PCI: endpoint: Clean up hardware description for BARs

The hardware description for BARs is scattered in many different variables
in pci_epc_features. Some of these things are mutually exclusive, so it
can create confusion over which variable that has precedence over another.

Improve the situation by creating a struct pci_epc_bar_desc, and a new
enum pci_epc_bar_type, and convert the endpoint controller drivers to use
this more well defined format.

Additionally, some endpoint controller drivers mark the BAR succeeding a
"64-bit only BAR" as reserved, while some do not. By definition, a 64-bit
BAR uses the succeeding BAR for the upper 32-bits, so an EPF driver cannot
use a BAR succeeding a 64-bit BAR. Ensure that all endpoint controller
drivers are uniform, and actually describe a reserved BAR as reserved.

Signed-off-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Kishon Vijay Abraham I <kishon@kernel.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20240216134524.1142149-2-cassel@kernel.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

PCI: dwc: Rename .ep_init to .init in struct dw_pcie_ep_ops

Since the name of the dw_pcie_ep_ops struct makes it obvious that it's
for the PCIe Endpoint, rename the struct member .ep_init to .init.

[kwilczynski: commit log]
Suggested-by: Serge Semin <fancer.lancer@gmail.com>
Suggested-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/linux-pci/20231220053829.1921187-3-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Reviewed-by: Srikanth Thokala <srikanth.thokala@intel.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>

PCI: endpoint: Drop PCI_EPC_IRQ_XXX definitions

linux/pci.h defines the IRQ flags PCI_IRQ_INTX, PCI_IRQ_MSI and
PCI_IRQ_MSIX. Let's use these flags directly instead of the endpoint
definitions provided by enum pci_epc_irq_type. This removes the need
for defining this enum type completely.

Link: https://lore.kernel.org/r/20231122060406.14695-3-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

PCI: keembay: Remove cast between incompatible function type

Rather than casting void(*)(struct clk *) to void (*)(void *), that
forces conversion to an incompatible function type, replace the cast
with a small local stub function with a signature that matches what
the devm_add_action_or_reset() function expects.

The sub function takes a void *, then passes it directly to
clk_disable_unprepare(), which handles the more specific type.

Reported by clang when building with warnings enabled:

drivers/pci/controller/dwc/pcie-keembay.c:172:12: warning: cast from 'void (*)(struct clk *)' to 'void (*)(void *)' converts to incompatible function type [-Wcast-function-type-strict]
(void(*)(void *))clk_disable_unprepare,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
No functional changes are intended.

Fixes: 0c87f90b4c13 ("PCI: keembay: Add support for Intel Keem Bay")
Link: https://lore.kernel.org/linux-pci/20230629165956.237832-2-kwilczynski@kernel.org
Acked-by: Srikanth Thokala <srikanth.thokala@intel.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>

PCI: dwc: Convert struct pcie_port.msi_irq to an array

The Qualcomm DWC PCIe controller supports more than 32 MSI interrupts, but
they are routed to separate interrupts in groups of 32 vectors. To support
this configuration, change the msi_irq field to an array. Let the DWC core
handle all interrupts that were set in this array.

[bhelgaas: reorder, drop "irq" temporary to make patch cleaner]
Link: https://lore.kernel.org/r/20220707134733.2436629-3-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

PCI: dwc: Rename struct pcie_port to dw_pcie_rp

All of the DW PCIe core driver entities except the pcie_port struct have
names with the "dw_" prefix to distinguish local and common PCIe name
spaces, and endpoint-related entities have an "_ep" suffix.

Rename struct pcie_port to dw_pcie_rp to make it more consistent with other
names.

[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20220624143428.8334-16-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>

PCI: keembay: Add support for Intel Keem Bay

Add driver for Intel Keem Bay SoC PCIe controller. This controller
is based on DesignWare PCIe core.

In Root Complex mode, only internal reference clock is possible for
Keem Bay A0. For Keem Bay B0, external reference clock can be used
and will be the default configuration. Currently, keembay_pcie_of_data
structure has one member. It will be expanded later to handle this
difference.

Endpoint mode link initialization is handled by the boot firmware.

Link: https://lore.kernel.org/r/20210805211010.29484-3-srikanth.thokala@intel.com
Signed-off-by: Wan Ahmad Zainie <wan.ahmad.zainie.wan.mohamad@intel.com>
Signed-off-by: Srikanth Thokala <srikanth.thokala@intel.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Krzysztof Wilczyński <kw@linux.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>