[1/3] hw/display : Add device DM163

This device implements the IM120417002 colors shield v1.1 for Arduino
(which relies on the DM163 8x3-channel led driving logic) and features
a simple display of an 8x8 RGB matrix. The columns of the matrix are
driven by the DM163 and the rows are driven externally.

Signed-off-by: Arnaud Minier <arnaud.minier@telecom-paris.fr>
Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>
---
 hw/display/Kconfig         |   3 +
 hw/display/dm163.c         | 307 +++++++++++++++++++++++++++++++++++++
 hw/display/meson.build     |   1 +
 hw/display/trace-events    |  13 ++
 include/hw/display/dm163.h |  57 +++++++
 5 files changed, 381 insertions(+)
 create mode 100644 hw/display/dm163.c
 create mode 100644 include/hw/display/dm163.h

On Sat, Jan 27, 2024 at 5:38 AM Inès Varhol
<ines.varhol@telecom-paris.fr> wrote:
>
> This device implements the IM120417002 colors shield v1.1 for Arduino
> (which relies on the DM163 8x3-channel led driving logic) and features
> a simple display of an 8x8 RGB matrix. The columns of the matrix are
> driven by the DM163 and the rows are driven externally.
>
> Signed-off-by: Arnaud Minier <arnaud.minier@telecom-paris.fr>
> Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>

Acked-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>  hw/display/Kconfig         |   3 +
>  hw/display/dm163.c         | 307 +++++++++++++++++++++++++++++++++++++
>  hw/display/meson.build     |   1 +
>  hw/display/trace-events    |  13 ++
>  include/hw/display/dm163.h |  57 +++++++
>  5 files changed, 381 insertions(+)
>  create mode 100644 hw/display/dm163.c
>  create mode 100644 include/hw/display/dm163.h
>
> diff --git a/hw/display/Kconfig b/hw/display/Kconfig
> index 1aafe1923d..4dbfc6e7af 100644
> --- a/hw/display/Kconfig
> +++ b/hw/display/Kconfig
> @@ -139,3 +139,6 @@ config XLNX_DISPLAYPORT
>      bool
>      # defaults to "N", enabled by specific boards
>      depends on PIXMAN
> +
> +config DM163
> +    bool
> diff --git a/hw/display/dm163.c b/hw/display/dm163.c
> new file mode 100644
> index 0000000000..565fc84ddf
> --- /dev/null
> +++ b/hw/display/dm163.c
> @@ -0,0 +1,307 @@
> +/*
> + * QEMU DM163 8x3-channel constant current led driver
> + * driving columns of associated 8x8 RGB matrix.
> + *
> + * Copyright (C) 2024 Samuel Tardieu <sam@rfc1149.net>
> + * Copyright (C) 2024 Arnaud Minier <arnaud.minier@telecom-paris.fr>
> + * Copyright (C) 2024 Inès Varhol <ines.varhol@telecom-paris.fr>
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +
> +/*
> + * The reference used for the DM163 is the following :
> + * http://www.siti.com.tw/product/spec/LED/DM163.pdf
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qapi/error.h"
> +#include "migration/vmstate.h"
> +#include "hw/irq.h"
> +#include "hw/qdev-properties.h"
> +#include "hw/display/dm163.h"
> +#include "ui/console.h"
> +#include "trace.h"
> +
> +#define LED_SQUARE_SIZE 100
> +/* Number of frames a row stays visible after being turned off. */
> +#define ROW_PERSISTANCE 2
> +
> +static const VMStateDescription vmstate_dm163 = {
> +    .name = TYPE_DM163,
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .fields = (const VMStateField[]) {
> +        VMSTATE_UINT8(activated_rows, DM163State),
> +        VMSTATE_UINT64_ARRAY(bank0_shift_register, DM163State, 3),
> +        VMSTATE_UINT64_ARRAY(bank1_shift_register, DM163State, 3),
> +        VMSTATE_UINT16_ARRAY(latched_outputs, DM163State, DM163_NUM_LEDS),
