packet.len;
+
+    if (td->ctrl & TD_CTRL_IOC)
+        *int_mask |= 0x01;
+
+    if (td->ctrl & TD_CTRL_IOS)
+        td->ctrl &= ~TD_CTRL_ACTIVE;
+
+    if (ret < 0)
+        goto out;
+
+    len = async->packet.len;
+    td->ctrl = (td->ctrl & ~0x7ff) | ((len - 1) & 0x7ff);
+
+    /* The NAK bit may have been set by a previous frame, so clear it
+       here.  The docs are somewhat unclear, but win2k relies on this
+       behavior.  */
+    td->ctrl &= ~(TD_CTRL_ACTIVE | TD_CTRL_NAK);
+
+    if (pid == USB_TOKEN_IN) {
+        if (len > max_len) {
+            len = max_len;
+            ret = USB_RET_BABBLE;
+            goto out;
+        }
+
+        if (len > 0) {
+            /* write the data back */
+            cpu_physical_memory_write(td->buffer, async->buffer, len);
+        }
+
+        if ((td->ctrl & TD_CTRL_SPD) && len < max_len) {
+            *int_mask |= 0x02;
+            /* short packet: do not update QH */
+            dprintf("uhci: short packet. td 0x%x token 0x%x\n", async->td, async->token);
+            return 1;
+        }
+    }
+
+    /* success */
+    return 0;
+
+out:
+    switch(ret) {
+    case USB_RET_STALL:
+        td->ctrl |= TD_CTRL_STALL;
+        td->ctrl &= ~TD_CTRL_ACTIVE;
+        return 1;
+
+    case USB_RET_BABBLE:
+        td->ctrl |= TD_CTRL_BABBLE | TD_CTRL_STALL;
+        td->ctrl &= ~TD_CTRL_ACTIVE;
+        /* frame interrupted */
+        return -1;
+
+    case USB_RET_NAK:
+        td->ctrl |= TD_CTRL_NAK;
+        if (pid == USB_TOKEN_SETUP)
+            break;
+	return 1;
+
+    case USB_RET_NODEV:
+    default:
+	break;
+    }
+
+    /* Retry the TD if error count is not zero */
+
+    td->ctrl |= TD_CTRL_TIMEOUT;
+    err = (td->ctrl >> TD_CTRL_ERROR_SHIFT) & 3;
+    if (err != 0) {
+        err--;
+        if (err == 0) {
+            td->ctrl &= ~TD_CTRL_ACTIVE;
+            s->status |= UHCI_STS_USBERR;
+            uhci_update_irq(s);
+        }
+    }
+    td->ctrl = (td->ctrl & ~(3 << TD_CTRL_ERROR_SHIFT)) |
+        (err << TD_CTRL_ERROR_SHIFT);
+    return 1;
+}
+
+static int uhci_handle_td(UHCIState *s, uint32_t addr, UHCI_TD *td, uint32_t *int_mask)
+{
+    UHCIAsync *async;
+    int len = 0, max_len;
+    uint8_t pid;
+
+    /* Is active ? */
+    if (!(td->ctrl & TD_CTRL_ACTIVE))
+        return 1;
+
+    async = uhci_async_find_td(s, addr, td->token);
+    if (async) {
+        /* Already submitted */
+        async->valid = 32;
+
+        if (!async->done)
+            return 1;
+
+        uhci_async_unlink(s, async);
+        goto done;
+    }
+
+    /* Allocate new packet */
+    async = uhci_async_alloc(s);
+    if (!async)
+        return 1;
+
+    async->valid = 10;
+    async->td    = addr;
+    async->token = td->token;
+
+    max_len = ((td->token >> 21) + 1) & 0x7ff;
+    pid = td->token & 0xff;
+
+    async->packet.pid     = pid;
+    async->packet.devaddr = (td->token >> 8) & 0x7f;
+    async->packet.devep   = (td->token >> 15) & 0xf;
+    async->packet.data    = async->buffer;
+    async->packet.len     = max_len;
