[PATCH V10 15/23] mmc: sdhci-uhs2: add detect_init() to detect the interface

From: Victor Shih
Date: Fri Aug 18 2023 - 06:05:58 EST


From: Victor Shih <victor.shih@xxxxxxxxxxxxxxxxxxx>

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@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:
- usleep_range() to instead of udelay() in sdhci_uhs2_interface_detect().
- read_poll_timeout() to instead of read_poll_timeout_atomic()
in sdhci_uhs2_interface_detect().
- Modify return value in sdhci_uhs2_do_detect_init().

Updates in V7:
- Drop using uhs2_reset ops and use sdhci_uhs2_reset()
in sdhci_uhs2_do_detect_init().

Updates in V6:
- Remove unnecessary functions.
- Wrap at 100 columns in some functions.

---

drivers/mmc/host/sdhci-uhs2.c | 112 ++++++++++++++++++++++++++++++++++
1 file changed, 112 insertions(+)

diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
index ad791c48f681..4c2a56629ab3 100644
--- a/drivers/mmc/host/sdhci-uhs2.c
+++ b/drivers/mmc/host/sdhci-uhs2.c
@@ -335,6 +335,118 @@ static int sdhci_uhs2_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
* *
\*****************************************************************************/

+static int sdhci_uhs2_interface_detect(struct sdhci_host *host)
+{
+ int timeout = 100000; /* 100ms */
+ u32 val;
+
+ usleep_range(50, 200); /* wait for 50us - 200us before check */
+
+ if (read_poll_timeout(sdhci_readl, val, (val & SDHCI_UHS2_IF_DETECT),
+ 100, timeout, true, host, SDHCI_PRESENT_STATE)) {
+ pr_warn("%s: not detect UHS2 interface in 100ms.\n", mmc_hostname(host->mmc));
+ sdhci_dumpregs(host);
+ return -EIO;
+ }
+
+ /* Enable UHS2 error interrupts */
+ sdhci_uhs2_clear_set_irqs(host, SDHCI_INT_ALL_MASK, SDHCI_UHS2_INT_ERROR_MASK);
+
+ /* 150ms */
+ timeout = 150000;
+ if (read_poll_timeout(sdhci_readl, val, (val & SDHCI_UHS2_LANE_SYNC),
+ 100, timeout, true, host, SDHCI_PRESENT_STATE)) {
+ pr_warn("%s: UHS2 Lane sync fail in 150ms.\n", mmc_hostname(host->mmc));
+ sdhci_dumpregs(host);
+ return -EIO;
+ }
+
+ 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;
+
+ caps_ptr = sdhci_readw(host, SDHCI_UHS2_CAPS_PTR);
+ if (caps_ptr < 0x100 || caps_ptr > 0x1FF) {
+ pr_err("%s: SDHCI_UHS2_CAPS_PTR(%d) is wrong.\n",
+ mmc_hostname(mmc), caps_ptr);
+ return -ENODEV;
+ }
+ caps_gen = sdhci_readl(host, caps_ptr + SDHCI_UHS2_CAPS_OFFSET);
+ caps_phy = sdhci_readl(host, caps_ptr + SDHCI_UHS2_CAPS_PHY_OFFSET);
+ caps_tran[0] = sdhci_readl(host, caps_ptr + SDHCI_UHS2_CAPS_TRAN_OFFSET);
+ caps_tran[1] = sdhci_readl(host, caps_ptr + SDHCI_UHS2_CAPS_TRAN_1_OFFSET);
+
+ /* General Caps */
+ mmc->uhs2_caps.dap = caps_gen & SDHCI_UHS2_CAPS_DAP_MASK;
+ mmc->uhs2_caps.gap = FIELD_GET(SDHCI_UHS2_CAPS_GAP_MASK, caps_gen);
+ mmc->uhs2_caps.n_lanes = FIELD_GET(SDHCI_UHS2_CAPS_LANE_MASK, caps_gen);
+ mmc->uhs2_caps.addr64 = (caps_gen & SDHCI_UHS2_CAPS_ADDR_64) ? 1 : 0;
+ mmc->uhs2_caps.card_type = FIELD_GET(SDHCI_UHS2_CAPS_DEV_TYPE_MASK, caps_gen);
+
+ /* PHY Caps */
+ mmc->uhs2_caps.phy_rev = caps_phy & SDHCI_UHS2_CAPS_PHY_REV_MASK;
+ mmc->uhs2_caps.speed_range = FIELD_GET(SDHCI_UHS2_CAPS_PHY_RANGE_MASK, caps_phy);
+ mmc->uhs2_caps.n_lss_sync = FIELD_GET(SDHCI_UHS2_CAPS_PHY_N_LSS_SYN_MASK, caps_phy);
+ mmc->uhs2_caps.n_lss_dir = FIELD_GET(SDHCI_UHS2_CAPS_PHY_N_LSS_DIR_MASK, caps_phy);
+ 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_CAPS_TRAN_LINK_REV_MASK;
+ mmc->uhs2_caps.n_fcu = FIELD_GET(SDHCI_UHS2_CAPS_TRAN_N_FCU_MASK, caps_tran[0]);
+ if (mmc->uhs2_caps.n_fcu == 0)
+ mmc->uhs2_caps.n_fcu = 256;
+ mmc->uhs2_caps.host_type = FIELD_GET(SDHCI_UHS2_CAPS_TRAN_HOST_TYPE_MASK, caps_tran[0]);
+ mmc->uhs2_caps.maxblk_len = FIELD_GET(SDHCI_UHS2_CAPS_TRAN_BLK_LEN_MASK, caps_tran[0]);
+ mmc->uhs2_caps.n_data_gap = caps_tran[1] & SDHCI_UHS2_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);
+
+ DBG("Begin do uhs2 detect init.\n");
+
+ if (sdhci_uhs2_interface_detect(host)) {
+ pr_warn("%s: cannot detect UHS2 interface.\n", mmc_hostname(host->mmc));
+ return -EIO;
+ }
+
+ if (sdhci_uhs2_init(host)) {
+ pr_warn("%s: UHS2 init fail.\n", mmc_hostname(host->mmc));
+ return -EIO;
+ }
+
+ /* 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_INT_ERROR_MASK);
+ /*
+ * N.B 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);
+
+ return 0;
+}
+
static int sdhci_uhs2_host_ops_init(struct sdhci_host *host)
{
host->mmc_host_ops.start_signal_voltage_switch =
--
2.25.1