| Message ID | 20220926115038.24727-9-vidyas@nvidia.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Lorenzo Pieralisi |
| Headers | show |
| Series | Enhancements to pcie-tegra194 driver | expand |
On Mon, Sep 26, 2022 at 05:20:37PM +0530, Vidya Sagar wrote: > Set ENABLE_L2_EXIT_RATE_CHANGE to request UPHY PLL rate change to Gen1 > during initialization. This helps in the below surprise down cases, > - Surprise down happens at Gen3/Gen4 link speed > - Surprise down happens and external REFCLK is cut off which causes > UPHY PLL rate to deviate to an invalid rate > > ENABLE_L2_EXIT_RATE_CHANGE needs to be set to bring the UPHY PLL rate > back to Gen1 during controller initialization for the link up. > > Signed-off-by: Vidya Sagar <vidyas@nvidia.com> > Reported-by: kernel test robot <lkp@intel.com> I doubt the kernel test robot reported the issue being fixed by this patch. More likely it reported a syntax or similar issue in v1, and I think the "reported-by" tag is meaningless in cases like that.
diff --git a/drivers/phy/tegra/phy-tegra194-p2u.c b/drivers/phy/tegra/phy-tegra194-p2u.c index 1415ca71de38..633e6b747275 100644 --- a/drivers/phy/tegra/phy-tegra194-p2u.c +++ b/drivers/phy/tegra/phy-tegra194-p2u.c @@ -15,6 +15,7 @@ #include <linux/phy/phy.h> #define P2U_CONTROL_CMN 0x74 +#define P2U_CONTROL_CMN_ENABLE_L2_EXIT_RATE_CHANGE BIT(13) #define P2U_CONTROL_CMN_SKP_SIZE_PROTECTION_EN BIT(20) #define P2U_PERIODIC_EQ_CTRL_GEN3 0xc0 @@ -85,8 +86,21 @@ static int tegra_p2u_power_on(struct phy *x) return 0; } +static int tegra_p2u_calibrate(struct phy *x) +{ + struct tegra_p2u *phy = phy_get_drvdata(x); + u32 val; + + val = p2u_readl(phy, P2U_CONTROL_CMN); + val |= P2U_CONTROL_CMN_ENABLE_L2_EXIT_RATE_CHANGE; + p2u_writel(phy, val, P2U_CONTROL_CMN); + + return 0; +} + static const struct phy_ops ops = { .power_on = tegra_p2u_power_on, + .calibrate = tegra_p2u_calibrate, .owner = THIS_MODULE, };
Set ENABLE_L2_EXIT_RATE_CHANGE to request UPHY PLL rate change to Gen1 during initialization. This helps in the below surprise down cases, - Surprise down happens at Gen3/Gen4 link speed - Surprise down happens and external REFCLK is cut off which causes UPHY PLL rate to deviate to an invalid rate ENABLE_L2_EXIT_RATE_CHANGE needs to be set to bring the UPHY PLL rate back to Gen1 during controller initialization for the link up. Signed-off-by: Vidya Sagar <vidyas@nvidia.com> Reported-by: kernel test robot <lkp@intel.com> --- V2: * Addressed review comment from test bot and Vinod drivers/phy/tegra/phy-tegra194-p2u.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)