Re: [RFC Patch 4/5] hw/display: Allwinner A10 LCDC emulation

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

+Gerd & Marc-André for the ui/fb parts.

On 5/9/23 22:14, Strahinja Jankovic wrote:
> This patch adds support for Allwinner A10 LCD controller.
> Current emulation supports only RGB32 colorspace and interacts with
> DEBE0 to obtain framebuffer address and screen size.
> 
> Signed-off-by: Strahinja Jankovic <strahinja.p.jankovic@gmail.com>
> ---
>   hw/arm/allwinner-a10.c                  |  10 +
>   hw/display/allwinner-a10-lcdc.c         | 275 ++++++++++++++++++++++++
>   hw/display/meson.build                  |   1 +
>   hw/display/trace-events                 |   5 +
>   include/hw/arm/allwinner-a10.h          |   2 +
>   include/hw/display/allwinner-a10-lcdc.h |  77 +++++++
>   6 files changed, 370 insertions(+)
>   create mode 100644 hw/display/allwinner-a10-lcdc.c
>   create mode 100644 include/hw/display/allwinner-a10-lcdc.h
> 
> diff --git a/hw/arm/allwinner-a10.c b/hw/arm/allwinner-a10.c
> index 624e95af46..f93bc5266d 100644
> --- a/hw/arm/allwinner-a10.c
> +++ b/hw/arm/allwinner-a10.c
> @@ -41,6 +41,7 @@
>   #define AW_A10_WDT_BASE         0x01c20c90
>   #define AW_A10_RTC_BASE         0x01c20d00
>   #define AW_A10_I2C0_BASE        0x01c2ac00
> +#define AW_A10_LCDC0_BASE       0x01c0c000
>   #define AW_A10_HDMI_BASE        0x01c16000
>   #define AW_A10_GPU_BASE         0x01c40000
>   #define AW_A10_DE_BE0_BASE      0x01e60000
> @@ -101,6 +102,8 @@ static void aw_a10_init(Object *obj)
>   
>       object_initialize_child(obj, "hdmi", &s->hdmi, TYPE_AW_A10_HDMI);
>   
> +    object_initialize_child(obj, "lcd0", &s->lcd0, TYPE_AW_A10_LCDC);
> +
>       object_initialize_child(obj, "de_be0", &s->de_be0, TYPE_AW_A10_DEBE);
>   
>       object_initialize_child(obj, "mali400", &s->gpu, TYPE_AW_GPU);
> @@ -230,6 +233,13 @@ static void aw_a10_realize(DeviceState *dev, Error **errp)
>       sysbus_realize(SYS_BUS_DEVICE(&s->de_be0), &error_fatal);
>       sysbus_mmio_map(SYS_BUS_DEVICE(&s->de_be0), 0, AW_A10_DE_BE0_BASE);
>   
> +    /* LCD Controller */
> +    object_property_set_link(OBJECT(&s->lcd0), "debe",
> +                             OBJECT(&s->de_be0), &error_fatal);

IIUC you have LCDC polling DEBE for size update then invalidate,
shouldn't be the opposite, LCDC linked to DEBE and DEBE call the
LCDC invalidate handler on resize?

