From d91dfe5054d4f2c424bd70ca34fc3328ee179f20 Mon Sep 17 00:00:00 2001 From: Hou Zhiqiang Date: Mon, 28 Aug 2017 18:53:00 +0800 Subject: [PATCH] PCI: dwc: Enable write permission for Class Code, Interrupt Pin updates dw_pcie_setup_rc() contains fixes to update the Class Code and Interrupt Pin registers, but the fixes don't actually work because these registers are read-only. Enable write permission before updating the Class Code and Interrupt Pin. Signed-off-by: Hou Zhiqiang Signed-off-by: Bjorn Helgaas Acked-by: Joao Pinto Acked-by: Roy Zang --- drivers/pci/dwc/pcie-designware-host.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/pci/dwc/pcie-designware-host.c b/drivers/pci/dwc/pcie-designware-host.c index 99cb70b5de79..0985aeee917c 100644 --- a/drivers/pci/dwc/pcie-designware-host.c +++ b/drivers/pci/dwc/pcie-designware-host.c @@ -597,10 +597,12 @@ void dw_pcie_setup_rc(struct pcie_port *pp) dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_1, 0x00000000); /* setup interrupt pins */ + dw_pcie_dbi_ro_wr_en(pci); val = dw_pcie_readl_dbi(pci, PCI_INTERRUPT_LINE); val &= 0xffff00ff; val |= 0x00000100; dw_pcie_writel_dbi(pci, PCI_INTERRUPT_LINE, val); + dw_pcie_dbi_ro_wr_dis(pci); /* setup bus numbers */ val = dw_pcie_readl_dbi(pci, PCI_PRIMARY_BUS); @@ -637,8 +639,12 @@ void dw_pcie_setup_rc(struct pcie_port *pp) dw_pcie_wr_own_conf(pp, PCI_BASE_ADDRESS_0, 4, 0); + /* Enable write permission for the DBI read-only register */ + dw_pcie_dbi_ro_wr_en(pci); /* program correct class for RC */ dw_pcie_wr_own_conf(pp, PCI_CLASS_DEVICE, 2, PCI_CLASS_BRIDGE_PCI); + /* Better disable write permission right after the update */ + dw_pcie_dbi_ro_wr_dis(pci); dw_pcie_rd_own_conf(pp, PCIE_LINK_WIDTH_SPEED_CONTROL, 4, &val); val |= PORT_LOGIC_SPEED_CHANGE; -- 2.20.1