1 files changed, 64 insertions, 0 deletions
diff --git a/lib/acpi/mcfg.c b/lib/acpi/mcfg.c
new file mode 100644
index 0000000..7404ae58
--- /dev/null
+++ b/lib/acpi/mcfg.c
@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Write an ACPI MCFG table
+ *
+ * Copyright 2022 Google LLC
+ */
+
+#define LOG_CATEGORY LOGC_ACPI
+
+#include <common.h>
+#include <mapmem.h>
+#include <tables_csum.h>
+#include <acpi/acpi_table.h>
+#include <dm/acpi.h>
+
+int acpi_create_mcfg_mmconfig(struct acpi_mcfg_mmconfig *mmconfig, u32 base,
+			      u16 seg_nr, u8 start, u8 end)
+{
+	memset(mmconfig, 0, sizeof(*mmconfig));
+	mmconfig->base_address_l = base;
+	mmconfig->base_address_h = 0;
+	mmconfig->pci_segment_group_number = seg_nr;
+	mmconfig->start_bus_number = start;
+	mmconfig->end_bus_number = end;
+
+	return sizeof(struct acpi_mcfg_mmconfig);
+}
+
+__weak int acpi_fill_mcfg(struct acpi_ctx *ctx)
+{
+	return -ENOENT;
+}
+
+/* MCFG is defined in the PCI Firmware Specification 3.0 */
+int acpi_write_mcfg(struct acpi_ctx *ctx, const struct acpi_writer *entry)
+{
+	struct acpi_table_header *header;
+	struct acpi_mcfg *mcfg;
+	int ret;
+
+	mcfg = ctx->current;
+	header = &mcfg->header;
+
+	memset(mcfg, '\0', sizeof(struct acpi_mcfg));
+
+	/* Fill out header fields */
+	acpi_fill_header(header, "MCFG");
+	header->length = sizeof(struct acpi_mcfg);
+	header->revision = 1;
+	acpi_inc(ctx, sizeof(*mcfg));
+
+	ret = acpi_fill_mcfg(ctx);
+	if (ret)
+		return log_msg_ret("fill", ret);
+
+	/* (Re)calculate length and checksum */
+	header->length = (ulong)ctx->current - (ulong)mcfg;
+	header->checksum = table_compute_checksum(mcfg, header->length);
+
+	acpi_add_table(ctx, mcfg);
+
+	return 0;
+}
+ACPI_WRITER(5mcfg, "MCFG", acpi_write_mcfg, 0);