[RFC PATCH v3.1 17/27] mmc: sdhci-uhs2: add detect_init() to detect the interface

AKASHI Takahiro
2020-11-06T02:28:54Z

Sdhci_uhs2_do_detect_init() is a sdhci version of mmc's uhs2_detect_init
operation. After detected, the host's UHS-II capabilities will be set up
here and interrupts will also be enabled.

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 | 160 ++++++++++++++++++++++++++++++++++
1 file changed, 160 insertions(+)

diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
index 637464748cc4..994dff967e85 100644
--- a/drivers/mmc/host/sdhci-uhs2.c
+++ b/drivers/mmc/host/sdhci-uhs2.c
@@ -391,12 +391,172 @@ void sdhci_uhs2_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
* *
\*****************************************************************************/

+static int sdhci_uhs2_interface_detect(struct sdhci_host *host)
+{
+ int timeout = 100;
+
+ udelay(200); /* wait for 200us before check */
+
+ while (!(sdhci_readl(host, SDHCI_PRESENT_STATE) &
+ SDHCI_UHS2_IF_DETECT)) {
+ if (timeout == 0) {
+ pr_warn("%s: not detect UHS2 interface in 200us.\n",
+ mmc_hostname(host->mmc));
+ sdhci_dumpregs(host);
+ return -EIO;
+ }
+ timeout--;
+ mdelay(1);
+ }
+
+ /* Enable UHS2 error interrupts */
+ sdhci_uhs2_clear_set_irqs(host, SDHCI_INT_ALL_MASK,
+ SDHCI_UHS2_ERR_INT_STATUS_MASK);
+
+ timeout = 150;
+ while (!(sdhci_readl(host, SDHCI_PRESENT_STATE) &
+ SDHCI_UHS2_LANE_SYNC)) {
+ if (timeout == 0) {
+ pr_warn("%s: UHS2 Lane sync fail in 150ms.\n",
+ mmc_hostname(host->mmc));
+ sdhci_dumpregs(host);
+ return -EIO;
+ }
+ timeout--;
+ mdelay(1);
+ }
+
+ DBG("%s: UHS2 Lane synchronized in UHS2 mode, PHY is initialized.\n",
+ mmc_hostname(host->mmc));
+ return 0;
+}
+
+static int sdhci_uhs2_init(struct sdhci_host *host)
+{
+ u16 caps_ptr = 0;
+ u32 caps_gen = 0;
+ u32 caps_phy = 0;
+ u32 caps_tran[2] = {0, 0};
+ struct mmc_host *mmc = host->mmc;
+
+ /*
+ * TODO: may add corresponding members in sdhci_host to
+ * keep these caps.
+ */
+ caps_ptr = sdhci_readw(host, SDHCI_UHS2_HOST_CAPS_PTR);
+ if (caps_ptr < 0x100 || caps_ptr > 0x1FF) {
+ pr_err("%s: SDHCI_UHS2_HOST_CAPS_PTR(%d) is wrong.\n",
+ mmc_hostname(mmc), caps_ptr);
+ return -ENODEV;
+ }
+ caps_gen = sdhci_readl(host,
+ caps_ptr + SDHCI_UHS2_HOST_CAPS_GEN_OFFSET);
+ caps_phy = sdhci_readl(host,
+ caps_ptr + SDHCI_UHS2_HOST_CAPS_PHY_OFFSET);
+ caps_tran[0] = sdhci_readl(host,
+ caps_ptr + SDHCI_UHS2_HOST_CAPS_TRAN_OFFSET);
+ caps_tran[1] = sdhci_readl(host,
+ caps_ptr
+ + SDHCI_UHS2_HOST_CAPS_TRAN_1_OFFSET);
+
+ /* General Caps */
+ mmc->uhs2_caps.dap = caps_gen & SDHCI_UHS2_HOST_CAPS_GEN_DAP_MASK;
+ mmc->uhs2_caps.gap = (caps_gen & SDHCI_UHS2_HOST_CAPS_GEN_GAP_MASK) >>
+ SDHCI_UHS2_HOST_CAPS_GEN_GAP_SHIFT;
+ mmc->uhs2_caps.n_lanes = (caps_gen & SDHCI_UHS2_HOST_CAPS_GEN_LANE_MASK)
+ >> SDHCI_UHS2_HOST_CAPS_GEN_LANE_SHIFT;
