lkml.org 
[lkml]   [2019]   [Aug]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v5 2/3] OPP: Add support for bandwidth OPP tables
On 07-08-19, 15:31, Saravana Kannan wrote:
> Not all devices quantify their performance points in terms of frequency.
> Devices like interconnects quantify their performance points in terms of
> bandwidth. We need a way to represent these bandwidth levels in OPP. So,
> add support for parsing bandwidth OPPs from DT.
>
> Signed-off-by: Saravana Kannan <saravanak@google.com>
> ---
> drivers/opp/of.c | 41 ++++++++++++++++++++++++++++++++---------
> drivers/opp/opp.h | 4 +++-
> 2 files changed, 35 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/opp/of.c b/drivers/opp/of.c
> index 1813f5ad5fa2..e1750033fef9 100644
> --- a/drivers/opp/of.c
> +++ b/drivers/opp/of.c
> @@ -523,6 +523,35 @@ void dev_pm_opp_of_remove_table(struct device *dev)
> }
> EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
>
> +static int _read_opp_key(struct dev_pm_opp *new_opp, struct device_node *np)
> +{
> + int ret;
> + u64 rate;
> + u32 bw;
> +
> + ret = of_property_read_u64(np, "opp-hz", &rate);
> + if (!ret) {
> + /*
> + * Rate is defined as an unsigned long in clk API, and so
> + * casting explicitly to its type. Must be fixed once rate is 64
> + * bit guaranteed in clk API.
> + */
> + new_opp->rate = (unsigned long)rate;
> + return 0;
> + }
> +

Please read opp-level also here and do error handling.

> + ret = of_property_read_u32(np, "opp-peak-kBps", &bw);
> + if (ret)
> + return ret;
> + new_opp->rate = (unsigned long) bw;
> +
> + ret = of_property_read_u32(np, "opp-avg-kBps", &bw);
> + if (!ret)
> + new_opp->avg_bw = (unsigned long) bw;

If none of opp-hz/level/peak-kBps are available, print error message here
itself..

> +
> + return 0;

You are returning 0 on failure as well here.

> +}
> +
> /**
> * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
> * @opp_table: OPP table
> @@ -560,22 +589,16 @@ static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
> if (!new_opp)
> return ERR_PTR(-ENOMEM);
>
> - ret = of_property_read_u64(np, "opp-hz", &rate);
> + ret = _read_opp_key(new_opp, np);
> if (ret < 0) {
> /* "opp-hz" is optional for devices like power domains. */
> if (!opp_table->is_genpd) {
> - dev_err(dev, "%s: opp-hz not found\n", __func__);
> + dev_err(dev, "%s: opp-hz or opp-peak-kBps not found\n",
> + __func__);
> goto free_opp;
> }
>
> rate_not_available = true;

Move all above as well to read_opp_key().

> - } else {
> - /*
> - * Rate is defined as an unsigned long in clk API, and so
> - * casting explicitly to its type. Must be fixed once rate is 64
> - * bit guaranteed in clk API.
> - */
> - new_opp->rate = (unsigned long)rate;
> }
>
> of_property_read_u32(np, "opp-level", &new_opp->level);
> diff --git a/drivers/opp/opp.h b/drivers/opp/opp.h
> index 01a500e2c40a..6bb238af9cac 100644
> --- a/drivers/opp/opp.h
> +++ b/drivers/opp/opp.h
> @@ -56,7 +56,8 @@ extern struct list_head opp_tables;
> * @turbo: true if turbo (boost) OPP
> * @suspend: true if suspend OPP
> * @pstate: Device's power domain's performance state.
> - * @rate: Frequency in hertz
> + * @rate: Frequency in hertz OR Peak bandwidth in kilobytes per second
> + * @avg_bw: Average bandwidth in kilobytes per second

Please add separate entry for peak_bw here.

I know you reused rate because you don't want to reimplement the helpers we
have. Maybe we can just update them to return peak_bw when opp-hz isn't present.

> * @level: Performance level
> * @supplies: Power supplies voltage/current values
> * @clock_latency_ns: Latency (in nanoseconds) of switching to this OPP's
> @@ -78,6 +79,7 @@ struct dev_pm_opp {
> bool suspend;
> unsigned int pstate;
> unsigned long rate;
> + unsigned long avg_bw;
> unsigned int level;
>
> struct dev_pm_opp_supply *supplies;
> --
> 2.23.0.rc1.153.gdeed80330f-goog

--
viresh

\
 
 \ /
  Last update: 2019-08-20 08:14    [W:0.134 / U:5.448 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site