diff options
| author | Ajay Agarwal <ajayagarwal@google.com> | 2023-04-12 11:34:25 +0200 |
|---|---|---|
| committer | Lorenzo Pieralisi <lpieralisi@kernel.org> | 2023-05-26 10:45:12 +0200 |
| commit | da56a1bfbab55189595e588f1d984bdfb5cf5924 (patch) | |
| tree | 3b6bc5e11ca564f1349019af3e3d688da6866b70 | |
| parent | Linux 6.4-rc1 (diff) | |
| download | linux-da56a1bfbab55189595e588f1d984bdfb5cf5924.tar.xz linux-da56a1bfbab55189595e588f1d984bdfb5cf5924.zip | |
PCI: dwc: Wait for link up only if link is started
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.
Link: https://lore.kernel.org/r/20230412093425.3659088-1-ajayagarwal@google.com
Tested-by: Will McVicker <willmcvicker@google.com>
Signed-off-by: Sajid Dalvi <sdalvi@google.com>
Signed-off-by: Ajay Agarwal <ajayagarwal@google.com>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
| -rw-r--r-- | drivers/pci/controller/dwc/pcie-designware-host.c | 13 | ||||
| -rw-r--r-- | drivers/pci/controller/dwc/pcie-designware.c | 20 | ||||
| -rw-r--r-- | 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 8e33e6e59e68..df092229e97d 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) { |