xhci: workaround for AMD Promontory disabled ports wakeup

For AMD Promontory xHCI host, although you can disable USB ports in
BIOS settings, those ports will be enabled anyway after you remove a
device on that port and re-plug it in again. It's a known limitation of
the chip. As a workaround we can clear the PORT_WAKE_BITS.

[commit and code comment rephrasing -Mathias]
Signed-off-by: Joe Lee <asmt.swfae@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/pci-quirks.c

@@ -66,6 +66,23 @@
 #define	AX_INDXC		0x30
 #define	AX_DATAC		0x34
 
+#define PT_ADDR_INDX		0xE8
+#define PT_READ_INDX		0xE4
+#define PT_SIG_1_ADDR		0xA520
+#define PT_SIG_2_ADDR		0xA521
+#define PT_SIG_3_ADDR		0xA522
+#define PT_SIG_4_ADDR		0xA523
+#define PT_SIG_1_DATA		0x78
+#define PT_SIG_2_DATA		0x56
+#define PT_SIG_3_DATA		0x34
+#define PT_SIG_4_DATA		0x12
+#define PT4_P1_REG		0xB521
+#define PT4_P2_REG		0xB522
+#define PT2_P1_REG		0xD520
+#define PT2_P2_REG		0xD521
+#define PT1_P1_REG		0xD522
+#define PT1_P2_REG		0xD523
+
 #define	NB_PCIE_INDX_ADDR	0xe0
 #define	NB_PCIE_INDX_DATA	0xe4
 #define	PCIE_P_CNTL		0x10040
@@ -512,6 +529,98 @@ void usb_amd_dev_put(void)
 }
 EXPORT_SYMBOL_GPL(usb_amd_dev_put);
 
+/*
+ * Check if port is disabled in BIOS on AMD Promontory host.
+ * BIOS Disabled ports may wake on connect/disconnect and need
+ * driver workaround to keep them disabled.
+ * Returns true if port is marked disabled.
+ */
+bool usb_amd_pt_check_port(struct device *device, int port)
+{
+	unsigned char value, port_shift;
+	struct pci_dev *pdev;
+	u16 reg;
+
+	pdev = to_pci_dev(device);
+	pci_write_config_word(pdev, PT_ADDR_INDX, PT_SIG_1_ADDR);
+
+	pci_read_config_byte(pdev, PT_READ_INDX, &value);
+	if (value != PT_SIG_1_DATA)
+		return false;
+
+	pci_write_config_word(pdev, PT_ADDR_INDX, PT_SIG_2_ADDR);
+
+	pci_read_config_byte(pdev, PT_READ_INDX, &value);
+	if (value != PT_SIG_2_DATA)
+		return false;
+
+	pci_write_config_word(pdev, PT_ADDR_INDX, PT_SIG_3_ADDR);
+
+	pci_read_config_byte(pdev, PT_READ_INDX, &value);
+	if (value != PT_SIG_3_DATA)
+		return false;
+
+	pci_write_config_word(pdev, PT_ADDR_INDX, PT_SIG_4_ADDR);
+
+	pci_read_config_byte(pdev, PT_READ_INDX, &value);
+	if (value != PT_SIG_4_DATA)
+		return false;
+
+	/* Check disabled port setting, if bit is set port is enabled */
+	switch (pdev->device) {
+	case 0x43b9:
+	case 0x43ba:
+	/*
+	 * device is AMD_PROMONTORYA_4(0x43b9) or PROMONTORYA_3(0x43ba)
+	 * PT4_P1_REG bits[7..1] represents USB2.0 ports 6 to 0
+	 * PT4_P2_REG bits[6..0] represents ports 13 to 7
+	 */
+		if (port > 6) {
+			reg = PT4_P2_REG;
+			port_shift = port - 7;
+		} else {
+			reg = PT4_P1_REG;
+			port_shift = port + 1;
+		}
+		break;
+	case 0x43bb:
+	/*
+	 * device is AMD_PROMONTORYA_2(0x43bb)
+	 * PT2_P1_REG bits[7..5] represents USB2.0 ports 2 to 0
+	 * PT2_P2_REG bits[5..0] represents ports 9 to 3
+	 */
+		if (port > 2) {
+			reg = PT2_P2_REG;
+			port_shift = port - 3;
+		} else {
+			reg = PT2_P1_REG;
+			port_shift = port + 5;
+		}
+		break;
+	case 0x43bc:
+	/*
+	 * device is AMD_PROMONTORYA_1(0x43bc)
+	 * PT1_P1_REG[7..4] represents USB2.0 ports 3 to 0
+	 * PT1_P2_REG[5..0] represents ports 9 to 4
+	 */
+		if (port > 3) {
+			reg = PT1_P2_REG;
+			port_shift = port - 4;
+		} else {
+			reg = PT1_P1_REG;
+			port_shift = port + 4;
+		}
+		break;
+	default:
+		return false;
+	}
+	pci_write_config_word(pdev, PT_ADDR_INDX, reg);
+	pci_read_config_byte(pdev, PT_READ_INDX, &value);
+
+	return !(value & BIT(port_shift));
+}
+EXPORT_SYMBOL_GPL(usb_amd_pt_check_port);
+
 /*
  * Make sure the controller is completely inactive, unable to
  * generate interrupts or do DMA.

