Re: [U-Boot] [PATCH v4 02/11] x86: quark: Avoid chicken and egg problem

On 3 September 2015 at 06:37, Bin Meng bmeng.cn@gmail.com wrote:

If we convert to use driver model pci on quark, we will encounter some chicken and egg problems like below:

• To enable PCIe root ports, we need program some registers on the message bus via pci bus. With driver model, the first time to access pci bus, the pci enumeration process will be triggered. But without first enabling PCIe root ports, pci enumeration just hangs when scanning PCIe root ports.
• Similar situation happens when trying to access GPIO from the PCIe enabling codes, as GPIO requires its block base address to be assigned via a pci configuration register in the bridge.

To avoid such dilemma, replace all pci calls in the quark codes to use the local version which does not go through driver model.

Signed-off-by: Bin Meng bmeng.cn@gmail.com Acked-by: Simon Glass sjg@chromium.org

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Changes in v4: None Changes in v3: None Changes in v2:

• New patch to avoid chicken and egg problem

arch/x86/cpu/quark/quark.c | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-)

Applied to u-boot-x86, thanks!