lcdif_dma_cont.c

void lcdif_schedule_continuous_refresh(void *buffer, unsigned w, unsigned h)
{
    logf("refresh %dx%d\n", w, h);

    lcdif_write_reg(0x36, w - 1);
    lcdif_write_reg(0x37, 0);
    lcdif_write_reg(0x38, h - 1);
    lcdif_write_reg(0x39, 0);
    lcdif_write_reg(0x20, 0);
    lcdif_write_reg(0x21, 0);
    lcdif_write_data(false, 0x22);
    lcdif_wait_ready();
    __REG_CLR(HW_LCDIF_CTRL) = HW_LCDIF_CTRL__WORD_LENGTH_BM;
    __REG_CLR(HW_LCDIF_CTRL1) = HW_LCDIF_CTRL1__BYTE_PACKING_FORMAT_BM;
    __REG_SET(HW_LCDIF_CTRL) = HW_LCDIF_CTRL__WORD_LENGTH_16_BIT;
    __REG_SET(HW_LCDIF_CTRL1) = 0xf << HW_LCDIF_CTRL1__BYTE_PACKING_FORMAT_BP;
    g_lcdif_word_length = HW_LCDIF_CTRL__WORD_LENGTH_16_BIT;
    __REG_CLR(HW_LCDIF_CTRL) = HW_LCDIF_CTRL__INPUT_DATA_SWIZZLE_BM;
    __REG_SET(HW_LCDIF_CTRL) = HW_LCDIF_CTRL__INPUT_DATA_SWIZZLE__NO_SWAP;

    HW_LCDIF_TRANSFER_COUNT = (h << 16) | w;

    int rem_size = w * h * 2;
    for(int i = 0; i < NR_CMDS; i++)
    {
        int xfer_size = MIN(rem_size, IMX233_MAX_SINGLE_DMA_XFER_SIZE);
        lcdif_dma[i].cmd.next = &lcdif_dma[(i + 1) % NR_CMDS].cmd;
        lcdif_dma[i].cmd.buffer = buffer;
        lcdif_dma[i].cmd.cmd = HW_APB_CHx_CMD__COMMAND__READ |
            HW_APB_CHx_CMD__CHAIN |
            xfer_size << HW_APB_CHx_CMD__XFER_COUNT_BP;
        logf("rem_size=0x%x xfer_size=0x%x\n", rem_size, xfer_size);
        logf("cmd[%d][0x%x] nxt=0x%x buf=0x%x cmd=0x%x\n", i,
             (uint32_t)&lcdif_dma[i].cmd, lcdif_dma[i].cmd.next,
             lcdif_dma[i].cmd.buffer, lcdif_dma[i].cmd.cmd);
        rem_size -= xfer_size;
        buffer += xfer_size;
    }

    lcdif_dma[0].cmd.cmd |= 1 << HW_APB_CHx_CMD__CMDWORDS_BP;
    lcdif_dma[0].ctrl = HW_LCDIF_CTRL__RUN | HW_LCDIF_CTRL__DATA_SELECT;
    lcdif_dma[NR_CMDS - 1].cmd.cmd |= HW_APB_CHx_CMD__WAIT4ENDCMD;

    dma_clkgate_channel(APB_LCDIF, true);
    dma_reset_channel(APB_LCDIF);
    dma_start_command(APB_LCDIF, &lcdif_dma[0].cmd);
}