[PATCH v5 05/11] RISC-V: Add early startup code

[Alexander Graf]

On entry, we need to save the system table pointer as well as our image
handle. Add an early startup file that saves them and then brings us
into our main function.

Signed-off-by: Alexander Graf <address@hidden>
Reviewed-by: Alistair Francis <address@hidden>
Reviewed-by: Bin Meng <address@hidden>
Tested-by: Bin Meng <address@hidden>
Reviewed-by: Daniel Kiper <address@hidden>

---

v3 -> v4:

  - Change copyright from 2013 to 2018

v4 -> v5:

  - Remove blank line at EOF
---
 grub-core/kern/riscv/efi/startup.S | 48 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)
 create mode 100644 grub-core/kern/riscv/efi/startup.S

diff --git a/grub-core/kern/riscv/efi/startup.S 
b/grub-core/kern/riscv/efi/startup.S
new file mode 100644
index 000000000..f2a7b2b1e
--- /dev/null
+++ b/grub-core/kern/riscv/efi/startup.S
@@ -0,0 +1,48 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2018  Free Software Foundation, Inc.
+ *
+ *  GRUB is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/symbol.h>
+
+#if __riscv_xlen == 64
+#define sl             sd
+#define ll             ld
+#else
+#define sl             sw
+#define ll             lw
+#endif
+
+
+       .file   "startup.S"
+       .text
+FUNCTION(_start)
+       /*
+        *  EFI_SYSTEM_TABLE and EFI_HANDLE are passed in a1/a0.
+        */
+
+       ll      a2, efi_image_handle_val
+       sl      a0, 0(a2)
+       ll      a2, efi_system_table_val
+       sl      a1, 0(a2)
+       ll      a2, grub_main_val
+       jr      a2
+grub_main_val:
+       .quad   EXT_C(grub_main)
+efi_system_table_val:
+       .quad   EXT_C(grub_efi_system_table)
+efi_image_handle_val:
+       .quad   EXT_C(grub_efi_image_handle)
-- 
2.12.3