Re: [PATCH v3 02/19] clk: tegra: simplify periph clock data
From: Peter De Schrijver
Date: Wed Oct 16 2013 - 11:06:26 EST
On Tue, Oct 15, 2013 at 08:46:21PM +0200, Stephen Warren wrote:
> On 10/15/2013 08:52 AM, Peter De Schrijver wrote:
> > This patch determines the register bank for clock enable/disable and reset
> > based on the clock ID instead of hardcoding it in the tables describing the
> > clocks. This results in less data to be maintained in the tables, making the
> > code easier to understand. The full benefit of the change will be realized once
> > also other clocktypes will be table based.
>
> > diff --git a/drivers/clk/tegra/clk-tegra114.c b/drivers/clk/tegra/clk-tegra114.c
>
> > #define TEGRA_INIT_DATA_MUX(_name, _con_id, _dev_id, _parents, _offset, \
> > - _clk_num, _regs, _gate_flags, _clk_id) \
> > + _clk_num, _gate_flags, _clk_id) \
> > TEGRA_INIT_DATA_TABLE(_name, _con_id, _dev_id, _parents, _offset,\
> > - 30, MASK(2), 0, 0, 8, 1, 0, _regs, _clk_num, \
> > - periph_clk_enb_refcnt, _gate_flags, _clk_id, \
> > - _parents##_idx, 0)
> > + 30, MASK(2), 0, 0, 8, 1, 0, \
> > + _clk_num, periph_clk_enb_refcnt, _gate_flags,\
> > + _clk_id, _parents##_idx, 0)
>
> Nit (since there are bugs since I know V4 is needed): If you kept
> _clk_num on the same line in that macro, the diff would be much more
> obvious. I think I said this last time.
>
> > for (i = 0; i < ARRAY_SIZE(tegra_periph_clk_list); i++) {
> > data = &tegra_periph_clk_list[i];
> > - clk = tegra_clk_register_periph(data->name, data->parent_names,
> > - data->num_parents, &data->periph,
> > - clk_base, data->offset, data->flags);
> > +
> > + clk = tegra_clk_register_periph(data->name,
> > + data->parent_names, data->num_parents, &data->periph,
> > + clk_base, data->offset, data->flags);
> > clks[data->clk_id] = clk;
> > }
> >
> > for (i = 0; i < ARRAY_SIZE(tegra_periph_nodiv_clk_list); i++) {
> > data = &tegra_periph_nodiv_clk_list[i];
> > +
> > clk = tegra_clk_register_periph_nodiv(data->name,
>
> Nit: Seems like an unrelated change, and inconsistent with the other
> loop above.
>
Actually it makes it consistent. The previous loop added an empty line
between data = ... and tegra_clk_register_periph()
> > diff --git a/drivers/clk/tegra/clk.c b/drivers/clk/tegra/clk.c
>
> > +struct tegra_clk_periph_regs * __init get_reg_bank(int clkid)
> > +{
> > + int reg_bank = clkid / 32;
> > +
> > + if (reg_bank < periph_banks)
> > + return &periph_regs[reg_bank];
> > + else {
> > + WARN_ON(1);
> > + return NULL;
> > + }
> > +}
> > +
> > +int __init tegra_clk_periph_banks(int num)
> > +{
> > + if (num > ARRAY_SIZE(periph_regs))
> > + return -EINVAL;
> > +
> > + periph_banks = num;
> > +
> > + return 0;
> > +}
>
> Shouldn't the condition in tegra_clk_periph_banks() check against
> periph_banks rather than ARRAY_SIZE(periph_regs)? I assume the calls to
periph_banks is initialized in tegra_clk_periph_banks(), so I don't see how
that would work?
> tegra_clk_periph_banks() from tegra*_clock_init() are intended to ensure
> that periph_regs is set up correctly in this file? I wonder if
> s/tegra_clk_periph_banks/tegra_clk_validate_periph_bank_count/ isn't
> called for?
Yes. The calls are intended to ensure that the clk-tegra* files, don't
refer to register banks which don't have addresses specified. This could happen
if a wrong periph clk ID would be specified for example. In later patches
we will also allocate memory based on the number of register banks.
Cheers,
Peter.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/