Date: Wed, 2 Apr 2014 01:58:54 +0000 (UTC) From: Ian Lepore <ian@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r264031 - head/sys/dev/usb/serial Message-ID: <201404020158.s321wsB0002050@svn.freebsd.org>
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Author: ian Date: Wed Apr 2 01:58:54 2014 New Revision: 264031 URL: http://svnweb.freebsd.org/changeset/base/264031 Log: Use 2K buffers for IO to help achieve full device speed, rather than the default wMaxPacketSize (64 or 512 bytes). This actually helps older FTDI devices (which were USB 1/full speed) more than the new H-series high speed, but even for the new chips it helps cut the number of interrupts when doing very high speed (3-12mbaud). Modified: head/sys/dev/usb/serial/uftdi.c Modified: head/sys/dev/usb/serial/uftdi.c ============================================================================== --- head/sys/dev/usb/serial/uftdi.c Tue Apr 1 22:54:54 2014 (r264030) +++ head/sys/dev/usb/serial/uftdi.c Wed Apr 2 01:58:54 2014 (r264031) @@ -63,6 +63,7 @@ __FBSDID("$FreeBSD$"); #include <dev/usb/usb.h> #include <dev/usb/usbdi.h> #include <dev/usb/usbdi_util.h> +#include <dev/usb/usb_core.h> #include "usbdevs.h" #define USB_DEBUG_VAR uftdi_debug @@ -83,8 +84,34 @@ SYSCTL_INT(_hw_usb_uftdi, OID_AUTO, debu #define UFTDI_CONFIG_INDEX 0 #define UFTDI_IFACE_INDEX_JTAG 0 -#define UFTDI_OBUFSIZE 64 /* bytes, cannot be increased due to - * do size encoding */ +/* + * IO buffer sizes and FTDI device procotol sizes. + * + * Note that the output packet size in the following defines is not the usb + * protocol packet size based on bus speed, it is the size dictated by the FTDI + * device itself, and is used only on older chips. + * + * We allocate buffers bigger than the hardware's packet size, and process + * multiple packets within each buffer. This allows the controller to make + * optimal use of the usb bus by conducting multiple transfers with the device + * during a single bus timeslice to fill or drain the chip's fifos. + * + * The output data on newer chips has no packet header, and we are able to pack + * any number of output bytes into a buffer. On some older chips, each output + * packet contains a 1-byte header and up to 63 bytes of payload. The size is + * encoded in 6 bits of the header, hence the 64-byte limit on packet size. We + * loop to fill the buffer with many of these header+payload packets. + * + * The input data on all chips consists of packets which contain a 2-byte header + * followed by data payload. The total size of the packet is wMaxPacketSize + * which can change based on the bus speed (e.g., 64 for full speed, 512 for + * high speed). We loop to extract the headers and payloads from the packets + * packed into an input buffer. + */ +#define UFTDI_IBUFSIZE 2048 +#define UFTDI_IHDRSIZE 2 +#define UFTDI_OBUFSIZE 2048 +#define UFTDI_OPKTSIZE 64 enum { UFTDI_BULK_DT_WR, @@ -178,7 +205,7 @@ static const struct usb_config uftdi_con .type = UE_BULK, .endpoint = UE_ADDR_ANY, .direction = UE_DIR_IN, - .bufsize = 0, /* use wMaxPacketSize */ + .bufsize = UFTDI_IBUFSIZE, .flags = {.pipe_bof = 1,.short_xfer_ok = 1,}, .callback = &uftdi_read_callback, }, @@ -1096,35 +1123,47 @@ uftdi_write_callback(struct usb_xfer *xf { struct uftdi_softc *sc = usbd_xfer_softc(xfer); struct usb_page_cache *pc; - uint32_t actlen; + uint32_t pktlen; + uint32_t buflen; uint8_t buf[1]; switch (USB_GET_STATE(xfer)) { + default: /* Error */ + if (error != USB_ERR_CANCELLED) { + /* try to clear stall first */ + usbd_xfer_set_stall(xfer); + } + /* FALLTHROUGH */ case USB_ST_SETUP: case USB_ST_TRANSFERRED: -tr_setup: + /* + * If output packets don't require headers (the common case) we + * can just load the buffer up with payload bytes all at once. + * Otherwise, loop to format packets into the buffer while there + * is data available, and room for a packet header and at least + * one byte of payload. + */ pc = usbd_xfer_get_frame(xfer, 0); - if (ucom_get_data(&sc->sc_ucom, pc, - sc->sc_hdrlen, UFTDI_OBUFSIZE - sc->sc_hdrlen, - &actlen)) { - - if (sc->sc_hdrlen > 0) { - buf[0] = - FTDI_OUT_TAG(actlen, sc->sc_ucom.sc_portno); - usbd_copy_in(pc, 0, buf, 1); + if (sc->sc_hdrlen == 0) { + ucom_get_data(&sc->sc_ucom, pc, 0, UFTDI_OBUFSIZE, + &buflen); + } else { + buflen = 0; + while (buflen < UFTDI_OBUFSIZE - sc->sc_hdrlen - 1 && + ucom_get_data(&sc->sc_ucom, pc, buflen + + sc->sc_hdrlen, UFTDI_OPKTSIZE - sc->sc_hdrlen, + &pktlen) != 0) { + buf[0] = FTDI_OUT_TAG(pktlen, + sc->sc_ucom.sc_portno); + usbd_copy_in(pc, buflen, buf, 1); + buflen += pktlen + sc->sc_hdrlen; } - usbd_xfer_set_frame_len(xfer, 0, actlen + sc->sc_hdrlen); - usbd_transfer_submit(xfer); } - return; - - default: /* Error */ - if (error != USB_ERR_CANCELLED) { - /* try to clear stall first */ - usbd_xfer_set_stall(xfer); - goto tr_setup; + if (buflen != 0) { + usbd_xfer_set_frame_len(xfer, 0, buflen); + usbd_transfer_submit(xfer); } - return; + break; } } @@ -1137,23 +1176,47 @@ uftdi_read_callback(struct usb_xfer *xfe uint8_t ftdi_msr; uint8_t msr; uint8_t lsr; - int actlen; + int buflen; + int pktlen; + int pktmax; + int offset; - usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL); + usbd_xfer_status(xfer, &buflen, NULL, NULL, NULL); switch (USB_GET_STATE(xfer)) { case USB_ST_TRANSFERRED: - - if (actlen < 2) { + if (buflen < UFTDI_IHDRSIZE) goto tr_setup; - } pc = usbd_xfer_get_frame(xfer, 0); - usbd_copy_out(pc, 0, buf, 2); - + pktmax = xfer->max_packet_size - UFTDI_IHDRSIZE; + lsr = 0; + msr = 0; + offset = 0; + /* + * Extract packet headers and payload bytes from the buffer. + * Feed payload bytes to ucom/tty layer; OR-accumulate header + * status bits which are transient and could toggle with each + * packet. After processing all packets in the buffer, process + * the accumulated transient MSR and LSR values along with the + * non-transient bits from the last packet header. + */ + while (buflen >= UFTDI_IHDRSIZE) { + usbd_copy_out(pc, offset, buf, UFTDI_IHDRSIZE); + offset += UFTDI_IHDRSIZE; + buflen -= UFTDI_IHDRSIZE; + lsr |= FTDI_GET_LSR(buf); + if (FTDI_GET_MSR(buf) & FTDI_SIO_RI_MASK) + msr |= SER_RI; + pktlen = min(buflen, pktmax); + if (pktlen != 0) { + ucom_put_data(&sc->sc_ucom, pc, offset, + pktlen); + offset += pktlen; + buflen -= pktlen; + } + } ftdi_msr = FTDI_GET_MSR(buf); - lsr = FTDI_GET_LSR(buf); - msr = 0; if (ftdi_msr & FTDI_SIO_CTS_MASK) msr |= SER_CTS; if (ftdi_msr & FTDI_SIO_DSR_MASK) @@ -1174,11 +1237,7 @@ uftdi_read_callback(struct usb_xfer *xfe ucom_status_change(&sc->sc_ucom); } - actlen -= 2; - - if (actlen > 0) { - ucom_put_data(&sc->sc_ucom, pc, 2, actlen); - } + /* FALLTHROUGH */ case USB_ST_SETUP: tr_setup: usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
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