diff mbox series

[next,v2,3/6] usb: xhci-mtk: update fs bus bandwidth by bw_budget_table

Message ID 20210826025144.51992-3-chunfeng.yun@mediatek.com (mailing list archive)
State New, archived
Headers show
Series [next,v2,1/6] Revert "usb: xhci-mtk: relax TT periodic bandwidth allocation" | expand

Commit Message

Chunfeng Yun Aug. 26, 2021, 2:51 a.m. UTC
Use @bw_budget_table[] to update fs bus bandwidth due to
not all microframes consume @bw_cost_per_microframe, see
setup_sch_info().

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
---
v2: new patch, move from another series
---
 drivers/usb/host/xhci-mtk-sch.c | 17 +++++++----------
 1 file changed, 7 insertions(+), 10 deletions(-)

Comments

Ikjoon Jang Aug. 26, 2021, 11:54 a.m. UTC | #1
Hi Chunfeng,

On Thu, Aug 26, 2021 at 10:52 AM Chunfeng Yun <chunfeng.yun@mediatek.com> wrote:
>
> Use @bw_budget_table[] to update fs bus bandwidth due to
> not all microframes consume @bw_cost_per_microframe, see
> setup_sch_info().
>
> Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
> ---
> v2: new patch, move from another series
> ---
>  drivers/usb/host/xhci-mtk-sch.c | 17 +++++++----------
>  1 file changed, 7 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/usb/host/xhci-mtk-sch.c b/drivers/usb/host/xhci-mtk-sch.c
> index cffcaf4dfa9f..83abd28269ca 100644
> --- a/drivers/usb/host/xhci-mtk-sch.c
> +++ b/drivers/usb/host/xhci-mtk-sch.c
> @@ -458,8 +458,8 @@ static int check_fs_bus_bw(struct mu3h_sch_ep_info *sch_ep, int offset)
>                  * Compared with hs bus, no matter what ep type,
>                  * the hub will always delay one uframe to send data
>                  */
> -               for (j = 0; j < sch_ep->cs_count; j++) {
> -                       tmp = tt->fs_bus_bw[base + j] + sch_ep->bw_cost_per_microframe;
> +               for (j = 0; j < sch_ep->num_budget_microframes; j++) {
> +                       tmp = tt->fs_bus_bw[base + j] + sch_ep->bw_budget_table[j];

I'm worrying about this case with two endpoints,
* EP1OUT: isochronous, maxpacket=192: bw_budget_table[] = { 188, 188, 0, ... }
* EP2IN: interrupt, maxpacket=64: bw_budget_table[] = { 0, 0, 64, 64, ... }
(Is this correct bw_budget_table contents for those eps?)

I'm not sure if it's okay for those two endpoints to be allocated
on the same u-frame slot.
Can you please check if this is okay for xhci-mtk?
(I feel like I already asked the same questions many times.)