+ mmc->uhs2_caps.addr64 =
+ (caps_gen & SDHCI_UHS2_HOST_CAPS_GEN_ADDR_64) ? 1 : 0;
+ mmc->uhs2_caps.card_type =
+ (caps_gen & SDHCI_UHS2_HOST_CAPS_GEN_DEV_TYPE_MASK) >>
+ SDHCI_UHS2_HOST_CAPS_GEN_DEV_TYPE_SHIFT;
+
+ /* PHY Caps */
+ mmc->uhs2_caps.phy_rev = caps_phy & SDHCI_UHS2_HOST_CAPS_PHY_REV_MASK;
+ mmc->uhs2_caps.speed_range =
+ (caps_phy & SDHCI_UHS2_HOST_CAPS_PHY_RANGE_MASK)
+ >> SDHCI_UHS2_HOST_CAPS_PHY_RANGE_SHIFT;
+ mmc->uhs2_caps.n_lss_sync =
+ (caps_phy & SDHCI_UHS2_HOST_CAPS_PHY_N_LSS_SYN_MASK)
+ >> SDHCI_UHS2_HOST_CAPS_PHY_N_LSS_SYN_SHIFT;
+ mmc->uhs2_caps.n_lss_dir =
+ (caps_phy & SDHCI_UHS2_HOST_CAPS_PHY_N_LSS_DIR_MASK)
+ >> SDHCI_UHS2_HOST_CAPS_PHY_N_LSS_DIR_SHIFT;
+ if (mmc->uhs2_caps.n_lss_sync == 0)
+ mmc->uhs2_caps.n_lss_sync = 16 << 2;
+ else
+ mmc->uhs2_caps.n_lss_sync <<= 2;
+ if (mmc->uhs2_caps.n_lss_dir == 0)
+ mmc->uhs2_caps.n_lss_dir = 16 << 3;
+ else
+ mmc->uhs2_caps.n_lss_dir <<= 3;
+
+ /* LINK/TRAN Caps */
+ mmc->uhs2_caps.link_rev =
+ caps_tran[0] & SDHCI_UHS2_HOST_CAPS_TRAN_LINK_REV_MASK;
+ mmc->uhs2_caps.n_fcu =
+ (caps_tran[0] & SDHCI_UHS2_HOST_CAPS_TRAN_N_FCU_MASK)
+ >> SDHCI_UHS2_HOST_CAPS_TRAN_N_FCU_SHIFT;
+ if (mmc->uhs2_caps.n_fcu == 0)
+ mmc->uhs2_caps.n_fcu = 256;
+ mmc->uhs2_caps.host_type =
+ (caps_tran[0] & SDHCI_UHS2_HOST_CAPS_TRAN_HOST_TYPE_MASK)
+ >> SDHCI_UHS2_HOST_CAPS_TRAN_HOST_TYPE_SHIFT;
+ mmc->uhs2_caps.maxblk_len =
+ (caps_tran[0] & SDHCI_UHS2_HOST_CAPS_TRAN_BLK_LEN_MASK)
+ >> SDHCI_UHS2_HOST_CAPS_TRAN_BLK_LEN_SHIFT;
+ mmc->uhs2_caps.n_data_gap =
+ caps_tran[1] & SDHCI_UHS2_HOST_CAPS_TRAN_1_N_DATA_GAP_MASK;
+
+ return 0;
+}
+
+static int sdhci_uhs2_do_detect_init(struct mmc_host *mmc)
+{
+ struct sdhci_host *host = mmc_priv(mmc);
+ unsigned long flags;
+ int ret = -EIO;
+
+ DBG("%s: begin UHS2 init.\n", __func__);
+ spin_lock_irqsave(&host->lock, flags);
+
+ if (sdhci_uhs2_interface_detect(host)) {
+ pr_warn("%s: cannot detect UHS2 interface.\n",
+ mmc_hostname(host->mmc));
+ goto out;
+ }
+
+ if (sdhci_uhs2_init(host)) {
+ pr_warn("%s: UHS2 init fail.\n", mmc_hostname(host->mmc));
+ goto out;
+ }
+
+ /* Init complete, do soft reset and enable UHS2 error irqs. */
+ sdhci_uhs2_reset(host, SDHCI_UHS2_SW_RESET_SD);
+ sdhci_uhs2_clear_set_irqs(host, SDHCI_INT_ALL_MASK,
+ SDHCI_UHS2_ERR_INT_STATUS_MASK);
+ /*
+ * !!! SDHCI_INT_ENABLE and SDHCI_SIGNAL_ENABLE was cleared
+ * by SDHCI_UHS2_SW_RESET_SD
+ */
+ sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);
+ sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
+
+ ret = 0;
+out:
+ spin_unlock_irqrestore(&host->lock, flags);
+ return ret;
+}
+
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.set_ios = sdhci_uhs2_set_ios;

+ if (!host->mmc_host_ops.uhs2_detect_init)
+ host->mmc_host_ops.uhs2_detect_init = sdhci_uhs2_do_detect_init;
+
return 0;
}

--
2.28.0