diff options
| author | Ye Li <ye.li@nxp.com> | 2019-01-07 03:18:06 +0000 |
|---|---|---|
| committer | Peng Fan <peng.fan@nxp.com> | 2019-05-03 20:03:41 +0800 |
| commit | 72a89e0da5ac6a4ab929b15a2b656f04f50767f6 (patch) | |
| tree | 311a4c938f6fb4afd4623f8f4179aa75757471f0 /drivers | |
| parent | b4ee6daad7a2604ca9466b2ba48de86cc27d381f (diff) | |
mmc: fsl_esdhc: fix sd/mmc ddr mode clock setting issue
When sd/mmc work at DDR mode, like HS400/HS400ES/DDR52/DDR50 mode,
the output clock rate is half of the internal clock rate.
This patch set the DDR_EN bit first for DDR mode, hardware divide
the usdhc clock automatically, then follow the original sdr clock
setting method.
Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Signed-off-by: Ye Li <ye.li@nxp.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/mmc/fsl_esdhc.c | 23 |
1 files changed, 18 insertions, 5 deletions
diff --git a/drivers/mmc/fsl_esdhc.c b/drivers/mmc/fsl_esdhc.c index 9e34557d16..60972014c4 100644 --- a/drivers/mmc/fsl_esdhc.c +++ b/drivers/mmc/fsl_esdhc.c @@ -614,18 +614,31 @@ static void set_sysctl(struct fsl_esdhc_priv *priv, struct mmc *mmc, uint clock) #else int pre_div = 2; #endif - int ddr_pre_div = mmc->ddr_mode ? 2 : 1; int sdhc_clk = priv->sdhc_clk; uint clk; + /* + * For ddr mode, usdhc need to enable DDR mode first, after select + * this DDR mode, usdhc will automatically divide the usdhc clock + */ + if (mmc->ddr_mode) { + writel(readl(®s->mixctrl) | MIX_CTRL_DDREN, ®s->mixctrl); + sdhc_clk >>= 1; + } + if (clock < mmc->cfg->f_min) clock = mmc->cfg->f_min; - while (sdhc_clk / (16 * pre_div * ddr_pre_div) > clock && pre_div < 256) - pre_div *= 2; + if (sdhc_clk / 16 > clock) { + for (; pre_div < 256; pre_div *= 2) + if ((sdhc_clk / pre_div) <= (clock * 16)) + break; + } else + pre_div = 1; - while (sdhc_clk / (div * pre_div * ddr_pre_div) > clock && div < 16) - div++; + for (div = 1; div <= 16; div++) + if ((sdhc_clk / (div * pre_div)) <= clock) + break; pre_div >>= 1; div -= 1; |