Mirrors/u-boot
2
0
Fork 0
mirror of https://github.com/AsahiLinux/u-boot synced 2024-11-11 23:47:24 +00:00
Code Issues Projects Releases Packages Wiki Activity

mmc: fsl_esdhc_imx: optimize the timing setting

Browse source 
For imx usdhc/esdhc, once set the DDR_EN, enable the DDR mode, the
card clock will be divied by 2 automatically by the host. So need
to first config the DDR_EN correctly, then update the card clock.
This will make sure the actual card clock is as our expected.
IC also suggest config the DDR_EN firstly, then config the clock
divider.

For HS400/HS400ES mode, need to config the strobe dll, this need
to based on the correct target clock rate, so need to do this after
clock rate is update.

Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
This commit is contained in:
Haibo Chen 2020-11-03 17:18:35 +08:00 committed by Stefano Babic
parent ea51af2fdd
commit 5d772196d9
1 changed files with 24 additions and 8 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

32
drivers/mmc/fsl_esdhc_imx.c
View file

@ -760,7 +760,6 @@ static int esdhc_set_timing(struct mmc *mmc)
case MMC_HS_400_ES:
mixctrl |= MIX_CTRL_DDREN | MIX_CTRL_HS400_EN;
esdhc_write32(&regs->mixctrl, mixctrl);
esdhc_set_strobe_dll(mmc);
break;
case MMC_HS:
case MMC_HS_52:
@ -933,6 +932,23 @@ static int esdhc_set_ios_common(struct fsl_esdhc_priv *priv, struct mmc *mmc)
int ret __maybe_unused;
u32 clock;
#ifdef MMC_SUPPORTS_TUNING
/*
* call esdhc_set_timing() before update the clock rate,
* This is because current we support DDR and SDR mode,
* Once the DDR_EN bit is set, the card clock will be
* divide by 2 automatically. So need to do this before
* setting clock rate.
*/
if (priv->mode != mmc->selected_mode) {
ret = esdhc_set_timing(mmc);
if (ret) {
printf("esdhc_set_timing error %d\n", ret);
return ret;
}
}
#endif
/* Set the clock speed */
clock = mmc->clock;
if (clock < mmc->cfg->f_min)
@ -957,13 +973,13 @@ static int esdhc_set_ios_common(struct fsl_esdhc_priv *priv, struct mmc *mmc)
#endif
}
if (priv->mode != mmc->selected_mode) {
ret = esdhc_set_timing(mmc);
if (ret) {
printf("esdhc_set_timing error %d\n", ret);
return ret;
}
}
/*
* For HS400/HS400ES mode, make sure set the strobe dll in the
* target clock rate. So call esdhc_set_strobe_dll() after the
* clock updated.
*/
if (mmc->selected_mode == MMC_HS_400 || mmc->selected_mode == MMC_HS_400_ES)
esdhc_set_strobe_dll(mmc);
if (priv->signal_voltage != mmc->signal_voltage) {
ret = esdhc_set_voltage(mmc);