[RFT net-next v4 1/5] net: stmmac: dwmac-meson8b: only configure the clocks in RGMII mode
Martin Blumenstingl
martin.blumenstingl at googlemail.com
Mon Jan 15 04:04:50 PST 2018
Hi Jerome,
On Mon, Jan 15, 2018 at 12:46 PM, Jerome Brunet <jbrunet at baylibre.com> wrote:
> On Sun, 2018-01-14 at 22:48 +0100, Martin Blumenstingl wrote:
>>
>
> [...]
>
>> @@ -204,12 +200,24 @@ static int meson8b_init_prg_eth(struct meson8b_dwmac *dwmac)
>>
>> meson8b_dwmac_mask_bits(dwmac, PRG_ETH0, PRG_ETH0_TXDLY_MASK,
>> tx_dly_val << PRG_ETH0_TXDLY_SHIFT);
>> +
>> + ret = clk_prepare_enable(dwmac->m25_div_clk);
>> + if (ret) {
>> + dev_err(&dwmac->pdev->dev, "failed to enable the PHY clock\n");
>> + return ret;
>> + }
>> +
>> + /* Generate the 25MHz RGMII clock for the PHY */
>> + ret = clk_set_rate(dwmac->m25_div_clk, 25 * 1000 * 1000);
>> + if (ret) {
>> + clk_disable_unprepare(dwmac->m25_div_clk);
>> +
>> + dev_err(&dwmac->pdev->dev, "failed to set PHY clock\n");
>> + return ret;
>> + }
>> break;
>>
>> case PHY_INTERFACE_MODE_RMII:
>> - /* Use the rate of the mux clock for the internal RMII PHY */
>> - clk_rate = clk_get_rate(dwmac->m250_mux_clk);
>> -
>> /* disable RGMII mode -> enables RMII mode */
>> meson8b_dwmac_mask_bits(dwmac, PRG_ETH0, PRG_ETH0_RGMII_MODE,
>> 0);
>> @@ -231,20 +239,6 @@ static int meson8b_init_prg_eth(struct meson8b_dwmac *dwmac)
>> return -EINVAL;
>> }
>>
>> - ret = clk_prepare_enable(dwmac->m25_div_clk);
>> - if (ret) {
>> - dev_err(&dwmac->pdev->dev, "failed to enable the PHY clock\n");
>> - return ret;
>> - }
>> -
>> - ret = clk_set_rate(dwmac->m25_div_clk, clk_rate);
>> - if (ret) {
>> - clk_disable_unprepare(dwmac->m25_div_clk);
>> -
>> - dev_err(&dwmac->pdev->dev, "failed to set PHY clock\n");
>> - return ret;
>> - }
>> -
>
> I would set the rate first then enable. Less chances of glitches and no need to
> call clk_disable_unprepare if it fails
I did swap the calls in PATCH #3 of this series
with this patch I wanted to make sure that all of the current logic is
only executed in RGMII mode
>> /* enable TX_CLK and PHY_REF_CLK generator */
>> meson8b_dwmac_mask_bits(dwmac, PRG_ETH0, PRG_ETH0_TX_AND_PHY_REF_CLK,
>> PRG_ETH0_TX_AND_PHY_REF_CLK);
>> @@ -294,7 +288,7 @@ static int meson8b_dwmac_probe(struct platform_device *pdev)
>> &dwmac->tx_delay_ns))
>> dwmac->tx_delay_ns = 2;
>>
>> - ret = meson8b_init_clk(dwmac);
>> + ret = meson8b_init_rgmii_tx_clk(dwmac);
>> if (ret)
>> goto err_remove_config_dt;
>>
>> @@ -311,7 +305,8 @@ static int meson8b_dwmac_probe(struct platform_device *pdev)
>> return 0;
>>
>> err_clk_disable:
>> - clk_disable_unprepare(dwmac->m25_div_clk);
>> + if (phy_interface_mode_is_rgmii(dwmac->phy_mode))
>> + clk_disable_unprepare(dwmac->m25_div_clk);
>> err_remove_config_dt:
>> stmmac_remove_config_dt(pdev, plat_dat);
>>
>> @@ -322,7 +317,8 @@ static int meson8b_dwmac_remove(struct platform_device *pdev)
>> {
>> struct meson8b_dwmac *dwmac = get_stmmac_bsp_priv(&pdev->dev);
>>
>> - clk_disable_unprepare(dwmac->m25_div_clk);
>> + if (phy_interface_mode_is_rgmii(dwmac->phy_mode))
>> + clk_disable_unprepare(dwmac->m25_div_clk);
>
> if you use
> devm_add_action_or_reset(dev, (void(*)(void *))clk_disable_unprepare,
>  YOUR-CLK)
>
> after enabling the clock, your can discard these conditional hunks.
noted, I'll also make this part of the clock cleanup series
>>
>> return stmmac_pltfr_remove(pdev);
>> }
>
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