Re: [Qemu-devel] [PATCH RFC v8 08/12] hw/char: RX62N serical communication interface (SCI)

[Alex Bennée]

Yoshinori Sato <address@hidden> writes:


nit: typo in subject (serical->serial)

> 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 <address@hidden>
> ---
>  include/hw/char/renesas_sci.h |  45 ++++++
>  hw/char/renesas_sci.c         | 341 
> ++++++++++++++++++++++++++++++++++++++++++
>  hw/char/Kconfig               |   3 +
>  hw/char/Makefile.objs         |   2 +-
>  4 files changed, 390 insertions(+), 1 deletion(-)
>  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..719fa2f938
> --- /dev/null
> +++ b/hw/char/renesas_sci.c
> @@ -0,0 +1,341 @@
> +/*
> + * Renesas Serial Communication Interface
> + *
> + * 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 "cpu.h"
> +#include "hw/hw.h"
> +#include "hw/sysbus.h"
> +#include "hw/registerfields.h"
> +#include "hw/char/renesas_sci.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]);
> +        }
> +    }
> +}
> +
> +static void send_byte(RSCIState *sci)
> +{
> +    if (qemu_chr_fe_backend_connected(&sci->chr)) {
> +        qemu_chr_fe_write_all(&sci->chr, &sci->tdr, 1);
> +    }
> +    timer_mod(sci->timer,
> +              qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + sci->trtime);
> +    sci->ssr = FIELD_DP8(sci->ssr, SSR, TEND, 0);
> +    sci->ssr = FIELD_DP8(sci->ssr, SSR, TDRE, 1);
> +    qemu_set_irq(sci->irq[TEI], 0);
> +    if (FIELD_EX8(sci->scr, SCR, TIE)) {
> +        qemu_irq_pulse(sci->irq[TXI]);
> +    }
> +}
> +
> +static void txend(void *opaque)
> +{
> +    RSCIState *sci = RSCI(opaque);
> +    if (!FIELD_EX8(sci->ssr, SSR, TDRE)) {
> +        send_byte(sci);
> +    } else {
> +        sci->ssr = FIELD_DP8(sci->ssr, SSR, TEND, 1);
> +        if (FIELD_EX8(sci->scr, SCR, TEIE)) {
> +            qemu_set_irq(sci->irq[TEI], 1);
> +        }
> +    }
> +}
> +
> +static void update_trtime(RSCIState *sci)
> +{
> +    /* char per bits */
> +    sci->trtime = 8 - FIELD_EX8(sci->smr, SMR, CHR);
> +    sci->trtime += FIELD_EX8(sci->smr, SMR, PE);
> +    sci->trtime += FIELD_EX8(sci->smr, SMR, STOP) + 1;
> +    /* x bit transmit time (32 * divrate * brr) / base freq */
> +    sci->trtime *= 32 * sci->brr;
> +    sci->trtime *= 1 << (2 * FIELD_EX8(sci->smr, SMR, CKS));
> +    sci->trtime *= NANOSECONDS_PER_SECOND;
> +    sci->trtime /= sci->input_freq;
> +}
> +
> +#define IS_TR_ENABLED(scr) \
> +    (FIELD_EX8(scr, SCR, TE) || FIELD_EX8(scr, SCR, RE))
> +
> +static void sci_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
> +{
> +    hwaddr offset = addr & 0x07;
> +    RSCIState *sci = RSCI(opaque);
> +
> +    switch (offset) {
> +    case A_SMR:
> +        if (!IS_TR_ENABLED(sci->scr)) {
> +            sci->smr = val;
> +            update_trtime(sci);
> +        }
> +        break;
> +    case A_BRR:
> +        if (!IS_TR_ENABLED(sci->scr)) {
> +            sci->brr = val;
> +            update_trtime(sci);
> +        }
> +        break;
> +    case A_SCR:
> +        sci->scr = val;
> +        if (FIELD_EX8(sci->scr, SCR, TE)) {
> +            sci->ssr = FIELD_DP8(sci->ssr, SSR, TDRE, 1);
> +            sci->ssr = FIELD_DP8(sci->ssr, SSR, TEND, 1);
