diff mbox series

[2/3] hw/char: Add Shakti UART emulation

Message ID 20210314083936.76269-3-vijai@behindbytes.com (mailing list archive)
State New, archived
Headers show
Series Add support for Shakti SoC from IIT-M | expand

Commit Message

Vijai Kumar K March 14, 2021, 8:39 a.m. UTC
This is the initial implementation of Shakti UART.

TX tested and works fine. RX is untested.

Signed-off-by: Vijai Kumar K <vijai@behindbytes.com>
---
 MAINTAINERS                   |   2 +
 hw/char/meson.build           |   1 +
 hw/char/shakti_uart.c         | 204 ++++++++++++++++++++++++++++++++++
 hw/char/trace-events          |   4 +
 include/hw/char/shakti_uart.h |  74 ++++++++++++
 5 files changed, 285 insertions(+)
 create mode 100644 hw/char/shakti_uart.c
 create mode 100644 include/hw/char/shakti_uart.h

Comments

Alistair Francis March 19, 2021, 1:44 p.m. UTC | #1
On Sun, Mar 14, 2021 at 5:14 AM Vijai Kumar K <vijai@behindbytes.com> wrote:
>
> This is the initial implementation of Shakti UART.
>
> TX tested and works fine. RX is untested.
>
> Signed-off-by: Vijai Kumar K <vijai@behindbytes.com>
> ---
>  MAINTAINERS                   |   2 +
>  hw/char/meson.build           |   1 +
>  hw/char/shakti_uart.c         | 204 ++++++++++++++++++++++++++++++++++
>  hw/char/trace-events          |   4 +
>  include/hw/char/shakti_uart.h |  74 ++++++++++++
>  5 files changed, 285 insertions(+)
>  create mode 100644 hw/char/shakti_uart.c
>  create mode 100644 include/hw/char/shakti_uart.h
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 9f71c4cc3f..be084865db 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1385,7 +1385,9 @@ M: Vijai Kumar K <vijai@behindbytes.com>
>  L: qemu-riscv@nongnu.org
>  S: Supported
>  F: hw/riscv/shakti_c.c
> +F: hw/char/shakti_uart.c
>  F: include/hw/riscv/shakti_c.h
> +F: include/hw/char/shakti_uart.h
>
>  SiFive Machines
>  M: Alistair Francis <Alistair.Francis@wdc.com>
> diff --git a/hw/char/meson.build b/hw/char/meson.build
> index 7ba38dbd96..61c43d4b51 100644
> --- a/hw/char/meson.build
> +++ b/hw/char/meson.build
> @@ -19,6 +19,7 @@ softmmu_ss.add(when: 'CONFIG_SERIAL', if_true: files('serial.c'))
>  softmmu_ss.add(when: 'CONFIG_SERIAL_ISA', if_true: files('serial-isa.c'))
>  softmmu_ss.add(when: 'CONFIG_SERIAL_PCI', if_true: files('serial-pci.c'))
>  softmmu_ss.add(when: 'CONFIG_SERIAL_PCI_MULTI', if_true: files('serial-pci-multi.c'))
> +softmmu_ss.add(when: 'CONFIG_SHAKTI', if_true: files('shakti_uart.c'))
>  softmmu_ss.add(when: 'CONFIG_VIRTIO_SERIAL', if_true: files('virtio-console.c'))
>  softmmu_ss.add(when: 'CONFIG_XEN', if_true: files('xen_console.c'))
>  softmmu_ss.add(when: 'CONFIG_XILINX', if_true: files('xilinx_uartlite.c'))
> diff --git a/hw/char/shakti_uart.c b/hw/char/shakti_uart.c
> new file mode 100644
> index 0000000000..e1c72e8747
> --- /dev/null
> +++ b/hw/char/shakti_uart.c
> @@ -0,0 +1,204 @@
> +/*
> + * SHAKTI UART
> + *
> + * Copyright (c) 2021 Vijai Kumar K <vijai@behindbytes.com>
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a copy
> + * of this software and associated documentation files (the "Software"), to deal
> + * in the Software without restriction, including without limitation the rights
> + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
> + * copies of the Software, and to permit persons to whom the Software is
> + * furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
> + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
> + * THE SOFTWARE.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "hw/char/shakti_uart.h"
> +#include "hw/qdev-properties.h"
> +#include "hw/qdev-properties-system.h"
> +#include "qemu/log.h"
> +
> +#define DEBUG_SHAKTI_UART 0
> +#define DPRINTF(fmt, args...) \
> +    do { \
> +        if (DEBUG_SHAKTI_UART) { \
> +            fprintf(stderr, "[%s]%s: " fmt , TYPE_SHAKTI_UART, \
> +                                             __func__, ##args); \
> +        } \
> +    } while (0)

Can you use the trace infrastructure instead?

https://gitlab.com/qemu-project/qemu/-/blob/master/docs/devel/tracing.rst

> +
> +static uint64_t shakti_uart_read(void *opaque, hwaddr addr, unsigned size)
> +{
> +    ShaktiUartState *s = opaque;
> +    uint64_t retvalue = 0;
> +
> +    switch (addr) {
> +    case SHAKTI_UART_BAUD:
> +        return s->uart_baud;
> +        break;

You don't need a return and a break.

Also if you return in each one you don't need the retvalue variable.

