[PATCH 2/2] mmc: sdhci-pci-gli: GL9767: Fix initializing the UHS-II interface during a power-on

[Ben Chuang <benchuanggli@gmail.com>]

From: Ben Chuang <ben.chuang@genesyslogic.com.tw>

According to the power structure of IC hardware design for UHS-II
interface, reset control and timing must be added to the initialization
process of powering on the UHS-II interface.

Fixes: 27dd3b82557a ("mmc: sdhci-pci-gli: enable UHS-II mode for GL9767")
Cc: stable@vger.kernel.org # v6.13+
Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
---
 drivers/mmc/host/sdhci-pci-gli.c | 71 +++++++++++++++++++++++++++++++-
 1 file changed, 70 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-pci-gli.c b/drivers/mmc/host/sdhci-pci-gli.c
index 3a1de477e9af..85d0d7e6169c 100644
--- a/drivers/mmc/host/sdhci-pci-gli.c
+++ b/drivers/mmc/host/sdhci-pci-gli.c
@@ -283,6 +283,8 @@
 #define   PCIE_GLI_9767_UHS2_CTL2_ZC_VALUE	  0xb
 #define   PCIE_GLI_9767_UHS2_CTL2_ZC_CTL	  BIT(6)
 #define   PCIE_GLI_9767_UHS2_CTL2_ZC_CTL_VALUE	  0x1
+#define   PCIE_GLI_9767_UHS2_CTL2_FORCE_PHY_RESETN	BIT(13)
+#define   PCIE_GLI_9767_UHS2_CTL2_FORCE_RESETN_VALUE	BIT(14)
 
 #define GLI_MAX_TUNING_LOOP 40
 
@@ -1179,6 +1181,69 @@ static void gl9767_set_low_power_negotiation(struct pci_dev *pdev, bool enable)
 	gl9767_vhs_read(pdev);
 }
 
+static void sdhci_gl9767_uhs2_phy_reset_assert(struct sdhci_host *host)
+{
+	struct sdhci_pci_slot *slot = sdhci_priv(host);
+	struct pci_dev *pdev = slot->chip->pdev;
+	u32 value;
+
+	gl9767_vhs_write(pdev);
+	pci_read_config_dword(pdev, PCIE_GLI_9767_UHS2_CTL2, &value);
+	value |= PCIE_GLI_9767_UHS2_CTL2_FORCE_PHY_RESETN;
+	pci_write_config_dword(pdev, PCIE_GLI_9767_UHS2_CTL2, value);
+	value &= ~PCIE_GLI_9767_UHS2_CTL2_FORCE_RESETN_VALUE;
+	pci_write_config_dword(pdev, PCIE_GLI_9767_UHS2_CTL2, value);
+	gl9767_vhs_read(pdev);
+}
+
+static void sdhci_gl9767_uhs2_phy_reset_deassert(struct sdhci_host *host)
+{
+	struct sdhci_pci_slot *slot = sdhci_priv(host);
+	struct pci_dev *pdev = slot->chip->pdev;
+	u32 value;
+
+	gl9767_vhs_write(pdev);
+	pci_read_config_dword(pdev, PCIE_GLI_9767_UHS2_CTL2, &value);
+	value |= PCIE_GLI_9767_UHS2_CTL2_FORCE_RESETN_VALUE;
+	pci_write_config_dword(pdev, PCIE_GLI_9767_UHS2_CTL2, value);
+	value &= ~PCIE_GLI_9767_UHS2_CTL2_FORCE_PHY_RESETN;
+	pci_write_config_dword(pdev, PCIE_GLI_9767_UHS2_CTL2, value);
+	gl9767_vhs_read(pdev);
+}
+
+static void __gl9767_uhs2_set_power(struct sdhci_host *host, unsigned char mode, unsigned short vdd)
+{
+	u8 pwr = 0;
+
+	if (mode != MMC_POWER_OFF) {
+		pwr = sdhci_get_vdd_value(vdd);
+		if (!pwr)
+			WARN(1, "%s: Invalid vdd %#x\n",
+			     mmc_hostname(host->mmc), vdd);
+		pwr |= SDHCI_VDD2_POWER_180;
+	}
+
+	if (host->pwr == pwr)
+		return;
+
+	host->pwr = pwr;
+
+	if (pwr == 0) {
+		sdhci_writeb(host, 0, SDHCI_POWER_CONTROL);
+	} else {
+		sdhci_writeb(host, 0, SDHCI_POWER_CONTROL);
+
+		pwr |= SDHCI_POWER_ON;
+		sdhci_writeb(host, pwr & 0xf, SDHCI_POWER_CONTROL);
+		mdelay(5);
+
+		sdhci_gl9767_uhs2_phy_reset_assert(host);
+		pwr |= SDHCI_VDD2_POWER_ON;
+		sdhci_writeb(host, pwr, SDHCI_POWER_CONTROL);
+		mdelay(5);
+	}
+}
+
 static void sdhci_gl9767_set_clock(struct sdhci_host *host, unsigned int clock)
 {
 	struct sdhci_pci_slot *slot = sdhci_priv(host);
@@ -1205,6 +1270,10 @@ static void sdhci_gl9767_set_clock(struct sdhci_host *host, unsigned int clock)
 	}
 
 	sdhci_enable_clk(host, clk);
+
+	if (mmc_card_uhs2(host->mmc))
+		sdhci_gl9767_uhs2_phy_reset_deassert(host);
+
 	gl9767_set_low_power_negotiation(pdev, true);
 }
 
@@ -1476,7 +1545,7 @@ static void sdhci_gl9767_set_power(struct sdhci_host *host, unsigned char mode,
 		gl9767_vhs_read(pdev);
 
 		sdhci_gli_overcurrent_event_enable(host, false);
-		sdhci_uhs2_set_power(host, mode, vdd);
+		__gl9767_uhs2_set_power(host, mode, vdd);
 		sdhci_gli_overcurrent_event_enable(host, true);
 	} else {
 		gl9767_vhs_write(pdev);
-- 
2.51.0