[PATCH 0/2] Translate of PCI address without PCI enabled
Ezequiel Garcia
ezequiel.garcia at free-electrons.com
Wed Feb 19 19:50:28 EST 2014
On Wed, Feb 19, 2014 at 11:14:54PM +0100, Gregory CLEMENT wrote:
> Hello,
>
> This patch set makes the use of the of PCI address translator less
> restrictive. At the end it will allow to use the mvebu_get_soc_id
> unconditionally.
>
> The mvebu SoC (such as Kirkwood, Dove or Armada XP for instance) come
> with an IP of a PCI controller. The ID and the revision of a SoC are
> stored in the registers of this controller. Being able to get this
> information allows to deals with errata more dynamically.
>
> To manage to read this information, we need to map the registers, and
> for this we need to use the of PCI translator which depend of the PCI
> support.
>
> However there are mvebu board without any PCI devices, and where
> selecting the PCI support would be useless.
>
> Moreover translating an address from a PCI node of the device-tree
> into a CPU physical address doesn't require the core PCI
> support. Those translations are just related to the device tree
> itself.
>
> The 1st patch introduces a new config symbol: OF_ADDRESS_PCI, which
> will be selected as soon as PCI will be selected, so we remains in the
> same situation the current code. It should go to the of tree.
>
> The 2nd patch selects OF_ADDRESS_PCI as soon as ARCH_MVEBU will be
> selected. This will make mvebu_get_soc_id available even without the
> PCI support. It should go to the mvebu tree.
>
> Thanks,
>
> Gregory CLEMENT (2):
> of: Allows to use the PCI translator without the PCI core
> ARM: mvebu: Allows to get the SoC ID even without PCI enabled
>
> arch/arm/mach-mvebu/Kconfig | 1 +
> drivers/of/Kconfig | 4 ++++
> drivers/of/address.c | 8 +++++---
> 3 files changed, 10 insertions(+), 3 deletions(-)
>
> --
> 1.8.1.2
>
On XP GP and CONFIG_PCI=n, without the patches I get this:
mvebu-soc-id: cannot map registers
and after applying the patches I have:
mvebu-soc-id: MVEBU SoC ID=0x7846, Rev=0x2
Tested-by: Ezequiel Garcia <ezequiel.garcia at free-electrons.com>
Reviewed-by: Ezequiel Garcia <ezequiel.garcia at free-electrons.com>
Thanks for taking care of this.
--
Ezequiel García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com
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