> +            if (FIELD_EX8(sci->scr, SCR, TIE)) {
> +                qemu_irq_pulse(sci->irq[TXI]);
> +            }
> +        }
> +        if (!FIELD_EX8(sci->scr, SCR, TEIE)) {
> +            qemu_set_irq(sci->irq[TEI], 0);
> +        }
> +        if (!FIELD_EX8(sci->scr, SCR, RIE)) {
> +            qemu_set_irq(sci->irq[ERI], 0);
> +        }
> +        break;
> +    case A_TDR:
> +        sci->tdr = val;
> +        if (FIELD_EX8(sci->ssr, SSR, TEND)) {
> +            send_byte(sci);
> +        } else {
> +            sci->ssr = FIELD_DP8(sci->ssr, SSR, TDRE, 0);
> +        }
> +        break;
> +    case A_SSR:
> +        sci->ssr = FIELD_DP8(sci->ssr, SSR, MPBT,
> +                             FIELD_EX8(val, SSR, MPBT));
> +        sci->ssr = FIELD_DP8(sci->ssr, SSR, ERR,
> +                             FIELD_EX8(val, SSR, ERR) & 0x07);
> +        if (FIELD_EX8(sci->read_ssr, SSR, ERR) &&
> +            FIELD_EX8(sci->ssr, SSR, ERR) == 0) {
> +            qemu_set_irq(sci->irq[ERI], 0);
> +        }
> +        break;
> +    case A_RDR:
> +        qemu_log_mask(LOG_GUEST_ERROR, "reneas_sci: RDR is read only.\n");
> +        break;
> +    case A_SCMR:
> +        sci->scmr = val; break;
> +    case A_SEMR: /* SEMR */
> +        sci->semr = val; break;
> +    default:
> +        qemu_log_mask(LOG_UNIMP,
> +                      "renesas_sci: Register %08lx not implemented\n", 
> offset);
> +    }
> +}
> +
> +static uint64_t sci_read(void *opaque, hwaddr addr, unsigned size)
> +{
> +    hwaddr offset = addr & 0x07;
> +    RSCIState *sci = RSCI(opaque);
> +
> +    switch (offset) {
> +    case A_SMR:
> +        return sci->smr;
> +    case A_BRR:
> +        return sci->brr;
> +    case A_SCR:
> +        return sci->scr;
> +    case A_TDR:
> +        return sci->tdr;
> +    case A_SSR:
> +        sci->read_ssr = sci->ssr;
> +        return sci->ssr;
> +    case A_RDR:
> +        sci->ssr = FIELD_DP8(sci->ssr, SSR, RDRF, 0);
> +        return sci->rdr;
> +    case A_SCMR:
> +        return sci->scmr;
> +    case A_SEMR:
> +        return sci->semr;
> +    default:
> +        qemu_log_mask(LOG_UNIMP,
> +                      "renesas_sci: Register %08lx not implemented.\n", 
> offset);
> +    }
> +    return -1;
> +}
> +
> +static const MemoryRegionOps sci_ops = {
> +    .write = sci_write,
> +    .read  = sci_read,
> +    .endianness = DEVICE_NATIVE_ENDIAN,
> +    .impl = {
> +        .max_access_size = 1,
> +    },
> +};
> +
> +static void rsci_reset(DeviceState *dev)
> +{
> +    RSCIState *sci = RSCI(dev);
> +    sci->smr = sci->scr = 0x00;
> +    sci->brr = 0xff;
> +    sci->tdr = 0xff;
> +    sci->rdr = 0x00;
> +    sci->ssr = 0x84;
> +    sci->scmr = 0x00;
> +    sci->semr = 0x00;
> +    sci->rx_next = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
> +}
> +
> +static void sci_event(void *opaque, int event)
> +{
> +    RSCIState *sci = RSCI(opaque);
> +    if (event == CHR_EVENT_BREAK) {
> +        sci->ssr = FIELD_DP8(sci->ssr, SSR, FER, 1);
> +        printf("ssr %s %d %02x\n", __func__, __LINE__, sci->ssr);

stray debug printf

Otherwise:

Reviewed-by: Alex Bennée <address@hidden>

--
Alex Bennée