Subject: Re: [PATCH 06/11] clk: rp1: Add support for clocks provided by RP1

From: Andrea della Porta <[email-masked]>
Date: Thu, 22 Aug 2024 12:04:34 +0200

Hi Simon,

On 14:17 Wed 21 Aug     , Simon Horman wrote:
> On Tue, Aug 20, 2024 at 04:36:08PM +0200, Andrea della Porta wrote:
> > RaspberryPi RP1 is an MFD providing, among other peripherals, several
> > clock generators and PLLs that drives the sub-peripherals.
> > Add the driver to support the clock providers.
> > 
> > Signed-off-by: Andrea della Porta <[email-masked]>
> 
> ...
> 
> > diff --git a/drivers/clk/clk-rp1.c b/drivers/clk/clk-rp1.c
> > new file mode 100644
> > index 000000000000..d18e711c0623
> > --- /dev/null
> > +++ b/drivers/clk/clk-rp1.c
> > @@ -0,0 +1,1655 @@
> > +// SPDX-License-Identifier: GPL
> 
> checkpatch says:
> 
> WARNING: 'SPDX-License-Identifier: GPL' is not supported in LICENSES/...
>

Alas, the system on which I executed checkpatch was missing git python module,
so spdxcheck.py wasn't working properly, sorry about that. Fixed in the next
release.

> ...
> 
> > +static int rp1_clock_set_parent(struct clk_hw *hw, u8 index)
> > +{
> > +	struct rp1_clock *clock = container_of(hw, struct rp1_clock, hw);
> > +	struct rp1_clockman *clockman = clock->clockman;
> > +	const struct rp1_clock_data *data = clock->data;
> > +	u32 ctrl, sel;
> > +
> > +	spin_lock(&clockman->regs_lock);
> > +	ctrl = clockman_read(clockman, data->ctrl_reg);
> > +
> > +	if (index >= data->num_std_parents) {
> > +		/* This is an aux source request */
> > +		if (index >= data->num_std_parents + data->num_aux_parents)
> 
> It looks like &clockman->regs_lock needs to be unlocked here.
> 
> Flagged by Smatch, Sparse. and Coccinelle.

Ack.

Many thanks,
Andrea

> 
> > +			return -EINVAL;
> > +
> > +		/* Select parent from aux list */
> > +		ctrl = set_register_field(ctrl, index - data->num_std_parents,
> > +					  CLK_CTRL_AUXSRC_MASK,
> > +					  CLK_CTRL_AUXSRC_SHIFT);
> > +		/* Set src to aux list */
> > +		ctrl = set_register_field(ctrl, AUX_SEL, data->clk_src_mask,
> > +					  CLK_CTRL_SRC_SHIFT);
> > +	} else {
> > +		ctrl = set_register_field(ctrl, index, data->clk_src_mask,
> > +					  CLK_CTRL_SRC_SHIFT);
> > +	}
> > +
> > +	clockman_write(clockman, data->ctrl_reg, ctrl);
> > +	spin_unlock(&clockman->regs_lock);
> > +
> > +	sel = rp1_clock_get_parent(hw);
> > +	WARN(sel != index, "(%s): Parent index req %u returned back %u\n",
> > +	     data->name, index, sel);
> > +
> > +	return 0;
> > +}
> 
> ...