[RFC PATCH v3 3/5] PCI: rockchip-host: Set Target Link Speed before retraining

Geraldo Nascimento geraldogabriel at gmail.com
Thu Jun 12 22:21:53 PDT 2025


Current code may fail Gen2 retraining if Target Link Speed
is set to 2.5 GT/s in Link Control and Status Register 2.
Set it to 5.0 GT/s accordingly.

Signed-off-by: Geraldo Nascimento <geraldogabriel at gmail.com>
---
 drivers/pci/controller/pcie-rockchip-host.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/pci/controller/pcie-rockchip-host.c b/drivers/pci/controller/pcie-rockchip-host.c
index 65653218b9ab..68634ae8caaf 100644
--- a/drivers/pci/controller/pcie-rockchip-host.c
+++ b/drivers/pci/controller/pcie-rockchip-host.c
@@ -341,6 +341,10 @@ static int rockchip_pcie_host_init_port(struct rockchip_pcie *rockchip)
 		 * Enable retrain for gen2. This should be configured only after
 		 * gen1 finished.
 		 */
+		status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL2);
+		status |= FIELD_PREP(PCI_EXP_LNKCTL2_TLS, PCI_EXP_LNKCTL2_TLS_5_0GT);
+		rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL2);
+
 		status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
 		status |= PCI_EXP_LNKCTL_RL;
 		rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_CR + PCI_EXP_LNKCTL);
-- 
2.49.0




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