PCI: Restore resized BAR state on resume
Resize BARs after resume to the expected size again.
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199959
Fixes: d6895ad39f3b ("drm/amdgpu: resize VRAM BAR for CPU access v6")
Fixes: 276b738deb5b ("PCI: Add resizable BAR infrastructure")
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org # v4.15+
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 97acba7..44ccfb3 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1171,6 +1171,33 @@ static void pci_restore_config_space(struct pci_dev *pdev)
}
}
+static void pci_restore_rebar_state(struct pci_dev *pdev)
+{
+ unsigned int pos, nbars, i;
+ u32 ctrl;
+
+ pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_REBAR);
+ if (!pos)
+ return;
+
+ pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
+ nbars = (ctrl & PCI_REBAR_CTRL_NBAR_MASK) >>
+ PCI_REBAR_CTRL_NBAR_SHIFT;
+
+ for (i = 0; i < nbars; i++, pos += 8) {
+ struct resource *res;
+ int bar_idx, size;
+
+ pci_read_config_dword(pdev, pos + PCI_REBAR_CTRL, &ctrl);
+ bar_idx = ctrl & PCI_REBAR_CTRL_BAR_IDX;
+ res = pdev->resource + bar_idx;
+ size = order_base_2((resource_size(res) >> 20) | 1) - 1;
+ ctrl &= ~PCI_REBAR_CTRL_BAR_SIZE;
+ ctrl |= size << 8;
+ pci_write_config_dword(pdev, pos + PCI_REBAR_CTRL, ctrl);
+ }
+}
+
/**
* pci_restore_state - Restore the saved state of a PCI device
* @dev: - PCI device that we're dealing with
@@ -1186,6 +1213,7 @@ void pci_restore_state(struct pci_dev *dev)
pci_restore_pri_state(dev);
pci_restore_ats_state(dev);
pci_restore_vc_state(dev);
+ pci_restore_rebar_state(dev);
pci_cleanup_aer_error_status_regs(dev);