Re: [PATCH v32 16/22] hw/char: RX62N serial communication interface (SCI)

[Yoshinori Sato <ysato@users.sourceforge.jp>]

On Mon, 09 Mar 2020 00:41:45 +0900,
Philippe Mathieu-Daudé wrote:
> 
> Hi Yoshinori,
> 
> On 2/24/20 3:19 PM, Yoshinori Sato wrote:
> > This module supported only non FIFO type.
> > Hardware manual.
> > https://www.renesas.com/us/en/doc/products/mpumcu/doc/rx_family/r01uh0033ej0140_rx62n.pdf
> > 
> > Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
> > Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
> > Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> > Message-Id: <20190607091116.49044-8-ysato@users.sourceforge.jp>
> > Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> > Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> > ---
> >   include/hw/char/renesas_sci.h |  45 +++++
> >   hw/char/renesas_sci.c         | 342 ++++++++++++++++++++++++++++++++++
> >   hw/char/Kconfig               |   3 +
> >   hw/char/Makefile.objs         |   1 +
> >   4 files changed, 391 insertions(+)
> >   create mode 100644 include/hw/char/renesas_sci.h
> >   create mode 100644 hw/char/renesas_sci.c
> > 
> > diff --git a/include/hw/char/renesas_sci.h b/include/hw/char/renesas_sci.h
> > new file mode 100644
> > index 0000000000..50d1336944
> > --- /dev/null
> > +++ b/include/hw/char/renesas_sci.h
> > @@ -0,0 +1,45 @@
> > +/*
> > + * Renesas Serial Communication Interface
> > + *
> > + * Copyright (c) 2018 Yoshinori Sato
> > + *
> > + * This code is licensed under the GPL version 2 or later.
> > + *
> > + */
> > +
> > +#include "chardev/char-fe.h"
> > +#include "qemu/timer.h"
> > +#include "hw/sysbus.h"
> > +
> > +#define TYPE_RENESAS_SCI "renesas-sci"
> > +#define RSCI(obj) OBJECT_CHECK(RSCIState, (obj), TYPE_RENESAS_SCI)
> > +
> > +enum {
> > +    ERI = 0,
> > +    RXI = 1,
> > +    TXI = 2,
> > +    TEI = 3,
> > +    SCI_NR_IRQ = 4,
> > +};
> > +
> > +typedef struct {
> > +    SysBusDevice parent_obj;
> > +    MemoryRegion memory;
> > +
> > +    uint8_t smr;
> > +    uint8_t brr;
> > +    uint8_t scr;
> > +    uint8_t tdr;
> > +    uint8_t ssr;
> > +    uint8_t rdr;
> > +    uint8_t scmr;
> > +    uint8_t semr;
> > +
> > +    uint8_t read_ssr;
> > +    int64_t trtime;
> > +    int64_t rx_next;
> > +    QEMUTimer *timer;
> > +    CharBackend chr;
> > +    uint64_t input_freq;
> > +    qemu_irq irq[SCI_NR_IRQ];
> > +} RSCIState;
> > diff --git a/hw/char/renesas_sci.c b/hw/char/renesas_sci.c
> > new file mode 100644
> > index 0000000000..0760a51f43
> > --- /dev/null
> > +++ b/hw/char/renesas_sci.c
> > @@ -0,0 +1,342 @@
> > +/*
> > + * Renesas Serial Communication Interface
> 
> Looking at this again, have you looked at the SH model
> (hw/char/sh_serial.c)? This seems the same.
> (Similarly your timer model with hw/timer/sh_timer.c).
>

sh_serial has FIFO.
renesas_sci has no FIFO.
These are relationships like 8250 and 16550.
sh_serial is old,so I think it's better to implement
and integrate FIFO into renesas_sci.

