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net: stmmac: dwmac-qcom-ethqos: Enable RGMII functional clock on resume

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When the Qualcomm ethqos driver is properly described in its associated
GDSC power-domain, the hardware will be powered down and loose its state
between qcom_ethqos_probe() and stmmac_init_dma_engine().

The result of this is that the functional clock from the RGMII IO macro
is no longer provides and the DMA software reset in dwmac4_dma_reset()
will time out, due to lacking clock signal.

Re-enable the functional clock, as part of the Qualcomm specific clock
enablement sequence to avoid this problem.

The final clock configuration will be adjusted by ethqos_fix_mac_speed()
once the link is being brought up.

Fixes: a7c30e62d4 ("net: stmmac: Add driver for Qualcomm ethqos")
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Tested-and-reviewed-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
Link: https://lore.kernel.org/r/20220323033255.2282930-1-bjorn.andersson@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Bjorn Andersson 2022-03-22 20:32:55 -07:00 committed by Jakub Kicinski
parent 169e77764a
commit ffba2123e1
1 changed files with 7 additions and 0 deletions
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7
drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
View File

@ -487,6 +487,13 @@ static int ethqos_clks_config(void *priv, bool enabled)
dev_err(&ethqos->pdev->dev, "rgmii_clk enable failed\n");
return ret;
}
/* Enable functional clock to prevent DMA reset to timeout due
* to lacking PHY clock after the hardware block has been power
* cycled. The actual configuration will be adjusted once
* ethqos_fix_mac_speed() is invoked.
*/
ethqos_set_func_clk_en(ethqos);
} else {
clk_disable_unprepare(ethqos->rgmii_clk);
}