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

[Xiaowei Bao]

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>
---
 drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c | 13 +++++++++++++
 drivers/pci/controller/mobiveil/pcie-mobiveil.h           |  4 ++++
 2 files changed, 17 insertions(+)

diff --git a/drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c b/drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c
index 7bfec51..5bc9ed7 100644
--- a/drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c
+++ b/drivers/pci/controller/mobiveil/pcie-layerscape-gen4-ep.c
@@ -49,6 +49,19 @@ static void ls_pcie_g4_ep_init(struct mobiveil_pcie_ep *ep)
 	struct mobiveil_pcie *mv_pci = to_mobiveil_pcie_from_ep(ep);
 	int win_idx;
 	u8 bar;
+	u32 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);
 
 	ep->bar_num = PCIE_LX2_BAR_NUM;
 
diff --git a/drivers/pci/controller/mobiveil/pcie-mobiveil.h b/drivers/pci/controller/mobiveil/pcie-mobiveil.h
index 7308fa4..a40707e 100644
--- a/drivers/pci/controller/mobiveil/pcie-mobiveil.h
+++ b/drivers/pci/controller/mobiveil/pcie-mobiveil.h
@@ -123,6 +123,10 @@
 #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
 
-- 
2.9.5