> +    case SHAKTI_UART_RX:
> +        retvalue = s->uart_rx;
> +        qemu_chr_fe_accept_input(&s->chr);
> +        s->uart_status &= ~SHAKTI_UART_STATUS_RX_NOT_EMPTY;
> +        return retvalue;
> +        break;
> +    case SHAKTI_UART_STATUS:
> +        DPRINTF("uart_status: value = 0x%x)\n", s->uart_status);
> +        return s->uart_status;
> +        break;
> +    case SHAKTI_UART_DELAY:
> +        return s->uart_delay;
> +        break;
> +    case SHAKTI_UART_CONTROL:
> +        return s->uart_control;
> +        break;
> +    case SHAKTI_UART_INT_EN:
> +        return s->uart_interrupt;
> +        break;
> +    case SHAKTI_UART_IQ_CYCLES:
> +        return s->uart_iq_cycles;
> +        break;
> +    case SHAKTI_UART_RX_THRES:
> +        return s->uart_rx_threshold;
> +        break;
> +    default:
> +        /* Also handles TX REG which is write only */
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                      "%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, addr);

Maybe add a seperate log for TX then?

Alistair

> +    }
> +
> +    return 0;
> +}
> +
> +static void shakti_uart_write(void *opaque, hwaddr addr,
> +                              uint64_t data, unsigned size)
> +{
> +    ShaktiUartState *s = opaque;
> +    uint32_t value = data;
> +    uint8_t ch;
> +
> +    switch (addr) {
> +    case SHAKTI_UART_BAUD:
> +        s->uart_baud = value;
> +        break;
> +    case SHAKTI_UART_TX:
> +        ch = value;
> +        qemu_chr_fe_write_all(&s->chr, &ch, 1);
> +        s->uart_status &= ~SHAKTI_UART_STATUS_TX_FULL;
> +        break;
> +    case SHAKTI_UART_STATUS:
> +        s->uart_status = value;
> +        break;
> +    case SHAKTI_UART_DELAY:
> +        s->uart_delay = value;
> +        break;
> +    case SHAKTI_UART_CONTROL:
> +        s->uart_control = value;
> +        break;
> +    case SHAKTI_UART_INT_EN:
> +        s->uart_interrupt = value;
> +        break;
> +    case SHAKTI_UART_IQ_CYCLES:
> +        s->uart_iq_cycles = value;
> +        break;
> +    case SHAKTI_UART_RX_THRES:
> +        s->uart_rx_threshold = value;
> +        break;
> +    default:
> +        /* Also handles TX REG which is write only */
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                      "%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, addr);
> +    }
> +}
> +
> +static const MemoryRegionOps shakti_uart_ops = {
> +    .read = shakti_uart_read,
> +    .write = shakti_uart_write,
> +    .endianness = DEVICE_NATIVE_ENDIAN,
> +    .impl = {.min_access_size = 1, .max_access_size = 4},
> +    .valid = {.min_access_size = 1, .max_access_size = 4},
> +};
> +
> +static void shakti_uart_reset(DeviceState *dev)
> +{
> +    ShaktiUartState *s = SHAKTI_UART(dev);
> +
> +    s->uart_baud = SHAKTI_UART_BAUD_DEFAULT;
> +    s->uart_tx = 0x0;
> +    s->uart_rx = 0x0;
> +    s->uart_status = 0x0000;
> +    s->uart_delay = 0x0000;
> +    s->uart_control = SHAKTI_UART_CONTROL_DEFAULT;
> +    s->uart_interrupt = 0x0000;
> +    s->uart_iq_cycles = 0x00;
> +    s->uart_rx_threshold = 0x00;
> +}
> +
> +static int shakti_uart_can_receive(void *opaque)
> +{
> +    return 1;
> +}
> +
> +static void shakti_uart_receive(void *opaque, const uint8_t *buf, int size)
> +{
> +    ShaktiUartState *s = opaque;
> +
> +    s->uart_rx = *buf;
> +    s->uart_status |= SHAKTI_UART_STATUS_RX_NOT_EMPTY;
> +}
> +
> +static void shakti_uart_realize(DeviceState *dev, Error **errp)
> +{
> +    ShaktiUartState *sus = SHAKTI_UART(dev);
> +    qemu_chr_fe_set_handlers(&sus->chr, shakti_uart_can_receive,
> +                             shakti_uart_receive, NULL, NULL, sus, NULL, true);
> +}
> +
> +static void shakti_uart_instance_init(Object *obj)
> +{
> +    ShaktiUartState *sus = SHAKTI_UART(obj);
> +    memory_region_init_io(&sus->mmio,
> +                          obj,
> +                          &shakti_uart_ops,
> +                          sus,
> +                          TYPE_SHAKTI_UART,
> +                          0x1000);
> +    sysbus_init_mmio(SYS_BUS_DEVICE(obj), &sus->mmio);
> +}
> +
> +static Property shakti_uart_properties[] = {
> +    DEFINE_PROP_CHR("chardev", ShaktiUartState, chr),
> +    DEFINE_PROP_END_OF_LIST(),
> +};
> +
> +static void shakti_uart_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +    dc->reset = shakti_uart_reset;
> +    dc->realize = shakti_uart_realize;
> +    device_class_set_props(dc, shakti_uart_properties);
> +}
> +
> +static const TypeInfo shakti_uart_info = {
> +    .name = TYPE_SHAKTI_UART,
> +    .parent = TYPE_SYS_BUS_DEVICE,
> +    .instance_size = sizeof(ShaktiUartState),
> +    .class_init = shakti_uart_class_init,
> +    .instance_init = shakti_uart_instance_init,
> +};
> +
> +static void shakti_uart_register_types(void)
> +{
> +    type_register_static(&shakti_uart_info);
> +}
> +type_init(shakti_uart_register_types)
> diff --git a/hw/char/trace-events b/hw/char/trace-events
> index 81026f6612..54aeeb899c 100644
> --- a/hw/char/trace-events
> +++ b/hw/char/trace-events
> @@ -80,6 +80,10 @@ cmsdk_apb_uart_set_params(int speed) "CMSDK APB UART: params set to %d 8N1"
>  nrf51_uart_read(uint64_t addr, uint64_t r, unsigned int size) "addr 0x%" PRIx64 " value 0x%" PRIx64 " size %u"
>  nrf51_uart_write(uint64_t addr, uint64_t value, unsigned int size) "addr 0x%" PRIx64 " value 0x%" PRIx64 " size %u"
>
> +# shakti_uart.c
> +shakti_uart_read(uint64_t addr, uint16_t r, unsigned int size) "addr 0x%" PRIx64 " value 0x%" PRIx16 " size %u"
> +shakti_uart_write(uint64_t addr, uint64_t value, unsigned int size) "addr 0x%" PRIx64 " value 0x%" PRIx64 " size %u"
> +
>  # exynos4210_uart.c
>  exynos_uart_dmabusy(uint32_t channel) "UART%d: DMA busy (Rx buffer empty)"
>  exynos_uart_dmaready(uint32_t channel) "UART%d: DMA ready"
> diff --git a/include/hw/char/shakti_uart.h b/include/hw/char/shakti_uart.h
> new file mode 100644
> index 0000000000..526c408233
> --- /dev/null
> +++ b/include/hw/char/shakti_uart.h
> @@ -0,0 +1,74 @@
> +/*
> + * SHAKTI UART
> + *
> + * Copyright (c) 2021 Vijai Kumar K <vijai@behindbytes.com>
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a copy
> + * of this software and associated documentation files (the "Software"), to deal
> + * in the Software without restriction, including without limitation the rights
> + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
> + * copies of the Software, and to permit persons to whom the Software is
> + * furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
> + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
> + * THE SOFTWARE.
> + */
> +
> +#ifndef HW_SHAKTI_UART_H
> +#define HW_SHAKTI_UART_H
> +
> +#include "hw/sysbus.h"
> +#include "chardev/char-fe.h"
> +
> +#define SHAKTI_UART_BAUD        0x00
> +#define SHAKTI_UART_TX          0x04
> +#define SHAKTI_UART_RX          0x08
> +#define SHAKTI_UART_STATUS      0x0C
> +#define SHAKTI_UART_DELAY       0x10
> +#define SHAKTI_UART_CONTROL     0x14
> +#define SHAKTI_UART_INT_EN      0x18
> +#define SHAKTI_UART_IQ_CYCLES   0x1C
> +#define SHAKTI_UART_RX_THRES    0x20
> +
> +#define SHAKTI_UART_STATUS_TX_EMPTY     (1 << 0)
> +#define SHAKTI_UART_STATUS_TX_FULL      (1 << 1)
> +#define SHAKTI_UART_STATUS_RX_NOT_EMPTY (1 << 2)
> +#define SHAKTI_UART_STATUS_RX_FULL      (1 << 3)
> +/* 9600 8N1 is the default setting */
> +/* Reg value = (50000000 Hz)/(16 * 9600)*/
> +#define SHAKTI_UART_BAUD_DEFAULT    0x0145
> +#define SHAKTI_UART_CONTROL_DEFAULT 0x0100
> +
> +#define TYPE_SHAKTI_UART "shakti-uart"
> +#define SHAKTI_UART(obj) \
> +    OBJECT_CHECK(ShaktiUartState, (obj), TYPE_SHAKTI_UART)
> +
> +typedef struct {
> +    /* <private> */
> +    SysBusDevice parent_obj;
> +
> +    /* <public> */
> +    MemoryRegion mmio;
> +
> +    uint32_t uart_baud;
> +    uint32_t uart_tx;
> +    uint32_t uart_rx;
> +    uint32_t uart_status;
> +    uint32_t uart_delay;
> +    uint32_t uart_control;
> +    uint32_t uart_interrupt;
> +    uint32_t uart_iq_cycles;
> +    uint32_t uart_rx_threshold;
> +
> +    CharBackend chr;
> +} ShaktiUartState;
> +
> +#endif /* HW_SHAKTI_UART_H */
> --
> 2.25.1
>
>
>
Vijai Kumar K March 20, 2021, 9:41 a.m. UTC | #2
---- On Fri, 19 Mar 2021 19:14:31 +0530 Alistair Francis <alistair23@gmail.com> wrote ----

