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efi_loader: allow compiling with clang

On ARM systems gd is stored in register r9 or x18. When compiling with
clang gd is defined as a macro calling function gd_ptr(). So we can not
make assignments to gd.

In the UEFI sub-system we need to save gd when leaving to UEFI binaries and
have to restore gd when reentering U-Boot.

Define a new function set_gd() for setting gd and use it in the UEFI
sub-system.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Tested-by: Tom Rini <trini@konsulko.com>
Heinrich Schuchardt 4 years ago
parent
commit
4f7dc5f608
2 changed files with 14 additions and 5 deletions
  1. 9 0
      arch/arm/include/asm/global_data.h
  2. 5 5
      lib/efi_loader/efi_boottime.c

+ 9 - 0
arch/arm/include/asm/global_data.h

@@ -117,4 +117,13 @@ static inline gd_t *get_gd(void)
 #endif
 #endif
 
+static inline void set_gd(volatile gd_t *gd_ptr)
+{
+#ifdef CONFIG_ARM64
+	__asm__ volatile("ldr x18, %0\n" : : "m"(gd_ptr));
+#else
+	__asm__ volatile("ldr r9, %0\n" : : "m"(gd_ptr));
+#endif
+}
+
 #endif /* __ASM_GBL_DATA_H */

+ 5 - 5
lib/efi_loader/efi_boottime.c

@@ -49,7 +49,7 @@ static efi_handle_t current_image;
  * restriction so we need to manually swap its and our view of that register on
  * EFI callback entry/exit.
  */
-static volatile void *efi_gd, *app_gd;
+static volatile gd_t *efi_gd, *app_gd;
 #endif
 
 /* 1 if inside U-Boot code, 0 if inside EFI payload code */
@@ -89,7 +89,7 @@ int __efi_entry_check(void)
 #ifdef CONFIG_ARM
 	assert(efi_gd);
 	app_gd = gd;
-	gd = efi_gd;
+	set_gd(efi_gd);
 #endif
 	return ret;
 }
@@ -99,7 +99,7 @@ int __efi_exit_check(void)
 {
 	int ret = --entry_count == 0;
 #ifdef CONFIG_ARM
-	gd = app_gd;
+	set_gd(app_gd);
 #endif
 	return ret;
 }
@@ -123,7 +123,7 @@ void efi_restore_gd(void)
 	/* Only restore if we're already in EFI context */
 	if (!efi_gd)
 		return;
-	gd = efi_gd;
+	set_gd(efi_gd);
 #endif
 }
 
@@ -2920,7 +2920,7 @@ efi_status_t EFIAPI efi_start_image(efi_handle_t image_handle,
 		 * otherwise __efi_entry_check() will put the wrong value into
 		 * app_gd.
 		 */
-		gd = app_gd;
+		set_gd(app_gd);
 #endif
 		/*
 		 * To get ready to call EFI_EXIT below we have to execute the