/* Sets the SD bus clock speed */
void IP_SDMMC_SetClock(IP_SDMMC_001_T *pSDMMC, uint32_t clk_rate, uint32_t speed)
{
/* compute SD/MMC clock dividers */
uint32_t div;
div = ((clk_rate / speed) + 2) >> 1;
if ((div == pSDMMC->CLKDIV) && pSDMMC->CLKENA) {
return; /* Closest speed is already set */
}
/* disable clock */
pSDMMC->CLKENA = 0;
/* User divider 0 */
pSDMMC->CLKSRC = MCI_CLKSRC_CLKDIV0;
/* inform CIU */
IP_SDMMC_SendCmd(pSDMMC, MCI_CMD_UPD_CLK | MCI_CMD_PRV_DAT_WAIT, 0);
/* set divider 0 to desired value */
pSDMMC->CLKDIV = MCI_CLOCK_DIVIDER(0, div);
/* inform CIU */
IP_SDMMC_SendCmd(pSDMMC, MCI_CMD_UPD_CLK | MCI_CMD_PRV_DAT_WAIT, 0);
/* enable clock */
pSDMMC->CLKENA = MCI_CLKEN_ENABLE;
/* inform CIU */
IP_SDMMC_SendCmd(pSDMMC, MCI_CMD_UPD_CLK | MCI_CMD_PRV_DAT_WAIT, 0);
}
/*********************************************************************//**
* @brief Function to set speed of the clock going to card
* @param[in] speed Desired clock speed to the card
* @return None
**********************************************************************/
void sdif_set_clock(uint32_t speed)
{
/* compute SD/MMC clock dividers */
uint32_t div;
/* Exit if the clock is already set at the passed speed */
if (sdif_dev.sdif_slot_clk_rate == speed)
return;
div = ((sdif_dev.sdio_clk_rate / speed) + 2) >> 1;
sdif_dev.sdif_slot_clk_rate = speed;
if ((div == LPC_SDMMC->CLKDIV) && LPC_SDMMC->CLKENA)
return; /* Closest speed is already set */
/* disable clock */
LPC_SDMMC->CLKENA = 0;
/* User divider 0 */
LPC_SDMMC->CLKSRC = MCI_CLKSRC_CLKDIV0;
/* inform CIU */
sdif_send_cmd(MCI_CMD_UPD_CLK | MCI_CMD_PRV_DAT_WAIT, 0);
/* set divider 0 to desired value */
LPC_SDMMC->CLKDIV = MCI_CLOCK_DIVIDER(0, div);
/* inform CIU */
sdif_send_cmd(MCI_CMD_UPD_CLK | MCI_CMD_PRV_DAT_WAIT, 0);
/* enable clock */
LPC_SDMMC->CLKENA = MCI_CLKEN_ENABLE;
/* inform CIU */
sdif_send_cmd(MCI_CMD_UPD_CLK | MCI_CMD_PRV_DAT_WAIT, 0);
}
