Re: [PATCH 1/2] remoteproc: qcom: Add bus scaling capability during bootup

[Mathieu Poirier]

On Mon, 30 Mar 2020 at 10:06, Mathieu Poirier
<mathieu.poirier@xxxxxxxxxx> wrote:
>
> Hi Rishabh,
>
> On Fri, 27 Mar 2020 at 18:59, Rishabh Bhatnagar <rishabhb@xxxxxxxxxxxxxx> wrote:
> >
> > During bootup since remote processors cannot request for
> > additional bus bandwidth from the interconect framework,
> > platform driver should provide the proxy resources. This
> > is useful for scenarios where the Q6 tries to access the DDR
> > memory in the initial stages of bootup. For e.g. during
> > bootup or after recovery modem Q6 tries to zero out the bss
> > section in the DDR. Since this is a big chunk of memory if
> > don't bump up the bandwidth we might encounter timeout issues.
> > This patch makes a proxy vote for maximizing the bus bandwidth
> > during bootup and removes it once processor is up.
> >
> > Signed-off-by: Rishabh Bhatnagar <rishabhb@xxxxxxxxxxxxxx>
>
> The title of this patch contains "[PATCH 1/2]" but only one patch was
> sent to the linux-remoteproc mailing list.  Is this a mistake and this
> is a stand alone patch or another patch did not reach the list?
>

I see that you sent another patch [1] that seems to be stand alone but
when looking into the code function of_icc_get() is called, which does
reference the bindings in [1].

[1]. https://patchwork.kernel.org/patch/11463381/

> Thanks,
> Mathieu
>
> > ---
> >  drivers/remoteproc/qcom_q6v5_pas.c | 43 +++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 42 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/remoteproc/qcom_q6v5_pas.c b/drivers/remoteproc/qcom_q6v5_pas.c
> > index edf9d0e..8f5db8d 100644
> > --- a/drivers/remoteproc/qcom_q6v5_pas.c
> > +++ b/drivers/remoteproc/qcom_q6v5_pas.c
> > @@ -20,6 +20,7 @@
> >  #include <linux/qcom_scm.h>
> >  #include <linux/regulator/consumer.h>
> >  #include <linux/remoteproc.h>
> > +#include <linux/interconnect.h>
> >  #include <linux/soc/qcom/mdt_loader.h>
> >  #include <linux/soc/qcom/smem.h>
> >  #include <linux/soc/qcom/smem_state.h>
> > @@ -28,6 +29,9 @@
> >  #include "qcom_q6v5.h"
> >  #include "remoteproc_internal.h"
> >
> > +#define PIL_TZ_AVG_BW  0
> > +#define PIL_TZ_PEAK_BW UINT_MAX
> > +
> >  struct adsp_data {
> >         int crash_reason_smem;
> >         const char *firmware_name;
> > @@ -62,6 +66,7 @@ struct qcom_adsp {
> >         int proxy_pd_count;
> >
> >         int pas_id;
> > +       struct icc_path *bus_client;
> >         int crash_reason_smem;
> >         bool has_aggre2_clk;
> >
> > @@ -124,6 +129,25 @@ static int adsp_load(struct rproc *rproc, const struct firmware *fw)
> >
> >  }
> >
> > +static int do_bus_scaling(struct qcom_adsp *adsp, bool enable)
> > +{
> > +       int rc;
> > +       u32 avg_bw = enable ? PIL_TZ_AVG_BW : 0;
> > +       u32 peak_bw = enable ? PIL_TZ_PEAK_BW : 0;
> > +
> > +       if (adsp->bus_client) {
> > +               rc = icc_set_bw(adsp->bus_client, avg_bw, peak_bw);
> > +               if (rc) {
> > +                       dev_err(adsp->dev, "bandwidth request failed(rc:%d)\n",
> > +                               rc);
> > +                       return rc;
> > +               }
> > +       } else
> > +               dev_info(adsp->dev, "Bus scaling not setup for %s\n",
> > +                       adsp->rproc->name);
> > +       return 0;
> > +}
> > +
> >  static int adsp_start(struct rproc *rproc)
> >  {
> >         struct qcom_adsp *adsp = (struct qcom_adsp *)rproc->priv;
> > @@ -131,9 +155,13 @@ static int adsp_start(struct rproc *rproc)
> >
> >         qcom_q6v5_prepare(&adsp->q6v5);
> >
> > +       ret = do_bus_scaling(adsp, true);
> > +       if (ret)
> > +               goto disable_irqs;
> > +
> >         ret = adsp_pds_enable(adsp, adsp->active_pds, adsp->active_pd_count);
> >         if (ret < 0)
> > -               goto disable_irqs;
> > +               goto unscale_bus;
> >
> >         ret = adsp_pds_enable(adsp, adsp->proxy_pds, adsp->proxy_pd_count);
> >         if (ret < 0)
> > @@ -183,6 +211,8 @@ static int adsp_start(struct rproc *rproc)
> >         adsp_pds_disable(adsp, adsp->proxy_pds, adsp->proxy_pd_count);
> >  disable_active_pds:
> >         adsp_pds_disable(adsp, adsp->active_pds, adsp->active_pd_count);
> > +unscale_bus:
> > +       do_bus_scaling(adsp, false);
> >  disable_irqs:
> >         qcom_q6v5_unprepare(&adsp->q6v5);
> >
> > @@ -198,6 +228,7 @@ static void qcom_pas_handover(struct qcom_q6v5 *q6v5)
> >         clk_disable_unprepare(adsp->aggre2_clk);
> >         clk_disable_unprepare(adsp->xo);
> >         adsp_pds_disable(adsp, adsp->proxy_pds, adsp->proxy_pd_count);
> > +       do_bus_scaling(adsp, false);
> >  }
> >
> >  static int adsp_stop(struct rproc *rproc)
> > @@ -280,6 +311,14 @@ static int adsp_init_regulator(struct qcom_adsp *adsp)
> >         return PTR_ERR_OR_ZERO(adsp->px_supply);
> >  }
> >
> > +static void adsp_init_bus_scaling(struct qcom_adsp *adsp)
> > +{
> > +       adsp->bus_client = of_icc_get(adsp->dev, NULL);
> > +       if (!adsp->bus_client)
> > +               dev_warn(adsp->dev, "%s: unable to get bus client \n",
> > +                       __func__);
> > +}
> > +
> >  static int adsp_pds_attach(struct device *dev, struct device **devs,
> >                            char **pd_names)
> >  {
> > @@ -410,6 +449,8 @@ static int adsp_probe(struct platform_device *pdev)
> >         if (ret)
> >                 goto free_rproc;
> >
> > +       adsp_init_bus_scaling(adsp);
> > +
> >         ret = adsp_pds_attach(&pdev->dev, adsp->active_pds,
> >                               desc->active_pd_names);
> >         if (ret < 0)
> > --
> > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> > a Linux Foundation Collaborative Project