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

AKASHI Takahiro
2020-12-01T02:29:16Z

On Thu, Nov 26, 2020 at 10:18:26AM +0200, Adrian Hunter wrote:
> 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)

Okay

-Takahiro Akashi

> > + 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;
> > }
> >
>