[PATCH v2 2/2] PCI: designware: let dw_pcie_link_up() beware of LTSSM training bit
From: pratyush.anand@gmail.com (Pratyush Anand)
Date: 2016-08-14 16:17:40
Also in:
linux-pci, lkml
On Wed, Aug 10, 2016 at 11:01 AM, Jisheng Zhang [off-list ref] wrote:
The link may be UP but still in link training. In this case, we can't think the link is up and operating correctly. So we need to teach dw_pcie_link_up() beware of the PCIE_PHY_DEBUG_R1_LINK_IN_TRAINING bit.
I have no more access of designware PCIe specification now. Since Joao has acked it, so I would consider that PCIE_PHY_DEBUG_R1_LINK_IN_TRAINING bit exists in older core as well. If it is there then you have my Acked-by too. ~Pratyush
quoted hunk ↗ jump to hunk
This patch also rewrite PCIE_PHY_DEBUG_R1_LINK_UP definition so that it's consistent with other MACROS. Signed-off-by: Jisheng Zhang <redacted> Acked-by: Joao Pinto <redacted> --- drivers/pci/host/pcie-designware.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c index 24a16dd..6cc21bb 100644 --- a/drivers/pci/host/pcie-designware.c +++ b/drivers/pci/host/pcie-designware.c@@ -73,7 +73,8 @@ /* PCIe Port Logic registers */ #define PLR_OFFSET 0x700 #define PCIE_PHY_DEBUG_R1 (PLR_OFFSET + 0x2c) -#define PCIE_PHY_DEBUG_R1_LINK_UP 0x00000010 +#define PCIE_PHY_DEBUG_R1_LINK_UP (0x1 << 4) +#define PCIE_PHY_DEBUG_R1_LINK_IN_TRAINING (0x1 << 29) /* Parameters for the waiting for link up routine */ #define LINK_WAIT_MAX_RETRIES 10@@ -417,7 +418,8 @@ int dw_pcie_link_up(struct pcie_port *pp) return pp->ops->link_up(pp); val = readl(pp->dbi_base + PCIE_PHY_DEBUG_R1); - return val & PCIE_PHY_DEBUG_R1_LINK_UP; + return ((val & PCIE_PHY_DEBUG_R1_LINK_UP) && + (!(val & PCIE_PHY_DEBUG_R1_LINK_IN_TRAINING))); } static int dw_pcie_msi_map(struct irq_domain *domain, unsigned int irq, --2.8.1