Re: [PATCH net-next] r8169: add support for rtl8168h(revid 0x2a) + rtl8211fs fiber application

From: Andrew Lunn
Date: Thu Jul 21 2022 - 23:29:22 EST


> > +#define RT_SFP_ST (1)
> > +#define RT_SFP_OP_W (1)
> > +#define RT_SFP_OP_R (2)
> > +#define RT_SFP_TA_W (2)
> > +#define RT_SFP_TA_R (0)
> > +
> > +static void rtl_sfp_if_write(struct rtl8169_private *tp,
> > + struct rtl_sfp_if_mask *sfp_if_mask, u8 reg, u16 val)
> > +{
> > + struct rtl_sfp_if_info sfp_if_info = {0};
> > + const u16 mdc_reg = PIN_I_SEL_1;
> > + const u16 mdio_reg = PIN_I_SEL_2;
> > +
> > + rtl_select_sfp_if(tp, sfp_if_mask, &sfp_if_info);
> > +
> > + /* change to output mode */
> > + r8168_mac_ocp_write(tp, PINOE, sfp_if_info.mdio_oe_o);
> > +
> > + /* init sfp interface */
> > + r8168_mac_ocp_write(tp, mdc_reg, sfp_if_info.mdc_pd);
> > + r8168_mac_ocp_write(tp, mdio_reg, sfp_if_info.mdio_pu);
> > +
> > + /* preamble 32bit of 1 */
> > + rtl_sfp_shift_bit_in(tp, &sfp_if_info, 0xffffffff, 32);
> > +
> > + /* opcode write */
> > + rtl_sfp_shift_bit_in(tp, &sfp_if_info, RT_SFP_ST, 2);
> > + rtl_sfp_shift_bit_in(tp, &sfp_if_info, RT_SFP_OP_W, 2);
> > +
> > + /* phy address */
> > + rtl_sfp_shift_bit_in(tp, &sfp_if_info, sfp_if_mask->phy_addr, 5);
> > +
> > + /* phy reg */
> > + rtl_sfp_shift_bit_in(tp, &sfp_if_info, reg, 5);
> > +
> > + /* turn-around(TA) */
> > + rtl_sfp_shift_bit_in(tp, &sfp_if_info, RT_SFP_TA_W, 2);
> > +
> > + /* write phy data */
> > + rtl_sfp_shift_bit_in(tp, &sfp_if_info, val, 16);

This looks like a bit-banging MDIO bus? If so, please use the kernel
code, drivers/net/mdio/mdio-bitbang.c. You just need to provide it
with functions to write and read a bit, and it will do the rest,
including C45 which you don't seem to support here.

> > +static enum rtl_sfp_if_type rtl8168h_check_sfp(struct rtl8169_private *tp)
> > +{
> > + int i;
> > + int const checkcnt = 4;
> > +
> > + rtl_sfp_eeprom_write(tp, 0x1f, 0x0000);
> > + for (i = 0; i < checkcnt; i++) {
> > + if (rtl_sfp_eeprom_read(tp, 0x02) != RTL8211FS_PHY_ID_1 ||
> > + rtl_sfp_eeprom_read(tp, 0x03) != RTL8211FS_PHY_ID_2)
> > + break;
> > + }

Reading registers 2 and 3 for a PhY idea? Who not just use phylib, and
a PHY driver?

Andrew