Re: com(4) over 115200 bps support

[KIYOHARA Takashi <kiyohara%kk.iij4u.or.jp@localhost>]

From: Thor Lancelot Simon <tls%panix.com@localhost>
Subject: Re: com(4) over 115200 bps support
Date: Mon, 1 Mar 2010 12:43:01 -0500

> On Mon, Mar 01, 2010 at 03:32:01PM +0900, KIYOHARA Takashi wrote:
> > Hi! all,

> with the 16550 FIFO depth.  Also you may want to check that the code
> for handling the automatic hardware flow control is working properly,
> it would be my best guess for what's currently not right.


I think that the reason why automatic flow control cannot be done is
this.  We should write 0xBF(EERS?) in LCR before the access to EFR.

        if (ISSET(sc->sc_hwflags, COM_HW_FLOW)) {
                KASSERT(sc->sc_type != COM_TYPE_AU1x00);
                KASSERT(sc->sc_type != COM_TYPE_16550_NOERS);
                /* no EFR on alchemy */
-               CSR_WRITE_1(regsp, COM_REG_EFR, sc->sc_efr);
                CSR_WRITE_1(regsp, COM_REG_LCR, LCR_EERS);
+               CSR_WRITE_1(regsp, COM_REG_EFR, sc->sc_efr);
        }

Thanks,
--
kiyohara