By default, the Marvell hardware, for each PCIe interface, exhibits
the following devices:
* On slot 0, a "Marvell Memory controller", identical on all PCIe
interfaces, and which isn't useful when the Marvell SoC is the PCIe
root complex (i.e, the normal case when we run Linux on the Marvell
SoC).
* On slot 1, the real PCIe card connected into the PCIe slot of the
board.
So, what the Marvell PCIe driver was doing in its PCI-to-PCI bridge
emulation is that when the Linux PCI core was trying to access the
device in slot 0, we were in fact forwarding the configuration
transaction to the device in slot 1. For all other slots, we were
telling the Linux PCI core that there was no device connected.
However, new versions of bootloaders from Marvell change the default
PCIe configuration, and make the real device appear in slot 0, and the
"Marvell Memory controller" in slot 1.
Therefore, this commit modifies the Marvell PCIe driver to adjust the
PCIe hardware configuration to make sure that this behavior (real
device in slot 0, "Marvell Memory controller" in slot 1) is the one
we'll see regardless of what the bootloader has done. It allows to
remove the little hack that was forwarding configuration transactions
on slot 0 to slot 1, which is nice.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
In case of error, function of_clk_get_by_name() returns
ERR_PTR() never returns NULL. The NULL test in the return
value check should be replaced with IS_ERR().
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
This driver implements the support for the PCIe interfaces on the
Marvell Armada 370/XP ARM SoCs. In the future, it might be extended to
cover earlier families of Marvell SoCs, such as Dove, Orion and
Kirkwood.
The driver implements the hw_pci operations needed by the core ARM PCI
code to setup PCI devices and get their corresponding IRQs, and the
pci_ops operations that are used by the PCI core to read/write the
configuration space of PCI devices.
Since the PCIe interfaces of Marvell SoCs are completely separate and
not linked together in a bus, this driver sets up an emulated PCI host
bridge, with one PCI-to-PCI bridge as child for each hardware PCIe
interface.
In addition, this driver enumerates the different PCIe slots, and for
those having a device plugged in, it sets up the necessary address
decoding windows, using the mvebu-mbus driver.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Thomas Petazzoni