> +        VMSTATE_UINT16_ARRAY(outputs, DM163State, DM163_NUM_LEDS),
> +        VMSTATE_UINT8(dck, DM163State),
> +        VMSTATE_UINT8(en_b, DM163State),
> +        VMSTATE_UINT8(lat_b, DM163State),
> +        VMSTATE_UINT8(rst_b, DM163State),
> +        VMSTATE_UINT8(selbk, DM163State),
> +        VMSTATE_UINT8(sin, DM163State),
> +        VMSTATE_UINT32_2DARRAY(buffer, DM163State,
> +            COLOR_BUFFER_SIZE + 1, RGB_MATRIX_NUM_COLS),
> +        VMSTATE_UINT8(last_buffer_idx, DM163State),
> +        VMSTATE_UINT8_ARRAY(buffer_idx_of_row, DM163State, RGB_MATRIX_NUM_ROWS),
> +        VMSTATE_UINT8_ARRAY(age_of_row, DM163State, RGB_MATRIX_NUM_ROWS),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +static void dm163_reset_hold(Object *obj)
> +{
> +    DM163State *s = DM163(obj);
> +
> +    /* Reset only stops the PWM. */
> +    memset(s->outputs, 0, sizeof(s->outputs));
> +
> +    /* The last row of the buffer stores a turned off row */
> +    memset(s->buffer[COLOR_BUFFER_SIZE], 0, sizeof(s->buffer[0]));
> +}
> +
> +static void dm163_dck_gpio_handler(void *opaque, int line, int new_state)
> +{
> +    DM163State *s = DM163(opaque);
> +
> +    if (new_state && !s->dck) {
> +        /*
> +         * On raising dck, sample selbk to get the bank to use, and
> +         * sample sin for the bit to enter into the bank shift buffer.
> +         */
> +        uint64_t *sb =
> +            s->selbk ? s->bank1_shift_register : s->bank0_shift_register;
> +        /* Output the outgoing bit on sout */
> +        const bool sout = (s->selbk ? sb[2] & MAKE_64BIT_MASK(63, 1) :
> +                           sb[2] & MAKE_64BIT_MASK(15, 1)) != 0;
> +        qemu_set_irq(s->sout, sout);
> +        /* Enter sin into the shift buffer */
> +        sb[2] = (sb[2] << 1) | ((sb[1] >> 63) & 1);
> +        sb[1] = (sb[1] << 1) | ((sb[0] >> 63) & 1);
> +        sb[0] = (sb[0] << 1) | s->sin;
> +    }
> +
> +    s->dck = new_state;
> +    trace_dm163_dck(new_state);
> +}
> +
> +static void dm163_propagate_outputs(DM163State *s)
> +{
> +    s->last_buffer_idx = (s->last_buffer_idx + 1) % COLOR_BUFFER_SIZE;
> +    /* Values are output when reset and enable are both high. */
> +    if (s->rst_b && !s->en_b) {
> +        memcpy(s->outputs, s->latched_outputs, sizeof(s->outputs));
> +    } else {
> +        memset(s->outputs, 0, sizeof(s->outputs));
> +    }
> +    for (unsigned x = 0; x < RGB_MATRIX_NUM_COLS; x++) {
> +        trace_dm163_channels(3 * x, (uint8_t)(s->outputs[3 * x] >> 6));
> +        trace_dm163_channels(3 * x + 1, (uint8_t)(s->outputs[3 * x + 1] >> 6));
> +        trace_dm163_channels(3 * x + 2, (uint8_t)(s->outputs[3 * x + 2] >> 6));
> +        s->buffer[s->last_buffer_idx][x] =
> +            (s->outputs[3 * x + 2] >> 6) |
> +            ((s->outputs[3 * x + 1] << 2) & 0xFF00) |
> +            (((uint32_t)s->outputs[3 * x] << 10) & 0xFF0000);
> +    }
> +    for (unsigned row = 0; row < RGB_MATRIX_NUM_ROWS; row++) {
> +        if (s->activated_rows & (1 << row)) {
> +            s->buffer_idx_of_row[row] = s->last_buffer_idx;
> +        }
> +    }
> +}
> +
> +static void dm163_en_b_gpio_handler(void *opaque, int line, int new_state)
> +{
> +    DM163State *s = DM163(opaque);
> +
> +    s->en_b = new_state;
> +    dm163_propagate_outputs(s);
> +    trace_dm163_en_b(new_state);
> +}
> +
> +static inline uint8_t dm163_bank0(const DM163State *s, uint8_t led)
> +{
> +    /*
> +     * Bank 1 uses 6 bits per led, so a value may be stored accross
> +     * two uint64_t entries.
