On Mon, Apr 15, 2024 at 09:58:31AM +0300, Adrian Hunter wrote:
> On 14/04/24 19:41, Jisheng Zhang wrote:
> > Implement the .platform_execute_tuning for Sophgo CV1800B and SG200X.
> > Some code is borrowed from sdhci-esdhc-imx.c. The tuning result is
> > similar as the one of SoC vendor's SDK.
> >
> > Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx>
>
> One comment, otherwise:
>
> Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
>
> > ---
> > drivers/mmc/host/sdhci-of-dwcmshc.c | 112 ++++++++++++++++++++++++++++
> > 1 file changed, 112 insertions(+)
> >
> > diff --git a/drivers/mmc/host/sdhci-of-dwcmshc.c b/drivers/mmc/host/sdhci-of-dwcmshc.c
> > index ab4b964d4058..7b55acd9830c 100644
> > --- a/drivers/mmc/host/sdhci-of-dwcmshc.c
> > +++ b/drivers/mmc/host/sdhci-of-dwcmshc.c
> > @@ -66,6 +66,10 @@
> > #define CV18XX_SDHCI_PHY_CONFIG 0x4c
> > #define CV18XX_PHY_TX_BPS BIT(0)
> >
> > +#define CV18XX_TUNE_MAX 128
> > +#define CV18XX_TUNE_STEP 1
> > +#define CV18XX_RETRY_TUNING_MAX 50
> > +
> > /* Rockchip specific Registers */
> > #define DWCMSHC_EMMC_DLL_CTRL 0x800
> > #define DWCMSHC_EMMC_DLL_RXCLK 0x804
> > @@ -685,6 +689,113 @@ static void cv18xx_sdhci_reset(struct sdhci_host *host, u8 mask)
> > sdhci_writel(host, val, priv->vendor_specific_area1 + CV18XX_SDHCI_PHY_TX_RX_DLY);
> > }
> >
> > +static void cv18xx_sdhci_set_tap(struct sdhci_host *host, int tap)
> > +{
> > + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> > + struct dwcmshc_priv *priv = sdhci_pltfm_priv(pltfm_host);
> > + u16 clk;
> > + u32 val;
> > +
> > + clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
> > + clk &= ~SDHCI_CLOCK_CARD_EN;
> > + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> > +
> > + val = sdhci_readl(host, priv->vendor_specific_area1 + CV18XX_SDHCI_MSHC_CTRL);
> > + val &= ~CV18XX_LATANCY_1T;
> > + sdhci_writel(host, val, priv->vendor_specific_area1 + CV18XX_SDHCI_MSHC_CTRL);
> > +
> > + val = (FIELD_PREP(CV18XX_PHY_TX_DLY_MSK, 0) |
> > + FIELD_PREP(CV18XX_PHY_TX_SRC_MSK, CV18XX_PHY_TX_SRC_INVERT_CLK_TX) |
> > + FIELD_PREP(CV18XX_PHY_RX_DLY_MSK, tap));
> > + sdhci_writel(host, val, priv->vendor_specific_area1 + CV18XX_SDHCI_PHY_TX_RX_DLY);
> > +
> > + sdhci_writel(host, 0, priv->vendor_specific_area1 + CV18XX_SDHCI_PHY_CONFIG);
> > +
> > + clk |= SDHCI_CLOCK_CARD_EN;
> > + sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
> > + mdelay(1);
>
> Did you consider usleep_range() instead of mdelay()?
Good idea, will test and send out a v2.
>
> > +}
> > +
> > +static int cv18xx_retry_tuning(struct mmc_host *mmc, u32 opcode, int *cmd_error)
> > +{
> > + int ret, retry = 0;
> > +
> > + while (retry < CV18XX_RETRY_TUNING_MAX) {
> > + ret = mmc_send_tuning(mmc, opcode, NULL);
> > + if (ret)
> > + return ret;
> > + retry++;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static void cv18xx_sdhci_post_tuning(struct sdhci_host *host)
> > +{
> > + u32 val;
> > +
> > + val = sdhci_readl(host, SDHCI_INT_STATUS);
> > + val |= SDHCI_INT_DATA_AVAIL;
> > + sdhci_writel(host, val, SDHCI_INT_STATUS);
> > +
> > + sdhci_reset(host, SDHCI_RESET_CMD | SDHCI_RESET_DATA);
> > +}
> > +
> > +static int cv18xx_sdhci_execute_tuning(struct sdhci_host *host, u32 opcode)
> > +{
> > + int min, max, avg, ret;
> > + int win_length, target_min, target_max, target_win_length;
> > +
> > + min = max = 0;
> > + target_win_length = 0;
> > +
> > + sdhci_reset_tuning(host);
> > +
> > + while (max < CV18XX_TUNE_MAX) {
> > + /* find the mininum delay first which can pass tuning */
> > + while (min < CV18XX_TUNE_MAX) {
> > + cv18xx_sdhci_set_tap(host, min);
> > + if (!cv18xx_retry_tuning(host->mmc, opcode, NULL))
> > + break;
> > + min += CV18XX_TUNE_STEP;
> > + }
> > +
> > + /* find the maxinum delay which can not pass tuning */
> > + max = min + CV18XX_TUNE_STEP;
> > + while (max < CV18XX_TUNE_MAX) {
> > + cv18xx_sdhci_set_tap(host, max);
> > + if (cv18xx_retry_tuning(host->mmc, opcode, NULL)) {
> > + max -= CV18XX_TUNE_STEP;
> > + break;
> > + }
> > + max += CV18XX_TUNE_STEP;
> > + }
> > +
> > + win_length = max - min + 1;
> > + /* get the largest pass window */
> > + if (win_length > target_win_length) {
> > + target_win_length = win_length;
> > + target_min = min;
> > + target_max = max;
> > + }
> > +
> > + /* continue to find the next pass window */
> > + min = max + CV18XX_TUNE_STEP;
> > + }
> > +
> > + cv18xx_sdhci_post_tuning(host);
> > +
> > + /* use average delay to get the best timing */
> > + avg = (target_min + target_max) / 2;
> > + cv18xx_sdhci_set_tap(host, avg);
> > + ret = mmc_send_tuning(host->mmc, opcode, NULL);
> > +
> > + dev_dbg(mmc_dev(host->mmc), "tuning %s at 0x%x ret %d\n",
> > + ret ? "failed" : "passed", avg, ret);
> > +
> > + return ret;
> > +}
> > +
> > static const struct sdhci_ops sdhci_dwcmshc_ops = {
> > .set_clock = sdhci_set_clock,
> > .set_bus_width = sdhci_set_bus_width,
> > @@ -721,6 +832,7 @@ static const struct sdhci_ops sdhci_dwcmshc_cv18xx_ops = {
> > .get_max_clock = dwcmshc_get_max_clock,
> > .reset = cv18xx_sdhci_reset,
> > .adma_write_desc = dwcmshc_adma_write_desc,
> > + .platform_execute_tuning = cv18xx_sdhci_execute_tuning,
> > };
> >
> > static const struct sdhci_pltfm_data sdhci_dwcmshc_pdata = {
>
