[U-Boot] [PATCH v2 28/29] riscv: qemu: detect and boot the kernel passed by QEMU

Auer, Lukas lukas.auer at aisec.fraunhofer.de
Tue Oct 30 17:13:21 UTC 2018


On Tue, 2018-10-30 at 16:27 +0100, Alexander Graf wrote:
> 
> On 30.10.18 16:02, Auer, Lukas wrote:
> > On Tue, 2018-10-30 at 13:55 +0100, Lukas Auer wrote:
> > > QEMU embeds the location of the kernel image in the device tree.
> > > Store
> > > this address in the environment as variable kernel_start and use
> > > it
> > > in
> > > CONFIG_BOOTCOMMAND to boot the kernel. Use the device tree passed
> > > by
> > > the
> > > prior boot stage to boot Linux.
> > > 
> > > Signed-off-by: Lukas Auer <lukas.auer at aisec.fraunhofer.de>
> > > ---
> > > 
> > > Changes in v2:
> > > - Rebase onto u-boot-dm/next
> > > - Boot Linux with the device tree provided by the prior boot
> > > stage
> > > 
> > >  board/emulation/qemu-riscv/Kconfig      |  1 +
> > >  board/emulation/qemu-riscv/qemu-riscv.c | 29
> > > +++++++++++++++++++++++++
> > >  configs/qemu-riscv32_defconfig          |  1 +
> > >  configs/qemu-riscv64_defconfig          |  1 +
> > >  include/configs/qemu-riscv.h            | 10 ++++++++-
> > >  5 files changed, 41 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/board/emulation/qemu-riscv/Kconfig
> > > b/board/emulation/qemu-riscv/Kconfig
> > > index 37a80db6a9..be5839b7db 100644
> > > --- a/board/emulation/qemu-riscv/Kconfig
> > > +++ b/board/emulation/qemu-riscv/Kconfig
> > > @@ -29,5 +29,6 @@ config BOARD_SPECIFIC_OPTIONS # dummy
> > >  	imply CMD_EXT2
> > >  	imply CMD_EXT4
> > >  	imply CMD_FAT
> > > +	imply BOARD_LATE_INIT
> > >  
> > >  endif
> > > diff --git a/board/emulation/qemu-riscv/qemu-riscv.c
> > > b/board/emulation/qemu-riscv/qemu-riscv.c
> > > index 2ce093e19a..ee20983095 100644
> > > --- a/board/emulation/qemu-riscv/qemu-riscv.c
> > > +++ b/board/emulation/qemu-riscv/qemu-riscv.c
> > > @@ -19,3 +19,32 @@ int board_init(void)
> > >  
> > >  	return 0;
> > >  }
> > > +
> > > +int board_late_init(void)
> > > +{
> > > +	ulong kernel_start;
> > > +	ofnode chosen_node;
> > > +	int ret;
> > > +
> > > +	chosen_node = ofnode_path("/chosen");
> > > +	if (!ofnode_valid(chosen_node)) {
> > > +		printf("No chosen node found\n");
> > > +		return 0;
> > > +	}
> > > +
> > > +#ifdef CONFIG_ARCH_RV64I
> > > +	ret = ofnode_read_u64(chosen_node, "riscv,kernel-start",
> > > +			      (u64 *)&kernel_start);
> > > +#else
> > > +	ret = ofnode_read_u32(chosen_node, "riscv,kernel-start",
> > > +			      (u32 *)&kernel_start);
> > > +#endif
> > > +	if (ret) {
> > > +		printf("Can't find kernel start address in device
> > > tree\n");
> > > +		return 0;
> > > +	}
> > > +
> > > +	env_set_hex("kernel_start", kernel_start);
> > > +
> > > +	return 0;
> > > +}
> > > diff --git a/configs/qemu-riscv32_defconfig b/configs/qemu-
> > > riscv32_defconfig
> > > index b55644378a..13dd53a550 100644
> > > --- a/configs/qemu-riscv32_defconfig
> > > +++ b/configs/qemu-riscv32_defconfig
> > > @@ -4,4 +4,5 @@ CONFIG_NR_DRAM_BANKS=1
> > >  CONFIG_FIT=y
> > >  CONFIG_DISPLAY_CPUINFO=y
> > >  CONFIG_DISPLAY_BOARDINFO=y
> > > +CONFIG_HUSH_PARSER=y
> > >  CONFIG_OF_PRIOR_STAGE=y
> > > diff --git a/configs/qemu-riscv64_defconfig b/configs/qemu-
> > > riscv64_defconfig
> > > index a542ac4893..06eb3042fa 100644
> > > --- a/configs/qemu-riscv64_defconfig
> > > +++ b/configs/qemu-riscv64_defconfig
> > > @@ -5,4 +5,5 @@ CONFIG_NR_DRAM_BANKS=1
> > >  CONFIG_FIT=y
> > >  CONFIG_DISPLAY_CPUINFO=y
> > >  CONFIG_DISPLAY_BOARDINFO=y
> > > +CONFIG_HUSH_PARSER=y
> > >  CONFIG_OF_PRIOR_STAGE=y
> > > diff --git a/include/configs/qemu-riscv.h b/include/configs/qemu-
> > > riscv.h
> > > index ba6a18f2e6..7c88ba300a 100644
> > > --- a/include/configs/qemu-riscv.h
> > > +++ b/include/configs/qemu-riscv.h
> > > @@ -21,7 +21,15 @@
> > >  #define CONFIG_ENV_SIZE			SZ_4K
> > >  
> > >  #define CONFIG_EXTRA_ENV_SETTINGS \
> > > -	"fdt_high=0xffffffffffffffff\0" \
> > > +	"fdt_high=0x82000000\0" \
> > > +	"bootm_size=0x10000000\0" \
> > >  	"initrd_high=0xffffffffffffffff\0"
> > >  
> > > +#define CONFIG_BOOTCOMMAND \
> > > +	"if env exists kernel_start; then " \
> > > +		"bootm ${kernel_start} - ${prior_stage_dtb};" \
> > 
> > As Alexander Graf pointed out in reply to patch 24, we don't need
> > the
> > separate environment variable "prior_stage_dtb". I will replace it
> > with
> > "fdtcontroladdr" here and drop patch 24 in the next version.
> 
> Also, can you please enable distro boot? :)
> 
> 
> Thanks,
> 
> Alex

I haven't used distro boot yet, but I will take a look and see if I can
get it working. :)

Thanks,
Lukas


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