From a35b6b09b90da7180e3c1321abb313d581f9530c Mon Sep 17 00:00:00 2001
From: Marvin Borner
Date: Sun, 6 Sep 2020 14:07:21 +0200
Subject: Added some ACPI tables

---
 kernel/drivers/acpi.c | 19 +++++++++++++++++++
 kernel/inc/acpi.h     | 40 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+)

diff --git a/kernel/drivers/acpi.c b/kernel/drivers/acpi.c
index 02f3718..f7f643c 100644
--- a/kernel/drivers/acpi.c
+++ b/kernel/drivers/acpi.c
@@ -44,6 +44,19 @@ struct rsdp *find_rsdp()
 	return NULL;
 }
 
+void *find_sdt(struct rsdt *rsdt, const char *signature)
+{
+	int entries = (rsdt->header.length - sizeof(rsdt->header)) / 4;
+
+	for (int i = 0; i < entries; i++) {
+		struct sdt_header *header = (struct sdt_header *)rsdt->sdt_pointer[i];
+		if (memcmp(header->signature, signature, 4) == 0)
+			return header;
+	}
+
+	return NULL;
+}
+
 void acpi_install()
 {
 	struct rsdp *rsdp = find_rsdp();
@@ -51,4 +64,10 @@ void acpi_install()
 	struct rsdt *rsdt = rsdp->rsdt;
 	assert(rsdt && memcmp(rsdt->header.signature, RSDT_MAGIC, 4) == 0 &&
 	       check_sdt(&rsdt->header));
+
+	madt = find_sdt(rsdt, MADT_MAGIC);
+	fadt = find_sdt(rsdt, FADT_MAGIC);
+	hpet = find_sdt(rsdt, HPET_MAGIC);
+	assert(madt && check_sdt(&madt->header) && fadt && check_sdt(&fadt->header) && hpet &&
+	       check_sdt(&hpet->header));
 }
diff --git a/kernel/inc/acpi.h b/kernel/inc/acpi.h
index f620d55..2b4c76e 100644
--- a/kernel/inc/acpi.h
+++ b/kernel/inc/acpi.h
@@ -7,6 +7,17 @@
 
 #define RSDP_MAGIC "RSD PTR "
 #define RSDT_MAGIC "RSDT"
+#define MADT_MAGIC "APIC"
+#define FADT_MAGIC "FACP"
+#define HPET_MAGIC "HPET"
+
+struct address_structure {
+	u8 address_space_id;
+	u8 register_bit_width;
+	u8 register_bit_offset;
+	u8 reserved;
+	u64 address;
+};
 
 struct sdt_header {
 	char signature[4];
@@ -32,11 +43,40 @@ struct rsdt {
 	u32 sdt_pointer[];
 };
 
+struct madt {
+	struct sdt_header header;
+	u32 local_address;
+	u32 flags;
+};
+
+struct fadt {
+	struct sdt_header header;
+	// TODO: FADT table (big!)
+};
+
+struct hpet {
+	struct sdt_header header;
+	u8 hardware_rev_id;
+	u8 comparator_count : 5;
+	u8 counter_size : 1;
+	u8 reserved : 1;
+	u8 legacy_replacement : 1;
+	u16 pci_vendor_id;
+	struct address_structure address;
+	u8 hpet_number;
+	u16 minimum_tick;
+	u8 page_protection;
+};
+
 struct rsdp {
 	struct sdp_header header;
 	struct rsdt *rsdt;
 };
 
+struct madt *madt;
+struct fadt *fadt;
+struct hpet *hpet;
+
 void acpi_install();
 
 #endif
-- 
cgit v1.2.3