[RFC PATCH 2/4] PCI: rockchip-host: Set Target Link Speed before retraining

Geraldo Nascimento
2025-06-07T11:05:15Z

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 accordingly.

Signed-off-by: Geraldo Nascimento <geraldogabriel@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 6a46be17aa91..55b3289fb70f 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_LCS_2);
+ status &= ~PCIE_RC_CONFIG_LCS_2_TLS_25;
+ status |= PCIE_RC_CONFIG_LCS_2_TLS_50;
+ rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_LCS_2);
status = rockchip_pcie_read(rockchip, PCIE_RC_CONFIG_LCS);
status |= PCI_EXP_LNKCTL_RL;
rockchip_pcie_write(rockchip, status, PCIE_RC_CONFIG_LCS);
--
2.49.0

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