>                         if (tmp > FS_PAYLOAD_MAX)
>                                 return -ESCH_BW_OVERFLOW;
>                 }
> @@ -534,21 +534,18 @@ static void update_sch_tt(struct mu3h_sch_ep_info *sch_ep, bool used)
>  {
>         struct mu3h_sch_tt *tt = sch_ep->sch_tt;
>         u32 base, num_esit;
> -       int bw_updated;
>         int i, j;
>
>         num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
>
> -       if (used)
> -               bw_updated = sch_ep->bw_cost_per_microframe;
> -       else
> -               bw_updated = -sch_ep->bw_cost_per_microframe;
> -
>         for (i = 0; i < num_esit; i++) {
>                 base = sch_ep->offset + i * sch_ep->esit;
>
> -               for (j = 0; j < sch_ep->cs_count; j++)
> -                       tt->fs_bus_bw[base + j] += bw_updated;
> +               for (j = 0; j < sch_ep->num_budget_microframes; j++)
> +                       if (used)
> +                               tt->fs_bus_bw[base + j] += sch_ep->bw_budget_table[j];
> +                       else
> +                               tt->fs_bus_bw[base + j] -= sch_ep->bw_budget_table[j];
>         }
>
>         if (used)
> --
> 2.18.0
>
Chunfeng Yun Aug. 27, 2021, 6:49 a.m. UTC | #2
On Thu, 2021-08-26 at 19:54 +0800, Ikjoon Jang wrote:
> Hi Chunfeng,
> 
> On Thu, Aug 26, 2021 at 10:52 AM Chunfeng Yun <
> chunfeng.yun@mediatek.com> wrote:
> > 
> > Use @bw_budget_table[] to update fs bus bandwidth due to
> > not all microframes consume @bw_cost_per_microframe, see
> > setup_sch_info().
> > 
> > Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
> > ---
> > v2: new patch, move from another series
> > ---
> >  drivers/usb/host/xhci-mtk-sch.c | 17 +++++++----------
> >  1 file changed, 7 insertions(+), 10 deletions(-)
> > 
> > diff --git a/drivers/usb/host/xhci-mtk-sch.c
> > b/drivers/usb/host/xhci-mtk-sch.c
> > index cffcaf4dfa9f..83abd28269ca 100644
> > --- a/drivers/usb/host/xhci-mtk-sch.c
> > +++ b/drivers/usb/host/xhci-mtk-sch.c
> > @@ -458,8 +458,8 @@ static int check_fs_bus_bw(struct
> > mu3h_sch_ep_info *sch_ep, int offset)
> >                  * Compared with hs bus, no matter what ep type,
> >                  * the hub will always delay one uframe to send
> > data
> >                  */
> > -               for (j = 0; j < sch_ep->cs_count; j++) {
> > -                       tmp = tt->fs_bus_bw[base + j] + sch_ep-
> > >bw_cost_per_microframe;
> > +               for (j = 0; j < sch_ep->num_budget_microframes;
> > j++) {
> > +                       tmp = tt->fs_bus_bw[base + j] + sch_ep-
> > >bw_budget_table[j];
> 
> I'm worrying about this case with two endpoints,
> * EP1OUT: isochronous, maxpacket=192: bw_budget_table[] = { 188, 188,
> 0, ... }
> * EP2IN: interrupt, maxpacket=64: bw_budget_table[] = { 0, 0, 64, 64,
> ... }
> (Is this correct bw_budget_table contents for those eps?)
Yes, ep1out isoc use two uframe, ep2in intr use a extra cs;
> 
> I'm not sure if it's okay for those two endpoints to be allocated
> on the same u-frame slot.
> Can you please check if this is okay for xhci-mtk?
Already test it this afternoon, can transfer data rightly on our dvt
env.

> (I feel like I already asked the same questions many times.)
Yes, as said before, prefer to use bw_budget_table[], if there is
issue, we can fix it by building this table.

