This driver is DT based and utilizes the DesignWare APIs.
It allows using a smaller ECAM range for a larger bus range -
usually an entire bus uses 1MB of address space, but the driver
can use it for a larger number of buses. This is achieved by using a HW
mechanism which allows changing the BUS part of the "final" outgoing
config transaction. There are 2 HW regs, one which is basically a
bitmask determining which bits to take from the AXI transaction itself
and another which holds the complementary part programmed by the
driver.
All link initializations are handled by the boot FW.
Signed-off-by: Jonathan Chocron <jonnyc@amazon.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Reviewed-by: Andrew Murray <andrew.murray@arm.com>
Add driver for Amazon's Annapurna Labs PCIe host controller. The
controller is based on DesignWare's IP.
The controller doesn't support accessing the Root Port's config space via
ECAM, so we obtain its base address via an AMZN0001 device.
Furthermore, the DesignWare PCIe controller doesn't filter out config
transactions sent to devices 1 and up on its bus, so they are filtered by
the driver.
All subordinate buses do support ECAM access.
Implementing specific PCI config access functions involves:
- Adding an init function to obtain the Root Port's base address from
an AMZN0001 device.
- Adding a new entry in the MCFG quirk array.
[bhelgaas: Note that there is no Kconfig option for this driver because it
is only intended for use with the generic ACPI host bridge driver. This
driver is only needed because the DesignWare IP doesn't completely support
ECAM access to the root bus.]
Link: https://lore.kernel.org/lkml/1553774276-24675-1-git-send-email-jonnyc@amazon.com
Co-developed-by: Vladimir Aerov <vaerov@amazon.com>
Signed-off-by: Jonathan Chocron <jonnyc@amazon.com>
Signed-off-by: Vladimir Aerov <vaerov@amazon.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Jonathan Chocron