> +    sysbus_realize(SYS_BUS_DEVICE(&s->lcd0), &error_fatal);
> +    sysbus_mmio_map(SYS_BUS_DEVICE(&s->lcd0), 0, AW_A10_LCDC0_BASE);
> +    sysbus_connect_irq(SYS_BUS_DEVICE(&s->lcd0), 0, qdev_get_gpio_in(dev, 44));
> +
>       /* MALI GPU */
>       sysbus_realize(SYS_BUS_DEVICE(&s->gpu), &error_fatal);
>       sysbus_mmio_map(SYS_BUS_DEVICE(&s->gpu), 0, AW_A10_GPU_BASE);
> diff --git a/hw/display/allwinner-a10-lcdc.c b/hw/display/allwinner-a10-lcdc.c
> new file mode 100644
> index 0000000000..8367ac32be
> --- /dev/null
> +++ b/hw/display/allwinner-a10-lcdc.c
> @@ -0,0 +1,275 @@
> +/*
> + * Allwinner A10 LCD Control Module emulation
> + *
> + * Copyright (C) 2023 Strahinja Jankovic <strahinja.p.jankovic@gmail.com>
> + *
> + * This program is free software: you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation, either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that 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/units.h"
> +#include "hw/sysbus.h"
> +#include "migration/vmstate.h"
> +#include "qemu/log.h"
> +#include "hw/qdev-properties.h"
> +#include "qemu/module.h"
> +#include "hw/display/allwinner-a10-lcdc.h"
> +#include "hw/irq.h"
> +#include "ui/pixel_ops.h"
> +#include "trace.h"
> +#include "sysemu/dma.h"
> +#include "framebuffer.h"
> +
> +/* LCDC register offsets */
> +enum {
> +    REG_TCON_GCTL       = 0x0000, /* TCON Global control register */
> +    REG_TCON_GINT0      = 0x0004, /* TCON Global interrupt register 0 */
> +};
> +
> +/* TCON_GCTL register fields */
> +#define REG_TCON_GCTL_EN        (1 << 31)
> +
> +/* TCON_GINT0 register fields */
> +#define REG_TCON_GINT0_VB_INT_EN    (1 << 31)
> +#define REG_TCON_GINT0_VB_INT_FLAG  (1 << 14)
> +
> +#define REG_INDEX(offset)    (offset / sizeof(uint32_t))
> +
> +static void allwinner_a10_lcdc_tick(void *opaque)
> +{
> +    AwA10LcdcState *s = AW_A10_LCDC(opaque);
> +
> +    if (s->regs[REG_INDEX(REG_TCON_GINT0)] & REG_TCON_GINT0_VB_INT_EN) {
> +        s->regs[REG_INDEX(REG_TCON_GINT0)] |= REG_TCON_GINT0_VB_INT_FLAG;
> +        qemu_irq_raise(s->irq);
> +    }
> +}
> +
> +static uint64_t allwinner_a10_lcdc_read(void *opaque, hwaddr offset,
> +                                       unsigned size)
> +{
> +    AwA10LcdcState *s = AW_A10_LCDC(opaque);
> +    const uint32_t idx = REG_INDEX(offset);
> +    uint32_t val = s->regs[idx];
> +
> +    switch (offset) {
> +    case 0x800 ... AW_A10_LCDC_IOSIZE:
> +        qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
> +                  __func__, (uint32_t)offset);
> +        return 0;
> +    default:
> +        break;
> +    }
> +
> +    trace_allwinner_a10_lcdc_read(offset, val);
> +
> +    return val;
> +}
> +
> +static void allwinner_a10_lcdc_write(void *opaque, hwaddr offset,
> +                                   uint64_t val, unsigned size)
> +{
> +    AwA10LcdcState *s = AW_A10_LCDC(opaque);
> +    const uint32_t idx = REG_INDEX(offset);
> +
> +    switch (offset) {
> +    case REG_TCON_GCTL:
> +        s->is_enabled = !!REG_TCON_GCTL_EN;
> +        break;
> +    case REG_TCON_GINT0:
> +        if (0 == (val & REG_TCON_GINT0_VB_INT_FLAG)) {
> +            qemu_irq_lower(s->irq);
> +        }
> +        break;
> +    case 0x800 ... AW_A10_LCDC_IOSIZE:
> +        qemu_log_mask(LOG_GUEST_ERROR, "%s: out-of-bounds offset 0x%04x\n",
> +                  __func__, (uint32_t)offset);
> +        break;