Thanks
> 
> 
> >                         if (tmp > FS_PAYLOAD_MAX)
> >                                 return -ESCH_BW_OVERFLOW;
> >                 }
> > @@ -534,21 +534,18 @@ static void update_sch_tt(struct
> > mu3h_sch_ep_info *sch_ep, bool used)
> >  {
> >         struct mu3h_sch_tt *tt = sch_ep->sch_tt;
> >         u32 base, num_esit;
> > -       int bw_updated;
> >         int i, j;
> > 
> >         num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
> > 
> > -       if (used)
> > -               bw_updated = sch_ep->bw_cost_per_microframe;
> > -       else
> > -               bw_updated = -sch_ep->bw_cost_per_microframe;
> > -
> >         for (i = 0; i < num_esit; i++) {
> >                 base = sch_ep->offset + i * sch_ep->esit;
> > 
> > -               for (j = 0; j < sch_ep->cs_count; j++)
> > -                       tt->fs_bus_bw[base + j] += bw_updated;
> > +               for (j = 0; j < sch_ep->num_budget_microframes;
> > j++)
> > +                       if (used)
> > +                               tt->fs_bus_bw[base + j] += sch_ep-
> > >bw_budget_table[j];
> > +                       else
> > +                               tt->fs_bus_bw[base + j] -= sch_ep-
> > >bw_budget_table[j];
> >         }
> > 
> >         if (used)
> > --
> > 2.18.0
> >
Ikjoon Jang Aug. 27, 2021, 9:14 a.m. UTC | #3
On Fri, Aug 27, 2021 at 2:49 PM Chunfeng Yun (云春峰)
<Chunfeng.Yun@mediatek.com> wrote:
>
> On Thu, 2021-08-26 at 19:54 +0800, Ikjoon Jang wrote:
> > Hi Chunfeng,
> >
> > On Thu, Aug 26, 2021 at 10:52 AM Chunfeng Yun <
> > chunfeng.yun@mediatek.com> wrote:
> > >
> > > Use @bw_budget_table[] to update fs bus bandwidth due to
> > > not all microframes consume @bw_cost_per_microframe, see
> > > setup_sch_info().
> > >
> > > Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
> > > ---
> > > v2: new patch, move from another series
> > > ---
> > >  drivers/usb/host/xhci-mtk-sch.c | 17 +++++++----------
> > >  1 file changed, 7 insertions(+), 10 deletions(-)
> > >
> > > diff --git a/drivers/usb/host/xhci-mtk-sch.c
> > > b/drivers/usb/host/xhci-mtk-sch.c
> > > index cffcaf4dfa9f..83abd28269ca 100644
> > > --- a/drivers/usb/host/xhci-mtk-sch.c
> > > +++ b/drivers/usb/host/xhci-mtk-sch.c
> > > @@ -458,8 +458,8 @@ static int check_fs_bus_bw(struct
> > > mu3h_sch_ep_info *sch_ep, int offset)
> > >                  * Compared with hs bus, no matter what ep type,
> > >                  * the hub will always delay one uframe to send
> > > data
> > >                  */
> > > -               for (j = 0; j < sch_ep->cs_count; j++) {
> > > -                       tmp = tt->fs_bus_bw[base + j] + sch_ep-
> > > >bw_cost_per_microframe;
> > > +               for (j = 0; j < sch_ep->num_budget_microframes;
> > > j++) {
> > > +                       tmp = tt->fs_bus_bw[base + j] + sch_ep-
> > > >bw_budget_table[j];
> >
> > I'm worrying about this case with two endpoints,
> > * EP1OUT: isochronous, maxpacket=192: bw_budget_table[] = { 188, 188,
> > 0, ... }
> > * EP2IN: interrupt, maxpacket=64: bw_budget_table[] = { 0, 0, 64, 64,
> > ... }
> > (Is this correct bw_budget_table contents for those eps?)
> Yes, ep1out isoc use two uframe, ep2in intr use a extra cs;
> >
> > I'm not sure if it's okay for those two endpoints to be allocated
> > on the same u-frame slot.
> > Can you please check if this is okay for xhci-mtk?
> Already test it this afternoon, can transfer data rightly on our dvt
> env.
>
> > (I feel like I already asked the same questions many times.)
> Yes, as said before, prefer to use bw_budget_table[], if there is
> issue, we can fix it by building this table.

So do you mean such an allocation shouldn't be a problem by IP design?

This patch starts to allow such an allocation (again).
But i remember my earlier tests showed that when those two eps
in the above example are allocated on the same u-frame slot,
xhci-mtk puts "SSPLIT for EP2" between
"SSPLIT-start and SSPLIT-end for EP1OUT transaction",
which is a spec violation. Hub will generate bit stuffing errors on the
full-speed bus.


