lkml.org 
[lkml]   [2021]   [Dec]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 11/11] PCI: mvebu: Fix reporting Data Link Layer Link Active on emulated bridge
Date
Add support for reporting PCI_EXP_LNKSTA_DLLLA bit in Link Control register
on emulated bridge via PCIE_STAT_OFF reg. Function mvebu_pcie_link_up()
already parses this register and returns if Data Link is Active or not.

Also correctly indicate DLLLA capability via PCI_EXP_LNKCAP_DLLLARC bit in
Link Control Capability register which is required for reporting DLLLA bit.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
drivers/pci/controller/pci-mvebu.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c
index dffa330de174..a075ba26cff1 100644
--- a/drivers/pci/controller/pci-mvebu.c
+++ b/drivers/pci/controller/pci-mvebu.c
@@ -548,13 +548,18 @@ mvebu_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge,
/*
* PCIe requires that the Clock Power Management capability bit
* is hard-wired to zero for downstream ports but HW returns 1.
+ * Additionally enable Data Link Layer Link Active Reporting
+ * Capable bit as DL_Active indication is provided too.
*/
- *value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP) &
- ~PCI_EXP_LNKCAP_CLKPM;
+ *value = (mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP) &
+ ~PCI_EXP_LNKCAP_CLKPM) | PCI_EXP_LNKCAP_DLLLARC;
break;

case PCI_EXP_LNKCTL:
- *value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL);
+ /* DL_Active indication is provided via PCIE_STAT_OFF */
+ *value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL) |
+ (mvebu_pcie_link_up(port) ?
+ (PCI_EXP_LNKSTA_DLLLA << 16) : 0);
break;

case PCI_EXP_SLTCTL:
--
2.20.1
\
 
 \ /
  Last update: 2021-12-21 15:57    [W:0.355 / U:0.036 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site