On Nov 08, Bjorn Helgaas wrote: > On Fri, Nov 08, 2024 at 02:51:15AM +0000, Jianjun Wang (王建军) wrote: > > On Thu, 2024-11-07 at 10:21 -0600, Bjorn Helgaas wrote: > > > On Thu, Nov 07, 2024 at 05:08:55PM +0100, Lorenzo Bianconi wrote: > > > > > On Thu, Nov 07, 2024 at 02:50:55PM +0100, Lorenzo Bianconi wrote: > > > > > > In order to make the code more readable, move phy and mac > > > > > > reset lines assert/de-assert configuration in .power_up > > > > > > callback (mtk_pcie_en7581_power_up/mtk_pcie_power_up). > > > > > > > > ... > > > > > Is there a requirement that the PHY and MAC reset ordering be > > > > > different for EN7581 vs other chips? > > > > > > > > > > EN7581: > > > > > > > > > > assert PHY reset > > > > > assert MAC reset > > > > > power on PHY > > > > > deassert PHY reset > > > > > deassert MAC reset > > > > > > > > > > others: > > > > > > > > > > assert PHY reset > > > > > assert MAC reset > > > > > deassert PHY reset > > > > > power on PHY > > > > > deassert MAC reset > > > > > > > > > > Is there one order that would work for both? > > > > > > > > EN7581 requires to run phy_init()/phy_power_on() before deassert > > > > PHY reset lines. > > > > > > And the other chips require the PHY power-on to be *after* > > > deasserting PHY reset? > > > > For MediaTek's chips, the reset will clear all register values and > > reset the hardware state. Therefore, we can only initialize and > > power-on the MAC and PHY after deasserting their resets. > > OK, it sounds like you're saying the Airoha EN7581 is not a MediaTek > chip and does require a different ordering of PHY reset deassert and > PHY power-on: > > - EN7581 requires PHY power-on before PHY reset deassert, > > - other chips require PHY reset deassert before PHY power-on. > > That's fine and probably worth a short comment in > mtk_pcie_en7581_power_up(), e.g., "Unlike the MediaTek controllers, > the Airoha EN7581 requires PHY power-on before PHY reset deassert". > > Bjorn ack, I will add it. Regards, Lorenzo
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