> > + *
> > + * Datasheet: RX62N Group, RX621 Group User's Manual: Hardware
> > + * (Rev.1.40 R01UH0033EJ0140)
> > + *
> > + * Copyright (c) 2019 Yoshinori Sato
> > + *
> > + * This program is free software; you can redistribute it and/or modify it
> > + * under the terms and conditions of the GNU General Public License,
> > + * version 2 or later, as published by the Free Software Foundation.
> > + *
> > + * This program is distributed in the hope it will be useful, but WITHOUT
> > + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> > + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
> > + * more details.
> > + *
> > + * You should have received a copy of the GNU General Public License along with
> > + * this program.  If not, see <http://www.gnu.org/licenses/>.
> > + */
> > +
> > +#include "qemu/osdep.h"
> > +#include "qemu/log.h"
> > +#include "qapi/error.h"
> > +#include "qemu-common.h"
> > +#include "hw/hw.h"
> > +#include "hw/irq.h"
> > +#include "hw/sysbus.h"
> > +#include "hw/registerfields.h"
> > +#include "hw/qdev-properties.h"
> > +#include "hw/char/renesas_sci.h"
> > +#include "migration/vmstate.h"
> > +#include "qemu/error-report.h"
> > +
> > +/* SCI register map */
> > +REG8(SMR, 0)
> > +  FIELD(SMR, CKS,  0, 2)
> > +  FIELD(SMR, MP,   2, 1)
> > +  FIELD(SMR, STOP, 3, 1)
> > +  FIELD(SMR, PM,   4, 1)
> > +  FIELD(SMR, PE,   5, 1)
> > +  FIELD(SMR, CHR,  6, 1)
> > +  FIELD(SMR, CM,   7, 1)
> > +REG8(BRR, 1)
> > +REG8(SCR, 2)
> > +  FIELD(SCR, CKE, 0, 2)
> > +  FIELD(SCR, TEIE, 2, 1)
> > +  FIELD(SCR, MPIE, 3, 1)
> > +  FIELD(SCR, RE,   4, 1)
> > +  FIELD(SCR, TE,   5, 1)
> > +  FIELD(SCR, RIE,  6, 1)
> > +  FIELD(SCR, TIE,  7, 1)
> > +REG8(TDR, 3)
> > +REG8(SSR, 4)
> > +  FIELD(SSR, MPBT, 0, 1)
> > +  FIELD(SSR, MPB,  1, 1)
> > +  FIELD(SSR, TEND, 2, 1)
> > +  FIELD(SSR, ERR, 3, 3)
> > +    FIELD(SSR, PER,  3, 1)
> > +    FIELD(SSR, FER,  4, 1)
> > +    FIELD(SSR, ORER, 5, 1)
> > +  FIELD(SSR, RDRF, 6, 1)
> > +  FIELD(SSR, TDRE, 7, 1)
> > +REG8(RDR, 5)
> > +REG8(SCMR, 6)
> > +  FIELD(SCMR, SMIF, 0, 1)
> > +  FIELD(SCMR, SINV, 2, 1)
> > +  FIELD(SCMR, SDIR, 3, 1)
> > +  FIELD(SCMR, BCP2, 7, 1)
> > +REG8(SEMR, 7)
> > +  FIELD(SEMR, ACS0, 0, 1)
> > +  FIELD(SEMR, ABCS, 4, 1)
> > +
> > +static int can_receive(void *opaque)
> > +{
> > +    RSCIState *sci = RSCI(opaque);
> > +    if (sci->rx_next > qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL)) {
> > +        return 0;
> > +    } else {
> > +        return FIELD_EX8(sci->scr, SCR, RE);
> > +    }
> > +}
> > +
> > +static void receive(void *opaque, const uint8_t *buf, int size)
> > +{
> > +    RSCIState *sci = RSCI(opaque);
> > +    sci->rx_next = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + sci->trtime;
> > +    if (FIELD_EX8(sci->ssr, SSR, RDRF) || size > 1) {
> > +        sci->ssr = FIELD_DP8(sci->ssr, SSR, ORER, 1);
> > +        if (FIELD_EX8(sci->scr, SCR, RIE)) {
> > +            qemu_set_irq(sci->irq[ERI], 1);
> > +        }
> > +    } else {
> > +        sci->rdr = buf[0];
> > +        sci->ssr = FIELD_DP8(sci->ssr, SSR, RDRF, 1);
> > +        if (FIELD_EX8(sci->scr, SCR, RIE)) {
> > +            qemu_irq_pulse(sci->irq[RXI]);
> > +        }
> > +    }
> > +}
> [...]
> 
> 

-- 
Yosinori Sato