[PATCH V4 06/22] PCI: tegra194: Disable direct speed change for EP

Manikanta Maddireddy posted 22 patches 2 weeks ago
[PATCH V4 06/22] PCI: tegra194: Disable direct speed change for EP
Posted by Manikanta Maddireddy 2 weeks ago
From: Vidya Sagar <vidyas@nvidia.com>

Disable direct speed change for the endpoint to prevent it from initiating
the speed change post physical layer link up at gen1. This leaves the speed
change ownership with the host.

Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>
---
V4:
* None

V3:
* Reworded the commit message

V2:
* None

 drivers/pci/controller/dwc/pcie-tegra194.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index d3d577d5f67b..25f933a578ae 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -1841,6 +1841,10 @@ static void pex_ep_event_pex_rst_deassert(struct tegra_pcie_dw *pcie)
 
 	reset_control_deassert(pcie->core_rst);
 
+	val = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
+	val &= ~PORT_LOGIC_SPEED_CHANGE;
+	dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, val);
+
 	if (pcie->update_fc_fixup) {
 		val = dw_pcie_readl_dbi(pci, CFG_TIMER_CTRL_MAX_FUNC_NUM_OFF);
 		val |= 0x1 << CFG_TIMER_CTRL_ACK_NAK_SHIFT;
-- 
2.34.1