UEFI and republicans

4 files changed, 176 insertions, 0 deletions

diff --git a/kernel/efi/efi.c b/kernel/efi/efi.c
new file mode 100644
index 0000000..4f253a7
--- /dev/null
+++ b/kernel/efi/efi.c
@@ -0,0 +1,28 @@
+#include "lib/klib.h"
+#include <lib.h>
+#include <comus/efi.h>
+#include <comus/mboot.h>
+#include <comus/memory.h>
+#include <efi.h>
+
+#include "efi.h"
+
+void efi_init(EFI_HANDLE IH, EFI_SYSTEM_TABLE *ST)
+{
+	EFI_STATUS status;
+
+	if (IH == NULL || ST == NULL)
+		return;
+
+	status = efi_load_mmap(ST);
+	if (EFI_ERROR(status))
+		panic("Failed to load efi memory map, EFI_STATUS = %lu\n", status);
+
+	status = efi_load_gop(ST);
+	if (EFI_ERROR(status))
+		panic(
+			"Failed to locate graphics output protocol (GOP), EFI_STATUS = %lu\n",
+			status);
+
+	ST->BootServices->ExitBootServices(IH, 0);
+}
diff --git a/kernel/efi/efi.h b/kernel/efi/efi.h
new file mode 100644
index 0000000..7428f37
--- /dev/null
+++ b/kernel/efi/efi.h
@@ -0,0 +1,9 @@
+#ifndef __EFI_H
+#define __EFI_H
+
+#include <efi.h>
+
+EFI_STATUS efi_load_mmap(EFI_SYSTEM_TABLE *ST);
+EFI_STATUS efi_load_gop(EFI_SYSTEM_TABLE *ST);
+
+#endif /* efi.h */
diff --git a/kernel/efi/gop.c b/kernel/efi/gop.c
new file mode 100644
index 0000000..899bbee
--- /dev/null
+++ b/kernel/efi/gop.c
@@ -0,0 +1,52 @@
+#include <lib.h>
+#include <efi.h>
+#include <comus/efi.h>
+
+static EFI_GRAPHICS_OUTPUT_PROTOCOL *gop = NULL;
+
+EFI_STATUS efi_load_gop(EFI_SYSTEM_TABLE *ST)
+{
+	EFI_STATUS status = EFI_SUCCESS;
+	EFI_GUID gopGuid = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
+	EFI_GRAPHICS_OUTPUT_MODE_INFORMATION *info;
+	UINTN SizeOfInfo, numModes, nativeMode;
+
+	status = ST->BootServices->LocateProtocol(&gopGuid, NULL, (void **)&gop);
+	if (EFI_ERROR(status))
+		return status;
+
+	status = gop->QueryMode(gop, gop->Mode == NULL ? 0 : gop->Mode->Mode,
+							&SizeOfInfo, &info);
+	if (status == EFI_NOT_STARTED)
+		status = gop->SetMode(gop, 0);
+	if (EFI_ERROR(status))
+		return status;
+
+	nativeMode = gop->Mode->Mode;
+	numModes = gop->Mode->MaxMode;
+
+	// find the best mode
+	UINTN best = nativeMode;
+	UINTN width = 0;
+	for (UINTN i = 0; i < numModes; i++) {
+		status = gop->QueryMode(gop, i, &SizeOfInfo, &info);
+		if (info->PixelFormat != PixelBlueGreenRedReserved8BitPerColor &&
+			info->PixelFormat != PixelRedGreenBlueReserved8BitPerColor)
+			continue;
+		if (info->HorizontalResolution > width) {
+			width = info->HorizontalResolution;
+			best = i;
+		}
+	}
+
+	gop->SetMode(gop, best);
+	if (EFI_ERROR(status))
+		return status;
+
+	return status;
+}
+
+EFI_GRAPHICS_OUTPUT_PROTOCOL *efi_get_gop(void)
+{
+	return gop;
+}
diff --git a/kernel/efi/mmap.c b/kernel/efi/mmap.c
new file mode 100644
index 0000000..26aba6a
--- /dev/null
+++ b/kernel/efi/mmap.c
@@ -0,0 +1,87 @@
+#include <lib.h>
+#include <efi.h>
+#include <comus/efi.h>
+#include <comus/memory.h>
+
+struct memory_map efi_mmap = { 0 };
+
+EFI_STATUS efi_load_mmap(EFI_SYSTEM_TABLE *ST)
+{
+	EFI_STATUS status = EFI_SUCCESS;
+
+	EFI_MEMORY_DESCRIPTOR *memory_map = NULL;
+	UINT32 version = 0;
+	UINTN map_key = 0;
+	UINTN descriptor_size = 0;
+	UINTN memory_map_size = 0;
+
+	status = ST->BootServices->GetMemoryMap(
+		&memory_map_size, memory_map, &map_key, &descriptor_size, &version);
+
+	assert(status != EFI_SUCCESS,
+		   "GetMemoryMap should NEVER succeed the first time");
+	if (status != EFI_BUFFER_TOO_SMALL)
+		return status;
+
+	UINTN encompassing_size = memory_map_size + (2 * descriptor_size);
+	void *buffer = NULL;
+	status = ST->BootServices->AllocatePool(EfiLoaderData, encompassing_size,
+											&buffer);
+
+	if (EFI_ERROR(status))
+		return status;
+
+	memory_map = (EFI_MEMORY_DESCRIPTOR *)buffer;
+	memory_map_size = encompassing_size;
+	status = ST->BootServices->GetMemoryMap(
+		&memory_map_size, memory_map, &map_key, &descriptor_size, &version);
+
+	if (EFI_ERROR(status))
+		return status;
+
+	uint32_t idx = 0;
+	for (size_t i = 0; i < (memory_map_size / descriptor_size); i++) {
+		EFI_MEMORY_DESCRIPTOR *seg =
+			(EFI_MEMORY_DESCRIPTOR *)((char *)memory_map +
+									  (descriptor_size * i));
+		if (idx >= N_MMAP_ENTRY)
+			panic("Too many mmap entries: limit is %d", N_MMAP_ENTRY);
+		efi_mmap.entries[idx].addr = seg->PhysicalStart;
+		efi_mmap.entries[idx].len = seg->NumberOfPages * PAGE_SIZE;
+		switch (seg->Type) {
+		case EfiReservedMemoryType:
+		case EfiMemoryMappedIO:
+		case EfiMemoryMappedIOPortSpace:
+			efi_mmap.entries[idx].type = SEG_TYPE_RESERVED;
+			break;
+		case EfiConventionalMemory:
+			efi_mmap.entries[idx].type = SEG_TYPE_FREE;
+			break;
+		case EfiACPIReclaimMemory:
+		case EfiACPIMemoryNVS:
+			efi_mmap.entries[idx].type = SEG_TYPE_ACPI;
+			break;
+		case EfiUnusableMemory:
+			efi_mmap.entries[idx].type = SEG_TYPE_DEFECTIVE;
+			break;
+		default:
+			efi_mmap.entries[idx].type = SEG_TYPE_EFI;
+			break;
+		}
+		idx++;
+	}
+	efi_mmap.entry_count = idx;
+
+	ST->BootServices->FreePool(buffer);
+
+	return status;
+}
+
+int efi_get_mmap(struct memory_map *map)
+{
+	if (efi_mmap.entry_count) {
+		*map = efi_mmap;
+		return 0;
+	}
+	return 1;
+}