From 33642e9e36dc084e4fc9245a266c9843bc8303b9 Mon Sep 17 00:00:00 2001 From: Niklas Cassel Date: Thu, 12 Mar 2026 14:02:33 +0100 Subject: PCI: endpoint: Introduce pci_epc_bar_type BAR_DISABLED Add a pci_epc_bar_type BAR_DISABLED to more clearly differentiate from BAR_RESERVED. This BAR type will only be used to describe a BAR that the EPC driver should disable, and will thus never be available to an EPF driver. (Unlike BAR_RESERVED, which will never be disabled by default by an EPC driver.) Co-developed-by: Manikanta Maddireddy Signed-off-by: Manikanta Maddireddy Signed-off-by: Niklas Cassel Signed-off-by: Manivannan Sadhasivam Tested-by: Koichiro Den Tested-by: Manikanta Maddireddy Reviewed-by: Frank Li Reviewed-by: Manikanta Maddireddy Link: https://patch.msgid.link/20260312130229.2282001-17-cassel@kernel.org --- include/linux/pci-epc.h | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index ebcdf70aa9b9..334c2b7578d0 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -191,13 +191,21 @@ struct pci_epc { * @BAR_RESIZABLE: The BAR implements the PCI-SIG Resizable BAR Capability. * NOTE: An EPC driver can currently only set a single supported * size. - * @BAR_RESERVED: The BAR should not be touched by an EPF driver. + * @BAR_RESERVED: Used for HW-backed BARs (e.g. MSI-X table, DMA regs). The BAR + * should not be disabled by an EPC driver. The BAR should not be + * reprogrammed by an EPF driver. An EPF driver is allowed to + * disable the BAR if absolutely necessary. (However, right now + * there is no EPC operation to disable a BAR that has not been + * programmed using pci_epc_set_bar().) + * @BAR_DISABLED: The BAR should be disabled by an EPC driver. The BAR will be + * unavailable to an EPF driver. */ enum pci_epc_bar_type { BAR_PROGRAMMABLE = 0, BAR_FIXED, BAR_RESIZABLE, BAR_RESERVED, + BAR_DISABLED, }; /** -- cgit v1.2.3