In dw_pcie_host_init() regardless of whether the link has been
started or not, the code waits for the link to come up. Even in
cases where start_link() is not defined the code ends up spinning
in a loop for 1 second. Since in some systems dw_pcie_host_init()
gets called during probe, this one second loop for each pcie
interface instance ends up extending the boot time.
Wait for the link up in only if the start_link() is defined.
Signed-off-by: Sajid Dalvi <sdalvi@xxxxxxxxxx>
Signed-off-by: Ajay Agarwal <ajayagarwal@xxxxxxxxxx>
---
Changelog since v3:
- Run dw_pcie_start_link() only if link is not already up
Changelog since v2:
- Wait for the link up if start_link() is really defined.
- Print the link status if the link is up on init.
.../pci/controller/dwc/pcie-designware-host.c | 13 ++++++++----
drivers/pci/controller/dwc/pcie-designware.c | 20 ++++++++++++-------
drivers/pci/controller/dwc/pcie-designware.h | 1 +
3 files changed, 23 insertions(+), 11 deletions(-)
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 9952057c8819..cf61733bf78d 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -485,14 +485,19 @@ int dw_pcie_host_init(struct dw_pcie_rp *pp)
if (ret)
goto err_remove_edma;
- if (!dw_pcie_link_up(pci)) {
+ if (dw_pcie_link_up(pci)) {
+ dw_pcie_print_link_status(pci);
+ } else {
ret = dw_pcie_start_link(pci);
if (ret)
goto err_remove_edma;
- }
- /* Ignore errors, the link may come up later */
- dw_pcie_wait_for_link(pci);
+ if (pci->ops && pci->ops->start_link) {
+ ret = dw_pcie_wait_for_link(pci);
+ if (ret)
+ goto err_stop_link;
+ }
+ }
bridge->sysdata = pp;
diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index 53a16b8b6ac2..03748a8dffd3 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -644,9 +644,20 @@ void dw_pcie_disable_atu(struct dw_pcie *pci, u32 dir, int index)
dw_pcie_writel_atu(pci, dir, index, PCIE_ATU_REGION_CTRL2, 0);
}
-int dw_pcie_wait_for_link(struct dw_pcie *pci)
+void dw_pcie_print_link_status(struct dw_pcie *pci)
{
u32 offset, val;
+
+ offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
+ val = dw_pcie_readw_dbi(pci, offset + PCI_EXP_LNKSTA);
+
+ dev_info(pci->dev, "PCIe Gen.%u x%u link up\n",
+ FIELD_GET(PCI_EXP_LNKSTA_CLS, val),
+ FIELD_GET(PCI_EXP_LNKSTA_NLW, val));
+}
+
+int dw_pcie_wait_for_link(struct dw_pcie *pci)
+{
int retries;
/* Check if the link is up or not */
@@ -662,12 +673,7 @@ int dw_pcie_wait_for_link(struct dw_pcie *pci)
return -ETIMEDOUT;
}
- offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
- val = dw_pcie_readw_dbi(pci, offset + PCI_EXP_LNKSTA);
-
- dev_info(pci->dev, "PCIe Gen.%u x%u link up\n",
- FIELD_GET(PCI_EXP_LNKSTA_CLS, val),
- FIELD_GET(PCI_EXP_LNKSTA_NLW, val));
+ dw_pcie_print_link_status(pci);
return 0;
}
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 79713ce075cc..615660640801 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -429,6 +429,7 @@ void dw_pcie_setup(struct dw_pcie *pci);
void dw_pcie_iatu_detect(struct dw_pcie *pci);
int dw_pcie_edma_detect(struct dw_pcie *pci);
void dw_pcie_edma_remove(struct dw_pcie *pci);
+void dw_pcie_print_link_status(struct dw_pcie *pci);
static inline void dw_pcie_writel_dbi(struct dw_pcie *pci, u32 reg, u32 val)
{
--
2.40.0.577.gac1e443424-goog
