source: mainline/uspace/drv/bus/usb/xhci/rh.c@ e0a5d4c

/*
 * Copyright (c) 2018 Petr Manek, Ondrej Hlavaty, Michal Staruch, Jaroslav Jindrak
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup drvusbxhci
 * @{
 */
/** @file
 * @brief The roothub structures abstraction.
 */

#include <errno.h>
#include <str_error.h>
#include <usb/request.h>
#include <usb/debug.h>
#include <usb/host/bus.h>
#include <usb/host/ddf_helpers.h>
#include <usb/dma_buffer.h>
#include <usb/host/hcd.h>
#include <usb/port.h>

#include "debug.h"
#include "commands.h"
#include "endpoint.h"
#include "hc.h"
#include "hw_struct/trb.h"
#include "rh.h"
#include "transfers.h"

/* This mask only lists registers, which imply port change. */
static const uint32_t port_events_mask =
        XHCI_REG_MASK(XHCI_PORT_CSC) |
        XHCI_REG_MASK(XHCI_PORT_PEC) |
        XHCI_REG_MASK(XHCI_PORT_WRC) |
        XHCI_REG_MASK(XHCI_PORT_OCC) |
        XHCI_REG_MASK(XHCI_PORT_PRC) |
        XHCI_REG_MASK(XHCI_PORT_PLC) |
        XHCI_REG_MASK(XHCI_PORT_CEC);

static const uint32_t port_reset_mask =
        XHCI_REG_MASK(XHCI_PORT_WRC) |
        XHCI_REG_MASK(XHCI_PORT_PRC);

typedef struct rh_port {
        usb_port_t base;
        xhci_rh_t *rh;
        uint8_t major;
        xhci_port_regs_t *regs;
        xhci_device_t *device;
} rh_port_t;

static int rh_worker(void *);

/**
 * Initialize the roothub subsystem.
 */
errno_t xhci_rh_init(xhci_rh_t *rh, xhci_hc_t *hc)
{
        assert(rh);
        assert(hc);

        rh->hc = hc;
        rh->max_ports = XHCI_REG_RD(hc->cap_regs, XHCI_CAP_MAX_PORTS);
        rh->ports = calloc(rh->max_ports, sizeof(rh_port_t));
        if (!rh->ports)
                return ENOMEM;

        const errno_t err = bus_device_init(&rh->device.base, &rh->hc->bus.base);
        if (err) {
                free(rh->ports);
                return err;
        }

        rh->event_worker = joinable_fibril_create(&rh_worker, rh);
        if (!rh->event_worker) {
                free(rh->ports);
                return err;
        }

        for (unsigned i = 0; i < rh->max_ports; i++) {
                usb_port_init(&rh->ports[i].base);
                rh->ports[i].rh = rh;
                rh->ports[i].regs = &rh->hc->op_regs->portrs[i];
        }

        /* Initialize route string */
        rh->device.route_str = 0;

        xhci_sw_ring_init(&rh->event_ring, rh->max_ports);

        return EOK;
}

/**
 * Finalize the RH subsystem.
 */
errno_t xhci_rh_fini(xhci_rh_t *rh)
{
        assert(rh);
        xhci_rh_stop(rh);

        joinable_fibril_destroy(rh->event_worker);
        xhci_sw_ring_fini(&rh->event_ring);
        return EOK;
}

static rh_port_t *get_rh_port(usb_port_t *port)
{
        assert(port);
        return (rh_port_t *) port;
}

/**
 * Create and setup a device directly connected to RH. As the xHCI is not using
 * a virtual usbhub device for RH, this routine is called for devices directly.
 */
static errno_t rh_enumerate_device(usb_port_t *usb_port)
{
        errno_t err;
        rh_port_t *port = get_rh_port(usb_port);

        if (port->major <= 2) {
                /* USB ports for lower speeds needs their port reset first. */
                XHCI_REG_SET(port->regs, XHCI_PORT_PR, 1);
                if ((err = usb_port_wait_for_enabled(&port->base)))
                        return err;
        } else {
                /* Do the Warm reset to ensure the state is clear. */
                XHCI_REG_SET(port->regs, XHCI_PORT_WPR, 1);
                if ((err = usb_port_wait_for_enabled(&port->base)))
                        return err;
        }

        /*
         * We cannot know in advance, whether the speed in the status register
         * is valid - it depends on the protocol. So we read it later, but then
         * we have to check if the port is still enabled.
         */
        uint32_t status = XHCI_REG_RD_FIELD(&port->regs->portsc, 32);

        bool enabled = !!(status & XHCI_REG_MASK(XHCI_PORT_PED));
        if (!enabled)
                return ENOENT;

        unsigned psiv = (status & XHCI_REG_MASK(XHCI_PORT_PS))
            >> XHCI_REG_SHIFT(XHCI_PORT_PS);
        const usb_speed_t speed = port->rh->hc->speeds[psiv].usb_speed;

        device_t *dev = hcd_ddf_fun_create(&port->rh->hc->base, speed);
        if (!dev) {
                usb_log_error("Failed to create USB device function.");
                return ENOMEM;
        }

        dev->hub = &port->rh->device.base;
        dev->tier = 1;
        dev->port = port - port->rh->ports + 1;