> +     */
> +    const uint8_t low_bit = 6 * led;
> +    const uint8_t low_word = low_bit / 64;
> +    const uint8_t high_word = (low_bit + 5) / 64;
> +    const uint8_t low_shift = low_bit % 64;
> +
> +    if (low_word == high_word) {
> +        /* Simple case: the value belongs to one entry. */
> +        return (s->bank0_shift_register[low_word] &
> +                MAKE_64BIT_MASK(low_shift, 6)) >> low_shift;
> +    }
> +
> +    const uint8_t bits_in_low_word = 64 - low_shift;
> +    const uint8_t bits_in_high_word = 6 - bits_in_low_word;
> +    return ((s->bank0_shift_register[low_word] &
> +             MAKE_64BIT_MASK(low_shift, bits_in_low_word)) >>
> +            low_shift) |
> +           ((s->bank0_shift_register[high_word] &
> +             MAKE_64BIT_MASK(0, bits_in_high_word))
> +         << bits_in_low_word);
> +}
> +
> +static inline uint8_t dm163_bank1(const DM163State *s, uint8_t led)
> +{
> +    const uint64_t entry = s->bank1_shift_register[led / 8];
> +    const unsigned shift = 8 * (led % 8);
> +    return (entry & MAKE_64BIT_MASK(shift, 8)) >> shift;
> +}
> +
> +static void dm163_lat_b_gpio_handler(void *opaque, int line, int new_state)
> +{
> +    DM163State *s = DM163(opaque);
> +
> +    if (s->lat_b && !new_state) {
> +        for (int led = 0; led < DM163_NUM_LEDS; led++) {
> +            s->latched_outputs[led] = dm163_bank0(s, led) * dm163_bank1(s, led);
> +        }
> +        dm163_propagate_outputs(s);
> +    }
> +
> +    s->lat_b = new_state;
> +    trace_dm163_lat_b(new_state);
> +}
> +
> +static void dm163_rst_b_gpio_handler(void *opaque, int line, int new_state)
> +{
> +    DM163State *s = DM163(opaque);
> +
> +    s->rst_b = new_state;
> +    dm163_propagate_outputs(s);
> +    trace_dm163_rst_b(new_state);
> +}
> +
> +static void dm163_selbk_gpio_handler(void *opaque, int line, int new_state)
> +{
> +    DM163State *s = DM163(opaque);
> +
> +    s->selbk = new_state;
> +    trace_dm163_selbk(new_state);
> +}
> +
> +static void dm163_sin_gpio_handler(void *opaque, int line, int new_state)
> +{
> +    DM163State *s = DM163(opaque);
> +
> +    s->sin = new_state;
> +    trace_dm163_sin(new_state);
> +}
> +
> +static void dm163_rows_gpio_handler(void *opaque, int line, int new_state)
> +{
> +    DM163State *s = DM163(opaque);
> +
> +    if (new_state) {
> +        s->activated_rows |= (1 << line);
> +        s->buffer_idx_of_row[line] = s->last_buffer_idx;
> +        s->age_of_row[line] = 0;
> +    } else {
> +        s->activated_rows &= ~(1 << line);
> +        s->age_of_row[line] = ROW_PERSISTANCE;
> +    }
> +    trace_dm163_activated_rows(s->activated_rows);
> +}
> +
> +static void dm163_invalidate_display(void *opaque)
> +{
> +}
> +
> +static void dm163_update_display(void *opaque)
> +{
> +    DM163State *s = (DM163State *)opaque;
> +    DisplaySurface *surface = qemu_console_surface(s->console);
> +    uint32_t *dest;
> +    unsigned bits_ppi = surface_bits_per_pixel(surface);
> +
> +    trace_dm163_bits_ppi(bits_ppi);
> +    g_assert((bits_ppi == 32));
> +    dest = surface_data(surface);
> +    for (unsigned y = 0; y < RGB_MATRIX_NUM_ROWS; y++) {
> +        for (unsigned _ = 0; _ < LED_SQUARE_SIZE; _++) {
> +            for (int x = RGB_MATRIX_NUM_COLS * LED_SQUARE_SIZE - 1; x >= 0; x--) {
> +                *dest++ = s->buffer[s->buffer_idx_of_row[y]][x / LED_SQUARE_SIZE];
> +            }
> +        }
> +        if (s->age_of_row[y]) {
> +            s->age_of_row[y]--;
> +            if (!s->age_of_row[y]) {
> +                /*
> +                 * If the ROW_PERSISTANCE delay is up,
> +                 * the row is turned off.