+    async->packet.complete_cb     = uhci_async_complete;
+    async->packet.complete_opaque = s;
+
+    switch(pid) {
+    case USB_TOKEN_OUT:
+    case USB_TOKEN_SETUP:
+        cpu_physical_memory_read(td->buffer, async->buffer, max_len);
+        len = uhci_broadcast_packet(s, &async->packet);
+        if (len >= 0)
+            len = max_len;
+        break;
+
+    case USB_TOKEN_IN:
+        len = uhci_broadcast_packet(s, &async->packet);
+        break;
+
+    default:
+        /* invalid pid : frame interrupted */
+        uhci_async_free(s, async);
+        s->status |= UHCI_STS_HCPERR;
+        uhci_update_irq(s);
+        return -1;
+    }
+ 
+    if (len == USB_RET_ASYNC) {
+        uhci_async_link(s, async);
+        return 2;
+    }
+
+    async->packet.len = len;
+
+done:
+    len = uhci_complete_td(s, td, async, int_mask);
+    uhci_async_free(s, async);
+    return len;
+}
+
+static void uhci_async_complete(USBPacket *packet, void *opaque)
+{
+    UHCIState *s = opaque;
+    UHCIAsync *async = (UHCIAsync *) packet;
+
+    dprintf("uhci: async complete. td 0x%x token 0x%x\n", async->td, async->token);
+
+    async->done = 1;
+
+    uhci_process_frame(s);
+}
+
+static int is_valid(uint32_t link)
+{
+    return (link & 1) == 0;
+}
+
+static int is_qh(uint32_t link)
+{
+    return (link & 2) != 0;
+}
+
+static int depth_first(uint32_t link)
+{
+    return (link & 4) != 0;
+}
+
+/* QH DB used for detecting QH loops */
+#define UHCI_MAX_QUEUES 128
+typedef struct {
+    uint32_t addr[UHCI_MAX_QUEUES];
+    int      count;
+} QhDb;
+
+static void qhdb_reset(QhDb *db)
+{
+    db->count = 0;
+}
+
+/* Add QH to DB. Returns 1 if already present or DB is full. */
+static int qhdb_insert(QhDb *db, uint32_t addr)
+{
+    int i;
+    for (i = 0; i < db->count; i++)
+        if (db->addr[i] == addr)
+            return 1;
+
+    if (db->count >= UHCI_MAX_QUEUES)
+        return 1;
+
+    db->addr[db->count++] = addr;
+    return 0;
+}
+
+static void uhci_process_frame(UHCIState *s)
+{
+    uint32_t frame_addr, link, old_td_ctrl, val, int_mask;
+    uint32_t curr_qh;
+    int cnt, ret;
+    UHCI_TD td;
+    UHCI_QH qh;
+    QhDb qhdb;
+
+    frame_addr = s->fl_base_addr + ((s->frnum & 0x3ff) << 2);
+
+    dprintf("uhci: processing frame %d addr 0x%x\n" , s->frnum, frame_addr);
+
+    cpu_physical_memory_read(frame_addr, (uint8_t *)&link, 4);
+    le32_to_cpus(&link);
+
+    int_mask = 0;
+    curr_qh  = 0;
+
+    qhdb_reset(&qhdb);
+
+    for (cnt = FRAME_MAX_LOOPS; is_valid(link) && cnt; cnt--) {
+        if (is_qh(link)) {
+            /* QH */
+
+            if (qhdb_insert(&qhdb, link)) {
+                /*
+                 * We're going in circles. Which is not a bug because
+                 * HCD is allowed to do that as part of the BW management. 
+                 * In our case though it makes no sense to spin here. Sync transations 
+                 * are already done, and async completion handler will re-process 
+                 * the frame when something is ready.
