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>

1 files changed, 109 insertions, 0 deletions

diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
index 161536717025..67ad4bb6919a 100644
--- a/drivers/usb/host/pci-quirks.c
+++ b/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
@@ -513,6 +530,98 @@ 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.
  */