Re: [RFC PATCH v3.1 19/27] mmc: sdhci-uhs2: add set_reg() to initialise the interface

Adrian Hunter
2020-11-26T08:18:55Z

On 6/11/20 4:27 am, AKASHI Takahiro wrote:
> This is a sdhci version of mmc's uhs2_set_reg operation.
> UHS-II interface (related registers) will be initialised here.
>
> Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> ---
> drivers/mmc/host/sdhci-uhs2.c | 103 ++++++++++++++++++++++++++++++++++
> 1 file changed, 103 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
> index 55362ace1857..d8afb99a9918 100644
> --- a/drivers/mmc/host/sdhci-uhs2.c
> +++ b/drivers/mmc/host/sdhci-uhs2.c
> @@ -332,6 +332,68 @@ static void __sdhci_uhs2_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> spin_unlock_irqrestore(&host->lock, flags);
> }
>
> +/* TODO: move this function to sdhci.c */
> +static void sdhci_clear_set_irqs(struct sdhci_host *host, u32 clear, u32 set)
> +{
> + u32 ier;
> +
> + ier = sdhci_readl(host, SDHCI_INT_ENABLE);
> + ier &= ~clear;
> + ier |= set;
> + sdhci_writel(host, ier, SDHCI_INT_ENABLE);
> + sdhci_writel(host, ier, SDHCI_SIGNAL_ENABLE);
> +}
> +
> +static void sdhci_uhs2_set_config(struct sdhci_host *host)
> +{
> + u32 value;
> + u16 sdhci_uhs2_set_ptr = sdhci_readw(host, SDHCI_UHS2_SET_PTR);
> + u16 sdhci_uhs2_gen_set_reg = (sdhci_uhs2_set_ptr + 0);
> + 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 */
> + sdhci_writel(host, host->mmc->uhs2_caps.n_lanes_set <<
> + SDHCI_UHS2_GEN_SET_N_LANES_POS, sdhci_uhs2_gen_set_reg);
> +
> + /* Set PHY Settings */
> + value = (host->mmc->uhs2_caps.n_lss_dir_set <<
> + SDHCI_UHS2_PHY_SET_N_LSS_DIR_POS) |
> + (host->mmc->uhs2_caps.n_lss_sync_set <<
> + SDHCI_UHS2_PHY_SET_N_LSS_SYN_POS);
> + if (host->mmc->flags & MMC_UHS2_SPEED_B)
> + value |= 1 << SDHCI_UHS2_PHY_SET_SPEED_POS;
> + sdhci_writel(host, value, sdhci_uhs2_phy_set_reg);
> +
> + /* Set LINK-TRAN Settings */
> + value = (host->mmc->uhs2_caps.max_retry_set <<
> + SDHCI_UHS2_TRAN_SET_RETRY_CNT_POS) |
> + (host->mmc->uhs2_caps.n_fcu_set <<
> + SDHCI_UHS2_TRAN_SET_N_FCU_POS);
> + 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 = 100;
> +
> + while (!(sdhci_readl(host, SDHCI_PRESENT_STATE) &
> + SDHCI_UHS2_IN_DORMANT_STATE)) {

Can use read_poll_timeout(sdhci_readl,..., host, SDHCI_PRESENT_STATE)

> + if (timeout == 0) {
> + pr_warn("%s: UHS2 IN_DORMANT fail in 100ms.\n",
> + mmc_hostname(host->mmc));
> + sdhci_dumpregs(host);
> + return -EIO;
> + }
> + timeout--;
> + mdelay(1);
> + }
> + return 0;
> +}
> +
> /*****************************************************************************\
> * *
> * MMC callbacks *
> @@ -422,6 +484,45 @@ static void sdhci_uhs2_enable_clk(struct mmc_host *mmc)
> }
> }
>
> +static int sdhci_uhs2_set_reg(struct mmc_host *mmc, enum uhs2_act act)
> +{
> + struct sdhci_host *host = mmc_priv(mmc);
> + unsigned long flags;
> + int err = 0;
> + u16 sdhci_uhs2_set_ptr = sdhci_readw(host, SDHCI_UHS2_SET_PTR);
> + u16 sdhci_uhs2_phy_set_reg = (sdhci_uhs2_set_ptr + 4);
> +
> + DBG("Begin sdhci_uhs2_set_reg, act %d.\n", act);
> + spin_lock_irqsave(&host->lock, flags);
> +
> + switch (act) {
> + case SET_CONFIG:
> + sdhci_uhs2_set_config(host);
> + break;
> + case ENABLE_INT:
> + sdhci_clear_set_irqs(host, 0, SDHCI_INT_CARD_INT);
> + break;
> + case DISABLE_INT:
> + sdhci_clear_set_irqs(host, SDHCI_INT_CARD_INT, 0);
> + break;
> + case SET_SPEED_B:
> + sdhci_writeb(host, 1 << SDHCI_UHS2_PHY_SET_SPEED_POS,
> + sdhci_uhs2_phy_set_reg);
> + break;
> + case CHECK_DORMANT:
> + err = sdhci_uhs2_check_dormant(host);
> + break;
> + default:
> + pr_err("%s: input action %d is wrong!\n",
> + mmc_hostname(host->mmc), act);
> + err = -EIO;
> + break;
> + }
> +
> + spin_unlock_irqrestore(&host->lock, flags);
> + return err;
> +}
> +
> /*****************************************************************************\
> * *
> * Driver init/exit *
> @@ -597,6 +698,8 @@ static int sdhci_uhs2_host_ops_init(struct sdhci_host *host)
> host->mmc_host_ops.uhs2_disable_clk = sdhci_uhs2_disable_clk;
> if (!host->mmc_host_ops.uhs2_enable_clk)
> host->mmc_host_ops.uhs2_enable_clk = sdhci_uhs2_enable_clk;
> + if (!host->mmc_host_ops.uhs2_set_reg)
> + host->mmc_host_ops.uhs2_set_reg = sdhci_uhs2_set_reg;
>
> return 0;
> }
>