 > On Sun, Mar 14, 2021 at 5:14 AM Vijai Kumar K <vijai@behindbytes.com> wrote: 
 > > 
 > > This is the initial implementation of Shakti UART. 
 > > 
 > > TX tested and works fine. RX is untested. 
 > > 
 > > Signed-off-by: Vijai Kumar K <vijai@behindbytes.com> 
 > > --- 
 > >  MAINTAINERS                   |   2 + 
 > >  hw/char/meson.build           |   1 + 
 > >  hw/char/shakti_uart.c         | 204 ++++++++++++++++++++++++++++++++++ 
 > >  hw/char/trace-events          |   4 + 
 > >  include/hw/char/shakti_uart.h |  74 ++++++++++++ 
 > >  5 files changed, 285 insertions(+) 
 > >  create mode 100644 hw/char/shakti_uart.c 
 > >  create mode 100644 include/hw/char/shakti_uart.h 
 > > 
 > > diff --git a/MAINTAINERS b/MAINTAINERS 
 > > index 9f71c4cc3f..be084865db 100644 
 > > --- a/MAINTAINERS 
 > > +++ b/MAINTAINERS 
 > > @@ -1385,7 +1385,9 @@ M: Vijai Kumar K <vijai@behindbytes.com> 
 > >  L: qemu-riscv@nongnu.org 
 > >  S: Supported 
 > >  F: hw/riscv/shakti_c.c 
 > > +F: hw/char/shakti_uart.c 
 > >  F: include/hw/riscv/shakti_c.h 
 > > +F: include/hw/char/shakti_uart.h 
 > > 
 > >  SiFive Machines 
 > >  M: Alistair Francis <Alistair.Francis@wdc.com> 
 > > diff --git a/hw/char/meson.build b/hw/char/meson.build 
 > > index 7ba38dbd96..61c43d4b51 100644 
 > > --- a/hw/char/meson.build 
 > > +++ b/hw/char/meson.build 
 > > @@ -19,6 +19,7 @@ softmmu_ss.add(when: 'CONFIG_SERIAL', if_true: files('serial.c')) 
 > >  softmmu_ss.add(when: 'CONFIG_SERIAL_ISA', if_true: files('serial-isa.c')) 
 > >  softmmu_ss.add(when: 'CONFIG_SERIAL_PCI', if_true: files('serial-pci.c')) 
 > >  softmmu_ss.add(when: 'CONFIG_SERIAL_PCI_MULTI', if_true: files('serial-pci-multi.c')) 
 > > +softmmu_ss.add(when: 'CONFIG_SHAKTI', if_true: files('shakti_uart.c')) 
 > >  softmmu_ss.add(when: 'CONFIG_VIRTIO_SERIAL', if_true: files('virtio-console.c')) 
 > >  softmmu_ss.add(when: 'CONFIG_XEN', if_true: files('xen_console.c')) 
 > >  softmmu_ss.add(when: 'CONFIG_XILINX', if_true: files('xilinx_uartlite.c')) 
 > > diff --git a/hw/char/shakti_uart.c b/hw/char/shakti_uart.c 
 > > new file mode 100644 
 > > index 0000000000..e1c72e8747 
 > > --- /dev/null 
 > > +++ b/hw/char/shakti_uart.c 
 > > @@ -0,0 +1,204 @@ 
 > > +/* 
 > > + * SHAKTI UART 
 > > + * 
 > > + * Copyright (c) 2021 Vijai Kumar K <vijai@behindbytes.com> 
 > > + * 
 > > + * Permission is hereby granted, free of charge, to any person obtaining a copy 
 > > + * of this software and associated documentation files (the "Software"), to deal 
 > > + * in the Software without restriction, including without limitation the rights 
 > > + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 
 > > + * copies of the Software, and to permit persons to whom the Software is 
 > > + * furnished to do so, subject to the following conditions: 
 > > + * 
 > > + * The above copyright notice and this permission notice shall be included in 
 > > + * all copies or substantial portions of the Software. 
 > > + * 
 > > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
 > > + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
 > > + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 
 > > + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
 > > + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
 > > + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 
 > > + * THE SOFTWARE. 
 > > + */ 
 > > + 
 > > +#include "qemu/osdep.h" 
 > > +#include "hw/char/shakti_uart.h" 
 > > +#include "hw/qdev-properties.h" 
 > > +#include "hw/qdev-properties-system.h" 
 > > +#include "qemu/log.h" 
 > > + 
 > > +#define DEBUG_SHAKTI_UART 0 
 > > +#define DPRINTF(fmt, args...) \ 
 > > +    do { \ 
 > > +        if (DEBUG_SHAKTI_UART) { \ 
 > > +            fprintf(stderr, "[%s]%s: " fmt , TYPE_SHAKTI_UART, \ 
 > > +                                             __func__, ##args); \ 
 > > +        } \ 
 > > +    } while (0) 
 >  
 > Can you use the trace infrastructure instead? 
 >  
 > https://gitlab.com/qemu-project/qemu/-/blob/master/docs/devel/tracing.rst

