[PATCH 4/6] PCI: mobiveil: Add workaround for unsupported request error

From: Xiaowei Bao
Date: Mon Feb 18 2019 - 04:53:14 EST


Errata: unsupported request error on inbound posted write
transaction, PCIe controller reports advisory error instead
of uncorrectable error message to RC.

Signed-off-by: Xiaowei Bao <xiaowei.bao@xxxxxxx>
---
depends on: http://patchwork.ozlabs.org/project/linux-pci/list/?series=88754

.../controller/mobiveil/pci-layerscape-gen4-ep.c | 14 +++++++++++++-
drivers/pci/controller/mobiveil/pcie-mobiveil.h | 4 ++++
2 files changed, 17 insertions(+), 1 deletions(-)

diff --git a/drivers/pci/controller/mobiveil/pci-layerscape-gen4-ep.c b/drivers/pci/controller/mobiveil/pci-layerscape-gen4-ep.c
index dc3589d..3d980f5 100644
--- a/drivers/pci/controller/mobiveil/pci-layerscape-gen4-ep.c
+++ b/drivers/pci/controller/mobiveil/pci-layerscape-gen4-ep.c
@@ -51,7 +51,19 @@ static void ls_pcie_g4_ep_init(struct mobiveil_pcie_ep *ep)
struct mobiveil_pcie *mv_pci = to_mobiveil_pcie_from_ep(ep);
struct pci_epc *epc = ep->epc;
enum pci_barno bar;
- int win_idx;
+ int win_idx, val;
+
+ /*
+ * Errata: unsupported request error on inbound posted write
+ * transaction, PCIe controller reports advisory error instead
+ * of uncorrectable error message to RC.
+ * workaround: set the bit20(unsupported_request_Error_severity) with
+ * value 1 in uncorrectable_Error_Severity_Register, make the
+ * unsupported request error generate the fatal error.
+ */
+ val = csr_readl(mv_pci, CFG_UNCORRECTABLE_ERROR_SEVERITY);
+ val |= 1 << UNSUPPORTED_REQUEST_ERROR_SHIFT;
+ csr_writel(mv_pci, val, CFG_UNCORRECTABLE_ERROR_SEVERITY);

ls_pcie_g4_get_bar_num(ep);

diff --git a/drivers/pci/controller/mobiveil/pcie-mobiveil.h b/drivers/pci/controller/mobiveil/pcie-mobiveil.h
index 275c68f..7dc2a12 100644
--- a/drivers/pci/controller/mobiveil/pcie-mobiveil.h
+++ b/drivers/pci/controller/mobiveil/pcie-mobiveil.h
@@ -120,6 +120,10 @@
#define GPEX_BAR_SIZE_UDW 0x4DC
#define GPEX_BAR_SELECT 0x4E0

+#define CFG_UNCORRECTABLE_ERROR_SEVERITY 0x10c
+#define UNSUPPORTED_REQUEST_ERROR_SHIFT 20
+#define CFG_UNCORRECTABLE_ERROR_MASK 0x108
+
/* starting offset of INTX bits in status register */
#define PAB_INTX_START 5

--
1.7.1