Re: [PATCH v3 00/15] Bring suspend to RAM support to PCIe Aardvark driver

[Lorenzo Pieralisi]

On Tue, Jan 08, 2019 at 05:24:25PM +0100, Miquel Raynal wrote:
> Hello,
> 
> As part of an effort to bring suspend to RAM support to Armada 3700
> SoCs (main target: ESPRESSObin), this series handles the work around
> the PCIe IP.
> 
> First, more configuration is done in the 'setup' helper as inspired
> from the U-Boot driver. This is needed to entirely initialize the IP
> during future resume operation (patch 1).
> 
> Then, reset GPIO, PHY and clock support are introduced (patch 2-4). As
> current device trees do not provide the corresponding properties, not
> finding one of these properties is not an error and just produces a
> warning. However, if the property is present, an error during PHY
> initialization will fail the probe of the driver.
> 
> Note: To be sure the clock will be resumed before this driver, a first
> series adding links between clocks and consumers has been submitted,
> see [1]. Anyway, having the clock series applied first is not needed.

I do not understand what this means, in particular in relation
to the blocking clock calls in the suspend/resume NOIRQ hooks.

Thanks,
Lorenzo

> Patch 5 adds suspend/resume hooks, re-using all the above.
> 
> Finally, bindings and device trees are updated to reflect the hardware
> (patch 6-12). While the clock depends on the SoC, the reset GPIO and
> the PHY depends on the board so the clock is added in the
> armada-37xx.dtsi file while the two other properties are added in
> armada-3720-espressobin.dts.
> 
> [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2019-January/623885.html
> 
> Thanks,
> Miqu??l
> 
> 
> Changes since v2:
> =================
> * Minor patches reordering.
> * Added pinctrl patches from Gregory Clement fixing the PCIe pins. His
>   changes implied modifications in the DT/bindings patches adding PCIe
>   reset pin support.
> * Added a new patch that enlarges the PIO timeout of the driver
>   (explanations in the commit log).
> * With the timeout changed, removed the "experimental delay" that was
>   needed at resume time before accessing any register.
> 
> Changes since v1:
> =================
> * Change the capitalization in commit titles to follow the PCI
>   subsystem rules.
> * Added Suggested-by tag to the patch adding PHY support and to the
>   patch adding the PHY property in the DT.
> * Added Rob's Reviewed-by tags on bindings.
> * I am following the discussion about calling functions that might
>   sleep in a NOIRQ context. As there is no real problem yet (as per my
>   understanding), I did not change anything on this regard.
> 
> 
> Miquel Raynal (15):
>   PCI: aardvark: Enlarge PIO timeout
>   PCI: aardvark: Configure more registers in the configuration helper
>   PCI: aardvark: Add clock support
>   PCI: aardvark: Add PHY support
>   PCI: aardvark: Add PCIe warm reset support
>   PCI: aardvark: Add external reset GPIO support
>   PCI: aardvark: Add suspend to RAM support
>   dt-bindings: PCI: aardvark: Describe the clocks property
>   dt-bindings: PCI: aardvark: Describe the PHY property
>   dt-bindings: PCI: aardvark: Describe the PCIe endpoint card reset pins
>   dt-bindings: PCI: aardvark: Describe the reset-gpios property
>   ARM64: dts: marvell: armada-37xx: declare PCIe clock
>   ARM64: dts: marvell: armada-3720-espressobin: declare PCIe PHY
>   ARM64: dts: marvell: armada-37xx: declare PCIe reset pin
>   ARM64: dts: marvell: armada-3720-espressobin: declare PCIe warm reset
>     pin
> 
>  .../devicetree/bindings/pci/aardvark-pci.txt  |  14 ++
>  .../dts/marvell/armada-3720-espressobin.dts   |   3 +
>  arch/arm64/boot/dts/marvell/armada-37xx.dtsi  |  10 +
>  drivers/pci/controller/pci-aardvark.c         | 217 +++++++++++++++++-
>  4 files changed, 243 insertions(+), 1 deletion(-)
> 
> -- 
> 2.19.1
>