USB: EHCI: Add Intel Moorestown EHCI controller HOSTPCx extensions and support phy low power mode

The Intel Moorestown EHCI controller supports non-standard HOSTPCx register
extension. This register controls the LPM behaviour and controls the behaviour
of each USB port.

Signed-off-by: Jacob Pan <[e-mail]>
Signed-off-by: Alek Du <[e-mail]>
Acked-by: Alan Stern <[e-mail]>
Cc: David Brownell <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/host/ehci-hcd.c

···
 	retval = handshake (ehci, &ehci->regs->command,
 			    CMD_RESET, 0, 250 * 1000);
 
+	if (ehci->has_hostpc) {
+		ehci_writel(ehci, USBMODE_EX_HC | USBMODE_EX_VBPS,
+			(u32 __iomem *)(((u8 *)ehci->regs) + USBMODE_EX));
+		ehci_writel(ehci, TXFIFO_DEFAULT,
+			(u32 __iomem *)(((u8 *)ehci->regs) + TXFILLTUNING));
+	}
 	if (retval)
 		return retval;
 

drivers/usb/host/ehci-hub.c

···
 	struct ehci_hcd		*ehci = hcd_to_ehci (hcd);
 	int			port;
 	int			mask;
+	u32 __iomem		*hostpc_reg = NULL;
 
 	ehci_dbg(ehci, "suspend root hub\n");
 
···
 		u32		t1 = ehci_readl(ehci, reg) & ~PORT_RWC_BITS;
 		u32		t2 = t1;
 
+		if (ehci->has_hostpc)
+			hostpc_reg = (u32 __iomem *)((u8 *)ehci->regs
+				+ HOSTPC0 + 4 * (port & 0xff));
 		/* keep track of which ports we suspend */
 		if (t1 & PORT_OWNER)
 			set_bit(port, &ehci->owned_ports);
···
 		}
 
 		/* enable remote wakeup on all ports */
-		if (hcd->self.root_hub->do_remote_wakeup)
-			t2 |= PORT_WAKE_BITS;
-		else
+		if (hcd->self.root_hub->do_remote_wakeup) {
+			/* only enable appropriate wake bits, otherwise the
+			 * hardware can not go phy low power mode. If a race
+			 * condition happens here(connection change during bits
+			 * set), the port change detection will finally fix it.
+			 */
+			if (t1 & PORT_CONNECT) {
+				t2 |= PORT_WKOC_E | PORT_WKDISC_E;
+				t2 &= ~PORT_WKCONN_E;
+			} else {
+				t2 |= PORT_WKOC_E | PORT_WKCONN_E;
+				t2 &= ~PORT_WKDISC_E;
+			}
+		} else
 			t2 &= ~PORT_WAKE_BITS;
 
 		if (t1 != t2) {
 			ehci_vdbg (ehci, "port %d, %08x -> %08x\n",
 				port + 1, t1, t2);
 			ehci_writel(ehci, t2, reg);
+			if (hostpc_reg) {
+				u32	t3;
+
+				msleep(5);/* 5ms for HCD enter low pwr mode */
+				t3 = ehci_readl(ehci, hostpc_reg);
+				ehci_writel(ehci, t3 | HOSTPC_PHCD, hostpc_reg);
+				t3 = ehci_readl(ehci, hostpc_reg);
+				ehci_dbg(ehci, "Port%d phy low pwr mode %s\n",
+					port, (t3 & HOSTPC_PHCD) ?
+					"succeeded" : "failed");
+			}
 		}
 	}
 
···
 	int		ports = HCS_N_PORTS (ehci->hcs_params);
 	u32 __iomem	*status_reg = &ehci->regs->port_status[
 				(wIndex & 0xff) - 1];
-	u32		temp, status;
+	u32 __iomem	*hostpc_reg = NULL;
+	u32		temp, temp1, status;
 	unsigned long	flags;
 	int		retval = 0;
 	unsigned	selector;
···
 	 * power, "this is the one", etc.  EHCI spec supports this.
 	 */
 