I felt the tracing infra was a bit difficult to work with in this scenario, hence the DPRINTF. 
This is not needed anymore. I will drop the DPRINTF logs.

 >  
 >  
 > > + 
 > > +static uint64_t shakti_uart_read(void *opaque, hwaddr addr, unsigned size) 
 > > +{ 
 > > +    ShaktiUartState *s = opaque; 
 > > +    uint64_t retvalue = 0; 
 > > + 
 > > +    switch (addr) { 
 > > +    case SHAKTI_UART_BAUD: 
 > > +        return s->uart_baud; 
 > > +        break; 
 >  
 > You don't need a return and a break. 
 >  
 > Also if you return in each one you don't need the retvalue variable. 

Yes. Will drop it.

 >  
 > > +    case SHAKTI_UART_RX: 
 > > +        retvalue = s->uart_rx; 
 > > +        qemu_chr_fe_accept_input(&s->chr); 
 > > +        s->uart_status &= ~SHAKTI_UART_STATUS_RX_NOT_EMPTY; 
 > > +        return retvalue; 
 > > +        break; 
 > > +    case SHAKTI_UART_STATUS: 
 > > +        DPRINTF("uart_status: value = 0x%x)\n", s->uart_status); 
 > > +        return s->uart_status; 
 > > +        break; 
 > > +    case SHAKTI_UART_DELAY: 
 > > +        return s->uart_delay; 
 > > +        break; 
 > > +    case SHAKTI_UART_CONTROL: 
 > > +        return s->uart_control; 
 > > +        break; 
 > > +    case SHAKTI_UART_INT_EN: 
 > > +        return s->uart_interrupt; 
 > > +        break; 
 > > +    case SHAKTI_UART_IQ_CYCLES: 
 > > +        return s->uart_iq_cycles; 
 > > +        break; 
 > > +    case SHAKTI_UART_RX_THRES: 
 > > +        return s->uart_rx_threshold; 
 > > +        break; 
 > > +    default: 
 > > +        /* Also handles TX REG which is write only */ 
 > > +        qemu_log_mask(LOG_GUEST_ERROR, 
 > > +                      "%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, addr); 
 >  
 > Maybe add a seperate log for TX then? 
 >  
 > Alistair 

I believe this is sufficient. Anyway we are going to throw the same log.

