[PATCH v8 8/9] PCI: dw-rockchip: Set broken L1SS resume flag

[Sebastian Reichel]

During system suspend, the Rockchip RC driver effectively powers off the
controller. If the link is in L1SS and the endpoint asserts CLKREQ# to
exit L1SS, the time required to wake the system and restore the
PHY/REFCLK may exceed the L1SS exit timing (L10_REFCLK_ON +
T_COMMONMODE), resulting in Link Down (LDn) and a reset of the endpoint.
Set broken_l1ss_resume flag to indicate this limitation to the PCIe
framework. This results in pci_suspend_retains_context() returning false
and PCIe client can avoid relying on device state being preserved
during system suspend.

Reviewed-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
Signed-off-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx>
---
 drivers/pci/controller/dwc/pcie-dw-rockchip.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-dw-rockchip.c b/drivers/pci/controller/dwc/pcie-dw-rockchip.c
index 7933c50df340..9a2606748281 100644
--- a/drivers/pci/controller/dwc/pcie-dw-rockchip.c
+++ b/drivers/pci/controller/dwc/pcie-dw-rockchip.c
@@ -448,6 +448,11 @@ static int rockchip_pcie_host_init(struct dw_pcie_rp *pp)
 	return 0;
 }
 
+static void rockchip_pcie_host_post_init(struct dw_pcie_rp *pp)
+{
+	pp->bridge->broken_l1ss_resume = true;
+}
+
 static void rockchip_pcie_pme_turn_off(struct dw_pcie_rp *pp)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
@@ -487,6 +492,7 @@ static void rockchip_pcie_pme_turn_off(struct dw_pcie_rp *pp)
 
 static const struct dw_pcie_host_ops rockchip_pcie_host_ops = {
 	.init = rockchip_pcie_host_init,
+	.post_init = rockchip_pcie_host_post_init,
 	.pme_turn_off = rockchip_pcie_pme_turn_off,
 };
 

-- 
2.53.0