diff options
Diffstat (limited to 'drivers/pci/controller/dwc/pcie-rcar-gen4.c')
| -rw-r--r-- | drivers/pci/controller/dwc/pcie-rcar-gen4.c | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c index 18055807a4f5..c16c4c2be499 100644 --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c @@ -182,8 +182,17 @@ static int rcar_gen4_pcie_common_init(struct rcar_gen4_pcie *rcar) return ret; } - if (!reset_control_status(dw->core_rsts[DW_PCIE_PWR_RST].rstc)) + if (!reset_control_status(dw->core_rsts[DW_PCIE_PWR_RST].rstc)) { reset_control_assert(dw->core_rsts[DW_PCIE_PWR_RST].rstc); + /* + * R-Car V4H Reference Manual R19UH0186EJ0130 Rev.1.30 Apr. + * 21, 2025 page 585 Figure 9.3.2 Software Reset flow (B) + * indicates that for peripherals in HSC domain, after + * reset has been asserted by writing a matching reset bit + * into register SRCR, it is mandatory to wait 1ms. + */ + fsleep(1000); + } val = readl(rcar->base + PCIEMSR0); if (rcar->drvdata->mode == DW_PCIE_RC_TYPE) { @@ -204,6 +213,19 @@ static int rcar_gen4_pcie_common_init(struct rcar_gen4_pcie *rcar) if (ret) goto err_unprepare; + /* + * Assure the reset is latched and the core is ready for DBI access. + * On R-Car V4H, the PCIe reset is asynchronous and does not take + * effect immediately, but needs a short time to complete. In case + * DBI access happens in that short time, that access generates an + * SError. To make sure that condition can never happen, read back the + * state of the reset, which should turn the asynchronous reset into + * synchronous one, and wait a little over 1ms to add additional + * safety margin. + */ + reset_control_status(dw->core_rsts[DW_PCIE_PWR_RST].rstc); + fsleep(1000); + if (rcar->drvdata->additional_common_init) rcar->drvdata->additional_common_init(rcar); @@ -711,7 +733,7 @@ static int rcar_gen4_pcie_ltssm_control(struct rcar_gen4_pcie *rcar, bool enable val &= ~APP_HOLD_PHY_RST; writel(val, rcar->base + PCIERSTCTRL1); - ret = readl_poll_timeout(rcar->phy_base + 0x0f8, val, !(val & BIT(18)), 100, 10000); + ret = readl_poll_timeout(rcar->phy_base + 0x0f8, val, val & BIT(18), 100, 10000); if (ret < 0) return ret; |