[PATCH v3 2/4] PCI: tegra194: Avoid full Endpoint reinit on PERST#

[Manikanta Maddireddy <mmaddireddy@nvidia.com>]

Tegra194 and Tegra234 lose controller register state across PERST#, but
the driver remains bound. The common DWC initialization path now
restores those registers while preserving its software resources. Tegra
therefore no longer needs to call dw_pcie_ep_cleanup() on each PERST#
cycle.

Remove the per-reset dw_pcie_ep_cleanup() call. The existing
dw_pcie_ep_init_registers() entry point now restores reset-lost
registers after the first initialization while retaining software
resources until final driver teardown. The allocation guards already
reuse the bitmaps, address array and per-function descriptors; this
change also avoids repeating the full debugfs/eDMA teardown and setup.

Keep the EPF deinit notification in the PERST# deassert path after
REFCLK is available and core reset has been deasserted, because EPF
deinit callbacks can clear BARs and need register access. The final
dw_pcie_ep_deinit() during driver removal still performs full cleanup.

Signed-off-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>
---
Changes V2 -> V3:
- No code changes from v2; rebased onto the current PCI main-based stack.

Changes V1 -> V2:
- Keep the existing dw_pcie_ep_init_registers() call now that it handles
  both initial setup and reset recovery; only remove per-reset cleanup.
- Clarify the retained resource lifetimes and shorten the opening
  paragraph to focus on the Tegra change.

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

diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index 72158fc5c639..08d6f4c5220f 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -1909,7 +1909,6 @@ static void pex_ep_event_pex_rst_deassert(struct tegra_pcie_dw *pcie)
 
 	/* Perform cleanup that requires refclk and core reset deasserted */
 	pci_epc_deinit_notify(pcie->pci.ep.epc);
-	dw_pcie_ep_cleanup(&pcie->pci.ep);
 
 	val = dw_pcie_readl_dbi(pci, LINK_WIDTH_SPEED_CTRL);
 	val &= ~SPEED_CHANGE;
-- 
2.34.1