the tune result of hs200 mode at 200Mhz is not suitable for 50Mhz,
mmc_select_hs400() will set clock frequency to 50Mhz, use defalut
tune setting for 50Mhz to avoid CRC error.
Signed-off-by: Chaotian Jing <chaotian.jing@xxxxxxxxxxxx>
---
drivers/mmc/host/mtk-sd.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)
diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
index 4d7ce65..4b175a6 100644
--- a/drivers/mmc/host/mtk-sd.c
+++ b/drivers/mmc/host/mtk-sd.c
@@ -287,6 +287,11 @@ struct msdc_save_para {
u32 emmc50_cfg0;
};
+struct msdc_tune_para {
+ u32 iocon;
+ u32 pad_tune;
+};
+
struct msdc_delay_phase {
u8 maxlen;
u8 start;
@@ -328,6 +333,8 @@ struct msdc_host {
u32 hs400_ds_delay;
bool hs400_mode; /* current eMMC will run at hs400 mode */
struct msdc_save_para save_para; /* used when gate HCLK */
+ struct msdc_tune_para def_tune_para; /* default tune setting */
+ struct msdc_tune_para saved_tune_para; /* tune result of CMD21/CMD19 */
};
static void sdr_set_bits(void __iomem *reg, u32 bs)
@@ -583,6 +590,18 @@ static void msdc_set_mclk(struct msdc_host *host, unsigned char timing, u32 hz)
msdc_set_timeout(host, host->timeout_ns, host->timeout_clks);
sdr_set_bits(host->base + MSDC_INTEN, flags);
+ /*
+ * mmc_select_hs400() will drop to 50Mhz and High speed mode,
+ * tune result of hs200/200Mhz is not suitable for 50Mhz
+ */
+ if (host->sclk <= 52000000) {
+ writel(host->def_tune_para.iocon, host->base + MSDC_IOCON);
+ writel(host->def_tune_para.pad_tune, host->base + MSDC_PAD_TUNE);
+ } else {
+ writel(host->saved_tune_para.iocon, host->base + MSDC_IOCON);
+ writel(host->saved_tune_para.pad_tune, host->base + MSDC_PAD_TUNE);
+ }
+
dev_dbg(host->dev, "sclk: %d, timing: %d\n", host->sclk, timing);
}
@@ -1159,6 +1178,8 @@ static void msdc_init_hw(struct msdc_host *host)
/* Configure to default data timeout */
sdr_set_field(host->base + SDC_CFG, SDC_CFG_DTOC, 3);
+ host->def_tune_para.iocon = readl(host->base + MSDC_IOCON);
+ host->def_tune_para.pad_tune = readl(host->base + MSDC_PAD_TUNE);
dev_dbg(host->dev, "init hardware done!");
}
@@ -1409,6 +1430,8 @@ static int msdc_execute_tuning(struct mmc_host *mmc, u32 opcode)
dev_err(host->dev, "Tune data fail!\n");
}
+ host->saved_tune_para.iocon = readl(host->base + MSDC_IOCON);
+ host->saved_tune_para.pad_tune = readl(host->base + MSDC_PAD_TUNE);
return ret;
}
--
1.8.1.1.dirty
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
