Module Name: src
Committed By: kiyohara
Date: Sun Sep 1 04:58:15 UTC 2013
Modified Files:
src/sys/dev/ic: com.c comreg.h
Log Message:
Add support 16750 64Byte FIFO. But not test.
To generate a diff of this commit:
cvs rdiff -u -r1.313 -r1.314 src/sys/dev/ic/com.c
cvs rdiff -u -r1.19 -r1.20 src/sys/dev/ic/comreg.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/ic/com.c
diff -u src/sys/dev/ic/com.c:1.313 src/sys/dev/ic/com.c:1.314
--- src/sys/dev/ic/com.c:1.313 Sun Sep 1 04:51:24 2013
+++ src/sys/dev/ic/com.c Sun Sep 1 04:58:15 2013
@@ -1,4 +1,4 @@
-/* $NetBSD: com.c,v 1.313 2013/09/01 04:51:24 kiyohara Exp $ */
+/* $NetBSD: com.c,v 1.314 2013/09/01 04:58:15 kiyohara Exp $ */
/*-
* Copyright (c) 1998, 1999, 2004, 2008 The NetBSD Foundation, Inc.
@@ -66,7 +66,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: com.c,v 1.313 2013/09/01 04:51:24 kiyohara Exp $");
+__KERNEL_RCSID(0, "$NetBSD: com.c,v 1.314 2013/09/01 04:58:15 kiyohara Exp $");
#include "opt_com.h"
#include "opt_ddb.h"
@@ -374,9 +374,7 @@ com_attach_subr(struct com_softc *sc)
{
struct com_regs *regsp = &sc->sc_regs;
struct tty *tp;
-#ifdef COM_16650
u_int8_t lcr;
-#endif
const char *fifo_msg = NULL;
prop_dictionary_t dict;
bool is_console = true;
@@ -480,6 +478,37 @@ com_attach_subr(struct com_softc *sc)
#endif
sc->sc_fifolen = 16;
+ /*
+ * TL16C750 can enable 64byte FIFO, only when DLAB
+ * is 1. However, some 16750 may always enable. For
+ * example, restrictions according to DLAB in a data
+ * sheet for SC16C750 were not described.
+ * Please enable 'options COM_16650', supposing you
+ * use SC16C750. Probably 32 bytes of FIFO and HW FLOW
+ * should become effective.
+ */
+ uint8_t iir1, iir2;
+ const uint8_t fcr = FIFO_ENABLE | FIFO_TRIGGER_14;
+
+ lcr = CSR_READ_1(regsp, COM_REG_LCR);
+ CSR_WRITE_1(regsp, COM_REG_LCR, lcr & ~LCR_DLAB);
+ CSR_WRITE_1(regsp, COM_REG_FIFO, fcr | FIFO_64B_ENABLE);
+ iir1 = CSR_READ_1(regsp, COM_REG_IIR);
+ CSR_WRITE_1(regsp, COM_REG_FIFO, fcr);
+ CSR_WRITE_1(regsp, COM_REG_LCR, lcr | LCR_DLAB);
+ CSR_WRITE_1(regsp, COM_REG_FIFO, fcr | FIFO_64B_ENABLE);
+ iir2 = CSR_READ_1(regsp, COM_REG_IIR);
+
+ CSR_WRITE_1(regsp, COM_REG_LCR, lcr);
+
+ if (!ISSET(iir1, IIR_64B_FIFO) &&
+ ISSET(iir2, IIR_64B_FIFO)) {
+ /* It is TL16C750. */
+ sc->sc_fifolen = 64;
+ SET(sc->sc_hwflags, COM_HW_FLOW);
+ } else
+ CSR_WRITE_1(regsp, COM_REG_FIFO, fcr);
+
#ifdef COM_16650
CSR_WRITE_1(regsp, COM_REG_LCR, lcr);
if (sc->sc_fifolen == 0)
@@ -488,6 +517,9 @@ com_attach_subr(struct com_softc *sc)
fifo_msg = "st16650a, working fifo";
else
#endif
+ if (sc->sc_fifolen == 64)
+ fifo_msg = "tl16c750, working fifo";
+ else
fifo_msg = "ns16550a, working fifo";
} else
fifo_msg = "ns16550, broken fifo";
Index: src/sys/dev/ic/comreg.h
diff -u src/sys/dev/ic/comreg.h:1.19 src/sys/dev/ic/comreg.h:1.20
--- src/sys/dev/ic/comreg.h:1.19 Sun Sep 1 04:51:24 2013
+++ src/sys/dev/ic/comreg.h Sun Sep 1 04:58:15 2013
@@ -1,4 +1,4 @@
-/* $NetBSD: comreg.h,v 1.19 2013/09/01 04:51:24 kiyohara Exp $ */
+/* $NetBSD: comreg.h,v 1.20 2013/09/01 04:58:15 kiyohara Exp $ */
/*-
* Copyright (c) 1991 The Regents of the University of California.
@@ -63,6 +63,7 @@
#define IIR_TXRDY 0x2 /* Transmitter ready */
#define IIR_MLSC 0x0 /* Modem status */
#define IIR_NOPEND 0x1 /* No pending interrupts */
+#define IIR_64B_FIFO 0x20 /* 64byte FIFO Enabled (16750) */
#define IIR_FIFO_MASK 0xc0 /* set if FIFOs are enabled */
/* fifo control register */
@@ -70,6 +71,7 @@
#define FIFO_RCV_RST 0x02 /* Reset RX FIFO */
#define FIFO_XMT_RST 0x04 /* Reset TX FIFO */
#define FIFO_DMA_MODE 0x08
+#define FIFO_64B_ENABLE 0x20 /* 64byte FIFO Enable (16750) */
#define FIFO_TRIGGER_1 0x00 /* Trigger RXRDY intr on 1 character */
#define FIFO_TRIGGER_4 0x40 /* ibid 4 */
#define FIFO_TRIGGER_8 0x80 /* ibid 8 */
