On Wed, Mar 30, 2022 at 12:59 AM Andrew Scull <asc...@google.com> wrote:
>
> Add a config to control whether Enhanced Allocation is supported by the
> driver.
>
> Signed-off-by: Andrew Scull <asc...@google.com>
> ---
> drivers/pci/Kconfig | 7 +++++++
> drivers/pci/pci-uclass.c | 25 +++++++++++++++----------
> 2 files changed, 22 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
> index 47cd074aa1..fd2203420c 100644
> --- a/drivers/pci/Kconfig
> +++ b/drivers/pci/Kconfig
> @@ -67,6 +67,13 @@ config PCI_SRIOV
> if available on a PCI Physical Function device and probe for
> applicable drivers.
>
> +config PCI_ENHANCED_ALLOCATION
> + bool "Enable support for Enhanced Allocation of resources"
> + default y
> + help
> + Enable support for Enhanced Allocation which can be used by
> supported
> + devices in place of traditional BARS for allocation of resources.
> +
Why do we need a config option for EA as it can be figured out in the run time?
> config PCI_ARID
> bool "Enable Alternate Routing-ID support for PCI"
> help
> diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c
> index 8bbeb62f2e..719656eb3a 100644
> --- a/drivers/pci/pci-uclass.c
> +++ b/drivers/pci/pci-uclass.c
> @@ -645,7 +645,11 @@ int dm_pci_hose_probe_bus(struct udevice *bus)
> return log_msg_ret("probe", -EINVAL);
> }
>
> - ea_pos = dm_pci_find_capability(bus, PCI_CAP_ID_EA);
> + if (IS_ENABLED(CONFIG_PCI_ENHANCED_ALLOCATION))
> + ea_pos = dm_pci_find_capability(bus, PCI_CAP_ID_EA);
> + else
> + ea_pos = 0;
> +
> if (ea_pos) {
> dm_pci_read_config8(bus, ea_pos + sizeof(u32) + sizeof(u8),
> ®);
> @@ -1600,15 +1604,16 @@ void *dm_pci_map_bar(struct udevice *dev, int bar,
> unsigned long flags)
> udev = pdata->pfdev;
> }
>
> - /*
> - * if the function supports Enhanced Allocation use that instead of
> - * BARs
> - * Incase of virtual functions, pdata will help read VF BEI
> - * and EA entry size.
> - */
> - ea_off = dm_pci_find_capability(udev, PCI_CAP_ID_EA);
> - if (ea_off)
> - return dm_pci_map_ea_bar(udev, bar, ea_off, pdata);
> + if (IS_ENABLED(CONFIG_PCI_ENHANCED_ALLOCATION)) {
> + /*
> + * If the function supports Enhanced Allocation use that
> + * instead of BARs. Incase of virtual functions, pdata will
> + * help read VF BEI and EA entry size.
> + */
> + ea_off = dm_pci_find_capability(udev, PCI_CAP_ID_EA);
> + if (ea_off)
> + return dm_pci_map_ea_bar(udev, bar, ea_off, pdata);
> + }
>
> /* read BAR address */
> dm_pci_read_config32(udev, bar, &bar_response);
> --
Regards,
Bin
