From 74ec00a9f336152fccf8df9cc9c5a46ab1a649b4 Mon Sep 17 00:00:00 2001 From: Michael Brown Date: Thu, 2 Nov 2023 15:05:15 +0000 Subject: [pci] Handle non-zero starting bus in ECAM allocations The base address provided in the PCI ECAM allocation within the ACPI MCFG table is the base address for the segment as a whole, not for the starting bus within that allocation. On machines that provide ECAM allocations with a non-zero starting bus number (observed with an AWS EC2 m7a.large instance), this will result in iPXE accessing the wrong memory addresses within the ECAM region. Fix by adding the appropriate starting bus offset to the base address. Signed-off-by: Michael Brown --- src/drivers/bus/ecam.c | 1 + 1 file changed, 1 insertion(+) diff --git a/src/drivers/bus/ecam.c b/src/drivers/bus/ecam.c index 376f349..dd3e1e5 100644 --- a/src/drivers/bus/ecam.c +++ b/src/drivers/bus/ecam.c @@ -150,6 +150,7 @@ static int ecam_access ( struct pci_device *pci ) { /* Map configuration space for this allocation */ base = le64_to_cpu ( ecam.alloc.base ); + base += ( ecam.alloc.start * ECAM_SIZE * PCI_BUSDEVFN ( 0, 1, 0, 0 ) ); len = ( ecam.range.count * ECAM_SIZE ); ecam.regs = ioremap ( base, len ); if ( ! ecam.regs ) { -- cgit v1.1