> +                 * (s->buffer[COLOR_BUFFER] is filled with 0)
> +                 */
> +                s->buffer_idx_of_row[y] = COLOR_BUFFER_SIZE;
> +            }
> +        }
> +    }
> +    /*
> +     * Ideally set the refresh rate so that the row persistance
> +     * doesn't need to be changed.
> +     *
> +     * Currently `dpy_ui_info_supported(s->console)` returns false
> +     * which makes it impossible to get or set UIInfo.
> +     *
> +     * if (dpy_ui_info_supported(s->console)) {
> +     *     trace_dm163_refresh_rate(dpy_get_ui_info(s->console)->refresh_rate);
> +     * } else {
> +     *     trace_dm163_refresh_rate(0);
> +     * }
> +     */
> +    dpy_gfx_update(s->console, 0, 0, RGB_MATRIX_NUM_COLS * LED_SQUARE_SIZE,
> +                   RGB_MATRIX_NUM_ROWS * LED_SQUARE_SIZE);
> +}
> +
> +static const GraphicHwOps dm163_ops = {
> +    .invalidate  = dm163_invalidate_display,
> +    .gfx_update  = dm163_update_display,
> +};
> +
> +static void dm163_realize(DeviceState *dev, Error **errp)
> +{
> +    DM163State *s = DM163(dev);
> +
> +    qdev_init_gpio_in(dev, dm163_rows_gpio_handler, 8);
> +    qdev_init_gpio_in(dev, dm163_sin_gpio_handler, 1);
> +    qdev_init_gpio_in(dev, dm163_dck_gpio_handler, 1);
> +    qdev_init_gpio_in(dev, dm163_rst_b_gpio_handler, 1);
> +    qdev_init_gpio_in(dev, dm163_lat_b_gpio_handler, 1);
> +    qdev_init_gpio_in(dev, dm163_selbk_gpio_handler, 1);
> +    qdev_init_gpio_in(dev, dm163_en_b_gpio_handler, 1);
> +    qdev_init_gpio_out_named(dev, &s->sout, "sout", 1);
> +
> +    s->console = graphic_console_init(dev, 0, &dm163_ops, s);
> +    qemu_console_resize(s->console, RGB_MATRIX_NUM_COLS * LED_SQUARE_SIZE,
> +                        RGB_MATRIX_NUM_ROWS * LED_SQUARE_SIZE);
> +}
> +
> +static void dm163_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +    ResettableClass *rc = RESETTABLE_CLASS(klass);
> +
> +    dc->desc = "DM163";
> +    dc->vmsd = &vmstate_dm163;
> +    dc->realize = dm163_realize;
> +    rc->phases.hold = dm163_reset_hold;
> +    set_bit(DEVICE_CATEGORY_DISPLAY, dc->categories);
> +}
> +
> +static const TypeInfo dm163_types[] = {
> +    {
> +        .name = TYPE_DM163,
> +        .parent = TYPE_DEVICE,
> +        .instance_size = sizeof(DM163State),
> +        .class_init = dm163_class_init
> +    }
> +};
> +
> +DEFINE_TYPES(dm163_types)
> diff --git a/hw/display/meson.build b/hw/display/meson.build
> index f93a69f70f..71e489308e 100644
> --- a/hw/display/meson.build
> +++ b/hw/display/meson.build
> @@ -38,6 +38,7 @@ system_ss.add(when: 'CONFIG_NEXTCUBE', if_true: files('next-fb.c'))
>
>  system_ss.add(when: 'CONFIG_VGA', if_true: files('vga.c'))
>  system_ss.add(when: 'CONFIG_VIRTIO', if_true: files('virtio-dmabuf.c'))
> +system_ss.add(when: 'CONFIG_DM163', if_true: files('dm163.c'))
>
>  if (config_all_devices.has_key('CONFIG_VGA_CIRRUS') or
>      config_all_devices.has_key('CONFIG_VGA_PCI') or
> diff --git a/hw/display/trace-events b/hw/display/trace-events
