pci_ep: layerscape: Add the workaround for errata A-009460

The VF_BARn_REG register's Prefetchable and Type bit fields
are overwritten by a write to VF's BAR Mask register.
workaround: Before writing to the VF_BARn_MASK_REG register,
write 0b to the PCIE_MISC_CONTROL_1_OFF register.

Signed-off-by: Xiaowei Bao <xiaowei.bao@nxp.com>
Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>

diff --git a/drivers/pci/pcie_layerscape_ep.c b/drivers/pci/pcie_layerscape_ep.c
index e609607..3f22c5e 100644 (file)
--- a/drivers/pci/pcie_layerscape_ep.c
+++ b/drivers/pci/pcie_layerscape_ep.c
@@ -164,6 +164,15 @@ static void ls_pcie_setup_ep(struct ls_pcie_ep *pcie_ep)
        if (PCI_EXT_CAP_ID(sriov) == PCI_EXT_CAP_ID_SRIOV) {
                pcie_ep->sriov_flag = 1;
                for (pf = 0; pf < PCIE_PF_NUM; pf++) {
+                       /*
+                        * The VF_BARn_REG register's Prefetchable and Type bit
+                        * fields are overwritten by a write to VF's BAR Mask
+                        * register. Before writing to the VF_BARn_MASK_REG
+                        * register, write 0b to the PCIE_MISC_CONTROL_1_OFF
+                        * register.
+                        */
+                       writel(0, pcie->dbi + PCIE_MISC_CONTROL_1_OFF);
+
                        if (pcie_ep->cfg2_flag) {
                                for (vf = 0; vf <= PCIE_VF_NUM; vf++) {
                                        ctrl_writel(pcie,