On Tue, Jan 08, 2019 at 03:30:22PM +0200, Tero Kristo wrote:
> Currently the sci-clk driver queries clock data from the firmware, which
> can be pretty slow operation in certain cases. Add an option for the
> driver to probe the available clocks from DT also, in this case the
> number of clocks probed from firmware gets cut down drastically. To
> enable the feature, a new flag ti,scan-clocks-from-dt can be added
> under the clock provider node.
>
> Signed-off-by: Tero Kristo <t-kristo@xxxxxx>
> Tested-by: Andreas Dannenberg <dannenberg@xxxxxx>
> ---
> drivers/clk/keystone/sci-clk.c | 188 ++++++++++++++++++++++++++++++++++-------
> 1 file changed, 159 insertions(+), 29 deletions(-)
> +static int ti_sci_scan_clocks_from_dt(struct sci_clk_provider *provider)
> +{
> + struct device *dev = provider->dev;
> + struct device_node *np = NULL;
> + int ret;
> + int index;
> + struct of_phandle_args args;
> + struct list_head clks;
> + struct sci_clk *sci_clk, *prev;
> + int num_clks = 0;
> + int num_parents;
> + int clk_id;
> +
> + INIT_LIST_HEAD(&clks);
> +
> + while (1) {
> + np = of_find_node_with_property(np, "clocks");
> + if (!np)
> + break;
for_each_node_with_property
> +
> + index = 0;
> +
> + do {
> + ret = of_parse_phandle_with_args(np, "clocks",
> + "#clock-cells", index,
> + &args);
> + if (ret)
> + break;
of_for_each_phandle can be used here. And then of_phandle_iterator_args
will get the args.
> +
> + if (args.args_count == 2 && args.np == dev->of_node) {
dtc will warn if the # of cells are wrong, so that's probably redundant.
Invert the if and save a level of indentation.
> + sci_clk = devm_kzalloc(dev, sizeof(*sci_clk),
> + GFP_KERNEL);
> + if (!sci_clk)
> + return -ENOMEM;
> +
> + sci_clk->dev_id = args.args[0];
> + sci_clk->clk_id = args.args[1];
> + sci_clk->provider = provider;
> + provider->ops->
> + get_num_parents(provider->sci,
> + sci_clk->dev_id,
> + sci_clk->clk_id,
> + &sci_clk->num_parents);
> + list_add_tail(&sci_clk->node, &clks);
> +
> + num_clks++;
> +
> + num_parents = sci_clk->num_parents;
> + if (num_parents == 1)
> + num_parents = 0;
> +
> + clk_id = args.args[1] + 1;
> +
> + while (num_parents--) {
> + sci_clk = devm_kzalloc(dev,
> + sizeof(*sci_clk),
> + GFP_KERNEL);
> + if (!sci_clk)
> + return -ENOMEM;
> + sci_clk->dev_id = args.args[0];
> + sci_clk->clk_id = clk_id++;
> + sci_clk->provider = provider;
> + list_add_tail(&sci_clk->node, &clks);
> +
> + num_clks++;
> + }
> + }
> +
> + index++;
> + } while (args.np);
> + }
> +
> + list_sort(NULL, &clks, _cmp_sci_clk_list);
> +
> + provider->clocks = devm_kmalloc_array(dev, num_clks, sizeof(sci_clk),
> + GFP_KERNEL);
> + if (!provider->clocks)
> + return -ENOMEM;
> +
> + num_clks = 0;
> + prev = NULL;
> +
> + list_for_each_entry(sci_clk, &clks, node) {
> + if (prev && prev->dev_id == sci_clk->dev_id &&
> + prev->clk_id == sci_clk->clk_id)
> + continue;
> +
> + provider->clocks[num_clks++] = sci_clk;
> + prev = sci_clk;
> + }
> +
> + provider->num_clocks = num_clks;
> +
> + return 0;
> +}
