[PATCH V2 04/16] PCI: dwc: Perform dbi regs write lock towards the end

From: Vidya Sagar
Date: Thu Apr 04 2019 - 15:55:30 EST


Remove multiple write enable and disable sequences of dbi registers as
Tegra194 implements writes to BAR-0 register (offset: 0x10) controlled by
DBI write-lock enable bit thereby not allowing any further writes to BAR-0
register in config space to take place. Hence disabling write permission
only towards the end.

Signed-off-by: Vidya Sagar <vidyas@xxxxxxxxxx>
---
Changes since [v1]:
* None

drivers/pci/controller/dwc/pcie-designware-host.c | 3 ---
1 file changed, 3 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 2a5332e5ccfa..c0334c92c1a6 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -683,7 +683,6 @@ void dw_pcie_setup_rc(struct pcie_port *pp)
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);
@@ -723,8 +722,6 @@ 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 */
--
2.7.4