Thanks,
Vijai  Kumar K

 >  
 > > +    } 
 > > + 
 > > +    return 0; 
 > > +} 
 > > + 
 > > +static void shakti_uart_write(void *opaque, hwaddr addr, 
 > > +                              uint64_t data, unsigned size) 
 > > +{ 
 > > +    ShaktiUartState *s = opaque; 
 > > +    uint32_t value = data; 
 > > +    uint8_t ch; 
 > > + 
 > > +    switch (addr) { 
 > > +    case SHAKTI_UART_BAUD: 
 > > +        s->uart_baud = value; 
 > > +        break; 
 > > +    case SHAKTI_UART_TX: 
 > > +        ch = value; 
 > > +        qemu_chr_fe_write_all(&s->chr, &ch, 1); 
 > > +        s->uart_status &= ~SHAKTI_UART_STATUS_TX_FULL; 
 > > +        break; 
 > > +    case SHAKTI_UART_STATUS: 
 > > +        s->uart_status = value; 
 > > +        break; 
 > > +    case SHAKTI_UART_DELAY: 
 > > +        s->uart_delay = value; 
 > > +        break; 
 > > +    case SHAKTI_UART_CONTROL: 
 > > +        s->uart_control = value; 
 > > +        break; 
 > > +    case SHAKTI_UART_INT_EN: 
 > > +        s->uart_interrupt = value; 
 > > +        break; 
 > > +    case SHAKTI_UART_IQ_CYCLES: 
 > > +        s->uart_iq_cycles = value; 
 > > +        break; 
 > > +    case SHAKTI_UART_RX_THRES: 
 > > +        s->uart_rx_threshold = value; 
 > > +        break; 
 > > +    default: 
 > > +        /* Also handles TX REG which is write only */ 
 > > +        qemu_log_mask(LOG_GUEST_ERROR, 
 > > +                      "%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, addr); 
 > > +    } 
 > > +} 
 > > + 
 > > +static const MemoryRegionOps shakti_uart_ops = { 
 > > +    .read = shakti_uart_read, 
 > > +    .write = shakti_uart_write, 
 > > +    .endianness = DEVICE_NATIVE_ENDIAN, 
 > > +    .impl = {.min_access_size = 1, .max_access_size = 4}, 
 > > +    .valid = {.min_access_size = 1, .max_access_size = 4}, 
 > > +}; 
 > > + 
 > > +static void shakti_uart_reset(DeviceState *dev) 
 > > +{ 
 > > +    ShaktiUartState *s = SHAKTI_UART(dev); 
 > > + 
 > > +    s->uart_baud = SHAKTI_UART_BAUD_DEFAULT; 
 > > +    s->uart_tx = 0x0; 
 > > +    s->uart_rx = 0x0; 
 > > +    s->uart_status = 0x0000; 
 > > +    s->uart_delay = 0x0000; 
 > > +    s->uart_control = SHAKTI_UART_CONTROL_DEFAULT; 
 > > +    s->uart_interrupt = 0x0000; 
 > > +    s->uart_iq_cycles = 0x00; 
 > > +    s->uart_rx_threshold = 0x00; 
 > > +} 
 > > + 
 > > +static int shakti_uart_can_receive(void *opaque) 
 > > +{ 
 > > +    return 1; 
 > > +} 
 > > + 
 > > +static void shakti_uart_receive(void *opaque, const uint8_t *buf, int size) 
 > > +{ 
 > > +    ShaktiUartState *s = opaque; 
 > > + 
 > > +    s->uart_rx = *buf; 
 > > +    s->uart_status |= SHAKTI_UART_STATUS_RX_NOT_EMPTY; 
 > > +} 
 > > + 
 > > +static void shakti_uart_realize(DeviceState *dev, Error **errp) 
 > > +{ 
 > > +    ShaktiUartState *sus = SHAKTI_UART(dev); 
 > > +    qemu_chr_fe_set_handlers(&sus->chr, shakti_uart_can_receive, 
 > > +                             shakti_uart_receive, NULL, NULL, sus, NULL, true); 
 > > +} 
 > > + 
 > > +static void shakti_uart_instance_init(Object *obj) 
 > > +{ 
 > > +    ShaktiUartState *sus = SHAKTI_UART(obj); 
 > > +    memory_region_init_io(&sus->mmio, 
 > > +                          obj, 
 > > +                          &shakti_uart_ops, 
 > > +                          sus, 
 > > +                          TYPE_SHAKTI_UART, 
 > > +                          0x1000); 
 > > +    sysbus_init_mmio(SYS_BUS_DEVICE(obj), &sus->mmio); 
 > > +} 
 > > + 
 > > +static Property shakti_uart_properties[] = { 
 > > +    DEFINE_PROP_CHR("chardev", ShaktiUartState, chr), 
 > > +    DEFINE_PROP_END_OF_LIST(), 
 > > +}; 
 > > + 
 > > +static void shakti_uart_class_init(ObjectClass *klass, void *data) 
 > > +{ 
 > > +    DeviceClass *dc = DEVICE_CLASS(klass); 
 > > +    dc->reset = shakti_uart_reset; 
 > > +    dc->realize = shakti_uart_realize; 
 > > +    device_class_set_props(dc, shakti_uart_properties); 
 > > +} 
 > > + 
 > > +static const TypeInfo shakti_uart_info = { 
 > > +    .name = TYPE_SHAKTI_UART, 
 > > +    .parent = TYPE_SYS_BUS_DEVICE, 
 > > +    .instance_size = sizeof(ShaktiUartState), 
 > > +    .class_init = shakti_uart_class_init, 
 > > +    .instance_init = shakti_uart_instance_init, 
 > > +}; 
 > > + 
 > > +static void shakti_uart_register_types(void) 
