From db845b9b2040f4ed5f8bce6cd30103e3b8557566 Mon Sep 17 00:00:00 2001 From: Andrew Halaney Date: Tue, 25 Jul 2023 16:04:26 -0500 Subject: [PATCH] net: stmmac: dwmac-qcom-ethqos: Use max frequency for clk_ptp_ref Qualcomm clocks can set their frequency to a variety of levels generally. Let's use the max for clk_ptp_ref to ensure the best timestamping resolution possible. Without this, the default value of the clock is used. For sa8775p-ride this is 19.2 MHz, far less than the 230.4 MHz possible. Reviewed-by: Simon Horman Signed-off-by: Andrew Halaney Link: https://lore.kernel.org/r/20230725211853.895832-4-ahalaney@redhat.com Signed-off-by: Jakub Kicinski --- .../stmicro/stmmac/dwmac-qcom-ethqos.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c index 735525ba8b931..a855018748011 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c @@ -694,6 +694,23 @@ static void ethqos_clks_disable(void *data) ethqos_clks_config(data, false); } +static void ethqos_ptp_clk_freq_config(struct stmmac_priv *priv) +{ + struct plat_stmmacenet_data *plat_dat = priv->plat; + int err; + + if (!plat_dat->clk_ptp_ref) + return; + + /* Max the PTP ref clock out to get the best resolution possible */ + err = clk_set_rate(plat_dat->clk_ptp_ref, ULONG_MAX); + if (err) + netdev_err(priv->dev, "Failed to max out clk_ptp_ref: %d\n", err); + plat_dat->clk_ptp_rate = clk_get_rate(plat_dat->clk_ptp_ref); + + netdev_dbg(priv->dev, "PTP rate %d\n", plat_dat->clk_ptp_rate); +} + static int qcom_ethqos_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; @@ -779,6 +796,7 @@ static int qcom_ethqos_probe(struct platform_device *pdev) plat_dat->bsp_priv = ethqos; plat_dat->fix_mac_speed = ethqos_fix_mac_speed; plat_dat->dump_debug_regs = rgmii_dump; + plat_dat->ptp_clk_freq_config = ethqos_ptp_clk_freq_config; plat_dat->has_gmac4 = 1; if (ethqos->has_emac_ge_3) plat_dat->dwmac4_addrs = &data->dwmac4_addrs; -- 2.30.2