[U-Boot] [PATCH 1/4] Implement "pci enum" command for CONFIG_DM_PCI

Bin Meng bmeng.cn at gmail.com
Wed Jan 27 07:17:12 CET 2016


On Wed, Jan 27, 2016 at 2:10 AM, Stephen Warren <swarren at wwwdotorg.org> wrote:
> From: Stephen Warren <swarren at nvidia.com>
>
> With CONFIG_DM_PCI enabled, PCI buses are not enumerated at boot, as they
> are without that config option enabled. No command exists to enumerate the
> PCI buses. Hence, unless some board-specific code causes PCI enumeration,
> PCI-based Ethernet devices are not detected, and network access is not
> available.
>
> This patch implements "pci enum" in the CONFIG_DM_PCI case, thus giving a
> mechanism whereby PCI can be enumerated.
>
> do_pci()'s handling of case 'e' is moved into a single location before the
> dev variable is assigned, in order to skip calculation of dev. The enum
> sub-command doesn't need the dev value, and skipping its calculation
> avoids an irrelevant error being printed.
>
> Using a command to initialize PCI like this has a disadvantage relative to
> enumerating PCI at boot. In particular, Ethernet devices are not probed
> during PCI enumeration, but only when used. This defers setting variables
> such as ethact, ethaddr, etc. until the first network-related command is
> executed. Hopefully this will not cause further issues. Perhaps in the
> long term, we need a "net start/enum" command too?
>
> Signed-off-by: Stephen Warren <swarren at nvidia.com>
> ---
> This series naturally needs to be applied in order in a single branch.
> This series depends on all previous applied test/py patches.
>
>  common/cmd_pci.c         | 18 +++++-------------
>  drivers/pci/pci-uclass.c | 15 +++++++++++++++
>  2 files changed, 20 insertions(+), 13 deletions(-)
>

Reviewed-by: Bin Meng <bmeng.cn at gmail.com>


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