max80_fw/rv32/esp.c

#include "compiler.h"
#include "common.h"
#include "io.h"
#include "console.h"
#include "esplink.h"

struct esplink_head __esplink_head esplink_head;

uint32_t __esplink esplink[(65536 - sizeof(struct esplink_head)) >> 2];

IRQHANDLER(esp,0)
{
    uint32_t irqstatus = ESP_CPU_IRQ;
    ESP_CPU_IRQ_CLR = irqstatus;

    if (irqstatus & (1 << EL_DIRQ_UNDERRUN)) {
	con_printf("[ESP] ESP link memory underrun!!\n");
	ESP_SPI_IRQ = (0x10 << EL_UIRQ_READY); /* Block writes, reinitialize! */
    }
    if (irqstatus & (1 << EL_DIRQ_HELLO)) {
	con_printf("[ESP] Got hello, sending ready...\n");
	/* Hello, are you there? Yes, I'm here, and you can write data now */
	ESP_SPI_IRQ_SET = (0x10 << EL_UIRQ_READY)|(0x10 << EL_UIRQ_WREN);
    }
}

void esp_init(void)
{
    static char __dram_data esp_signature[] = "Hej tomtebuggar slå i glasen!";

    ESP_CPU_IRQ                = 0;
    ESP_SPI_IRQ                = 0;

    memset(&esplink_head, 0, sizeof esplink_head);
    
    esplink_head.hlen          = sizeof esplink_head;
    esplink_head.board.cfg     = SYS_BOARDCFG;
    esplink_head.signature     = esp_signature;
    esplink_head.signature_len = sizeof esp_signature - 1;

    esplink_head.magic         = ESPLINK_HEAD_MAGIC;
    ESP_SPI_IRQ                = (0x10 << EL_UIRQ_READY);

    unmask_irq(ESP_IRQ);
}