Airoha EN7581 has a hw bug asserting/releasing PCIE_PE_RSTB signal causing occasional PCIe link down issues. In order to overcome the problem, PCIe block is reset using REG_PCI_CONTROL (0x88) and REG_RESET_CONTROL (0x834) registers available in the clock module running clk_bulk_prepare_enable() in mtk_pcie_en7581_power_up(). In order to make the code more readable, move the wait for the time needed to complete the PCIe reset from en7581_pci_enable() to mtk_pcie_en7581_power_up(). Reduce reset timeout from 250ms to the standard PCIE_T_PVPERL_MS value (100ms) since it has no impact on the driver behavior. Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx> Acked-by: Stephen Boyd <sboyd@xxxxxxxxxx> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx> --- drivers/clk/clk-en7523.c | 1 - drivers/pci/controller/pcie-mediatek-gen3.c | 7 +++++++ 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/clk/clk-en7523.c b/drivers/clk/clk-en7523.c index e52c5460e927f54c6df152c60560f438f89ec928..513730e5b953f4412b6b12b98c742692de5424c1 100644 --- a/drivers/clk/clk-en7523.c +++ b/drivers/clk/clk-en7523.c @@ -477,7 +477,6 @@ static int en7581_pci_enable(struct clk_hw *hw) REG_PCI_CONTROL_PERSTOUT; val = readl(np_base + REG_PCI_CONTROL); writel(val | mask, np_base + REG_PCI_CONTROL); - msleep(250); return 0; } diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c index 71df8817c1635b04b67233fb43abe2de7770b0f2..01e0b53cc1f22fc4b9270a2eb6a55e8948ba2f8b 100644 --- a/drivers/pci/controller/pcie-mediatek-gen3.c +++ b/drivers/pci/controller/pcie-mediatek-gen3.c @@ -974,6 +974,13 @@ static int mtk_pcie_en7581_power_up(struct mtk_gen3_pcie *pcie) goto err_clk_prepare_enable; } + /* + * Airoha EN7581 performs PCIe reset via clk callbacks since it has a + * hw issue with PCIE_PE_RSTB signal. Add wait for the time needed to + * complete the PCIe reset. + */ + msleep(PCIE_T_PVPERL_MS); + return 0; err_clk_prepare_enable: -- 2.47.1