+	if (ehci->has_hostpc)
+		hostpc_reg = (u32 __iomem *)((u8 *)ehci->regs
+				+ HOSTPC0 + 4 * ((wIndex & 0xff) - 1));
 	spin_lock_irqsave (&ehci->lock, flags);
 	switch (typeReq) {
 	case ClearHubFeature:
···
 		if (temp & PORT_CONNECT) {
 			status |= 1 << USB_PORT_FEAT_CONNECTION;
 			// status may be from integrated TT
-			status |= ehci_port_speed(ehci, temp);
+			if (ehci->has_hostpc) {
+				temp1 = ehci_readl(ehci, hostpc_reg);
+				status |= ehci_port_speed(ehci, temp1);
+			} else
+				status |= ehci_port_speed(ehci, temp);
 		}
 		if (temp & PORT_PE)
 			status |= 1 << USB_PORT_FEAT_ENABLE;
···
 					|| (temp & PORT_RESET) != 0)
 				goto error;
 			ehci_writel(ehci, temp | PORT_SUSPEND, status_reg);
+			/* After above check the port must be connected.
+			 * Set appropriate bit thus could put phy into low power
+			 * mode if we have hostpc feature
+			 */
+			if (hostpc_reg) {
+				temp &= ~PORT_WKCONN_E;
+				temp |= (PORT_WKDISC_E | PORT_WKOC_E);
+				ehci_writel(ehci, temp | PORT_SUSPEND,
+							status_reg);
+				msleep(5);/* 5ms for HCD enter low pwr mode */
+				temp1 = ehci_readl(ehci, hostpc_reg);
+				ehci_writel(ehci, temp1 | HOSTPC_PHCD,
+					hostpc_reg);
+				temp1 = ehci_readl(ehci, hostpc_reg);
+				ehci_dbg(ehci, "Port%d phy low pwr mode %s\n",
+					wIndex, (temp1 & HOSTPC_PHCD) ?
+					"succeeded" : "failed");
+			}
 			set_bit(wIndex, &ehci->suspended_ports);
 			break;
 		case USB_PORT_FEAT_POWER:

drivers/usb/host/ehci.h

···
 	#define OHCI_HCCTRL_OFFSET      0x4
 	#define OHCI_HCCTRL_LEN         0x4
 	__hc32			*ohci_hcctrl_reg;
+	unsigned		has_hostpc:1;
 
 	u8			sbrn;		/* packed release number */
 
···
 ehci_port_speed(struct ehci_hcd *ehci, unsigned int portsc)
 {
 	if (ehci_is_TDI(ehci)) {
-		switch ((portsc>>26)&3) {
+		switch ((portsc >> (ehci->has_hostpc ? 25 : 26)) & 3) {
 		case 0:
 			return 0;
 		case 1:

include/linux/usb/ehci_def.h

···
 #define USBMODE_CM_HC	(3<<0)		/* host controller mode */
 #define USBMODE_CM_IDLE	(0<<0)		/* idle state */
 
+/* Moorestown has some non-standard registers, partially due to the fact that
+ * its EHCI controller has both TT and LPM support. HOSTPCx are extentions to
+ * PORTSCx
+ */
+#define HOSTPC0		0x84		/* HOSTPC extension */
+#define HOSTPC_PHCD	(1<<22)		/* Phy clock disable */
+#define HOSTPC_PSPD	(3<<25)		/* Port speed detection */
+#define USBMODE_EX	0xc8		/* USB Device mode extension */
+#define USBMODE_EX_VBPS	(1<<5)		/* VBus Power Select On */
+#define USBMODE_EX_HC	(3<<0)		/* host controller mode */
+#define TXFILLTUNING	0x24		/* TX FIFO Tuning register */
+#define TXFIFO_DEFAULT	(8<<16)		/* FIFO burst threshold 8 */
+
 /* Appendix C, Debug port ... intended for use with special "debug devices"
  * that can help if there's no serial console.  (nonstandard enumeration.)
  */