+                 */
+                dprintf("uhci: detected loop. qh 0x%x\n", link);
+                break;
+            }
+
+            cpu_physical_memory_read(link & ~0xf, (uint8_t *) &qh, sizeof(qh));
+            le32_to_cpus(&qh.link);
+            le32_to_cpus(&qh.el_link);
+
+            dprintf("uhci: QH 0x%x load. link 0x%x elink 0x%x\n",
+                    link, qh.link, qh.el_link);
+
+            if (!is_valid(qh.el_link)) {
+                /* QH w/o elements */
+                curr_qh = 0;
+                link = qh.link;
+            } else {
+                /* QH with elements */
+            	curr_qh = link;
+            	link = qh.el_link;
+            }
+            continue;
+        }
+
+        /* TD */
+        cpu_physical_memory_read(link & ~0xf, (uint8_t *) &td, sizeof(td));
+        le32_to_cpus(&td.link);
+        le32_to_cpus(&td.ctrl);
+        le32_to_cpus(&td.token);
+        le32_to_cpus(&td.buffer);
+
+        dprintf("uhci: TD 0x%x load. link 0x%x ctrl 0x%x token 0x%x qh 0x%x\n", 
+                link, td.link, td.ctrl, td.token, curr_qh);
+
+        old_td_ctrl = td.ctrl;
+        ret = uhci_handle_td(s, link, &td, &int_mask);
+        if (old_td_ctrl != td.ctrl) {
+            /* update the status bits of the TD */
+            val = cpu_to_le32(td.ctrl);
+            cpu_physical_memory_write((link & ~0xf) + 4,
+                                      (const uint8_t *)&val, sizeof(val));
+        }
+
+        if (ret < 0) {
+            /* interrupted frame */
+            break;
+        }
+
+        if (ret == 2 || ret == 1) {
+            dprintf("uhci: TD 0x%x %s. link 0x%x ctrl 0x%x token 0x%x qh 0x%x\n",
+                    link, ret == 2 ? "pend" : "skip",
+                    td.link, td.ctrl, td.token, curr_qh);
+
+            link = curr_qh ? qh.link : td.link;
+            continue;
+        }
+
+        /* completed TD */
+
+        dprintf("uhci: TD 0x%x done. link 0x%x ctrl 0x%x token 0x%x qh 0x%x\n", 
+                link, td.link, td.ctrl, td.token, curr_qh);
+
+        link = td.link;
+
+        if (curr_qh) {
+	    /* update QH element link */
+            qh.el_link = link;
+            val = cpu_to_le32(qh.el_link);
+            cpu_physical_memory_write((curr_qh & ~0xf) + 4,
+                                          (const uint8_t *)&val, sizeof(val));
+
+            if (!depth_first(link)) {
+               /* done with this QH */
+
+               dprintf("uhci: QH 0x%x done. link 0x%x elink 0x%x\n",
+                       curr_qh, qh.link, qh.el_link);
+
+               curr_qh = 0;
+               link    = qh.link;
+            }
+        }
+
+        /* go to the next entry */
+    }
+
+    s->pending_int_mask = int_mask;
+}
+
+static void uhci_frame_timer(void *opaque)
+{
+    UHCIState *s = opaque;
+    int64_t expire_time;
+
+    if (!(s->cmd & UHCI_CMD_RS)) {
+        /* Full stop */
+        qemu_del_timer(s->frame_timer);
+        /* set hchalted bit in status - UHCI11D 2.1.2 */
+        s->status |= UHCI_STS_HCHALTED;
+
+        dprintf("uhci: halted\n");
+        return;
+    }
+
+    /* Complete the previous frame */
+    if (s->pending_int_mask) {
+        s->status2 |= s->pending_int_mask;
+        s->status  |= UHCI_STS_USBINT;
+        uhci_update_irq(s);
+    }
+
