Re: [PATCH V12 17/23] mmc: sdhci-uhs2: add uhs2_control() to initialise the interface

[Ulf Hansson]

On Fri, 15 Sept 2023 at 11:44, Victor Shih <victorshihgli@xxxxxxxxx> wrote:
>
> From: Victor Shih <victor.shih@xxxxxxxxxxxxxxxxxxx>
>
> This is a sdhci version of mmc's uhs2_set_reg operation.
> UHS-II interface (related registers) will be initialised here.

Please clarify this. It's not entirely easy to understand what goes on
by reading the commit message above.

Again, the similar comments as I provided for patch15 applies to
$subject patch too.

>
> Signed-off-by: Ben Chuang <ben.chuang@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@xxxxxxxxxx>
> Signed-off-by: Victor Shih <victor.shih@xxxxxxxxxxxxxxxxxxx>
> Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> ---
>
> Updates in V8:
>  - Reorder the definitions and lose the parentheses in
>    sdhci_uhs2_set_config().
>  - read_poll_timeout() to instead of read_poll_timeout_atomic()
>    in sdhci_uhs2_check_dormant().
>
> Updates in V7:
>  - Remove unnecessary function.
>
> Updates in V6:
>  - Remove unnecessary function.
>  - Remove unnecessary parameter when call the DBG().
>  - Cancel export state of some functions.
>
> ---
>
>  drivers/mmc/host/sdhci-uhs2.c | 88 +++++++++++++++++++++++++++++++++++
>  1 file changed, 88 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
> index af1b0c5e48fd..09b86fec9f7b 100644
> --- a/drivers/mmc/host/sdhci-uhs2.c
> +++ b/drivers/mmc/host/sdhci-uhs2.c
> @@ -278,6 +278,48 @@ static void __sdhci_uhs2_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
>         sdhci_set_clock(host, host->clock);
>  }
>
> +static void sdhci_uhs2_set_config(struct sdhci_host *host)
> +{
> +       u32 value;
> +       u16 sdhci_uhs2_set_ptr = sdhci_readw(host, SDHCI_UHS2_SETTINGS_PTR);
> +       u16 sdhci_uhs2_gen_set_reg      = sdhci_uhs2_set_ptr;
> +       u16 sdhci_uhs2_phy_set_reg      = sdhci_uhs2_set_ptr + 4;
> +       u16 sdhci_uhs2_tran_set_reg     = sdhci_uhs2_set_ptr + 8;
> +       u16 sdhci_uhs2_tran_set_1_reg   = sdhci_uhs2_set_ptr + 12;
> +
> +       /* Set Gen Settings */
> +       value = FIELD_PREP(SDHCI_UHS2_GEN_SETTINGS_N_LANES_MASK, host->mmc->uhs2_caps.n_lanes_set);
> +       sdhci_writel(host, value, sdhci_uhs2_gen_set_reg);
> +
> +       /* Set PHY Settings */
> +       value = FIELD_PREP(SDHCI_UHS2_PHY_N_LSS_DIR_MASK, host->mmc->uhs2_caps.n_lss_dir_set) |
> +               FIELD_PREP(SDHCI_UHS2_PHY_N_LSS_SYN_MASK, host->mmc->uhs2_caps.n_lss_sync_set);
> +       if (host->mmc->ios.timing == MMC_TIMING_UHS2_SPEED_B ||
> +           host->mmc->ios.timing == MMC_TIMING_UHS2_SPEED_B_HD)
> +               value |= SDHCI_UHS2_PHY_SET_SPEED_B;
> +       sdhci_writel(host, value, sdhci_uhs2_phy_set_reg);
> +
> +       /* Set LINK-TRAN Settings */
> +       value = FIELD_PREP(SDHCI_UHS2_TRAN_RETRY_CNT_MASK, host->mmc->uhs2_caps.max_retry_set) |
> +               FIELD_PREP(SDHCI_UHS2_TRAN_N_FCU_MASK, host->mmc->uhs2_caps.n_fcu_set);
> +       sdhci_writel(host, value, sdhci_uhs2_tran_set_reg);
> +       sdhci_writel(host, host->mmc->uhs2_caps.n_data_gap_set, sdhci_uhs2_tran_set_1_reg);
> +}
> +
> +static int sdhci_uhs2_check_dormant(struct sdhci_host *host)
> +{
> +       int timeout = 100000; /* 100ms */

Define.

> +       u32 val;
> +
> +       if (read_poll_timeout(sdhci_readl, val, (val & SDHCI_UHS2_IN_DORMANT_STATE),
> +                             100, timeout, true, host, SDHCI_PRESENT_STATE)) {
> +               pr_warn("%s: UHS2 IN_DORMANT fail in 100ms.\n", mmc_hostname(host->mmc));
> +               sdhci_dumpregs(host);
> +               return -EIO;
> +       }
> +       return 0;
> +}
> +
>  /*****************************************************************************\
>   *                                                                           *
>   * MMC callbacks                                                             *
> @@ -359,6 +401,51 @@ static int sdhci_uhs2_enable_clk(struct mmc_host *mmc)
>         return 0;
>  }
>
> +static int sdhci_uhs2_do_detect_init(struct mmc_host *mmc);

Please re-order the code so this declaration isn't needed. And make it
part of the patch that introduced the function, not in the $subject
patch.

> +
> +static int sdhci_uhs2_control(struct mmc_host *mmc, enum sd_uhs2_operation op)
> +{
> +       struct sdhci_host *host = mmc_priv(mmc);
> +       struct mmc_ios *ios = &mmc->ios;
> +       int err = 0;
> +
> +       DBG("Begin uhs2 control, act %d.\n", op);
> +
> +       switch (op) {
> +       case UHS2_PHY_INIT:
> +               err = sdhci_uhs2_do_detect_init(mmc);
> +               break;
> +       case UHS2_SET_CONFIG:
> +               sdhci_uhs2_set_config(host);
> +               break;
> +       case UHS2_ENABLE_INT:
> +               sdhci_uhs2_clear_set_irqs(host, 0, SDHCI_INT_CARD_INT);
> +               break;
> +       case UHS2_DISABLE_INT:
> +               sdhci_uhs2_clear_set_irqs(host, SDHCI_INT_CARD_INT, 0);
> +               break;
> +       case UHS2_CHECK_DORMANT:
> +               err = sdhci_uhs2_check_dormant(host);
> +               break;
> +       case UHS2_DISABLE_CLK:
> +               err = sdhci_uhs2_disable_clk(mmc);
> +               break;
> +       case UHS2_ENABLE_CLK:
> +               err = sdhci_uhs2_enable_clk(mmc);
> +               break;
> +       case UHS2_SET_IOS:
> +               err = sdhci_uhs2_set_ios(mmc, ios);
> +               break;
> +       default:
> +               pr_err("%s: input sd uhs2 operation %d is wrong!\n",
> +                      mmc_hostname(host->mmc), op);
> +               err = -EIO;
> +               break;
> +       }
> +
> +       return err;
> +}
> +
>  /*****************************************************************************\
>   *                                                                           *
>   * Driver init/exit                                                          *
> @@ -481,6 +568,7 @@ static int sdhci_uhs2_host_ops_init(struct sdhci_host *host)
>  {
>         host->mmc_host_ops.start_signal_voltage_switch =
>                 sdhci_uhs2_start_signal_voltage_switch;
> +       host->mmc_host_ops.uhs2_control = sdhci_uhs2_control;
>
>         return 0;
>  }

Kind regards
Uffe