>
> Thanks
> >
> >
> > >                         if (tmp > FS_PAYLOAD_MAX)
> > >                                 return -ESCH_BW_OVERFLOW;
> > >                 }
> > > @@ -534,21 +534,18 @@ static void update_sch_tt(struct
> > > mu3h_sch_ep_info *sch_ep, bool used)
> > >  {
> > >         struct mu3h_sch_tt *tt = sch_ep->sch_tt;
> > >         u32 base, num_esit;
> > > -       int bw_updated;
> > >         int i, j;
> > >
> > >         num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
> > >
> > > -       if (used)
> > > -               bw_updated = sch_ep->bw_cost_per_microframe;
> > > -       else
> > > -               bw_updated = -sch_ep->bw_cost_per_microframe;
> > > -
> > >         for (i = 0; i < num_esit; i++) {
> > >                 base = sch_ep->offset + i * sch_ep->esit;
> > >
> > > -               for (j = 0; j < sch_ep->cs_count; j++)
> > > -                       tt->fs_bus_bw[base + j] += bw_updated;
> > > +               for (j = 0; j < sch_ep->num_budget_microframes;
> > > j++)
> > > +                       if (used)
> > > +                               tt->fs_bus_bw[base + j] += sch_ep-
> > > >bw_budget_table[j];
> > > +                       else
> > > +                               tt->fs_bus_bw[base + j] -= sch_ep-
> > > >bw_budget_table[j];
> > >         }
> > >
> > >         if (used)
> > > --
> > > 2.18.0
> > >
Chunfeng Yun Aug. 27, 2021, 9:48 a.m. UTC | #4
On Fri, 2021-08-27 at 17:14 +0800, Ikjoon Jang wrote:
> On Fri, Aug 27, 2021 at 2:49 PM Chunfeng Yun (云春峰)
> <Chunfeng.Yun@mediatek.com> wrote:
> > 
> > On Thu, 2021-08-26 at 19:54 +0800, Ikjoon Jang wrote:
> > > Hi Chunfeng,
> > > 
> > > On Thu, Aug 26, 2021 at 10:52 AM Chunfeng Yun <
> > > chunfeng.yun@mediatek.com> wrote:
> > > > 
> > > > Use @bw_budget_table[] to update fs bus bandwidth due to
> > > > not all microframes consume @bw_cost_per_microframe, see
> > > > setup_sch_info().
> > > > 
> > > > Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
> > > > ---
> > > > v2: new patch, move from another series
> > > > ---
> > > >  drivers/usb/host/xhci-mtk-sch.c | 17 +++++++----------
> > > >  1 file changed, 7 insertions(+), 10 deletions(-)
> > > > 
> > > > diff --git a/drivers/usb/host/xhci-mtk-sch.c
> > > > b/drivers/usb/host/xhci-mtk-sch.c
> > > > index cffcaf4dfa9f..83abd28269ca 100644
> > > > --- a/drivers/usb/host/xhci-mtk-sch.c
> > > > +++ b/drivers/usb/host/xhci-mtk-sch.c
> > > > @@ -458,8 +458,8 @@ static int check_fs_bus_bw(struct
> > > > mu3h_sch_ep_info *sch_ep, int offset)
> > > >                  * Compared with hs bus, no matter what ep
> > > > type,
> > > >                  * the hub will always delay one uframe to send
> > > > data
> > > >                  */
> > > > -               for (j = 0; j < sch_ep->cs_count; j++) {
> > > > -                       tmp = tt->fs_bus_bw[base + j] + sch_ep-
> > > > > bw_cost_per_microframe;
> > > > 
> > > > +               for (j = 0; j < sch_ep->num_budget_microframes;
> > > > j++) {
> > > > +                       tmp = tt->fs_bus_bw[base + j] + sch_ep-
> > > > > bw_budget_table[j];
> > > 
> > > I'm worrying about this case with two endpoints,
> > > * EP1OUT: isochronous, maxpacket=192: bw_budget_table[] = { 188,
> > > 188,
> > > 0, ... }
> > > * EP2IN: interrupt, maxpacket=64: bw_budget_table[] = { 0, 0, 64,
> > > 64,
> > > ... }
> > > (Is this correct bw_budget_table contents for those eps?)
> > 
> > Yes, ep1out isoc use two uframe, ep2in intr use a extra cs;
> > > 
> > > I'm not sure if it's okay for those two endpoints to be allocated
> > > on the same u-frame slot.
> > > Can you please check if this is okay for xhci-mtk?
> > 
> > Already test it this afternoon, can transfer data rightly on our
> > dvt
> > env.
> > 
> > > (I feel like I already asked the same questions many times.)
> > 
> > Yes, as said before, prefer to use bw_budget_table[], if there is
> > issue, we can fix it by building this table.
> 
> So do you mean such an allocation shouldn't be a problem by IP
> design?
Yes, at least on our dvt platform

