linux-kernel - [PATCH 4/6] phy: meson-g12a-usb3-pcie: Add support for PCIe mode

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1567950178-4466-5-git-send-email-narmstrong@baylibre.com>
Date:   Sun,  8 Sep 2019 13:42:56 +0000
From:   Neil Armstrong <narmstrong@...libre.com>
To:     khilman@...libre.com, bhelgaas@...gle.com,
        lorenzo.pieralisi@....com, yue.wang@...ogic.com, kishon@...com
Cc:     repk@...plefau.lt, Neil Armstrong <narmstrong@...libre.com>,
        maz@...nel.org, linux-amlogic@...ts.infradead.org,
        linux-pci@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH 4/6] phy: meson-g12a-usb3-pcie: Add support for PCIe mode

This adds extended PCIe PHY functions for the Amlogic G12A
USB3+PCIE Combo PHY to support reset, power_on and power_off for
PCIe exclusively.

With these callbacks, we can handle all the needed operations of the
Amlogic PCIe controller driver.

Signed-off-by: Neil Armstrong <narmstrong@...libre.com>
---
 .../phy/amlogic/phy-meson-g12a-usb3-pcie.c    | 70 ++++++++++++++++---
 1 file changed, 61 insertions(+), 9 deletions(-)

diff --git a/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c b/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c
index ac322d643c7a..08e322789e59 100644
--- a/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c
+++ b/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c
@@ -50,6 +50,8 @@
 	#define PHY_R5_PHY_CR_ACK				BIT(16)
 	#define PHY_R5_PHY_BS_OUT				BIT(17)
 
+#define PCIE_RESET_DELAY					500
+
 struct phy_g12a_usb3_pcie_priv {
 	struct regmap		*regmap;
 	struct regmap		*regmap_cr;
@@ -196,6 +198,10 @@ static int phy_g12a_usb3_init(struct phy *phy)
 	struct phy_g12a_usb3_pcie_priv *priv = phy_get_drvdata(phy);
 	int data, ret;
 
+	ret = reset_control_reset(priv->reset);
+	if (ret)
+		return ret;
+
 	/* Switch PHY to USB3 */
 	/* TODO figure out how to handle when PCIe was set in the bootloader */
 	regmap_update_bits(priv->regmap, PHY_R0,
@@ -272,24 +278,64 @@ static int phy_g12a_usb3_init(struct phy *phy)
 	return 0;
 }
 
-static int phy_g12a_usb3_pcie_init(struct phy *phy)
+static int phy_g12a_usb3_pcie_power_on(struct phy *phy)
+{
+	struct phy_g12a_usb3_pcie_priv *priv = phy_get_drvdata(phy);
+
+	if (priv->mode == PHY_TYPE_USB3)
+		return 0;
+
+	regmap_update_bits(priv->regmap, PHY_R0,
+			   PHY_R0_PCIE_POWER_STATE,
+			   FIELD_PREP(PHY_R0_PCIE_POWER_STATE, 0x1c));
+
+	return 0;
+}
+
+static int phy_g12a_usb3_pcie_power_off(struct phy *phy)
+{
+	struct phy_g12a_usb3_pcie_priv *priv = phy_get_drvdata(phy);
+
+	if (priv->mode == PHY_TYPE_USB3)
+		return 0;
+
+	regmap_update_bits(priv->regmap, PHY_R0,
+			   PHY_R0_PCIE_POWER_STATE,
+			   FIELD_PREP(PHY_R0_PCIE_POWER_STATE, 0x1d));
+
+	return 0;
+}
+
+static int phy_g12a_usb3_pcie_reset(struct phy *phy)
 {
 	struct phy_g12a_usb3_pcie_priv *priv = phy_get_drvdata(phy);
 	int ret;
 
-	ret = reset_control_reset(priv->reset);
+	if (priv->mode == PHY_TYPE_USB3)
+		return 0;
+
+	ret = reset_control_assert(priv->reset);
 	if (ret)
 		return ret;
 
+	udelay(PCIE_RESET_DELAY);
+
+	ret = reset_control_deassert(priv->reset);
+	if (ret)
+		return ret;
+
+	udelay(PCIE_RESET_DELAY);
+
+	return 0;
+}
+
+static int phy_g12a_usb3_pcie_init(struct phy *phy)
+{
+	struct phy_g12a_usb3_pcie_priv *priv = phy_get_drvdata(phy);
+
 	if (priv->mode == PHY_TYPE_USB3)
 		return phy_g12a_usb3_init(phy);
 
-	/* Power UP PCIE */
-	/* TODO figure out when the bootloader has set USB3 mode before */
-	regmap_update_bits(priv->regmap, PHY_R0,
-			   PHY_R0_PCIE_POWER_STATE,
-			   FIELD_PREP(PHY_R0_PCIE_POWER_STATE, 0x1c));
-
 	return 0;
 }
 
@@ -297,7 +343,10 @@ static int phy_g12a_usb3_pcie_exit(struct phy *phy)
 {
 	struct phy_g12a_usb3_pcie_priv *priv = phy_get_drvdata(phy);
 
-	return reset_control_reset(priv->reset);
+	if (priv->mode == PHY_TYPE_USB3)
+		return reset_control_reset(priv->reset);
+
+	return 0;
 }
 
 static struct phy *phy_g12a_usb3_pcie_xlate(struct device *dev,
@@ -326,6 +375,9 @@ static struct phy *phy_g12a_usb3_pcie_xlate(struct device *dev,
 static const struct phy_ops phy_g12a_usb3_pcie_ops = {
 	.init		= phy_g12a_usb3_pcie_init,
 	.exit		= phy_g12a_usb3_pcie_exit,
+	.power_on	= phy_g12a_usb3_pcie_power_on,
+	.power_off	= phy_g12a_usb3_pcie_power_off,
+	.reset		= phy_g12a_usb3_pcie_reset,
 	.owner		= THIS_MODULE,
 };
 
-- 
2.17.1