soc/intel/xeon_sp/cpx: search IIO_UDS HOB once when creating DMAR table

IIO_UDS HOB was searched several times during the creation of DMAR table.
Reduce it to only once to improve boot time.

Both DRHD and ATSR subtable creations involve addition of PCIe bridge
device entries, combine the functions with
acpi_create_dmar_ds_pci_br_for_port().

When looping through ports to create PCIe bridge device entries,
use MAX_PORTS intead of NUMBER_PORTS_PER_SOCKET to improve boot time.

Signed-off-by: Jonathan Zhang <jonzhang@fb.com>
Change-Id: I469cd8473c50e105daeda6c5607592ae7cef6032
Reviewed-on: https://review.coreboot.org/c/coreboot/+/45376
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Marc Jones <marc@marcjonesconsulting.com>

1 files changed, 60 insertions, 66 deletions

diff --git a/src/soc/intel/xeon_sp/cpx/acpi.c b/src/soc/intel/xeon_sp/cpx/acpi.c
index a40d33dcad..cd497c597b 100644
--- a/src/soc/intel/xeon_sp/cpx/acpi.c
+++ b/src/soc/intel/xeon_sp/cpx/acpi.c
@@ -586,19 +586,60 @@ static unsigned long acpi_fill_slit(unsigned long current)
  * 2A..2D   PSTACK1	stack 2     IOU2
  * 3A..3D   PSTACK2	stack 4     IOU3
  */
-static int get_stack_for_port(int p)
+static int get_stack_for_port(int port)
 {
-	if (p == 0)
+	if (port == PORT_0)
 		return CSTACK;
-	else if (p >= PORT_1A && p <= PORT_1D)
+	else if (port >= PORT_1A && port <= PORT_1D)
 		return PSTACK0;
-	else if (p >= PORT_2A && p <= PORT_2D)
+	else if (port >= PORT_2A && port <= PORT_2D)
 		return PSTACK1;
-	else //if (p >= PORT_3A && p <= PORT_3D)
+	else if (port >= PORT_3A && port <= PORT_3D)
 		return PSTACK2;
+	else
+		return -1;
 }
 
-static unsigned long acpi_create_drhd(unsigned long current, int socket, int stack)
+/*
+ * This function adds PCIe bridge device entry in DMAR table. If it is called
+ * in the context of ATSR subtable, it adds ATSR subtable when it is first called.
+ */
+static unsigned long acpi_create_dmar_ds_pci_br_for_port(unsigned long current,
+	int port, int stack, IIO_RESOURCE_INSTANCE iio_resource, uint32_t pcie_seg,
+	bool is_atsr, bool *first)
+{
+
+	if (get_stack_for_port(port) != stack)
+		return 0;
+
+	const uint32_t bus = iio_resource.StackRes[stack].BusBase;
+	const uint32_t dev = iio_resource.PcieInfo.PortInfo[port].Device;
+	const uint32_t func = iio_resource.PcieInfo.PortInfo[port].Function;
+
+	const uint32_t id = pci_mmio_read_config32(PCI_DEV(bus, dev, func),
+		PCI_VENDOR_ID);
+	if (id == 0xffffffff)
+		return 0;
+
+	unsigned long atsr_size = 0;
+	unsigned long pci_br_size = 0;
+	if (is_atsr == true && first && *first == true) {
+		printk(BIOS_DEBUG, "[Root Port ATS Capability] Flags: 0x%x, "
+			"PCI Segment Number: 0x%x\n", 0, pcie_seg);
+		atsr_size = acpi_create_dmar_atsr(current, 0, pcie_seg);
+		*first = false;
+	}
+
+	printk(BIOS_DEBUG, "    [PCI Bridge Device] Enumeration ID: 0x%x, "
+		"PCI Bus Number: 0x%x, PCI Path: 0x%x, 0x%x\n",
+		0, bus, dev, func);
+	pci_br_size = acpi_create_dmar_ds_pci_br(current + atsr_size, bus, dev, func);
+
+	return (atsr_size + pci_br_size);
+}
+
+static unsigned long acpi_create_drhd(unsigned long current, int socket,
+	int stack, const IIO_UDS *hob)
 {
 	int IoApicID[] = {
 		// socket 0
@@ -612,12 +653,6 @@ static unsigned long acpi_create_drhd(unsigned long current, int socket, int sta
 	uint32_t enum_id;
 	unsigned long tmp = current;
 