> index 2336a0ca15..444b014d6e 100644
> --- a/hw/display/trace-events
> +++ b/hw/display/trace-events
> @@ -177,3 +177,16 @@ macfb_ctrl_write(uint64_t addr, uint64_t value, unsigned int size) "addr 0x%"PRI
>  macfb_sense_read(uint32_t value) "video sense: 0x%"PRIx32
>  macfb_sense_write(uint32_t value) "video sense: 0x%"PRIx32
>  macfb_update_mode(uint32_t width, uint32_t height, uint8_t depth) "setting mode to width %"PRId32 " height %"PRId32 " size %d"
> +
> +# dm163.c
> +dm163_dck(int new_state) "dck : %d"
> +dm163_en_b(int new_state) "en_b : %d"
> +dm163_rst_b(int new_state) "rst_b : %d"
> +dm163_lat_b(int new_state) "lat_b : %d"
> +dm163_sin(int new_state) "sin : %d"
> +dm163_selbk(int new_state) "selbk : %d"
> +dm163_activated_rows(int new_state) "Activated rows : 0x%" PRIx32 ""
> +dm163_bits_ppi(unsigned dest_width) "dest_width : %u"
> +dm163_leds(int led, uint32_t value) "led %d: 0x%x"
> +dm163_channels(int channel, uint8_t value) "channel %d: 0x%x"
> +dm163_refresh_rate(uint32_t rr) "refresh rate %d"
> diff --git a/include/hw/display/dm163.h b/include/hw/display/dm163.h
> new file mode 100644
> index 0000000000..aa775e51e1
> --- /dev/null
> +++ b/include/hw/display/dm163.h
> @@ -0,0 +1,57 @@
> +/*
> + * QEMU DM163 8x3-channel constant current led driver
> + * driving columns of associated 8x8 RGB matrix.
> + *
> + * Copyright (C) 2024 Samuel Tardieu <sam@rfc1149.net>
> + * Copyright (C) 2024 Arnaud Minier <arnaud.minier@telecom-paris.fr>
> + * Copyright (C) 2024 Inès Varhol <ines.varhol@telecom-paris.fr>
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +
> +#ifndef HW_DISPLAY_DM163_H
> +#define HW_DISPLAY_DM163_H
> +
> +#include "qom/object.h"
> +#include "hw/qdev-core.h"
> +
> +#define TYPE_DM163 "dm163"
> +OBJECT_DECLARE_SIMPLE_TYPE(DM163State, DM163);
> +
> +#define DM163_NUM_LEDS 24
> +#define RGB_MATRIX_NUM_ROWS 8
> +#define RGB_MATRIX_NUM_COLS (DM163_NUM_LEDS / 3)
> +#define COLOR_BUFFER_SIZE RGB_MATRIX_NUM_ROWS
> +
> +typedef struct DM163State {
> +    DeviceState parent_obj;
> +
> +    /* DM163 driver */
> +    uint64_t bank0_shift_register[3];
> +    uint64_t bank1_shift_register[3];
> +    uint16_t latched_outputs[DM163_NUM_LEDS];
> +    uint16_t outputs[DM163_NUM_LEDS];
> +    qemu_irq sout;
> +
> +    uint8_t dck;
> +    uint8_t en_b;
> +    uint8_t lat_b;
> +    uint8_t rst_b;
> +    uint8_t selbk;
> +    uint8_t sin;
> +
> +    /* IM120417002 colors shield */
> +    uint8_t activated_rows;
> +
> +    /* 8x8 RGB matrix */
> +    QemuConsole *console;
> +    /* Rows currently being displayed on the matrix. */
> +    /* The last row is filled with 0 (turned off row) */
> +    uint32_t buffer[COLOR_BUFFER_SIZE + 1][RGB_MATRIX_NUM_COLS];
> +    uint8_t last_buffer_idx;
> +    uint8_t buffer_idx_of_row[RGB_MATRIX_NUM_ROWS];
> +    /* Used to simulate retinal persistance of rows */
> +    uint8_t age_of_row[RGB_MATRIX_NUM_ROWS];
> +} DM163State;
> +
> +#endif /* HW_DISPLAY_DM163_H */
> --
> 2.43.0
>
>