 > > +{ 
 > > +    type_register_static(&shakti_uart_info); 
 > > +} 
 > > +type_init(shakti_uart_register_types) 
 > > diff --git a/hw/char/trace-events b/hw/char/trace-events 
 > > index 81026f6612..54aeeb899c 100644 
 > > --- a/hw/char/trace-events 
 > > +++ b/hw/char/trace-events 
 > > @@ -80,6 +80,10 @@ cmsdk_apb_uart_set_params(int speed) "CMSDK APB UART: params set to %d 8N1" 
 > >  nrf51_uart_read(uint64_t addr, uint64_t r, unsigned int size) "addr 0x%" PRIx64 " value 0x%" PRIx64 " size %u" 
 > >  nrf51_uart_write(uint64_t addr, uint64_t value, unsigned int size) "addr 0x%" PRIx64 " value 0x%" PRIx64 " size %u" 
 > > 
 > > +# shakti_uart.c 
 > > +shakti_uart_read(uint64_t addr, uint16_t r, unsigned int size) "addr 0x%" PRIx64 " value 0x%" PRIx16 " size %u" 
 > > +shakti_uart_write(uint64_t addr, uint64_t value, unsigned int size) "addr 0x%" PRIx64 " value 0x%" PRIx64 " size %u" 
 > > + 
 > >  # exynos4210_uart.c 
 > >  exynos_uart_dmabusy(uint32_t channel) "UART%d: DMA busy (Rx buffer empty)" 
 > >  exynos_uart_dmaready(uint32_t channel) "UART%d: DMA ready" 
 > > diff --git a/include/hw/char/shakti_uart.h b/include/hw/char/shakti_uart.h 
 > > new file mode 100644 
 > > index 0000000000..526c408233 
 > > --- /dev/null 
 > > +++ b/include/hw/char/shakti_uart.h 
 > > @@ -0,0 +1,74 @@ 
 > > +/* 
 > > + * SHAKTI UART 
 > > + * 
 > > + * Copyright (c) 2021 Vijai Kumar K <vijai@behindbytes.com> 
 > > + * 
 > > + * Permission is hereby granted, free of charge, to any person obtaining a copy 
 > > + * of this software and associated documentation files (the "Software"), to deal 
 > > + * in the Software without restriction, including without limitation the rights 
 > > + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 
 > > + * copies of the Software, and to permit persons to whom the Software is 
 > > + * furnished to do so, subject to the following conditions: 
 > > + * 
 > > + * The above copyright notice and this permission notice shall be included in 
 > > + * all copies or substantial portions of the Software. 
 > > + * 
 > > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
 > > + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
 > > + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 
 > > + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
 > > + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
 > > + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 
 > > + * THE SOFTWARE. 
 > > + */ 
 > > + 
 > > +#ifndef HW_SHAKTI_UART_H 
 > > +#define HW_SHAKTI_UART_H 
 > > + 
 > > +#include "hw/sysbus.h" 
 > > +#include "chardev/char-fe.h" 
 > > + 
 > > +#define SHAKTI_UART_BAUD        0x00 
 > > +#define SHAKTI_UART_TX          0x04 
 > > +#define SHAKTI_UART_RX          0x08 
 > > +#define SHAKTI_UART_STATUS      0x0C 
 > > +#define SHAKTI_UART_DELAY       0x10 
 > > +#define SHAKTI_UART_CONTROL     0x14 
 > > +#define SHAKTI_UART_INT_EN      0x18 
 > > +#define SHAKTI_UART_IQ_CYCLES   0x1C 
 > > +#define SHAKTI_UART_RX_THRES    0x20 
 > > + 
 > > +#define SHAKTI_UART_STATUS_TX_EMPTY     (1 << 0) 
 > > +#define SHAKTI_UART_STATUS_TX_FULL      (1 << 1) 
 > > +#define SHAKTI_UART_STATUS_RX_NOT_EMPTY (1 << 2) 
 > > +#define SHAKTI_UART_STATUS_RX_FULL      (1 << 3) 
 > > +/* 9600 8N1 is the default setting */ 
 > > +/* Reg value = (50000000 Hz)/(16 * 9600)*/ 
 > > +#define SHAKTI_UART_BAUD_DEFAULT    0x0145 
 > > +#define SHAKTI_UART_CONTROL_DEFAULT 0x0100 
 > > + 
 > > +#define TYPE_SHAKTI_UART "shakti-uart" 
 > > +#define SHAKTI_UART(obj) \ 
 > > +    OBJECT_CHECK(ShaktiUartState, (obj), TYPE_SHAKTI_UART) 
 > > + 
 > > +typedef struct { 
 > > +    /* <private> */ 
 > > +    SysBusDevice parent_obj; 
 > > + 
 > > +    /* <public> */ 
 > > +    MemoryRegion mmio; 
 > > + 
 > > +    uint32_t uart_baud; 
 > > +    uint32_t uart_tx; 
 > > +    uint32_t uart_rx; 
 > > +    uint32_t uart_status; 
 > > +    uint32_t uart_delay; 
 > > +    uint32_t uart_control; 
 > > +    uint32_t uart_interrupt; 
 > > +    uint32_t uart_iq_cycles; 
 > > +    uint32_t uart_rx_threshold; 
 > > + 
 > > +    CharBackend chr; 
 > > +} ShaktiUartState; 
 > > + 
 > > +#endif /* HW_SHAKTI_UART_H */ 
 > > -- 
 > > 2.25.1 
 > > 
 > > 
 > > 
 >
diff mbox series

