[coreboot-gerrit] Change in coreboot[master]: soc/intel/skylake: Add USB port number information to wake s...

[Furquan Shaikh (Code Review)]

Furquan Shaikh has uploaded this change for review. ( https://review.coreboot.org/20122

Change subject: soc/intel/skylake: Add USB port number information to wake source
......................................................................

soc/intel/skylake: Add USB port number information to wake source

USB port status register can be used to decide if a particular port
was responsible for generating PME# resulting in device wake:
1. CCS bit is set and port is capable of waking on connect/disconnect
2. PLC bit is set and port is in resume state

BUG=b:37088992
TEST=Verified with wake on USB2.0 port 3, mosys shows:

19 | 2017-06-08 15:43:30 | Wake Source | PME - XHCI (USB 2.0 port) | 3

Change-Id: Ie4fa87393d8f096c4b3dca5f7a97f194cb065468
Signed-off-by: Furquan Shaikh 
---
M src/soc/intel/skylake/elog.c
1 file changed, 120 insertions(+), 1 deletion(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/22/20122/1

diff --git a/src/soc/intel/skylake/elog.c b/src/soc/intel/skylake/elog.c
index d127fcc..4cdcd2c 100644
--- a/src/soc/intel/skylake/elog.c
+++ b/src/soc/intel/skylake/elog.c
@@ -23,6 +23,7 @@
 #include <soc/pci_devs.h>
 #include <soc/pm.h>
 #include <soc/smbus.h>
+#include <stdint.h>

static void pch_log_gpio_gpe(u32 gpe0_sts, u32 gpe0_en, int start)
 {
@@ -36,6 +37,112 @@
    }
 }

+#define XHCI_USB2_PORT_STATUS_REG	0x480
+#define XHCI_USB3_PORT_STATUS_REG	0x540
+#define XHCI_USB2_PORT_NUM		10
+#define XHCI_USB3_PORT_NUM		6
+/* Wake on disconnect enable */
+#define XHCI_STATUS_WDE		(1 << 26)
+/* Wake on connect enable */
+#define XHCI_STATUS_WCE		(1 << 25)
+/* Port link status change */
+#define XHCI_STATUS_PLC		(1 << 22)
+/* Connect status change */
+#define XHCI_STATUS_CSC		(1 << 17)
+/* Port link status */
+#define XHCI_STATUS_PLS_SHIFT		(5)
+#define XHCI_STATUS_PLS_MASK		(0xF << XHCI_STATUS_PLS_SHIFT)
+#define XHCI_STATUS_PLS_RESUME		(15 << XHCI_STATUS_PLS_SHIFT)
+
+static bool pch_xhci_csc_set(uint32_t port_status)
+{
+	return !!(port_status & XHCI_STATUS_CSC);
+}
+
+static bool pch_xhci_wake_capable(uint32_t port_status)
+{
+	return (port_status & XHCI_STATUS_WCE) |
+		(port_status & XHCI_STATUS_WDE);
+}
+
+static bool pch_xhci_plc_set(uint32_t port_status)
+{
+	return !!(port_status & XHCI_STATUS_PLC);
+}
+
+static bool pch_xhci_resume(uint32_t port_status)
+{
+	return (port_status & XHCI_STATUS_PLS_MASK) == XHCI_STATUS_PLS_RESUME;
+}
+
+/*
+ * Check if a particular USB port caused wake by:
+ * 1. Change in connect/disconnect status (if enabled)
+ * 2. USB device activity
+ *
+ * Return value:
+ * 0 = None of the ports caused a wake
+ * n = Port number that caused the wake
+ */
+static uint32_t pch_xhci_port_wake_check(uintptr_t base, uint8_t num)
+{
+	uint8_t i;
+	uint32_t port_status;
+
+	for (i = 0; i < num; i++, base += 0x10) {
+		/* Read port status and control register for the port. */
+		port_status = read32((void *)base);
+
+		/*
+		 * Check if CSC bit is set and port is capable of wake on
+		 * connect/disconnect to identify if the port caused wake
+		 * event for usb attach/detach.
+		 */
+		if (pch_xhci_csc_set(port_status) &&
+		    pch_xhci_wake_capable(port_status))
+			return i + 1;
+
+		/*
+		 * Check if PLC is set and PLS indicates resume to identify if
+		 * the port caused wake event for usb activity.
+		 */
+		if (pch_xhci_plc_set(port_status) &&
+		    pch_xhci_resume(port_status))
+			return i + 1;
+	}
+	return 0;
+}
+
+/*
+ * Update elog event and instance depending upon the USB2/USB3 port that caused
+ * the wake event.
+ */
+static void pch_xhci_update_wake_event(device_t dev, uint32_t *event,
+					uint32_t *instance)
+{
+	uintptr_t mmio_base;
+
+	mmio_base = ALIGN_DOWN(pci_read_config32(dev, PCI_BASE_ADDRESS_0), 16);
+
+	/* USB2 ports */
+	*instance = pch_xhci_port_wake_check(mmio_base +
+					     XHCI_USB2_PORT_STATUS_REG,
+					     XHCI_USB2_PORT_NUM);
+
+	if (*instance) {
+		*event = ELOG_WAKE_SOURCE_PME_XHCI_USB_2;
+		return;
+	}
+
+	/* USB3 ports */
+	*instance = pch_xhci_port_wake_check(mmio_base +
+					     XHCI_USB3_PORT_STATUS_REG,
+					     XHCI_USB3_PORT_NUM);
+
+	if (*instance)
+		*event = ELOG_WAKE_SOURCE_PME_XHCI_USB_3;
+}
+
 struct pme_status_info {
    int devfn;
    uint8_t reg_offset;
@@ -43,6 +150,18 @@
 };

#define PME_STS_BIT		(1 << 15)
+
+static void pch_log_add_elog_event(const struct pme_status_info *info,
+					device_t dev)
+{
+	uint32_t instance = 0;
+	uint32_t event = info->elog_event;
+
+	if (info->devfn == PCH_DEVFN_XHCI)
+		pch_xhci_update_wake_event(dev, &event, &instance);
+
+	elog_add_event_wake(event, instance);
+}

static void pch_log_pme_internal_wake_source(void)
 {
@@ -87,7 +206,7 @@
    	if ((val == 0xFFFF) || !(val & PME_STS_BIT))
    		continue;

-		elog_add_event_wake(pme_status_info[i].elog_event, 0);
+		pch_log_add_elog_event(&pme_status_info[i], dev);
    	dev_found = true;
    }