> +    default:
> +        break;
> +    }
> +
> +    trace_allwinner_a10_lcdc_write(offset, (uint32_t)val);
> +
> +    s->regs[idx] = (uint32_t) val;
> +}
> +
> +static const MemoryRegionOps allwinner_a10_lcdc_ops = {
> +    .read = allwinner_a10_lcdc_read,
> +    .write = allwinner_a10_lcdc_write,
> +    .endianness = DEVICE_NATIVE_ENDIAN,
> +    .valid = {
> +        .min_access_size = 1,
> +        .max_access_size = 4,
> +    },
> +    .impl.min_access_size = 1,
> +};
> +
> +#define COPY_PIXEL(to, from) do { *(uint32_t *)to = from; to += 4; } while (0)
> +
> +static void draw_line(void *opaque, uint8_t *d, const uint8_t *src,
> +                      int width, int deststep)
> +{
> +    uint32_t data;
> +    unsigned int r, g, b;
> +    while (width > 0) {
> +        data = *(uint32_t *)src;
> +        b = data & 0xff;
> +        g = (data >> 8) & 0xff;
> +        r = (data >> 16) & 0xff;
> +        COPY_PIXEL(d, rgb_to_pixel32(r, g, b));
> +        width--;
> +        src += 4;
> +    }
> +}
> +
> +static void allwinner_a10_lcdc_invalidate_display(void *opaque)
> +{
> +    AwA10LcdcState *s = AW_A10_LCDC(opaque);
> +    qemu_console_resize(s->con, s->debe->width, s->debe->height);
> +    s->invalidate = 1;
> +}
> +
> +static void allwinner_a10_lcdc_update_display(void *opaque)
> +{
> +    AwA10LcdcState *s = AW_A10_LCDC(opaque);
> +    DisplaySurface *surface;
> +    int step, width, height, linesize, first = 0, last;
> +
> +    if (!s->is_enabled || !s->debe->ready) {
> +        return;
> +    }
> +
> +    width = s->debe->width;
> +    height = s->debe->height;
> +    step = width * (s->debe->bpp >> 3);
> +
> +    if (s->debe->invalidate) {
> +        allwinner_a10_lcdc_invalidate_display(opaque);
> +        s->debe->invalidate = false;
> +    }
> +
> +    surface = qemu_console_surface(s->con);
> +    linesize = surface_stride(surface);
> +
> +    if (s->invalidate) {
> +        framebuffer_update_memory_section(&s->fbsection,
> +                                    sysbus_address_space(SYS_BUS_DEVICE(s)),
> +                                    s->debe->framebuffer_offset,
> +                                    height, step);
> +    }
> +
> +    framebuffer_update_display(surface, &s->fbsection,
> +                               width, height,
> +                               step, linesize, 0,
> +                               s->invalidate,
> +                               draw_line, NULL,
> +                               &first, &last);
> +
> +    trace_allwinner_a10_draw(first, last, s->invalidate);
> +
> +    if (first >= 0) {
> +        dpy_gfx_update(s->con, 0, first, width, last - first + 1);
> +    }
> +    s->invalidate = 0;
> +
> +}
> +
> +static const GraphicHwOps allwinner_a10_lcdc_gfx_ops = {
> +    .invalidate  = allwinner_a10_lcdc_invalidate_display,
> +    .gfx_update  = allwinner_a10_lcdc_update_display,
> +};
> +
> +static void allwinner_a10_lcdc_reset_enter(Object *obj, ResetType type)
> +{
> +    AwA10LcdcState *s = AW_A10_LCDC(obj);
> +    s->invalidate = 1;
> +}
> +
> +static void allwinner_a10_lcdc_init(Object *obj)
> +{
> +    SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
> +    AwA10LcdcState *s = AW_A10_LCDC(obj);
> +
> +    /* Memory mapping */
> +    memory_region_init_io(&s->iomem, OBJECT(s), &allwinner_a10_lcdc_ops, s,
> +                          TYPE_AW_A10_LCDC, AW_A10_LCDC_IOSIZE);