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index 9f71c4cc3f..be084865db 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1385,7 +1385,9 @@  M: Vijai Kumar K <vijai@behindbytes.com>
 L: qemu-riscv@nongnu.org
 S: Supported
 F: hw/riscv/shakti_c.c
+F: hw/char/shakti_uart.c
 F: include/hw/riscv/shakti_c.h
+F: include/hw/char/shakti_uart.h
 
 SiFive Machines
 M: Alistair Francis <Alistair.Francis@wdc.com>
diff --git a/hw/char/meson.build b/hw/char/meson.build
index 7ba38dbd96..61c43d4b51 100644
--- a/hw/char/meson.build
+++ b/hw/char/meson.build
@@ -19,6 +19,7 @@  softmmu_ss.add(when: 'CONFIG_SERIAL', if_true: files('serial.c'))
 softmmu_ss.add(when: 'CONFIG_SERIAL_ISA', if_true: files('serial-isa.c'))
 softmmu_ss.add(when: 'CONFIG_SERIAL_PCI', if_true: files('serial-pci.c'))
 softmmu_ss.add(when: 'CONFIG_SERIAL_PCI_MULTI', if_true: files('serial-pci-multi.c'))
+softmmu_ss.add(when: 'CONFIG_SHAKTI', if_true: files('shakti_uart.c'))
 softmmu_ss.add(when: 'CONFIG_VIRTIO_SERIAL', if_true: files('virtio-console.c'))
 softmmu_ss.add(when: 'CONFIG_XEN', if_true: files('xen_console.c'))
 softmmu_ss.add(when: 'CONFIG_XILINX', if_true: files('xilinx_uartlite.c'))
diff --git a/hw/char/shakti_uart.c b/hw/char/shakti_uart.c
new file mode 100644
index 0000000000..e1c72e8747
--- /dev/null
+++ b/hw/char/shakti_uart.c
@@ -0,0 +1,204 @@ 
+/*
+ * SHAKTI UART
+ *
+ * Copyright (c) 2021 Vijai Kumar K <vijai@behindbytes.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/char/shakti_uart.h"
+#include "hw/qdev-properties.h"
+#include "hw/qdev-properties-system.h"
+#include "qemu/log.h"
+
+#define DEBUG_SHAKTI_UART 0
+#define DPRINTF(fmt, args...) \
+    do { \
+        if (DEBUG_SHAKTI_UART) { \
+            fprintf(stderr, "[%s]%s: " fmt , TYPE_SHAKTI_UART, \
+                                             __func__, ##args); \
+        } \
+    } while (0)
+
+static uint64_t shakti_uart_read(void *opaque, hwaddr addr, unsigned size)
+{
+    ShaktiUartState *s = opaque;
+    uint64_t retvalue = 0;
+
+    switch (addr) {
+    case SHAKTI_UART_BAUD:
+        return s->uart_baud;
+        break;
+    case SHAKTI_UART_RX:
+        retvalue = s->uart_rx;
+        qemu_chr_fe_accept_input(&s->chr);
+        s->uart_status &= ~SHAKTI_UART_STATUS_RX_NOT_EMPTY;
+        return retvalue;
+        break;
+    case SHAKTI_UART_STATUS:
+        DPRINTF("uart_status: value = 0x%x)\n", s->uart_status);
+        return s->uart_status;
+        break;
+    case SHAKTI_UART_DELAY:
+        return s->uart_delay;
+        break;
+    case SHAKTI_UART_CONTROL:
+        return s->uart_control;
+        break;
+    case SHAKTI_UART_INT_EN:
+        return s->uart_interrupt;
+        break;
+    case SHAKTI_UART_IQ_CYCLES:
+        return s->uart_iq_cycles;
+        break;
+    case SHAKTI_UART_RX_THRES:
+        return s->uart_rx_threshold;
+        break;
+    default:
+        /* Also handles TX REG which is write only */
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, addr);
+    }
+
+    return 0;
+}
+
+static void shakti_uart_write(void *opaque, hwaddr addr,
+                              uint64_t data, unsigned size)
+{
+    ShaktiUartState *s = opaque;
+    uint32_t value = data;
+    uint8_t ch;
+
+    switch (addr) {
+    case SHAKTI_UART_BAUD:
+        s->uart_baud = value;
+        break;
+    case SHAKTI_UART_TX:
+        ch = value;
+        qemu_chr_fe_write_all(&s->chr, &ch, 1);
+        s->uart_status &= ~SHAKTI_UART_STATUS_TX_FULL;
+        break;
+    case SHAKTI_UART_STATUS:
+        s->uart_status = value;
+        break;
+    case SHAKTI_UART_DELAY:
+        s->uart_delay = value;
+        break;
+    case SHAKTI_UART_CONTROL:
+        s->uart_control = value;
+        break;
+    case SHAKTI_UART_INT_EN:
+        s->uart_interrupt = value;
+        break;
+    case SHAKTI_UART_IQ_CYCLES:
+        s->uart_iq_cycles = value;
+        break;
+    case SHAKTI_UART_RX_THRES:
+        s->uart_rx_threshold = value;
+        break;
+    default:
+        /* Also handles TX REG which is write only */
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, addr);
+    }
+}
+
+static const MemoryRegionOps shakti_uart_ops = {
+    .read = shakti_uart_read,
+    .write = shakti_uart_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .impl = {.min_access_size = 1, .max_access_size = 4},
+    .valid = {.min_access_size = 1, .max_access_size = 4},
+};
+
+static void shakti_uart_reset(DeviceState *dev)
+{
+    ShaktiUartState *s = SHAKTI_UART(dev);
+
+    s->uart_baud = SHAKTI_UART_BAUD_DEFAULT;
+    s->uart_tx = 0x0;
+    s->uart_rx = 0x0;
+    s->uart_status = 0x0000;
+    s->uart_delay = 0x0000;
+    s->uart_control = SHAKTI_UART_CONTROL_DEFAULT;
+    s->uart_interrupt = 0x0000;
+    s->uart_iq_cycles = 0x00;
+    s->uart_rx_threshold = 0x00;
+}
+
+static int shakti_uart_can_receive(void *opaque)
+{
+    return 1;
+}
+
+static void shakti_uart_receive(void *opaque, const uint8_t *buf, int size)
+{
+    ShaktiUartState *s = opaque;
+
+    s->uart_rx = *buf;
+    s->uart_status |= SHAKTI_UART_STATUS_RX_NOT_EMPTY;
+}
+
+static void shakti_uart_realize(DeviceState *dev, Error **errp)
+{
+    ShaktiUartState *sus = SHAKTI_UART(dev);
+    qemu_chr_fe_set_handlers(&sus->chr, shakti_uart_can_receive,
+                             shakti_uart_receive, NULL, NULL, sus, NULL, true);
+}
+
+static void shakti_uart_instance_init(Object *obj)
+{
+    ShaktiUartState *sus = SHAKTI_UART(obj);
+    memory_region_init_io(&sus->mmio,
+                          obj,
+                          &shakti_uart_ops,
+                          sus,
+                          TYPE_SHAKTI_UART,
+                          0x1000);
+    sysbus_init_mmio(SYS_BUS_DEVICE(obj), &sus->mmio);
+}
+
+static Property shakti_uart_properties[] = {
+    DEFINE_PROP_CHR("chardev", ShaktiUartState, chr),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void shakti_uart_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    dc->reset = shakti_uart_reset;
+    dc->realize = shakti_uart_realize;
+    device_class_set_props(dc, shakti_uart_properties);
+}
+
+static const TypeInfo shakti_uart_info = {
+    .name = TYPE_SHAKTI_UART,
+    .parent = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(ShaktiUartState),
+    .class_init = shakti_uart_class_init,
+    .instance_init = shakti_uart_instance_init,
+};
+
+static void shakti_uart_register_types(void)
+{
+    type_register_static(&shakti_uart_info);
+}
+type_init(shakti_uart_register_types)
diff --git a/hw/char/trace-events b/hw/char/trace-events
index 81026f6612..54aeeb899c 100644
--- a/hw/char/trace-events
+++ b/hw/char/trace-events
@@ -80,6 +80,10 @@  cmsdk_apb_uart_set_params(int speed) "CMSDK APB UART: params set to %d 8N1"
 nrf51_uart_read(uint64_t addr, uint64_t r, unsigned int size) "addr 0x%" PRIx64 " value 0x%" PRIx64 " size %u"
 nrf51_uart_write(uint64_t addr, uint64_t value, unsigned int size) "addr 0x%" PRIx64 " value 0x%" PRIx64 " size %u"
 
