spl: support booting via RISC-V OpenSBI
RISC-V OpenSBI is an open-source implementation of the RISC-V Supervisor
Binary Interface (SBI) specification. It is required by Linux and U-Boot
running in supervisor mode. This patch adds support for booting via the
OpenSBI FW_DYNAMIC firmware. It supports OpenSBI version 0.4 and higher.
In this configuration, U-Boot SPL starts in machine mode. After loading
OpenSBI and U-Boot proper, it will start OpenSBI. All necessary
parameters are generated by U-Boot SPL and are passed to OpenSBI. U-Boot
proper is started in supervisor mode by OpenSBI. Support for OpenSBI is
enabled with CONFIG_SPL_OPENSBI. An additional configuration entry,
CONFIG_SPL_OPENSBI_LOAD_ADDR, is used to specify the load address of the
OpenSBI firmware binary. It is not used directly in U-Boot and instead
is intended to make the value available to scripts such as FIT
configuration generators.
The header file include/opensbi.h is based on header files from the
OpenSBI project. They are recent, as of commit bae54f764570 ("firmware:
Add fw_dynamic firmware").
Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
diff --git a/common/spl/spl.c b/common/spl/spl.c
index 2c696f2..8c9415b 100644
--- a/common/spl/spl.c
+++ b/common/spl/spl.c
@@ -659,6 +659,12 @@
(void *)spl_image.entry_point);
break;
#endif
+#if CONFIG_IS_ENABLED(OPENSBI)
+ case IH_OS_OPENSBI:
+ debug("Jumping to U-Boot via RISC-V OpenSBI\n");
+ spl_invoke_opensbi(&spl_image);
+ break;
+#endif
#ifdef CONFIG_SPL_OS_BOOT
case IH_OS_LINUX:
debug("Jumping to Linux\n");