> +    sysbus_init_mmio(sbd, &s->iomem);
> +    sysbus_init_irq(sbd, &s->irq);
> +    s->invalidate = 1;
> +    s->is_enabled = 0;
> +}
> +
> +static void allwinner_a10_lcdc_realize(DeviceState *dev, Error **errp)
> +{
> +    AwA10LcdcState *s = AW_A10_LCDC(dev);
> +
> +    s->timer = ptimer_init(allwinner_a10_lcdc_tick, s,
> +                           PTIMER_POLICY_NO_IMMEDIATE_TRIGGER |
> +                           PTIMER_POLICY_NO_IMMEDIATE_RELOAD |
> +                           PTIMER_POLICY_NO_COUNTER_ROUND_DOWN);
> +
> +    ptimer_transaction_begin(s->timer);
> +    /* Set to 60Hz */
> +    ptimer_set_freq(s->timer, 60);
> +    ptimer_set_limit(s->timer, 0x1, 1);
> +    ptimer_run(s->timer, 0);
> +    ptimer_transaction_commit(s->timer);
> +
> +    s->invalidate = 1;
> +    s->con = graphic_console_init(NULL, 0, &allwinner_a10_lcdc_gfx_ops, s);
> +    qemu_console_resize(s->con, s->debe->width, s->debe->height);
> +}
> +
> +static const VMStateDescription allwinner_a10_lcdc_vmstate = {
> +    .name = "allwinner-a10_lcdc",
> +    .version_id = 1,
> +    .minimum_version_id = 1,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_UINT32_ARRAY(regs, AwA10LcdcState, AW_A10_LCDC_REGS_NUM),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +static Property allwinner_a10_lcdc_properties[] = {
> +    DEFINE_PROP_LINK("debe", AwA10LcdcState, debe,
> +                     TYPE_AW_A10_DEBE, AwA10DEBEState *),
> +    DEFINE_PROP_END_OF_LIST(),
> +};
> +
> +static void allwinner_a10_lcdc_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +    ResettableClass *rc = RESETTABLE_CLASS(klass);
> +
> +    rc->phases.enter = allwinner_a10_lcdc_reset_enter;
> +    dc->vmsd = &allwinner_a10_lcdc_vmstate;
> +    dc->realize = allwinner_a10_lcdc_realize;
> +    device_class_set_props(dc, allwinner_a10_lcdc_properties);
> +}
> +
> +static const TypeInfo allwinner_a10_lcdc_info = {
> +    .name          = TYPE_AW_A10_LCDC,
> +    .parent        = TYPE_SYS_BUS_DEVICE,
> +    .instance_init = allwinner_a10_lcdc_init,
> +    .instance_size = sizeof(AwA10LcdcState),
> +    .class_init    = allwinner_a10_lcdc_class_init,
> +};
> +
> +static void allwinner_a10_lcdc_register(void)
> +{
> +    type_register_static(&allwinner_a10_lcdc_info);
> +}
> +
> +type_init(allwinner_a10_lcdc_register)
> diff --git a/hw/display/meson.build b/hw/display/meson.build
> index a3ef580b1c..e233026fdd 100644
> --- a/hw/display/meson.build
> +++ b/hw/display/meson.build
> @@ -40,6 +40,7 @@ system_ss.add(when: 'CONFIG_VGA', if_true: files('vga.c'))
>   
>   system_ss.add(when: 'CONFIG_ALLWINNER_A10', if_true: files('allwinner-a10-debe.c',
>                                                              'allwinner-a10-hdmi.c',
> +                                                           'allwinner-a10-lcdc.c',
>                                                              'allwinner-gpu.c'))
>   
>   if (config_all_devices.has_key('CONFIG_VGA_CIRRUS') or
> diff --git a/hw/display/trace-events b/hw/display/trace-events
> index 132b66fc81..4b962d6eda 100644
> --- a/hw/display/trace-events
> +++ b/hw/display/trace-events
> @@ -186,6 +186,11 @@ allwinner_a10_debe_write(uint64_t offset, uint64_t data) "Write: offset 0x%" PRI
>   allwinner_a10_hdmi_read(uint64_t offset, uint64_t data) "Read: offset 0x%" PRIx64 " data 0x%" PRIx64