> 
> This patch starts to allow such an allocation (again).
> But i remember my earlier tests showed that when those two eps
> in the above example are allocated on the same u-frame slot,
> xhci-mtk puts "SSPLIT for EP2" between
> "SSPLIT-start and SSPLIT-end for EP1OUT transaction",
> which is a spec violation. 

Which section in usb2.0 spec?

> Hub will generate bit stuffing errors on the
> full-speed bus.
which platform?

> 
> 
> > 
> > Thanks
> > > 
> > > 
> > > >                         if (tmp > FS_PAYLOAD_MAX)
> > > >                                 return -ESCH_BW_OVERFLOW;
> > > >                 }
> > > > @@ -534,21 +534,18 @@ static void update_sch_tt(struct
> > > > mu3h_sch_ep_info *sch_ep, bool used)
> > > >  {
> > > >         struct mu3h_sch_tt *tt = sch_ep->sch_tt;
> > > >         u32 base, num_esit;
> > > > -       int bw_updated;
> > > >         int i, j;
> > > > 
> > > >         num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
> > > > 
> > > > -       if (used)
> > > > -               bw_updated = sch_ep->bw_cost_per_microframe;
> > > > -       else
> > > > -               bw_updated = -sch_ep->bw_cost_per_microframe;
> > > > -
> > > >         for (i = 0; i < num_esit; i++) {
> > > >                 base = sch_ep->offset + i * sch_ep->esit;
> > > > 
> > > > -               for (j = 0; j < sch_ep->cs_count; j++)
> > > > -                       tt->fs_bus_bw[base + j] += bw_updated;
> > > > +               for (j = 0; j < sch_ep->num_budget_microframes;
> > > > j++)
> > > > +                       if (used)
> > > > +                               tt->fs_bus_bw[base + j] +=
> > > > sch_ep-
> > > > > bw_budget_table[j];
> > > > 
> > > > +                       else
> > > > +                               tt->fs_bus_bw[base + j] -=
> > > > sch_ep-
> > > > > bw_budget_table[j];
> > > > 
> > > >         }
> > > > 
> > > >         if (used)
> > > > --
> > > > 2.18.0
> > > >
Ikjoon Jang Aug. 30, 2021, 3:49 a.m. UTC | #5
On Fri, Aug 27, 2021 at 5:49 PM Chunfeng Yun (云春峰)
<Chunfeng.Yun@mediatek.com> wrote:
>
> On Fri, 2021-08-27 at 17:14 +0800, Ikjoon Jang wrote:
> > On Fri, Aug 27, 2021 at 2:49 PM Chunfeng Yun (云春峰)
> > <Chunfeng.Yun@mediatek.com> wrote:
> > >
> > > On Thu, 2021-08-26 at 19:54 +0800, Ikjoon Jang wrote:
> > > > Hi Chunfeng,
> > > >
> > > > On Thu, Aug 26, 2021 at 10:52 AM Chunfeng Yun <
> > > > chunfeng.yun@mediatek.com> wrote:
> > > > >
> > > > > Use @bw_budget_table[] to update fs bus bandwidth due to
> > > > > not all microframes consume @bw_cost_per_microframe, see
> > > > > setup_sch_info().
> > > > >
> > > > > Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
> > > > > ---
> > > > > v2: new patch, move from another series
> > > > > ---
> > > > >  drivers/usb/host/xhci-mtk-sch.c | 17 +++++++----------
> > > > >  1 file changed, 7 insertions(+), 10 deletions(-)
> > > > >
> > > > > diff --git a/drivers/usb/host/xhci-mtk-sch.c
> > > > > b/drivers/usb/host/xhci-mtk-sch.c
> > > > > index cffcaf4dfa9f..83abd28269ca 100644
> > > > > --- a/drivers/usb/host/xhci-mtk-sch.c
> > > > > +++ b/drivers/usb/host/xhci-mtk-sch.c
> > > > > @@ -458,8 +458,8 @@ static int check_fs_bus_bw(struct
> > > > > mu3h_sch_ep_info *sch_ep, int offset)
> > > > >                  * Compared with hs bus, no matter what ep
> > > > > type,
> > > > >                  * the hub will always delay one uframe to send
> > > > > data
> > > > >                  */
> > > > > -               for (j = 0; j < sch_ep->cs_count; j++) {
> > > > > -                       tmp = tt->fs_bus_bw[base + j] + sch_ep-
> > > > > > bw_cost_per_microframe;
> > > > >
> > > > > +               for (j = 0; j < sch_ep->num_budget_microframes;
> > > > > j++) {
> > > > > +                       tmp = tt->fs_bus_bw[base + j] + sch_ep-
> > > > > > bw_budget_table[j];
> > > >
> > > > I'm worrying about this case with two endpoints,
> > > > * EP1OUT: isochronous, maxpacket=192: bw_budget_table[] = { 188,
> > > > 188,
> > > > 0, ... }
> > > > * EP2IN: interrupt, maxpacket=64: bw_budget_table[] = { 0, 0, 64,
> > > > 64,
> > > > ... }
> > > > (Is this correct bw_budget_table contents for those eps?)
> > >
> > > Yes, ep1out isoc use two uframe, ep2in intr use a extra cs;
> > > >
> > > > I'm not sure if it's okay for those two endpoints to be allocated
> > > > on the same u-frame slot.
> > > > Can you please check if this is okay for xhci-mtk?
> > >
> > > Already test it this afternoon, can transfer data rightly on our
> > > dvt
> > > env.
> > >
> > > > (I feel like I already asked the same questions many times.)
> > >
> > > Yes, as said before, prefer to use bw_budget_table[], if there is
> > > issue, we can fix it by building this table.
> >
> > So do you mean such an allocation shouldn't be a problem by IP
> > design?
> Yes, at least on our dvt platform

