[PATCH v3 3/3] mmc: rtsx: Add SD Express mode support for RTS5261

From: rui_feng
Date: Wed Oct 28 2020 - 22:00:05 EST


From: Rui Feng <rui_feng@xxxxxxxxxxxxxx>

RTS5261 support SD mode and PCIe/NVMe mode. The workflow is as follows.
1.RTS5261 work in SD mode and set MMC_CAPS2_SD_EXP flag.
2.If card is plugged in, Host send CMD8 to ask card's PCIe availability.
3.If the card has PCIe availability and WP is not set, init_sd_express() will be invoked,
RTS5261 switch to PCIe/NVMe mode.
4.Mmc driver handover it to NVMe driver.
5.If card is unplugged, RTS5261 will switch to SD mode.

Signed-off-by: Rui Feng <rui_feng@xxxxxxxxxxxxxx>
---
v2:
1.re-enable mmc caps in sd_power_on()
2.don't check write protect bit in init_sd_express()
v3:
1.add comment write protect switch is needed
2.add host->eject = true in the end of init_sd_express()
---
drivers/mmc/host/rtsx_pci_sdmmc.c | 58 +++++++++++++++++++++++++++++++
1 file changed, 58 insertions(+)

diff --git a/drivers/mmc/host/rtsx_pci_sdmmc.c b/drivers/mmc/host/rtsx_pci_sdmmc.c
index 2763a376b054..3b6474cce703 100644
--- a/drivers/mmc/host/rtsx_pci_sdmmc.c
+++ b/drivers/mmc/host/rtsx_pci_sdmmc.c
@@ -895,7 +895,9 @@ static int sd_set_bus_width(struct realtek_pci_sdmmc *host,
static int sd_power_on(struct realtek_pci_sdmmc *host)
{
struct rtsx_pcr *pcr = host->pcr;
+ struct mmc_host *mmc = host->mmc;
int err;
+ u32 val;

if (host->power_state == SDMMC_POWER_ON)
return 0;
@@ -922,6 +924,21 @@ static int sd_power_on(struct realtek_pci_sdmmc *host)
if (err < 0)
return err;

+ if (PCI_PID(pcr) == PID_5261) {
+ if (pcr->extra_caps & EXTRA_CAPS_SD_EXPRESS)
+ mmc->caps2 |= MMC_CAP2_SD_EXP | MMC_CAP2_SD_EXP_1_2V;
+ /*
+ * HW read wp status when resuming from S3/S4,
+ * and then picks SD legacy interface if it's set
+ * in read-only mode.
+ */
+ val = rtsx_pci_readl(pcr, RTSX_BIPR);
+ if (val & SD_WRITE_PROTECT) {
+ pcr->extra_caps &= ~EXTRA_CAPS_SD_EXPRESS;
+ mmc->caps2 &= ~(MMC_CAP2_SD_EXP | MMC_CAP2_SD_EXP_1_2V);
+ }
+ }
+
host->power_state = SDMMC_POWER_ON;
return 0;
}
@@ -1308,6 +1325,44 @@ static int sdmmc_execute_tuning(struct mmc_host *mmc, u32 opcode)
return err;
}

+static int sdmmc_init_sd_express(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+ u32 relink_time;
+ struct realtek_pci_sdmmc *host = mmc_priv(mmc);
+ struct rtsx_pcr *pcr = host->pcr;
+
+ /* Set relink_time for changing to PCIe card */
+ relink_time = 0x8FFF;
+
+ rtsx_pci_write_register(pcr, 0xFF01, 0xFF, relink_time);
+ rtsx_pci_write_register(pcr, 0xFF02, 0xFF, relink_time >> 8);
+ rtsx_pci_write_register(pcr, 0xFF03, 0x01, relink_time >> 16);
+
+ rtsx_pci_write_register(pcr, PETXCFG, 0x80, 0x80);
+ rtsx_pci_write_register(pcr, LDO_VCC_CFG0,
+ RTS5261_LDO1_OCP_THD_MASK,
+ pcr->option.sd_800mA_ocp_thd);
+
+ if (pcr->ops->disable_auto_blink)
+ pcr->ops->disable_auto_blink(pcr);
+
+ /* For PCIe/NVMe mode can't enter delink issue */
+ pcr->hw_param.interrupt_en &= ~(SD_INT_EN);
+ rtsx_pci_writel(pcr, RTSX_BIER, pcr->hw_param.interrupt_en);
+
+ rtsx_pci_write_register(pcr, RTS5260_AUTOLOAD_CFG4,
+ RTS5261_AUX_CLK_16M_EN, RTS5261_AUX_CLK_16M_EN);
+ rtsx_pci_write_register(pcr, RTS5261_FW_CFG0,
+ RTS5261_FW_ENTER_EXPRESS, RTS5261_FW_ENTER_EXPRESS);
+ rtsx_pci_write_register(pcr, RTS5261_FW_CFG1,
+ RTS5261_MCU_BUS_SEL_MASK | RTS5261_MCU_CLOCK_SEL_MASK
+ | RTS5261_MCU_CLOCK_GATING | RTS5261_DRIVER_ENABLE_FW,
+ RTS5261_MCU_CLOCK_SEL_16M | RTS5261_MCU_CLOCK_GATING
+ | RTS5261_DRIVER_ENABLE_FW);
+ host->eject = true;
+ return 0;
+}
+
static const struct mmc_host_ops realtek_pci_sdmmc_ops = {
.pre_req = sdmmc_pre_req,
.post_req = sdmmc_post_req,
@@ -1317,6 +1372,7 @@ static const struct mmc_host_ops realtek_pci_sdmmc_ops = {
.get_cd = sdmmc_get_cd,
.start_signal_voltage_switch = sdmmc_switch_voltage,
.execute_tuning = sdmmc_execute_tuning,
+ .init_sd_express = sdmmc_init_sd_express,
};

static void init_extra_caps(struct realtek_pci_sdmmc *host)
@@ -1338,6 +1394,8 @@ static void init_extra_caps(struct realtek_pci_sdmmc *host)
mmc->caps |= MMC_CAP_8_BIT_DATA;
if (pcr->extra_caps & EXTRA_CAPS_NO_MMC)
mmc->caps2 |= MMC_CAP2_NO_MMC;
+ if (pcr->extra_caps & EXTRA_CAPS_SD_EXPRESS)
+ mmc->caps2 |= MMC_CAP2_SD_EXP | MMC_CAP2_SD_EXP_1_2V;
}

static void realtek_init_host(struct realtek_pci_sdmmc *host)
--
2.17.1