[PATCH rtems-libbsd 2/3] freebsd/cgem: Read clock frequency from device tree

[Padmarao.Begari at microchip.com]

Hi will,

> On Wed, 2023-03-01 at 08:20 -0600, Will wrote:
>  	
> On Tue, Feb 28, 2023 at 11:57 PM Padmarao Begari <
> padmarao.begari at microchip.com> wrote:
> > Read the clock frequency from the device tree and use it to
> > calculate the mdc clock divider for the MII bus if not found
> > then use default clock divider.
> > ---
> >  freebsd/sys/dev/cadence/if_cgem.c | 39
> > ++++++++++++++++++++++++++++---
> >  1 file changed, 36 insertions(+), 3 deletions(-)
> > 
> > diff --git a/freebsd/sys/dev/cadence/if_cgem.c
> > b/freebsd/sys/dev/cadence/if_cgem.c
> > index 2888a085..363a9717 100644
> > --- a/freebsd/sys/dev/cadence/if_cgem.c
> > +++ b/freebsd/sys/dev/cadence/if_cgem.c
> > @@ -135,6 +135,7 @@ struct cgem_softc {
> >         uint32_t                net_cfg_shadow;
> >         int                     neednullqs;
> >         int                     phy_contype;
> > +       uint32_t                pclk_rate;
> >  #endif /* __rtems__ */
> >         int                     ref_clk_num;
> >  #ifndef __rtems__
> > @@ -1238,6 +1239,27 @@ cgem_get_phyaddr(phandle_t node, int
> > *phy_addr)
> >         return (0);
> >  }
> > 
> > +static uint32_t cgem_mdc_clk_div(struct cgem_softc *sc)
> > +{
> > +       uint32_t config;
> > +       uint32_t pclk_hz = sc->pclk_rate;
> > +
> > +       if (pclk_hz <= 20000000)
> > +               config = CGEM_NET_CFG_MDC_CLK_DIV_8;
> > +       else if (pclk_hz <= 40000000)
> > +               config = CGEM_NET_CFG_MDC_CLK_DIV_16;
> > +       else if (pclk_hz <= 80000000)
> > +               config = CGEM_NET_CFG_MDC_CLK_DIV_32;
> > +       else if (pclk_hz <= 120000000)
> > +               config = CGEM_NET_CFG_MDC_CLK_DIV_48;
> > +       else if (pclk_hz <= 160000000)
> > +               config = CGEM_NET_CFG_MDC_CLK_DIV_64;
> > +       else
> > +               config = CGEM_NET_CFG_MDC_CLK_DIV_96;
> > +
> > +       return config;
> > +}
> > +
> > 
> 
> Enclose this in a #ifdef __rtems__ guard. I think the suggested style
> is to always use braces {} with if/else, even if it's a single line.
>  
Ok, will update

Regards
Padmarao
> >  /* Reset hardware. */
> >  static void
> >  cgem_reset(struct cgem_softc *sc)
> > @@ -1279,12 +1301,16 @@ cgem_reset(struct cgem_softc *sc)
> >                 sc->net_cfg_shadow = CGEM_NET_CFG_DBUS_WIDTH_32;
> >         }
> > 
> > +       if (sc->pclk_rate != 0) {
> > +               sc->net_cfg_shadow |= cgem_mdc_clk_div(sc);
> > +       } else {
> >  #ifdef CGEM64
> > -       sc->net_cfg_shadow |= CGEM_NET_CFG_MDC_CLK_DIV_48;
> > +               sc->net_cfg_shadow |= CGEM_NET_CFG_MDC_CLK_DIV_48;
> >  #else
> > -       sc->net_cfg_shadow |= CGEM_NET_CFG_MDC_CLK_DIV_64;
> > +               sc->net_cfg_shadow |= CGEM_NET_CFG_MDC_CLK_DIV_64;
> >  #endif
> > -       WR4(sc, CGEM_NET_CFG, sc->net_cfg_shadow);
> > +               WR4(sc, CGEM_NET_CFG, sc->net_cfg_shadow);
> > +       }
> >  #endif /* __rtems__ */
> > 
> >         sc->net_ctl_shadow = CGEM_NET_CTRL_MGMT_PORT_EN;
> > @@ -2038,6 +2064,13 @@ cgem_attach(device_t dev)
> >  #endif /* __rtems__ */
> >         /* Get reference clock number and base divider from fdt. */
> >         node = ofw_bus_get_node(dev);
> > +#ifdef __rtems__
> > +       if (OF_getencprop(node, "clock-frequency", &cell,
> > sizeof(cell)) > 0)
> > +               sc->pclk_rate = cell;
> > +       else
> > +               sc->pclk_rate = 0;
> > +#endif /* __rtems__ */
> > +
> >         sc->ref_clk_num = 0;
> >         if (OF_getprop(node, "ref-clock-num", &cell, sizeof(cell))
> > > 0)
> >                 sc->ref_clk_num = fdt32_to_cpu(cell);