PCI: layerscape: Fix MSG TLP drop setting

Some kinds of Layerscape PCIe controllers will forward the received message
TLPs to system application address space, which could corrupt system memory
or lead to a system hang.  Enable MSG_DROP to fix this issue.

Signed-off-by: Minghuan Lian <Minghuan.Lian@nxp.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 13 insertions, 8 deletions

diff --git a/drivers/pci/host/pci-layerscape.c b/drivers/pci/host/pci-layerscape.c
index 3923bed93c7e..f39961bcf7aa 100644
--- a/drivers/pci/host/pci-layerscape.c
+++ b/drivers/pci/host/pci-layerscape.c
@@ -77,6 +77,16 @@ static void ls_pcie_fix_class(struct ls_pcie *pcie)
         iowrite16(PCI_CLASS_BRIDGE_PCI, pcie->dbi + PCI_CLASS_DEVICE);
 }
 
+/* Drop MSG TLP except for Vendor MSG */
+static void ls_pcie_drop_msg_tlp(struct ls_pcie *pcie)
+{
+        u32 val;
+
+        val = ioread32(pcie->dbi + PCIE_STRFMR1);
+        val &= 0xDFFFFFFF;
+        iowrite32(val, pcie->dbi + PCIE_STRFMR1);
+}
+
 static int ls1021_pcie_link_up(struct pcie_port *pp)
 {
         u32 state;
@@ -97,7 +107,7 @@ static int ls1021_pcie_link_up(struct pcie_port *pp)
 static void ls1021_pcie_host_init(struct pcie_port *pp)
 {
         struct ls_pcie *pcie = to_ls_pcie(pp);
-        u32 val, index[2];
+        u32 index[2];
 
         pcie->scfg = syscon_regmap_lookup_by_phandle(pp->dev->of_node,
                                                      "fsl,pcie-scfg");
@@ -116,13 +126,7 @@ static void ls1021_pcie_host_init(struct pcie_port *pp)
 
         dw_pcie_setup_rc(pp);
 
-        /*
-         * LS1021A Workaround for internal TKT228622
-         * to fix the INTx hang issue
-         */
-        val = ioread32(pcie->dbi + PCIE_STRFMR1);
-        val &= 0xffff;
-        iowrite32(val, pcie->dbi + PCIE_STRFMR1);
+        ls_pcie_drop_msg_tlp(pcie);
 }
 
 static int ls_pcie_link_up(struct pcie_port *pp)
@@ -147,6 +151,7 @@ static void ls_pcie_host_init(struct pcie_port *pp)
         iowrite32(1, pcie->dbi + PCIE_DBI_RO_WR_EN);
         ls_pcie_fix_class(pcie);
         ls_pcie_clear_multifunction(pcie);
+        ls_pcie_drop_msg_tlp(pcie);
         iowrite32(0, pcie->dbi + PCIE_DBI_RO_WR_EN);
 }