+# shakti_uart.c
+shakti_uart_read(uint64_t addr, uint16_t r, unsigned int size) "addr 0x%" PRIx64 " value 0x%" PRIx16 " size %u"
+shakti_uart_write(uint64_t addr, uint64_t value, unsigned int size) "addr 0x%" PRIx64 " value 0x%" PRIx64 " size %u"
+
 # exynos4210_uart.c
 exynos_uart_dmabusy(uint32_t channel) "UART%d: DMA busy (Rx buffer empty)"
 exynos_uart_dmaready(uint32_t channel) "UART%d: DMA ready"
diff --git a/include/hw/char/shakti_uart.h b/include/hw/char/shakti_uart.h
new file mode 100644
index 0000000000..526c408233
--- /dev/null
+++ b/include/hw/char/shakti_uart.h
@@ -0,0 +1,74 @@ 
+/*
+ * SHAKTI UART
+ *
+ * Copyright (c) 2021 Vijai Kumar K <vijai@behindbytes.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef HW_SHAKTI_UART_H
+#define HW_SHAKTI_UART_H
+
+#include "hw/sysbus.h"
+#include "chardev/char-fe.h"
+
+#define SHAKTI_UART_BAUD        0x00
+#define SHAKTI_UART_TX          0x04
+#define SHAKTI_UART_RX          0x08
+#define SHAKTI_UART_STATUS      0x0C
+#define SHAKTI_UART_DELAY       0x10
+#define SHAKTI_UART_CONTROL     0x14
+#define SHAKTI_UART_INT_EN      0x18
+#define SHAKTI_UART_IQ_CYCLES   0x1C
+#define SHAKTI_UART_RX_THRES    0x20
+
+#define SHAKTI_UART_STATUS_TX_EMPTY     (1 << 0)
+#define SHAKTI_UART_STATUS_TX_FULL      (1 << 1)
+#define SHAKTI_UART_STATUS_RX_NOT_EMPTY (1 << 2)
+#define SHAKTI_UART_STATUS_RX_FULL      (1 << 3)
+/* 9600 8N1 is the default setting */
+/* Reg value = (50000000 Hz)/(16 * 9600)*/
+#define SHAKTI_UART_BAUD_DEFAULT    0x0145
+#define SHAKTI_UART_CONTROL_DEFAULT 0x0100
+
+#define TYPE_SHAKTI_UART "shakti-uart"
+#define SHAKTI_UART(obj) \
+    OBJECT_CHECK(ShaktiUartState, (obj), TYPE_SHAKTI_UART)
+
+typedef struct {
+    /* <private> */
+    SysBusDevice parent_obj;
+
+    /* <public> */
+    MemoryRegion mmio;
+
+    uint32_t uart_baud;
+    uint32_t uart_tx;
+    uint32_t uart_rx;
+    uint32_t uart_status;
+    uint32_t uart_delay;
+    uint32_t uart_control;
+    uint32_t uart_interrupt;
+    uint32_t uart_iq_cycles;
+    uint32_t uart_rx_threshold;
+
+    CharBackend chr;
+} ShaktiUartState;
+
+#endif /* HW_SHAKTI_UART_H */