+    /* Start new frame */
+    s->frnum = (s->frnum + 1) & 0x7ff;
+
+    dprintf("uhci: new frame #%u\n" , s->frnum);
+
+    uhci_async_validate_begin(s);
+
+    uhci_process_frame(s);
+
+    uhci_async_validate_end(s);
+
+    /* prepare the timer for the next frame */
+    expire_time = qemu_get_clock(vm_clock) +
+        (ticks_per_sec / FRAME_TIMER_FREQ);
+    qemu_mod_timer(s->frame_timer, expire_time);
+}
+
+static void uhci_map(PCIDevice *pci_dev, int region_num,
+                    uint32_t addr, uint32_t size, int type)
+{
+    UHCIState *s = (UHCIState *)pci_dev;
+
+    register_ioport_write(addr, 32, 2, uhci_ioport_writew, s);
+    register_ioport_read(addr, 32, 2, uhci_ioport_readw, s);
+    register_ioport_write(addr, 32, 4, uhci_ioport_writel, s);
+    register_ioport_read(addr, 32, 4, uhci_ioport_readl, s);
+    register_ioport_write(addr, 32, 1, uhci_ioport_writeb, s);
+    register_ioport_read(addr, 32, 1, uhci_ioport_readb, s);
+}
+
+void usb_uhci_piix3_init(PCIBus *bus, int devfn)
+{
+    UHCIState *s;
+    uint8_t *pci_conf;
+    int i;
+
+    s = (UHCIState *)pci_register_device(bus,
+                                        "USB-UHCI", sizeof(UHCIState),
+                                        devfn, NULL, NULL);
+    pci_conf = s->dev.config;
+    pci_conf[0x00] = 0x86;
+    pci_conf[0x01] = 0x80;
+    pci_conf[0x02] = 0x20;
+    pci_conf[0x03] = 0x70;
+    pci_conf[0x08] = 0x01; // revision number
+    pci_conf[0x09] = 0x00;
+    pci_conf[0x0a] = 0x03;
+    pci_conf[0x0b] = 0x0c;
+    pci_conf[0x0e] = 0x00; // header_type
+    pci_conf[0x3d] = 4; // interrupt pin 3
+    pci_conf[0x60] = 0x10; // release number
+
+    for(i = 0; i < NB_PORTS; i++) {
+        qemu_register_usb_port(&s->ports[i].port, s, i, uhci_attach);
+    }
+    s->frame_timer = qemu_new_timer(vm_clock, uhci_frame_timer, s);
+
+    uhci_reset(s);
+
+    /* Use region 4 for consistency with real hardware.  BSD guests seem
+       to rely on this.  */
+    pci_register_io_region(&s->dev, 4, 0x20,
+                           PCI_ADDRESS_SPACE_IO, uhci_map);
+
+    register_savevm("uhci", 0, 1, uhci_save, uhci_load, s);
+}
+
+void usb_uhci_piix4_init(PCIBus *bus, int devfn)
+{
+    UHCIState *s;
+    uint8_t *pci_conf;
+    int i;
+
+    s = (UHCIState *)pci_register_device(bus,
+                                        "USB-UHCI", sizeof(UHCIState),
+                                        devfn, NULL, NULL);
+    pci_conf = s->dev.config;
+    pci_conf[0x00] = 0x86;
+    pci_conf[0x01] = 0x80;
+    pci_conf[0x02] = 0x12;
+    pci_conf[0x03] = 0x71;
+    pci_conf[0x08] = 0x01; // revision number
+    pci_conf[0x09] = 0x00;
+    pci_conf[0x0a] = 0x03;
+    pci_conf[0x0b] = 0x0c;
+    pci_conf[0x0e] = 0x00; // header_type
+    pci_conf[0x3d] = 4; // interrupt pin 3
+    pci_conf[0x60] = 0x10; // release number
+
+    for(i = 0; i < NB_PORTS; i++) {
+        qemu_register_usb_port(&s->ports[i].port, s, i, uhci_attach);
+    }
+    s->frame_timer = qemu_new_timer(vm_clock, uhci_frame_timer, s);
+
+    uhci_reset(s);
+
+    /* Use region 4 for consistency with real hardware.  BSD guests seem
+       to rely on this.  */
+    pci_register_io_region(&s->dev, 4, 0x20,
+                           PCI_ADDRESS_SPACE_IO, uhci_map);
+
+    register_savevm("uhci", 0, 1, uhci_save, uhci_load, s);
+}