Re: [PATCH v3 2/9] clk: ralink: add clock and reset driver for MTMIPS SoCs

From: Shiji Yang
Date: Sat Jun 17 2023 - 01:51:21 EST


Thank you for your quick reply!

>> >+ {
>> >+ .compatible = "ralink,mt7620a-sysc",
>> >+ .data = &mt7620_clk_data,
>> >+ },
>> >+ {
>> >+ .compatible = "ralink,mt7620-sysc",
>> >+ .data = &mt7620_clk_data,
>> >+ },
>> >+ {
>>
>> I am confused about the difference between `ralink,mt7620-sysc` and
>> `ralink,mt7620a-sysc`. Do you mean mt7620n?
>> https://www.mediatek.com/products/home-networking/mt7620n-a
>
>There is no real difference. As you can see both of them use the same
>'mt7620_clk_data' but since both compatible strings already exist
>somewhere I introduced both of them.
>

If they are the same, perhaps `mt7620a` also need to be checked in mtmips_clk_regs_init().
Or just remove compatible string of `mt7620a` and update dtsi files?

>+static void __init mtmips_clk_regs_init(struct device_node *node,
>+ struct mtmips_clk_priv *priv)
>+{
>+ u32 t;
>+
>+ if (!of_device_is_compatible(node, "ralink,mt7620-sysc"))
>+ return;
>+
>+ /*
>+ * When the CPU goes into sleep mode, the BUS
>+ * clock will be too low for USB to function properly.
>+ * Adjust the busses fractional divider to fix this
>+ */
>+ regmap_read(priv->sysc, SYSC_REG_CPU_SYS_CLKCFG, &t);
>+ t &= ~(CLKCFG_FDIV_MASK | CLKCFG_FFRAC_MASK);
>+ t |= CLKCFG_FDIV_USB_VAL | CLKCFG_FFRAC_USB_VAL;
>+ regmap_write(priv->sysc, SYSC_REG_CPU_SYS_CLKCFG, t);
>+}
>+

If we choose to update dts file. We can also remove the legacy
"ralink,rt2880-reset" compatible string by the way.

>+static const struct of_device_id mtmips_clk_of_match[] = {
>+ { .compatible = "ralink,rt2880-reset" },
>+ { .compatible = "ralink,rt2880-sysc" },
>+ { .compatible = "ralink,rt3050-sysc" },
>+ { .compatible = "ralink,rt3050-sysc" },
>+ { .compatible = "ralink,rt3352-sysc" },
>+ { .compatible = "ralink,rt3883-sysc" },
>+ { .compatible = "ralink,rt5350-sysc" },
>+ { .compatible = "ralink,mt7620a-sysc" },
>+ { .compatible = "ralink,mt7620-sysc" },
>+ { .compatible = "ralink,mt7628-sysc" },
>+ { .compatible = "ralink,mt7688-sysc" },
>+ {}
>+};

Thanks,
Shiji Yang