[U-Boot] [PATCH 2/5] x86: efi_loader: Build EFI memory map per E820 table

Bin Meng bmeng.cn at gmail.com
Sat Jun 23 10:03:48 UTC 2018


On x86 traditional E820 table is used to pass the memory information
to kernel. With EFI loader we can build the EFI memory map from it.

Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
---

 arch/x86/lib/e820.c | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/arch/x86/lib/e820.c b/arch/x86/lib/e820.c
index 9a9ec99..8b34f67 100644
--- a/arch/x86/lib/e820.c
+++ b/arch/x86/lib/e820.c
@@ -4,6 +4,7 @@
  */
 
 #include <common.h>
+#include <efi_loader.h>
 #include <asm/e820.h>
 
 DECLARE_GLOBAL_DATA_PTR;
@@ -34,3 +35,41 @@ __weak unsigned int install_e820_map(unsigned int max_entries,
 
 	return 4;
 }
+
+#if defined(CONFIG_EFI_LOADER) && !defined(CONFIG_SPL_BUILD)
+void efi_add_known_memory(void)
+{
+	struct e820_entry e820[E820MAX];
+	unsigned int i, num;
+	u64 start, pages;
+	int type;
+
+	num = install_e820_map(ARRAY_SIZE(e820), e820);
+
+	for (i = 0; i < num; ++i) {
+		start = e820[i].addr;
+		pages = ALIGN(e820[i].size, EFI_PAGE_SIZE) >> EFI_PAGE_SHIFT;
+
+		switch (e820[i].type) {
+		case E820_RAM:
+			type = EFI_CONVENTIONAL_MEMORY;
+			break;
+		case E820_RESERVED:
+			type = EFI_RESERVED_MEMORY_TYPE;
+			break;
+		case E820_ACPI:
+			type = EFI_ACPI_RECLAIM_MEMORY;
+			break;
+		case E820_NVS:
+			type = EFI_ACPI_MEMORY_NVS;
+			break;
+		case E820_UNUSABLE:
+		default:
+			type = EFI_UNUSABLE_MEMORY;
+			break;
+		}
+
+		efi_add_memory_map(start, pages, type, false);
+	}
+}
+#endif /* defined(EFI_LOADER) && !defined(CONFIG_SPL_BUILD) */
-- 
2.7.4



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