drivers/usb/host/pci-quirks.h

@@ -17,6 +17,7 @@ void usb_enable_intel_xhci_ports(struct pci_dev *xhci_pdev);
 void usb_disable_xhci_ports(struct pci_dev *xhci_pdev);
 void sb800_prefetch(struct device *dev, int on);
 bool usb_xhci_needs_pci_reset(struct pci_dev *pdev);
+bool usb_amd_pt_check_port(struct device *device, int port);
 #else
 struct pci_dev;
 static inline void usb_amd_quirk_pll_disable(void) {}
@@ -25,6 +26,10 @@ static inline void usb_asmedia_modifyflowcontrol(struct pci_dev *pdev) {}
 static inline void usb_amd_dev_put(void) {}
 static inline void usb_disable_xhci_ports(struct pci_dev *xhci_pdev) {}
 static inline void sb800_prefetch(struct device *dev, int on) {}
+static inline bool usb_amd_pt_check_port(struct device *device, int port)
+{
+	return false;
+}
 #endif  /* CONFIG_USB_PCI */
 
 #endif  /*  __LINUX_USB_PCI_QUIRKS_H  */

drivers/usb/host/xhci-hub.c

@@ -1522,6 +1522,13 @@ int xhci_bus_suspend(struct usb_hcd *hcd)
 				t2 |= PORT_WKOC_E | PORT_WKCONN_E;
 				t2 &= ~PORT_WKDISC_E;
 			}
+
+			if ((xhci->quirks & XHCI_U2_DISABLE_WAKE) &&
+			    (hcd->speed < HCD_USB3)) {
+				if (usb_amd_pt_check_port(hcd->self.controller,
+							  port_index))
+					t2 &= ~PORT_WAKE_BITS;
+			}
 		} else
 			t2 &= ~PORT_WAKE_BITS;
 

drivers/usb/host/xhci-pci.c

@@ -42,6 +42,10 @@
 #define PCI_DEVICE_ID_INTEL_APL_XHCI			0x5aa8
 #define PCI_DEVICE_ID_INTEL_DNV_XHCI			0x19d0
 
+#define PCI_DEVICE_ID_AMD_PROMONTORYA_4			0x43b9
+#define PCI_DEVICE_ID_AMD_PROMONTORYA_3			0x43ba
+#define PCI_DEVICE_ID_AMD_PROMONTORYA_2			0x43bb
+#define PCI_DEVICE_ID_AMD_PROMONTORYA_1			0x43bc
 #define PCI_DEVICE_ID_ASMEDIA_1042A_XHCI		0x1142
 
 static const char hcd_name[] = "xhci_hcd";
@@ -125,6 +129,13 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
 	if (pdev->vendor == PCI_VENDOR_ID_AMD)
 		xhci->quirks |= XHCI_TRUST_TX_LENGTH;
 
+	if ((pdev->vendor == PCI_VENDOR_ID_AMD) &&
+		((pdev->device == PCI_DEVICE_ID_AMD_PROMONTORYA_4) ||
+		(pdev->device == PCI_DEVICE_ID_AMD_PROMONTORYA_3) ||
+		(pdev->device == PCI_DEVICE_ID_AMD_PROMONTORYA_2) ||
+		(pdev->device == PCI_DEVICE_ID_AMD_PROMONTORYA_1)))
+		xhci->quirks |= XHCI_U2_DISABLE_WAKE;
+
 	if (pdev->vendor == PCI_VENDOR_ID_INTEL) {
 		xhci->quirks |= XHCI_LPM_SUPPORT;
 		xhci->quirks |= XHCI_INTEL_HOST;

drivers/usb/host/xhci.h

@@ -1822,7 +1822,7 @@ struct xhci_hcd {
 /* For controller with a broken Port Disable implementation */
 #define XHCI_BROKEN_PORT_PED	(1 << 25)
 #define XHCI_LIMIT_ENDPOINT_INTERVAL_7	(1 << 26)
-/* Reserved. It was XHCI_U2_DISABLE_WAKE */
+#define XHCI_U2_DISABLE_WAKE	(1 << 27)
 #define XHCI_ASMEDIA_MODIFY_FLOWCONTROL	(1 << 28)
 #define XHCI_HW_LPM_DISABLE	(1 << 29)