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/host/pci-keystone-dw.c b/drivers/pci/host/pci-keystone-dw.c
index 6153853..988e7e7 100644 (file)
--- a/drivers/pci/host/pci-keystone-dw.c
+++ b/drivers/pci/host/pci-keystone-dw.c
@@ -450,7 +450,7 @@ void ks_dw_pcie_initiate_link_train(struct keystone_pcie *ks_pcie)
        /* Disable Link training */
        val = readl(ks_pcie->va_app_base + CMD_STATUS);
        val &= ~LTSSM_EN_VAL;
-       writel(LTSSM_EN_VAL | val,  ks_pcie->va_app_base + CMD_STATUS);
+       writel(val,  ks_pcie->va_app_base + CMD_STATUS);
 
        /* Initiate Link Training */
        val = readl(ks_pcie->va_app_base + CMD_STATUS);