>   allwinner_a10_hdmi_write(uint64_t offset, uint64_t data) "Write: offset 0x%" PRIx64 " data 0x%" PRIx64
>   
> +# allwinner-a10-lcdc.c
> +allwinner_a10_lcdc_read(uint64_t offset, uint64_t data) "Read: offset 0x%" PRIx64 " data 0x%" PRIx64
> +allwinner_a10_lcdc_write(uint64_t offset, uint64_t data) "Write: offset 0x%" PRIx64 " data 0x%" PRIx64
> +allwinner_a10_draw(uint32_t first, uint32_t last, uint32_t invalidate) "Draw: 0x%x, 0x%x, 0x%x"
> +
>   # allwinner-gpu.c
>   allwinner_gpu_read(uint64_t offset, uint64_t data) "Read: offset 0x%" PRIx64 " data 0x%" PRIx64
>   allwinner_gpu_write(uint64_t offset, uint64_t data) "Write: offset 0x%" PRIx64 " data 0x%" PRIx64
> diff --git a/include/hw/arm/allwinner-a10.h b/include/hw/arm/allwinner-a10.h
> index 2de7e402b2..c99ca6c1c4 100644
> --- a/include/hw/arm/allwinner-a10.h
> +++ b/include/hw/arm/allwinner-a10.h
> @@ -14,6 +14,7 @@
>   #include "hw/misc/allwinner-a10-dramc.h"
>   #include "hw/display/allwinner-a10-debe.h"
>   #include "hw/display/allwinner-a10-hdmi.h"
> +#include "hw/display/allwinner-a10-lcdc.h"
>   #include "hw/display/allwinner-gpu.h"
>   #include "hw/i2c/allwinner-i2c.h"
>   #include "hw/watchdog/allwinner-wdt.h"
> @@ -49,6 +50,7 @@ struct AwA10State {
>       AwA10DEBEState de_be0;
>       AwGpuState gpu;
>       AwA10HdmiState hdmi;
> +    AwA10LcdcState lcd0;
>       MemoryRegion sram_a;
>       EHCISysBusState ehci[AW_A10_NUM_USB];
>       OHCISysBusState ohci[AW_A10_NUM_USB];
> diff --git a/include/hw/display/allwinner-a10-lcdc.h b/include/hw/display/allwinner-a10-lcdc.h
> new file mode 100644
> index 0000000000..82f6d397fb
> --- /dev/null
> +++ b/include/hw/display/allwinner-a10-lcdc.h
> @@ -0,0 +1,77 @@
> +/*
> + * Allwinner A10 LCD Control Module emulation
> + *
> + * Copyright (C) 2023 Strahinja Jankovic <strahinja.p.jankovic@gmail.com>
> + *
> + * This program is free software: you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation, either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that 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/>.
> + */
> +
> +#ifndef HW_DISPLAY_ALLWINNER_A10_LCDC_H
> +#define HW_DISPLAY_ALLWINNER_A10_LCDC_H
> +
> +#include "qom/object.h"
> +#include "hw/ptimer.h"
> +#include "hw/sysbus.h"
> +#include "ui/console.h"
> +#include "hw/display/allwinner-a10-debe.h"
> +
> +/**
> + * @name Constants
> + * @{
> + */
> +
> +/** Size of register I/O address space used by LCDC device */
> +#define AW_A10_LCDC_IOSIZE        (0x1000)
> +
> +/** Total number of known registers */
> +#define AW_A10_LCDC_REGS_NUM      (AW_A10_LCDC_IOSIZE / sizeof(uint32_t))
> +
> +/** @} */
> +
> +/**
> + * @name Object model
> + * @{
> + */
> +
> +#define TYPE_AW_A10_LCDC    "allwinner-a10-lcdc"
> +OBJECT_DECLARE_SIMPLE_TYPE(AwA10LcdcState, AW_A10_LCDC)
> +
> +/** @} */
> +
> +/**
> + * Allwinner A10 LCDC object instance state.
> + */
> +struct AwA10LcdcState {
> +    /*< private >*/
> +    SysBusDevice parent_obj;
> +    /*< public >*/
> +    qemu_irq irq;
> +    struct ptimer_state *timer;
> +    QemuConsole *con;
> +
> +    MemoryRegionSection fbsection;
> +
> +    int invalidate;
> +    bool is_enabled;
> +
> +    AwA10DEBEState *debe;
> +
> +    /** Maps I/O registers in physical memory */
> +    MemoryRegion iomem;
> +
> +    /** Array of hardware registers */
> +    uint32_t regs[AW_A10_LCDC_REGS_NUM];
> +};
> +
> +#endif /* HW_DISPLAY_ALLWINNER_A10_LCDC_H */