PCI: dwc: Add accessors for write permission of DBI read-only registers
The read-only DBI registers can be written only when the "Write to RO
Registers Using DBI" (DBI_RO_WR_EN) field of MISC_CONTROL_1_OFF is set.
Add accessors to enable and disable write permission, and use them instead
of accessing MISC_CONTROL_1_OFF directly.
Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Joao Pinto <jpinto@synopsys.com>
Acked-by: Roy Zang <tie-fei.zang@freescale.com>
diff --git a/drivers/pci/dwc/pcie-designware.h b/drivers/pci/dwc/pcie-designware.h
index 7366c81..0c5f874 100644
--- a/drivers/pci/dwc/pcie-designware.h
+++ b/drivers/pci/dwc/pcie-designware.h
@@ -76,6 +76,9 @@
#define PCIE_ATU_FUNC(x) (((x) & 0x7) << 16)
#define PCIE_ATU_UPPER_TARGET 0x91C
+#define PCIE_MISC_CONTROL_1_OFF 0x8BC
+#define PCIE_DBI_RO_WR_EN (0x1 << 0)
+
/*
* iATU Unroll-specific register definitions
* From 4.80 core version the address translation will be made by unroll
@@ -279,6 +282,28 @@ static inline u32 dw_pcie_readl_dbi2(struct dw_pcie *pci, u32 reg)
return __dw_pcie_read_dbi(pci, pci->dbi_base2, reg, 0x4);
}
+static inline void dw_pcie_dbi_ro_wr_en(struct dw_pcie *pci)
+{
+ u32 reg;
+ u32 val;
+
+ reg = PCIE_MISC_CONTROL_1_OFF;
+ val = dw_pcie_readl_dbi(pci, reg);
+ val |= PCIE_DBI_RO_WR_EN;
+ dw_pcie_writel_dbi(pci, reg, val);
+}
+
+static inline void dw_pcie_dbi_ro_wr_dis(struct dw_pcie *pci)
+{
+ u32 reg;
+ u32 val;
+
+ reg = PCIE_MISC_CONTROL_1_OFF;
+ val = dw_pcie_readl_dbi(pci, reg);
+ val &= ~PCIE_DBI_RO_WR_EN;
+ dw_pcie_writel_dbi(pci, reg, val);
+}
+
#ifdef CONFIG_PCIE_DW_HOST
irqreturn_t dw_handle_msi_irq(struct pcie_port *pp);
void dw_pcie_msi_init(struct pcie_port *pp);