[PATCH V20 15/22] mmc: sdhci-uhs2: add uhs2_control() to initialise the interface

Victor Shih
2024-09-05T10:21:10Z

UHS-II interface (related registers) will be initialized here. The operations include mmc's
uhs2_set_reg operations, mmc's uhs2_detect_init operations, uhs2_[enable|disable]_clk operations,
uhs2_set_ios operations. After detected the UHS-II interface, 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>
Signed-off-by: Victor Shih <victor.shih@genesyslogic.com.tw>
---

Updates in V15:
- Resolve merge conflicts and reduce unnecessary line breaks.

Updates in V13:
- Merge Patch#15, Patch#16 and Patch#17 of v12 version into Patch#15 in v13 version.
- Use definitions to simplify code.
- Modify comment message.

---

drivers/mmc/host/sdhci-uhs2.c | 228 ++++++++++++++++++++++++++++++++++
1 file changed, 228 insertions(+)

diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
index abb56ab8f916..a521e3dbfca7 100644
--- a/drivers/mmc/host/sdhci-uhs2.c
+++ b/drivers/mmc/host/sdhci-uhs2.c
@@ -25,6 +25,9 @@
pr_err("%s: " DRIVER_NAME ": " f, mmc_hostname(host->mmc), ## x)

#define UHS2_RESET_TIMEOUT_100MS 100000
+#define UHS2_CHECK_DORMANT_TIMEOUT_100MS 100000
+#define UHS2_INTERFACE_DETECT_TIMEOUT_100MS 100000
+#define UHS2_LANE_SYNC_TIMEOUT_150MS 150000

void sdhci_uhs2_dump_regs(struct sdhci_host *host)
{
@@ -302,6 +305,229 @@ static int sdhci_uhs2_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
return 0;
}

+static int sdhci_uhs2_interface_detect(struct sdhci_host *host)
+{
+ u32 val;
+
+ if (read_poll_timeout(sdhci_readl, val, (val & SDHCI_UHS2_IF_DETECT),
+ 100, UHS2_INTERFACE_DETECT_TIMEOUT_100MS, 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);
+
+ if (read_poll_timeout(sdhci_readl, val, (val & SDHCI_UHS2_LANE_SYNC),
+ 100, UHS2_LANE_SYNC_TIMEOUT_150MS, 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_disable_clk(struct mmc_host *mmc)
+{
+ struct sdhci_host *host = mmc_priv(mmc);
+ u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+
+ clk &= ~SDHCI_CLOCK_CARD_EN;
+ sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+ return 0;
+}
+
+static int sdhci_uhs2_enable_clk(struct mmc_host *mmc)
+{
+ struct sdhci_host *host = mmc_priv(mmc);
+ u16 clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+ int timeout_us = 20000; /* 20ms */
+ u32 val;
+
+ clk |= SDHCI_CLOCK_CARD_EN;
+ sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+ if (read_poll_timeout(sdhci_readw, val, (val & SDHCI_CLOCK_INT_STABLE),
+ 10, timeout_us, true, host, SDHCI_CLOCK_CONTROL)) {
+ pr_err("%s: Internal clock never stabilised.\n", mmc_hostname(host->mmc));
+ sdhci_dumpregs(host);
+ return -EIO;
+ }
+ return 0;
+}
+
+static void sdhci_uhs2_set_config(struct sdhci_host *host)
+{
+ u32 value;
+ u16 sdhci_uhs2_set_ptr = sdhci_readw(host, SDHCI_UHS2_SETTINGS_PTR);
+ u16 sdhci_uhs2_gen_set_reg = sdhci_uhs2_set_ptr;
+ 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 */
+ value = FIELD_PREP(SDHCI_UHS2_GEN_SETTINGS_N_LANES_MASK, host->mmc->uhs2_caps.n_lanes_set);
+ sdhci_writel(host, value, sdhci_uhs2_gen_set_reg);
+
+ /* Set PHY Settings */
+ value = FIELD_PREP(SDHCI_UHS2_PHY_N_LSS_DIR_MASK, host->mmc->uhs2_caps.n_lss_dir_set) |
+ FIELD_PREP(SDHCI_UHS2_PHY_N_LSS_SYN_MASK, host->mmc->uhs2_caps.n_lss_sync_set);
+ if (host->mmc->ios.timing == MMC_TIMING_UHS2_SPEED_B ||
+ host->mmc->ios.timing == MMC_TIMING_UHS2_SPEED_B_HD)
+ value |= SDHCI_UHS2_PHY_SET_SPEED_B;
+ sdhci_writel(host, value, sdhci_uhs2_phy_set_reg);
+
+ /* Set LINK-TRAN Settings */
+ value = FIELD_PREP(SDHCI_UHS2_TRAN_RETRY_CNT_MASK, host->mmc->uhs2_caps.max_retry_set) |
+ FIELD_PREP(SDHCI_UHS2_TRAN_N_FCU_MASK, host->mmc->uhs2_caps.n_fcu_set);
+ 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)
+{
+ u32 val;
+
+ if (read_poll_timeout(sdhci_readl, val, (val & SDHCI_UHS2_IN_DORMANT_STATE),
+ 100, UHS2_CHECK_DORMANT_TIMEOUT_100MS, true, host,
+ SDHCI_PRESENT_STATE)) {
+ pr_warn("%s: UHS2 IN_DORMANT fail in 100ms.\n", mmc_hostname(host->mmc));
+ sdhci_dumpregs(host);
+ return -EIO;
+ }
+ return 0;
+}
+
+static int sdhci_uhs2_control(struct mmc_host *mmc, enum sd_uhs2_operation op)
+{
+ struct sdhci_host *host = mmc_priv(mmc);
+ struct mmc_ios *ios = &mmc->ios;
+ int err = 0;
+
+ DBG("Begin uhs2 control, act %d.\n", op);
+
+ switch (op) {
+ case UHS2_PHY_INIT:
+ err = sdhci_uhs2_do_detect_init(mmc);
+ break;
+ case UHS2_SET_CONFIG:
+ sdhci_uhs2_set_config(host);
+ break;
+ case UHS2_ENABLE_INT:
+ sdhci_uhs2_clear_set_irqs(host, 0, SDHCI_INT_CARD_INT);
+ break;
+ case UHS2_DISABLE_INT:
+ sdhci_uhs2_clear_set_irqs(host, SDHCI_INT_CARD_INT, 0);
+ break;
+ case UHS2_CHECK_DORMANT:
+ err = sdhci_uhs2_check_dormant(host);
+ break;
+ case UHS2_DISABLE_CLK:
+ err = sdhci_uhs2_disable_clk(mmc);
+ break;
+ case UHS2_ENABLE_CLK:
+ err = sdhci_uhs2_enable_clk(mmc);
+ break;
+ case UHS2_SET_IOS:
+ err = sdhci_uhs2_set_ios(mmc, ios);
+ break;
+ default:
+ pr_err("%s: input sd uhs2 operation %d is wrong!\n",
+ mmc_hostname(host->mmc), op);
+ err = -EIO;
+ break;
+ }
+
+ return err;
+}
+
/*****************************************************************************\
* *
* Driver init/exit *
@@ -310,6 +536,8 @@ static int sdhci_uhs2_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)

static int sdhci_uhs2_host_ops_init(struct sdhci_host *host)
{
+ host->mmc_host_ops.uhs2_control = sdhci_uhs2_control;
+
return 0;
}

--
2.25.1