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: endpoint: Refactor pci_epf_alloc_space() API

Refactor pci_epf_alloc_space() API to accept "epc_features" as a parameter.
This is a preparatory work to make the API more robust.

Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Link: https://lore.kernel.org/r/20240207213922.1796533-2-cassel@kernel.org
[mani: reworded commit message]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

PCI: endpoint: pci-epf-ntb: Make struct pci_epf_ops const

The pci_epf_ops struct for the PCI endpoint NTB driver is never modified.

Mark it as const so it can be placed in the read-only section.

[kwilczynski: commit log]
Link: https://lore.kernel.org/linux-pci/20230722230848.589428-3-lars@metafoo.de
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>

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: endpoint: Pass EPF device ID to the probe function

Currently, the EPF probe function doesn't get the device ID argument needed
to correctly identify the device table ID of the EPF device.

When multiple entries are added to the "struct pci_epf_device_id" table,
the probe function needs to identify the correct one. This is achieved by
modifying the pci_epf_match_id() function to return the match ID pointer
and passing it to the driver's probe function.

pci_epf_device_match() function can return bool based on the return value
of pci_epf_match_id().

Link: https://lore.kernel.org/r/20230602114756.36586-3-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kishon Vijay Abraham I <kishon@kernel.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>

PCI: Correct misspelled words

Fix a number of misspelled words, and while at it, correct two phrases used
to indicate a status of an operation where words used have been cleverly
truncated and thus always trigger a spellchecking error while performing a
static code analysis over the PCI tree.

[bhelgaas: reverse sense of quirk ternary]
Link: https://lore.kernel.org/r/20220107225942.121484-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: endpoint: Use sysfs_emit() in "show" functions

Convert sprintf() in sysfs "show" functions to sysfs_emit() in order to
check for buffer overruns in sysfs outputs.

Link: https://lore.kernel.org/r/1630472957-26857-1-git-send-email-hayashi.kunihiko@socionext.com
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Krzysztof Wilczyński <kw@linux.com>

PCI/sysfs: Return -EINVAL consistently from "store" functions

Most of the "store" functions that handle userspace input via sysfs return
-EINVAL should the value fail validation and/or type conversion. This
error code is a clear message to userspace that the value is not a valid
input.

However, some of the "show" functions return input parsing error codes
as-is, which may be either -EINVAL or -ERANGE. The former would often be
from kstrtobool(), and the latter typically from other kstr*() functions
such as kstrtou8(), kstrtou32(), kstrtoint(), etc.

-EINVAL is commonly returned as the error code to indicate that the value
provided is invalid, but -ERANGE is not very useful in userspace.

Therefore, normalize the return error code to be -EINVAL for when the
validation and/or type conversion fails.

Link: https://lore.kernel.org/r/20210915230127.2495723-2-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: endpoint: Add virtual function number in pci_epc ops

Add virtual function number in pci_epc ops. EPC controller driver
can perform virtual function specific initialization based on the
virtual function number.

Link: https://lore.kernel.org/r/20210819123343.1951-5-kishon@ti.com
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

PCI: Fix kernel-doc errors

Fix kernel-doc formatting errors, function names that don't match the doc,
and some missing parameter documentation. These are reported by:

make W=1 drivers/pci/

No functional change intended.

[bhelgaas: squashed into one patch since this only changes comments]
Link: https://lore.kernel.org/r/20210311001724.423356-1-kw@linux.com
Link: https://lore.kernel.org/r/20210311001724.423356-2-kw@linux.com
Link: https://lore.kernel.org/r/20210311001724.423356-3-kw@linux.com
Link: https://lore.kernel.org/r/20210311001724.423356-4-kw@linux.com
Link: https://lore.kernel.org/r/20210311001724.423356-5-kw@linux.com
Link: https://lore.kernel.org/r/20210311001724.423356-6-kw@linux.com
Link: https://lore.kernel.org/r/20210311001724.423356-7-kw@linux.com
Link: https://lore.kernel.org/r/20210311001724.423356-8-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: endpoint: Add EP function driver to provide NTB functionality

Add a new endpoint function driver to provide NTB functionality using
multiple PCIe endpoint instances.

[arnd@arndb.de: Select configfs dependency]
[yebin10@huawei.com: Fix unused but set variables]
[geert+renesas@glider.be: Explain NTB in PCI_EPF_NTB help text]

Link: https://lore.kernel.org/r/20210201195809.7342-14-kishon@ti.com
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ye Bin <yebin10@huawei.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>