On 2/15/22 11:23, Pali Rohár wrote:
If a PIO request is executed while link-down, the whole controller gets stuck in a non-functional state, and even after link comes up again, PIO requests won't work anymore, and a reset of the whole PCIe controller is needed. Therefore we need to prevent sending PIO requests while the link is down.
Signed-off-by: Pali Rohár pali@kernel.org
Reviewed-by: Stefan Roese sr@denx.de
Thanks, Stefan
drivers/pci/pci-aardvark.c | 38 +++++++++++++++++++++----------------- 1 file changed, 21 insertions(+), 17 deletions(-)
diff --git a/drivers/pci/pci-aardvark.c b/drivers/pci/pci-aardvark.c index 1eb257ea8b4a..ccaeecaca8e3 100644 --- a/drivers/pci/pci-aardvark.c +++ b/drivers/pci/pci-aardvark.c @@ -177,6 +177,23 @@ static inline uint advk_readl(struct pcie_advk *pcie, uint reg) return readl(pcie->base + reg); }
+/**
- pcie_advk_link_up() - Check if PCIe link is up or not
- @pcie: The PCI device to access
- Return true on link up.
- Return false on link down.
- */
+static bool pcie_advk_link_up(struct pcie_advk *pcie) +{
- u32 val, ltssm_state;
- val = advk_readl(pcie, ADVK_LMI_PHY_CFG0);
- ltssm_state = (val & ADVK_LMI_PHY_CFG0_LTSSM_MASK) >> ADVK_LMI_PHY_CFG0_LTSSM_SHIFT;
- return ltssm_state >= ADVK_LMI_PHY_CFG0_LTSSM_L0 && ltssm_state < ADVK_LMI_PHY_CFG0_LTSSM_DISABLED;
+}
- /**
- pcie_advk_addr_valid() - Check for valid bus address
@@ -195,6 +212,10 @@ static bool pcie_advk_addr_valid(struct pcie_advk *pcie, if (busno == 0 && (dev != 0 || func != 0)) return false;
- /* Access to other buses is possible when link is up */
- if (busno != 0 && !pcie_advk_link_up(pcie))
return false;- /*
- In PCI-E only a single device (0) can exist on the secondary bus.
- Beyond the secondary bus, there might be a Switch and anything is
@@ -618,23 +639,6 @@ retry: return ret; }
-/**
- pcie_advk_link_up() - Check if PCIe link is up or not
- @pcie: The PCI device to access
- Return 1 (true) on link up.
- Return 0 (false) on link down.
- */
-static int pcie_advk_link_up(struct pcie_advk *pcie) -{
- u32 val, ltssm_state;
- val = advk_readl(pcie, ADVK_LMI_PHY_CFG0);
- ltssm_state = (val & ADVK_LMI_PHY_CFG0_LTSSM_MASK) >> ADVK_LMI_PHY_CFG0_LTSSM_SHIFT;
- return ltssm_state >= ADVK_LMI_PHY_CFG0_LTSSM_L0 && ltssm_state < ADVK_LMI_PHY_CFG0_LTSSM_DISABLED;
-}
- /**
- pcie_advk_wait_for_link() - Wait for link training to be accomplished
Viele Grüße, Stefan Roese