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Merge branch 'remotes/lorenzo/pci/mediatek'

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- Assert PERST# for 100ms to allow power and clock to stabilize (qizhong
  cheng)

* remotes/lorenzo/pci/mediatek:
  PCI: mediatek: Assert PERST# for 100ms for power and clock to stabilize
This commit is contained in:
Bjorn Helgaas 2022-01-13 09:57:48 -06:00
commit fd785c64f3
1 changed files with 7 additions and 0 deletions
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7
drivers/pci/controller/pcie-mediatek.c
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@ -702,6 +702,13 @@ static int mtk_pcie_startup_port_v2(struct mtk_pcie_port *port)
*/
writel(PCIE_LINKDOWN_RST_EN, port->base + PCIE_RST_CTRL);
/*
* Described in PCIe CEM specification sections 2.2 (PERST# Signal) and
* 2.2.1 (Initial Power-Up (G3 to S0)). The deassertion of PERST# should
* be delayed 100ms (TPVPERL) for the power and clock to become stable.
*/
msleep(100);
/* De-assert PHY, PE, PIPE, MAC and configuration reset */
val = readl(port->base + PCIE_RST_CTRL);
val |= PCIE_PHY_RSTB | PCIE_PERSTB | PCIE_PIPE_SRSTB |