PCI: dwc: ep: Correct PBA offset in .set_msix() callback

commit 810276362bad172d063d1f6be1cc2cb425b90103 upstream.

While dw_pcie_ep_set_msix() writes the Table Size field correctly (N-1),
the calculation of the PBA offset is wrong because it calculates space for
(N-1) entries instead of N.

This results in the following QEMU error when using PCI passthrough on a
device which relies on the PCI endpoint subsystem:

  failed to add PCI capability 0x11[0x50]@0xb0: table & pba overlap, or they don't fit in BARs, or don't align

Fix the calculation of PBA offset in the MSI-X capability.

[bhelgaas: more specific subject and commit log]

Fixes: 83153d9f36 ("PCI: endpoint: Fix ->set_msix() to take BIR and offset as arguments")
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20250514074313.283156-9-cassel@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Niklas Cassel
2025-05-14 09:43:14 +02:00
committed by Greg Kroah-Hartman
parent 523815857b
commit 68e58f5791

View File

@@ -398,6 +398,7 @@ static int dw_pcie_ep_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
struct dw_pcie_ep_func *ep_func;
u32 val, reg;
u16 actual_interrupts = interrupts + 1;
ep_func = dw_pcie_ep_get_func_from_ep(ep, func_no);
if (!ep_func || !ep_func->msix_cap)
@@ -408,7 +409,7 @@ static int dw_pcie_ep_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
reg = ep_func->msix_cap + PCI_MSIX_FLAGS;
val = dw_pcie_ep_readw_dbi(ep, func_no, reg);
val &= ~PCI_MSIX_FLAGS_QSIZE;
val |= interrupts;
val |= interrupts; /* 0's based value */
dw_pcie_writew_dbi(pci, reg, val);
reg = ep_func->msix_cap + PCI_MSIX_TABLE;
@@ -416,7 +417,7 @@ static int dw_pcie_ep_set_msix(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
dw_pcie_ep_writel_dbi(ep, func_no, reg, val);
reg = ep_func->msix_cap + PCI_MSIX_PBA;
val = (offset + (interrupts * PCI_MSIX_ENTRY_SIZE)) | bir;
val = (offset + (actual_interrupts * PCI_MSIX_ENTRY_SIZE)) | bir;
dw_pcie_ep_writel_dbi(ep, func_no, reg, val);
dw_pcie_dbi_ro_wr_dis(pci);