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

AKASHI Takahiro
2020-11-06T02:29:00Z

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)) {
+ 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;
}
--
2.28.0