Date: Tue, 6 May 1997 23:35:48 +0400 (MSD) From: vak@cronyx.ru To: FreeBSD-gnats-submit@FreeBSD.ORG Subject: i386/3523: [patch] sio: automatic detection of 16550/16750 controllers Message-ID: <199705061935.XAA00455@crox.net.kiae.su> Resent-Message-ID: <199705061940.MAA00543@hub.freebsd.org>
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>Number: 3523
>Category: i386
>Synopsis: sio driver: added automatic detection of 16650/16750 UARTs
>Confidential: no
>Severity: non-critical
>Priority: medium
>Responsible: freebsd-bugs
>State: open
>Class: change-request
>Submitter-Id: current-users
>Arrival-Date: Tue May 6 12:40:01 PDT 1997
>Last-Modified:
>Originator: Serge V.Vakulenko
>Organization:
Cronyx Engineering Ltd.
>Release: FreeBSD 2.2.1-RELEASE i386
>Environment:
FreeBSD 2.2.1 with Cronyx-Omega multiport serial card
(Based on Startech 16c654 UARTs).
Or any other serial adapter with 16650 or 16750 chips.
>Description:
The driver detects UARTs as 16550A which is not correct.
>How-To-Repeat:
>Fix:
Apply the following patch:
--- sio221.c Sat Feb 1 19:19:05 1997
+++ sio.c Tue May 6 23:28:37 1997
@@ -856,12 +856,46 @@
printf(" 16550?");
break;
case FIFO_RX_HIGH:
- printf(" 16550A");
if (COM_NOFIFO(isdp)) {
- printf(" fifo disabled");
+ printf(" 16550A fifo disabled");
} else {
+ /* Detect the fifo size. */
+ int i, n;
+
+ /* Enable and reset the FIFO. */
+ outb (iobase+com_fifo, FIFO_ENABLE | FIFO_RCV_RST | FIFO_XMT_RST);
+
+ /* Set the loopback mode, 57600 baud. */
+ outb (iobase+com_cfcr, CFCR_DLAB);
+ outb (iobase+com_dlbh, 0);
+ outb (iobase+com_dlbl, 2);
+ outb (iobase+com_cfcr, CFCR_8BITS);
+ outb (iobase+com_mcr, MCR_LOOPBACK);
+ inb (iobase+com_lsr);
+
+ /* Put data into transmit FIFO and wait until overrun. */
+ for (i=n=0; i<20000; ++i) {
+ unsigned char lsr = inb (iobase+com_lsr);
+ if (lsr & LSR_OE)
+ break;
+ if (lsr & LSR_TXRDY) {
+ outb (iobase+com_data, 0x5A);
+ ++n;
+ }
+ }
+ outb (iobase+com_mcr, 0);
+ outb (iobase+com_fifo, 0);
+
com->hasfifo = TRUE;
- com->tx_fifo_size = 16;
+ if (n > 40) {
+ com->tx_fifo_size = 64;
+ printf(" 16750");
+ } else if (n > 24) {
+ com->tx_fifo_size = 32;
+ printf(" 16650");
+ } else
+ com->tx_fifo_size = 16;
+ printf(" 16550A");
#ifdef COM_ESP
for (espp = likely_esp_ports; *espp != 0; espp++)
if (espattach(isdp, com, *espp)) {
>Audit-Trail:
>Unformatted:
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