riscv: qemu: clear kernel-start/-end in device tree as workaround for BBL

QEMU specifies the location of Linux (supplied with the -kernel
argument) in the device tree using the riscv,kernel-start and
riscv,kernel-end properties. We currently rely on the SBI implementation
of BBL to run Linux and therefore embed Linux as payload in BBL. This
causes an issue, because BBL detects the kernel properties in the device
tree and ignores the Linux payload as a result.
Work around this issue by clearing the kernel properties in the device
tree before booting Linux.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
This commit is contained in:
Lukas Auer 2018-11-22 11:26:37 +01:00 committed by Andes
parent 66ffe5783b
commit 897206c5cc
2 changed files with 40 additions and 0 deletions

View File

@ -30,5 +30,6 @@ config BOARD_SPECIFIC_OPTIONS # dummy
imply CMD_EXT4
imply CMD_FAT
imply BOARD_LATE_INIT
imply OF_BOARD_SETUP
endif

View File

@ -48,3 +48,42 @@ int board_late_init(void)
return 0;
}
/*
* QEMU specifies the location of Linux (supplied with the -kernel argument)
* in the device tree using the riscv,kernel-start and riscv,kernel-end
* properties. We currently rely on the SBI implementation of BBL to run
* Linux and therefore embed Linux as payload in BBL. This causes an issue,
* because BBL detects the kernel properties in the device tree and ignores
* the Linux payload as a result. To work around this issue, we clear the
* kernel properties before booting Linux.
*
* This workaround can be removed, once we do not require BBL for its SBI
* implementation anymore.
*/
int ft_board_setup(void *blob, bd_t *bd)
{
int chosen_offset, ret;
chosen_offset = fdt_path_offset(blob, "/chosen");
if (chosen_offset < 0)
return 0;
#ifdef CONFIG_ARCH_RV64I
ret = fdt_setprop_u64(blob, chosen_offset, "riscv,kernel-start", 0);
#else
ret = fdt_setprop_u32(blob, chosen_offset, "riscv,kernel-start", 0);
#endif
if (ret)
return ret;
#ifdef CONFIG_ARCH_RV64I
ret = fdt_setprop_u64(blob, chosen_offset, "riscv,kernel-end", 0);
#else
ret = fdt_setprop_u32(blob, chosen_offset, "riscv,kernel-end", 0);
#endif
if (ret)
return ret;
return 0;
}