        port->device = xhci_device_get(dev);
        port->device->rh_port = dev->port;

        usb_log_debug("Enumerating new %s-speed device on port %u.",
            usb_str_speed(dev->speed), dev->port);

        if ((err = bus_device_enumerate(dev))) {
                usb_log_error("Failed to enumerate USB device: %s", str_error(err));
                return err;
        }

        if (!ddf_fun_get_name(dev->fun)) {
                bus_device_set_default_name(dev);
        }

        if ((err = ddf_fun_bind(dev->fun))) {
                usb_log_error("Failed to register device " XHCI_DEV_FMT " DDF function: %s.",
                    XHCI_DEV_ARGS(*port->device), str_error(err));
                goto err_usb_dev;
        }

        return EOK;

err_usb_dev:
        hcd_ddf_fun_destroy(dev);
        port->device = NULL;
        return err;
}

/**
 * Deal with a detached device.
 */
static void rh_remove_device(usb_port_t *usb_port)
{
        rh_port_t *port = get_rh_port(usb_port);

        assert(port->device);
        usb_log_info("Device " XHCI_DEV_FMT " at port %zu has been disconnected.",
            XHCI_DEV_ARGS(*port->device), port - port->rh->ports + 1);

        /* Remove device from XHCI bus. */
        bus_device_gone(&port->device->base);

        /* Mark the device as detached. */
        port->device = NULL;
}

/**
 * Handle all changes on specified port.
 */
static void handle_port_change(xhci_rh_t *rh, uint8_t port_id)
{
        rh_port_t * const port = &rh->ports[port_id - 1];

        uint32_t status = XHCI_REG_RD_FIELD(&port->regs->portsc, 32);

        while (status & port_events_mask) {
                /*
                 * 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.
                 */
                XHCI_REG_WR_FIELD(&port->regs->portsc,
                    status & ~XHCI_REG_MASK(XHCI_PORT_PED), 32);

                const bool connected = !!(status & XHCI_REG_MASK(XHCI_PORT_CCS));
                const bool enabled = !!(status & XHCI_REG_MASK(XHCI_PORT_PED));

                if (status & XHCI_REG_MASK(XHCI_PORT_CSC)) {
                        usb_log_info("Connected state changed on port %u.", port_id);
                        status &= ~XHCI_REG_MASK(XHCI_PORT_CSC);

                        if (connected) {
                                usb_port_connected(&port->base, &rh_enumerate_device);
                        } else {
                                usb_port_disabled(&port->base, &rh_remove_device);
                        }
                }

                if (status & port_reset_mask) {
                        status &= ~port_reset_mask;

                        if (enabled) {
                                usb_port_enabled(&port->base);
                        } else {
                                usb_port_disabled(&port->base, &rh_remove_device);
                        }
                }

                status &= port_events_mask;
                if (status != 0)
                        usb_log_debug("RH port %u change not handled: 0x%x", port_id, status);
                
                /* Make sure that PSCEG is 0 before exiting the loop. */
                status = XHCI_REG_RD_FIELD(&port->regs->portsc, 32);
        }
}

void xhci_rh_set_ports_protocol(xhci_rh_t *rh,
        unsigned offset, unsigned count, unsigned major)
{
        for (unsigned i = offset; i < offset + count; i++)
                rh->ports[i - 1].major = major;
}

void xhci_rh_start(xhci_rh_t *rh)
{
        xhci_sw_ring_restart(&rh->event_ring);
        joinable_fibril_start(rh->event_worker);

        /* The reset changed status of all ports, and SW originated reason does
         * not cause an interrupt.
         */
        for (uint8_t i = 0; i < rh->max_ports; ++i) {
                handle_port_change(rh, i + 1);

                rh_port_t * const port = &rh->ports[i];

                /*
                 * When xHCI starts, for some reasons USB 3 ports do not have
                 * the CSC bit, even though they are connected. Try to find
                 * such ports.
                 */
                if (XHCI_REG_RD(port->regs, XHCI_PORT_CCS)
                    && port->base.state == PORT_DISABLED)
                        usb_port_connected(&port->base, &rh_enumerate_device);
        }
}

/**
 * Disconnect all devices on all ports. On contrary to ordinary disconnect, this
 * function waits until the disconnection routine is over.
 */
void xhci_rh_stop(xhci_rh_t *rh)
{
        xhci_sw_ring_stop(&rh->event_ring);
        joinable_fibril_join(rh->event_worker);

        for (uint8_t i = 0; i < rh->max_ports; ++i) {
                rh_port_t * const port = &rh->ports[i];
                usb_port_disabled(&port->base, &rh_remove_device);
                usb_port_fini(&port->base);
        }
}

static int rh_worker(void *arg)
{
        xhci_rh_t * const rh = arg;

        xhci_trb_t trb;
        while (xhci_sw_ring_dequeue(&rh->event_ring, &trb) == EOK) {
                uint8_t port_id = XHCI_QWORD_EXTRACT(trb.parameter, 31, 24);
                usb_log_debug("Port status change event detected for port %u.", port_id);
                handle_port_change(rh, port_id);
        }

        return 0;
}

/**
 * @}
 */