[PATCH v2] PCI: dwc: Use the correct sleep function in wait_for_link

From: Konrad Dybcio
Date: Wed Mar 27 2024 - 14:25:02 EST


According to [1], msleep should be used for large sleeps, such as the
100-ish ms one in this function. Comply with the guide and use it.

[1] https://www.kernel.org/doc/Documentation/timers/timers-howto.txt

Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
---
Tested on Qualcomm SC8280XP CRD
---
Changes in v2:
- Rename the define
- Sleep for 90ms (the lower boundary) instead of 100
- Link to v1: https://lore.kernel.org/r/20240215-topic-pci_sleep-v1-1-7ac79ac9739a@xxxxxxxxxx
---
drivers/pci/controller/dwc/pcie-designware.c | 2 +-
drivers/pci/controller/dwc/pcie-designware.h | 3 +--
2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index 250cf7f40b85..62915e4b2ebd 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -655,7 +655,7 @@ int dw_pcie_wait_for_link(struct dw_pcie *pci)
if (dw_pcie_link_up(pci))
break;

- usleep_range(LINK_WAIT_USLEEP_MIN, LINK_WAIT_USLEEP_MAX);
+ msleep(LINK_WAIT_SLEEP_MS);
}

if (retries >= LINK_WAIT_MAX_RETRIES) {
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 26dae4837462..b17e8ff54f55 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -63,8 +63,7 @@

/* Parameters for the waiting for link up routine */
#define LINK_WAIT_MAX_RETRIES 10
-#define LINK_WAIT_USLEEP_MIN 90000
-#define LINK_WAIT_USLEEP_MAX 100000
+#define LINK_WAIT_SLEEP_MS 90

/* Parameters for the waiting for iATU enabled routine */
#define LINK_WAIT_MAX_IATU_RETRIES 5

---
base-commit: 26074e1be23143b2388cacb36166766c235feb7c
change-id: 20240215-topic-pci_sleep-368108a1fb6f

Best regards,
--
Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>