[U-Boot] [PATCH 1/4] clk: sifive: Add clock driver for GEMGXL MGMT

[Bin Meng]

Hi Lukas,

On Mon, May 20, 2019 at 7:26 PM Auer, Lukas
<lukas.auer at aisec.fraunhofer.de> wrote:
>
> Hi Bin,
>
> On Thu, 2019-05-16 at 02:12 -0700, Bin Meng wrote:
> > This adds a clock driver to support the GEMGXL management IP block
> > found in FU540 SoCs to control GEM TX clock operation mode for
> > 10/100/1000 Mbps.
> >
> > Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
> > ---
> >
> >  drivers/clk/sifive/Kconfig       |  7 +++++
> >  drivers/clk/sifive/Makefile      |  2 ++
> >  drivers/clk/sifive/gemgxl-mgmt.c | 60 ++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 69 insertions(+)
> >  create mode 100644 drivers/clk/sifive/gemgxl-mgmt.c
> >
> > diff --git a/drivers/clk/sifive/Kconfig b/drivers/clk/sifive/Kconfig
> > index 81fc9f8..644881b 100644
> > --- a/drivers/clk/sifive/Kconfig
> > +++ b/drivers/clk/sifive/Kconfig
> > @@ -17,3 +17,10 @@ config CLK_SIFIVE_FU540_PRCI
> >         Supports the Power Reset Clock interface (PRCI) IP block found in
> >         FU540 SoCs.  If this kernel is meant to run on a SiFive FU540 SoC,
> >         enable this driver.
> > +
> > +config CLK_SIFIVE_GEMGXL_MGMT
> > +     bool "GEMGXL management for SiFive FU540 SoCs"
> > +     depends on CLK_SIFIVE
> > +     help
> > +       Supports the GEMGXL management IP block found in FU540 SoCs to
> > +       control GEM TX clock operation mode for 10/100/1000 Mbps.
> > diff --git a/drivers/clk/sifive/Makefile b/drivers/clk/sifive/Makefile
> > index 1155e07..f8263e7 100644
> > --- a/drivers/clk/sifive/Makefile
> > +++ b/drivers/clk/sifive/Makefile
> > @@ -3,3 +3,5 @@
> >  obj-$(CONFIG_CLK_ANALOGBITS_WRPLL_CLN28HPC)  += wrpll-cln28hpc.o
> >
> >  obj-$(CONFIG_CLK_SIFIVE_FU540_PRCI)          += fu540-prci.o
> > +
> > +obj-$(CONFIG_CLK_SIFIVE_GEMGXL_MGMT)         += gemgxl-mgmt.o
> > diff --git a/drivers/clk/sifive/gemgxl-mgmt.c b/drivers/clk/sifive/gemgxl-mgmt.c
> > new file mode 100644
> > index 0000000..d989989
> > --- /dev/null
> > +++ b/drivers/clk/sifive/gemgxl-mgmt.c
> > @@ -0,0 +1,60 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * Copyright (C) 2019, Bin Meng <bmeng.cn at gmail.com>
> > + */
> > +
> > +#include <common.h>
> > +#include <clk-uclass.h>
> > +#include <dm.h>
> > +#include <asm/io.h>
> > +
> > +struct gemgxl_mgmt_regs {
> > +     __u32 tx_clk_sel;
> > +};
> > +
> > +struct gemgxl_mgmt_platdata {
> > +     struct gemgxl_mgmt_regs *regs;
> > +};
> > +
> > +static int gemgxl_mgmt_ofdata_to_platdata(struct udevice *dev)
> > +{
> > +     struct gemgxl_mgmt_platdata *plat = dev_get_platdata(dev);
> > +
> > +     plat->regs = (struct gemgxl_mgmt_regs *)dev_read_addr(dev);
> > +
> > +     return 0;
> > +}
> > +
> > +static ulong gemgxl_mgmt_set_rate(struct clk *clk, ulong rate)
> > +{
> > +     struct gemgxl_mgmt_platdata *plat = dev_get_platdata(clk->dev);
> > +
> > +     /*
> > +      * GEMGXL TX clock operation mode:
> > +      *
> > +      * 0 = GMII mode. Use 125 MHz gemgxlclk from PRCI in TX logic
> > +      *     and output clock on GMII output signal GTX_CLK
> > +      * 1 = MII mode. Use MII input signal TX_CLK in TX logic
> > +      */
> > +     writel(rate != 125000000, &plat->regs->tx_clk_sel);
> > +
> > +     return 0;
> > +}
> > +
> > +const struct clk_ops gemgxl_mgmt_ops = {
> > +     .set_rate = gemgxl_mgmt_set_rate,
> > +};
> > +
> > +static const struct udevice_id gemgxl_mgmt_match[] = {
> > +     { .compatible = "sifive,cadencegemgxlmgmt0", },
> > +     { /* sentinel */ }
> > +};
> > +
> > +U_BOOT_DRIVER(gemgxl_mgmt) = {
> > +     .name = "gemgxl-mgmt",
>
> nit: should the driver maybe be named sifive-gemgxl-mgmt to indicate
> that it is a SiFive-specific driver?

Will rename the driver in v2.

>
> Looks good otherwise!
>
> Reviewed-by: Lukas Auer <lukas.auer at aisec.fraunhofer.de>
> Tested-by: Lukas Auer <lukas.auer at aisec.fraunhofer.de>
>

Regards,
Bin