mbox series

[v2,0/2] of: populate of_root_node if not set (alternate)

Message ID 20230222221051.809091-1-frowand.list@gmail.com
Headers
Series of: populate of_root_node if not set (alternate) |

Message

Frank Rowand Feb. 22, 2023, 10:10 p.m. UTC 
  This series is a different implementation to achieve the goals of
https://lore.kernel.org/r/20220623105044.152832-1-clement.leger@bootlin.com

In order to apply overlays or create new nodes under the root node, the
kernel expects of_root to be set. On some system where a device-tree was
not provided by firmware (x86 for instance) if CONFIG_OF is enabled,
then we will end up with a null of_root. This series adds support to
create this root node using a builtin dtb and removes the manual
creation of the root node done in unittests.c.

Changes since version 1: (patch 1/2)
  - refresh for 6.2-rc1
  - update Signed-off-by
  - fix typo in of_fdt.h: s/of_setup/setup_of
  - unflatten_device_tree(): validate size in header field dtb_empty_root
    that will be used to copy dtb_empty_root
  - add Kconfig option to manually select CONFIG_OF_EARLY_FLATTREE

Changes since version 1: (patch 2/2)
  - refresh for 6.2-rc1
  - update Signed-off-by
  - fix formatting error (leading space) in patch comment

Frank Rowand (2):
  of: create of_root if no dtb provided
  of: unittest: treat missing of_root as error instead of fixing up

 drivers/of/Kconfig        |  7 ++++++-
 drivers/of/Makefile       |  2 +-
 drivers/of/empty_root.dts |  6 ++++++
 drivers/of/fdt.c          | 27 ++++++++++++++++++++++++++-
 drivers/of/unittest.c     | 16 ++++++----------
 include/linux/of_fdt.h    |  2 ++
 init/main.c               |  2 ++
 7 files changed, 49 insertions(+), 13 deletions(-)
 create mode 100644 drivers/of/empty_root.dts

Comments

Clément Léger Feb. 23, 2023, 10:41 a.m. UTC | #1 
Le Wed, 22 Feb 2023 16:10:49 -0600,
Frank Rowand <frowand.list@gmail.com> a écrit :

> This series is a different implementation to achieve the goals of
> https://lore.kernel.org/r/20220623105044.152832-1-clement.leger@bootlin.com
> 
> In order to apply overlays or create new nodes under the root node, the
> kernel expects of_root to be set. On some system where a device-tree was
> not provided by firmware (x86 for instance) if CONFIG_OF is enabled,
> then we will end up with a null of_root. This series adds support to
> create this root node using a builtin dtb and removes the manual
> creation of the root node done in unittests.c.

Hi Frank, I'm currently testing your series and I encountered some
crashes at boot. Looks like it comes from the
early_init_dt_alloc_memory_arch() that calls panic. Maybe the memblock
allocator is not ready yet. Please note that I'm testing it on a x86
kernel. I'll investigate that.

Regarding the series itself it seems ok to me.

Thanks,

Clément

> 
> Changes since version 1: (patch 1/2)
>   - refresh for 6.2-rc1
>   - update Signed-off-by
>   - fix typo in of_fdt.h: s/of_setup/setup_of
>   - unflatten_device_tree(): validate size in header field dtb_empty_root
>     that will be used to copy dtb_empty_root
>   - add Kconfig option to manually select CONFIG_OF_EARLY_FLATTREE
> 
> Changes since version 1: (patch 2/2)
>   - refresh for 6.2-rc1
>   - update Signed-off-by
>   - fix formatting error (leading space) in patch comment
> 
> Frank Rowand (2):
>   of: create of_root if no dtb provided
>   of: unittest: treat missing of_root as error instead of fixing up
> 
>  drivers/of/Kconfig        |  7 ++++++-
>  drivers/of/Makefile       |  2 +-
>  drivers/of/empty_root.dts |  6 ++++++
>  drivers/of/fdt.c          | 27 ++++++++++++++++++++++++++-
>  drivers/of/unittest.c     | 16 ++++++----------
>  include/linux/of_fdt.h    |  2 ++
>  init/main.c               |  2 ++
>  7 files changed, 49 insertions(+), 13 deletions(-)
>  create mode 100644 drivers/of/empty_root.dts
>