PCI: keystone: Fix link training retries initiation

[ Upstream commit 6df19872d881641e6394f93ef2938cffcbdae5bb ]

ks_pcie_stop_link() function does not clear LTSSM_EN_VAL bit so
link training was not triggered more than once after startup.
In configurations where link can be unstable during early boot,
for example, under low temperature, it will never be established.

Fixes: 0c4ffcfe1fbc ("PCI: keystone: Add TI Keystone PCIe driver")
Signed-off-by: Yurii Monakov <monakov.y@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Andrew Murray <andrew.murray@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/pci/controller/dwc/pci-keystone-dw.c b/drivers/pci/controller/dwc/pci-keystone-dw.c
index 0682213328e93ba2a000b4c67bb92736b0518228..15c612e853afbfc881413425afb33579e918c630 100644 (file)
--- a/drivers/pci/controller/dwc/pci-keystone-dw.c
+++ b/drivers/pci/controller/dwc/pci-keystone-dw.c
@@ -425,7 +425,7 @@ void ks_dw_pcie_initiate_link_train(struct keystone_pcie *ks_pcie)
        /* Disable Link training */
        val = ks_dw_app_readl(ks_pcie, CMD_STATUS);
        val &= ~LTSSM_EN_VAL;
-       ks_dw_app_writel(ks_pcie, CMD_STATUS, LTSSM_EN_VAL | val);
+       ks_dw_app_writel(ks_pcie, CMD_STATUS, val);
 
        /* Initiate Link Training */
        val = ks_dw_app_readl(ks_pcie, CMD_STATUS);