efi: Add 64-bit payload support
Most EFI implementations use 64-bit. Add a way to build U-Boot as a 64-bit
EFI payload. The payload unpacks a (32-bit) U-Boot and starts it. This can
be enabled for x86 boards at present.
Signed-off-by: Simon Glass <sjg@chromium.org>
Improvements to how the payload is built:
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/lib/efi/efi_stub.c b/lib/efi/efi_stub.c
index 1e46f6e..d4d3e49 100644
--- a/lib/efi/efi_stub.c
+++ b/lib/efi/efi_stub.c
@@ -6,8 +6,8 @@
* EFI information obtained here:
* http://wiki.phoenix.com/wiki/index.php/EFI_BOOT_SERVICES
*
- * Loads a payload (U-Boot) within the EFI environment. This is built as a
- * 32-bit EFI application.
+ * Loads a payload (U-Boot) within the EFI environment. This is built as an
+ * EFI application. It can be built either in 32-bit or 64-bit mode.
*/
#include <common.h>
@@ -126,14 +126,16 @@
((func_t)addr)(0, 0, info);
#else
- /* TODO: Implement this */
+ cpu_call32(cs32, CONFIG_SYS_TEXT_BASE, info);
#endif
}
+#ifdef CONFIG_EFI_STUB_64BIT
static void get_gdt(struct desctab_info *info)
{
asm volatile ("sgdt %0" : : "m"(*info) : "memory");
}
+#endif
static inline unsigned long read_cr3(void)
{
@@ -156,7 +158,71 @@
{
int cs32 = 0;
- /* TODO(sjg): Implement this for 64-bit mode */
+#ifdef CONFIG_EFI_STUB_64BIT
+ struct desctab_info gdt;
+ uint64_t *ptr;
+ int i;
+
+ get_gdt(&gdt);
+ for (ptr = (uint64_t *)(unsigned long)gdt.addr, i = 0; i < gdt.limit;
+ i += 8, ptr++) {
+ uint64_t desc = *ptr;
+ uint64_t base, limit;
+
+ /*
+ * Check that the target U-Boot jump address is within the
+ * selector and that the selector is of the right type.
+ */
+ base = ((desc >> GDT_BASE_LOW_SHIFT) & GDT_BASE_LOW_MASK) |
+ ((desc >> GDT_BASE_HIGH_SHIFT) & GDT_BASE_HIGH_MASK)
+ << 16;
+ limit = ((desc >> GDT_LIMIT_LOW_SHIFT) & GDT_LIMIT_LOW_MASK) |
+ ((desc >> GDT_LIMIT_HIGH_SHIFT) & GDT_LIMIT_HIGH_MASK)
+ << 16;
+ base <<= 12; /* 4KB granularity */
+ limit <<= 12;
+ if ((desc & GDT_PRESENT) && (desc && GDT_NOTSYS) &&
+ !(desc & GDT_LONG) && (desc & GDT_4KB) &&
+ (desc & GDT_32BIT) && (desc & GDT_CODE) &&
+ CONFIG_SYS_TEXT_BASE > base &&
+ CONFIG_SYS_TEXT_BASE + CONFIG_SYS_MONITOR_LEN < limit
+ ) {
+ cs32 = i;
+ break;
+ }
+ }
+
+#ifdef DEBUG
+ puts("\ngdt: ");
+ printhex8(gdt.limit);
+ puts(", addr: ");
+ printhex8(gdt.addr >> 32);
+ printhex8(gdt.addr);
+ for (i = 0; i < gdt.limit; i += 8) {
+ uint32_t *ptr = (uint32_t *)((unsigned long)gdt.addr + i);
+
+ puts("\n");
+ printhex2(i);
+ puts(": ");
+ printhex8(ptr[1]);
+ puts(" ");
+ printhex8(ptr[0]);
+ }
+ puts("\n ");
+ puts("32-bit code segment: ");
+ printhex2(cs32);
+ puts("\n ");
+
+ puts("page_table: ");
+ printhex8(read_cr3());
+ puts("\n ");
+#endif
+ if (!cs32) {
+ puts("Can't find 32-bit code segment\n");
+ return -ENOENT;
+ }
+#endif
+
return cs32;
}