3 files changed, 87 insertions, 0 deletions

diff --git a/src/soc/intel/skylake/chip.h b/src/soc/intel/skylake/chip.h
index a9b8641626..57d51e76b2 100644
--- a/src/soc/intel/skylake/chip.h
+++ b/src/soc/intel/skylake/chip.h
@@ -35,6 +35,8 @@
 #include <soc/usb.h>
 #include <soc/vr_config.h>
 
+#define MAX_PEG_PORTS	3
+
 enum skylake_i2c_voltage {
 	I2C_VOLTAGE_3V3,
 	I2C_VOLTAGE_1V8
@@ -213,6 +215,28 @@ struct soc_intel_skylake_config {
 	 * respective PCIe root port.
 	 */
 
+	/* PEG Max Link Width */
+	enum {
+		Peg0_x16,
+		Peg0_x1,
+		Peg0_x2,
+		Peg0_x4,
+		Peg0_x8,
+	} Peg0MaxLinkWidth;
+
+	enum {
+		Peg1_x8,
+		Peg1_x1,
+		Peg1_x2,
+		Peg1_x4,
+	} Peg1MaxLinkWidth;
+
+	enum {
+		Peg2_x4,
+		Peg2_x1,
+		Peg2_x2,
+	} Peg2MaxLinkWidth;
+
 	/*
 	 * Enable/Disable Root Port
 	 * 0: Disable Root Port
diff --git a/src/soc/intel/skylake/include/soc/pci_devs.h b/src/soc/intel/skylake/include/soc/pci_devs.h
index f6957940e5..d59c80008b 100644
--- a/src/soc/intel/skylake/include/soc/pci_devs.h
+++ b/src/soc/intel/skylake/include/soc/pci_devs.h
@@ -37,6 +37,13 @@
 #define  SA_DEVFN_ROOT		_SA_DEVFN(ROOT)
 #define  SA_DEV_ROOT		_SA_DEV(ROOT)
 
+#define SA_DEV_SLOT_PEG		0x01
+#define  SA_DEVFN_PEG(func)	PCI_DEVFN(SA_DEV_SLOT_PEG, func)
+#define  SA_DEV_PEG(func)	dev_find_slot(0, SA_DEVFN_PEG(func))
+#define  SA_DEV_PEG0		SA_DEV_PEG(0)
+#define  SA_DEV_PEG1		SA_DEV_PEG(1)
+#define  SA_DEV_PEG2		SA_DEV_PEG(2)
+
 #define SA_DEV_SLOT_IGD		0x02
 #define  SA_DEVFN_IGD		_SA_DEVFN(IGD)
 #define  SA_DEV_IGD		_SA_DEV(IGD)
diff --git a/src/soc/intel/skylake/romstage/romstage_fsp20.c b/src/soc/intel/skylake/romstage/romstage_fsp20.c
index b65c9ff935..d9b2706a8b 100644
--- a/src/soc/intel/skylake/romstage/romstage_fsp20.c
+++ b/src/soc/intel/skylake/romstage/romstage_fsp20.c
@@ -202,6 +202,61 @@ static void cpu_flex_override(FSP_M_CONFIG *m_cfg)
 	m_cfg->CpuRatio = (flex_ratio.lo >> 8) & 0xff;
 }
 
+static void soc_peg_init_params(FSP_M_CONFIG *m_cfg,
+			FSP_M_TEST_CONFIG *m_t_cfg,
+			const struct soc_intel_skylake_config *config)
+{
+	const struct device *dev;
+	/*
+	 * To enable or disable the corresponding PEG root port you need to
+	 * add to the devicetree.cb:
+	 *
+	 *     device pci 01.0 on  end # enable PEG0 root port
+	 *     device pci 01.1 off end # do not configure PEG1
+	 *
+	 * If PEG port is not defined in the device tree, it will be disabled
+	 * in FSP
+	 */
+	dev = SA_DEV_PEG0; /* PEG 0:1:0 */
+	if (!dev || !dev->enabled)
+		m_cfg->Peg0Enable = 0;
+	else if (dev->enabled) {
+		m_cfg->Peg0Enable = dev->enabled;
+		m_cfg->Peg0MaxLinkWidth = config->Peg0MaxLinkWidth;
+		/* Use maximum possible link speed */
+		m_cfg->Peg0MaxLinkSpeed = 0;
+		/* Power down unused lanes based on the max possible width */
+		m_cfg->Peg0PowerDownUnusedLanes = 1;
+		/* Set [Auto] for options to enable equalization methods */
+		m_t_cfg->Peg0Gen3EqPh2Enable = 2;
+		m_t_cfg->Peg0Gen3EqPh3Method = 0;
+	}
+
+	dev = SA_DEV_PEG1; /* PEG 0:1:1 */
+	if (!dev || !dev->enabled)
+		m_cfg->Peg1Enable = 0;
+	else if (dev->enabled) {
+		m_cfg->Peg1Enable = dev->enabled;
+		m_cfg->Peg1MaxLinkWidth = config->Peg1MaxLinkWidth;
+		m_cfg->Peg1MaxLinkSpeed = 0;
+		m_cfg->Peg1PowerDownUnusedLanes = 1;
+		m_t_cfg->Peg1Gen3EqPh2Enable = 2;
+		m_t_cfg->Peg1Gen3EqPh3Method = 0;
+	}
+
+	dev = SA_DEV_PEG2; /* PEG 0:1:2 */
+	if (!dev || !dev->enabled)
+		m_cfg->Peg2Enable = 0;
+	else if (dev->enabled) {
+		m_cfg->Peg2Enable = dev->enabled;
+		m_cfg->Peg2MaxLinkWidth = config->Peg2MaxLinkWidth;
+		m_cfg->Peg2MaxLinkSpeed = 0;
+		m_cfg->Peg2PowerDownUnusedLanes = 1;
+		m_t_cfg->Peg2Gen3EqPh2Enable = 2;
+		m_t_cfg->Peg2Gen3EqPh3Method = 0;
+	}
+}
+
 static void soc_memory_init_params(FSP_M_CONFIG *m_cfg,
 			const struct soc_intel_skylake_config *config)
 {
@@ -276,6 +331,7 @@ void platform_fsp_memory_init_params_cb(FSPM_UPD *mupd, uint32_t version)
 	config = dev->chip_info;
 
 	soc_memory_init_params(m_cfg, config);
+	soc_peg_init_params(m_cfg, m_t_cfg, config);
 
 	/* Skip creating Management Engine MBP HOB */
 	m_t_cfg->SkipMbpHob = 0x01;