freebsd-dev/sys/dev/usb/usb_bus.h
Hans Petter Selasky 43ea03d756 Improve the realtime properties of USB transfers for embedded systems
like RPI-B and RPI-2.

Description of problem:
USB transfers can process data in their callbacks sometimes causing
unacceptable latency for other USB transfers. Separate BULK completion
callbacks from CONTROL, INTERRUPT and ISOCHRONOUS callbacks, and give
BULK completion callbacks lesser execution priority than the
others. This way USB audio won't be interfered by heavy USB ethernet
usage for example.

Further serve USB transfer completion in a round robin fashion,
instead of only serving the most CPU hungry. This has been done by
adding a third flag to USB transfer queue structure which keeps track
of looping callbacks. The "command" callback function then decides
what to do when looping.

MFC after:		2 weeks
2015-08-14 12:57:53 +00:00

135 lines
4.5 KiB
C

/* $FreeBSD$ */
/*-
* Copyright (c) 2008 Hans Petter Selasky. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
*/
#ifndef _USB_BUS_H_
#define _USB_BUS_H_
struct usb_fs_privdata;
/*
* The following structure defines the USB explore message sent to the USB
* explore process.
*/
struct usb_bus_msg {
struct usb_proc_msg hdr;
struct usb_bus *bus;
};
/*
* The following structure defines the USB statistics structure.
*/
struct usb_bus_stat {
uint32_t uds_requests[4];
};
/*
* The following structure defines an USB BUS. There is one USB BUS
* for every Host or Device controller.
*/
struct usb_bus {
struct usb_bus_stat stats_err;
struct usb_bus_stat stats_ok;
#if USB_HAVE_ROOT_MOUNT_HOLD
struct root_hold_token *bus_roothold;
#endif
/* convenience macros */
#define USB_BUS_TT_PROC(bus) USB_BUS_NON_GIANT_ISOC_PROC(bus)
#define USB_BUS_CS_PROC(bus) USB_BUS_NON_GIANT_ISOC_PROC(bus)
#if USB_HAVE_PER_BUS_PROCESS
#define USB_BUS_GIANT_PROC(bus) (&(bus)->giant_callback_proc)
#define USB_BUS_NON_GIANT_ISOC_PROC(bus) (&(bus)->non_giant_isoc_callback_proc)
#define USB_BUS_NON_GIANT_BULK_PROC(bus) (&(bus)->non_giant_bulk_callback_proc)
#define USB_BUS_EXPLORE_PROC(bus) (&(bus)->explore_proc)
#define USB_BUS_CONTROL_XFER_PROC(bus) (&(bus)->control_xfer_proc)
/*
* There are three callback processes. One for Giant locked
* callbacks. One for non-Giant locked non-periodic callbacks
* and one for non-Giant locked periodic callbacks. This
* should avoid congestion and reduce response time in most
* cases.
*/
struct usb_process giant_callback_proc;
struct usb_process non_giant_isoc_callback_proc;
struct usb_process non_giant_bulk_callback_proc;
/* Explore process */
struct usb_process explore_proc;
/* Control request process */
struct usb_process control_xfer_proc;
#endif
struct usb_bus_msg explore_msg[2];
struct usb_bus_msg detach_msg[2];
struct usb_bus_msg attach_msg[2];
struct usb_bus_msg suspend_msg[2];
struct usb_bus_msg resume_msg[2];
struct usb_bus_msg reset_msg[2];
struct usb_bus_msg shutdown_msg[2];
#if USB_HAVE_UGEN
struct usb_bus_msg cleanup_msg[2];
LIST_HEAD(,usb_fs_privdata) pd_cleanup_list;
#endif
/*
* This mutex protects the USB hardware:
*/
struct mtx bus_mtx;
struct mtx bus_spin_lock;
struct usb_xfer_queue intr_q;
struct usb_callout power_wdog; /* power management */
device_t parent;
device_t bdev; /* filled by HC driver */
#if USB_HAVE_BUSDMA
struct usb_dma_parent_tag dma_parent_tag[1];
struct usb_dma_tag dma_tags[USB_BUS_DMA_TAG_MAX];
#endif
const struct usb_bus_methods *methods; /* filled by HC driver */
struct usb_device **devices;
struct ifnet *ifp; /* only for USB Packet Filter */
usb_power_mask_t hw_power_state; /* see USB_HW_POWER_XXX */
usb_size_t uframe_usage[USB_HS_MICRO_FRAMES_MAX];
uint16_t isoc_time_last; /* in milliseconds */
uint8_t alloc_failed; /* Set if memory allocation failed. */
uint8_t driver_added_refcount; /* Current driver generation count */
enum usb_revision usbrev; /* USB revision. See "USB_REV_XXX". */
uint8_t devices_max; /* maximum number of USB devices */
uint8_t do_probe; /* set if USB should be re-probed */
uint8_t no_explore; /* don't explore USB ports */
uint8_t dma_bits; /* number of DMA address lines */
};
#endif /* _USB_BUS_H_ */