-	size_t hob_size;
-	const uint8_t fsp_hob_iio_universal_data_guid[16] = FSP_HOB_IIO_UNIVERSAL_DATA_GUID;
-	const IIO_UDS *hob = fsp_find_extension_hob_by_guid(
-		fsp_hob_iio_universal_data_guid, &hob_size);
-	assert(hob != NULL && hob_size != 0);
-
 	uint32_t bus = hob->PlatformData.IIO_resource[socket].StackRes[stack].BusBase;
 	uint32_t pcie_seg = hob->PlatformData.CpuQpiInfo[socket].PcieSegment;
 	uint32_t reg_base =
@@ -670,24 +705,9 @@ static unsigned long acpi_create_drhd(unsigned long current, int socket, int sta
 	if (socket != 0 || stack != CSTACK) {
 		IIO_RESOURCE_INSTANCE iio_resource =
 			hob->PlatformData.IIO_resource[socket];
-		for (int p = 0; p < NUMBER_PORTS_PER_SOCKET; ++p) {
-			if (get_stack_for_port(p) != stack)
-				continue;
-
-			uint32_t dev = iio_resource.PcieInfo.PortInfo[p].Device;
-			uint32_t func = iio_resource.PcieInfo.PortInfo[p].Function;
-
-			uint32_t id = pci_mmio_read_config32(PCI_DEV(bus, dev, func),
-				PCI_VENDOR_ID);
-			if (id == 0xffffffff)
-				continue;
-
-			printk(BIOS_DEBUG, "    [PCI Bridge Device] Enumeration ID: 0x%x, "
-				"PCI Bus Number: 0x%x, PCI Path: 0x%x, 0x%x\n",
-				0, bus, dev, func);
-			current += acpi_create_dmar_ds_pci_br(current,
-				bus, dev, func);
-		}
+		for (int p = PORT_0; p < MAX_PORTS; ++p)
+			current += acpi_create_dmar_ds_pci_br_for_port(current, p, stack,
+				iio_resource, pcie_seg, false, NULL);
 
 		// Add VMD
 		if (hob->PlatformData.VMDStackEnable[socket][stack] &&
@@ -722,13 +742,8 @@ static unsigned long acpi_create_drhd(unsigned long current, int socket, int sta
 	return current;
 }
 
-static unsigned long acpi_create_atsr(unsigned long current)
+static unsigned long acpi_create_atsr(unsigned long current, const IIO_UDS *hob)
 {
-	size_t hob_size;
-	const uint8_t uds_guid[16] = FSP_HOB_IIO_UNIVERSAL_DATA_GUID;
-	const IIO_UDS *hob = fsp_find_extension_hob_by_guid(uds_guid, &hob_size);
-	assert(hob != NULL && hob_size != 0);
-
 	for (int socket = 0; socket < hob->PlatformData.numofIIO; ++socket) {
 		uint32_t pcie_seg = hob->PlatformData.CpuQpiInfo[socket].PcieSegment;
 		unsigned long tmp = current;
@@ -752,32 +767,11 @@ static unsigned long acpi_create_atsr(unsigned long current)
 			if ((vtd_mmio_cap & 0x4) == 0) // BIT 2
 				continue;
 
-			for (int p = 0; p < NUMBER_PORTS_PER_SOCKET; ++p) {
-				if (socket == 0 && p == 0)
+			for (int p = PORT_0; p < MAX_PORTS; ++p) {
+				if (socket == 0 && p == PORT_0)
 					continue;
-				if (get_stack_for_port(p) != stack)
-					continue;
-
-				uint32_t dev = iio_resource.PcieInfo.PortInfo[p].Device;
-				uint32_t func = iio_resource.PcieInfo.PortInfo[p].Function;
-
-				u32 id = pci_mmio_read_config32(PCI_DEV(bus, dev, func),
-					PCI_VENDOR_ID);
-				if (id == 0xffffffff)
-					continue;
-
-				if (first) {
-					printk(BIOS_DEBUG, "[Root Port ATS Capability] Flags: 0x%x, "
-						"PCI Segment Number: 0x%x\n",
-						0, pcie_seg);
-					current += acpi_create_dmar_atsr(current, 0, pcie_seg);
-					first = 0;
-				}
-
-				printk(BIOS_DEBUG, "    [PCI Bridge Device] Enumeration ID: 0x%x, "
-					"PCI Bus Number: 0x%x, PCI Path: 0x%x, 0x%x\n",
-					0, bus, dev, func);
-				current += acpi_create_dmar_ds_pci_br(current, bus, dev, func);
+				current += acpi_create_dmar_ds_pci_br_for_port(current, p,
+					stack, iio_resource, pcie_seg, true, &first);
 			}
 		}
 		if (tmp != current)
@@ -858,19 +852,19 @@ static unsigned long acpi_fill_dmar(unsigned long current)
 
 		if (socket == 0) {
 			for (int stack = 1; stack <= PSTACK2; ++stack)
-				current = acpi_create_drhd(current, socket, stack);
-			current = acpi_create_drhd(current, socket, CSTACK);
+				current = acpi_create_drhd(current, socket, stack, hob);
+			current = acpi_create_drhd(current, socket, CSTACK, hob);
 		} else {
 			for (int stack = 0; stack <= PSTACK2; ++stack)
-				current = acpi_create_drhd(current, socket, stack);
+				current = acpi_create_drhd(current, socket, stack, hob);
 		}
 	}
 
 	// RMRR
 	current = acpi_create_rmrr(current);
 
-	// ATSR - causes hang
-	current = acpi_create_atsr(current);
+	// Root Port ATS Capability
+	current = acpi_create_atsr(current, hob);
 
 	// RHSA
 	current = acpi_create_rhsa(current);