st3m_gfx.c

#include "st3m_gfx.h"
// Submit a filled ctx descriptor to the rasterization pipeline.

#include <string.h>

#include "esp_log.h"
#include "esp_system.h"
#include "esp_task.h"
#include "esp_timer.h"
#include "freertos/FreeRTOS.h"
#include "freertos/queue.h"

// clang-format off
#include "ctx_config.h"
#include "ctx.h"
// clang-format on

#include "flow3r_bsp.h"
#include "st3m_counter.h"
#include "st3m_version.h"

// Each buffer  takes ~116kB SPIRAM. While one framebuffer is being blitted, the
// other one is being written to by the rasterizer.
#define ST3M_GFX_NBUFFERS 2
// More ctx drawlists than buffers so that micropython doesn't get starved when
// pipeline runs in lockstep.
#define ST3M_GFX_NCTX 3

// A framebuffer descriptor, pointing at a framebuffer.
typedef struct {
    // The numeric ID of this descriptor.
    int num;
    // SPIRAM buffer.
    uint16_t buffer[240 * 240];
    Ctx *ctx;
} st3m_framebuffer_desc_t;

// Get a free drawlist ctx to draw into.
//
// ticks_to_wait can be used to limit the time to wait for a free ctx
// descriptor, or portDELAY_MAX can be specified to wait forever. If the timeout
// expires, NULL will be returned.
static st3m_ctx_desc_t *st3m_gfx_drawctx_free_get(TickType_t ticks_to_wait);

// Submit a filled ctx descriptor to the rasterization pipeline.
static void st3m_gfx_drawctx_pipe_put(st3m_ctx_desc_t *desc);

static const char *TAG = "st3m-gfx";

// Framebuffer descriptors, containing framebuffer and ctx for each of the
// framebuffers.
//
// These live in SPIRAM, as we don't have enough space in SRAM/IRAM.
EXT_RAM_BSS_ATTR static st3m_framebuffer_desc_t
    framebuffer_descs[ST3M_GFX_NBUFFERS];

#define OVERLAY_WIDTH 120
#define OVERLAY_HEIGHT 160
#define OVERLAY_X 60
#define OVERLAY_Y 0

static int _st3m_overlay_height = 0;
EXT_RAM_BSS_ATTR static uint8_t
    st3m_overlay_fb[OVERLAY_WIDTH * OVERLAY_HEIGHT * 4];
EXT_RAM_BSS_ATTR uint16_t st3m_overlay_backup[OVERLAY_WIDTH * OVERLAY_HEIGHT];
static Ctx *_st3m_overlay_ctx = NULL;

static st3m_ctx_desc_t dctx_descs[ST3M_GFX_NCTX];

// Queue of free framebuffer descriptors, written into by crtc once rendered,