Did you check that your side also has a similar allocation
(SSPLIT-all sits between SSPLIT-start ~ -end for another ep)?
My audio headset doesn't work properly with this scheme.

>
> >
> > This patch starts to allow such an allocation (again).
> > But i remember my earlier tests showed that when those two eps
> > in the above example are allocated on the same u-frame slot,
> > xhci-mtk puts "SSPLIT for EP2" between
> > "SSPLIT-start and SSPLIT-end for EP1OUT transaction",
> > which is a spec violation.
>
> Which section in usb2.0 spec?

I think that's just a basic rule - if software wants to send 192 bytes
through a full-speed bus, HC should send OUT/DATA 192 bytes
continuously without inserting any other packets during that 192 bytes.
and usb2 11.14.2 mentions that TT has separated
Start-Split and Complete-Split buffers
but not tracked each transaction per endpoint basis.

>
> > Hub will generate bit stuffing errors on the
> > full-speed bus.
> which platform?

I remember it was mt8173.

And for bit stuffing errors I mentioned in the earlier mail.
when I read the spec again, 11.21 mentions that bit stuffing error
is generated when _a microframe_ should be passed without
corresponding SSPLIT-mid/end. So this is not the case and also
I'm not sure what will happen on the full-speed bus, sorry.
In my case what I can be sure of is that the audio output was
broken with those allotments.

What is the xhci-mtk's policy when there are more than two EPs
marked as the same u-frame offset like in the above example?

>
> >
> >
> > >
> > > Thanks
> > > >
> > > >
> > > > >                         if (tmp > FS_PAYLOAD_MAX)
> > > > >                                 return -ESCH_BW_OVERFLOW;
> > > > >                 }
> > > > > @@ -534,21 +534,18 @@ static void update_sch_tt(struct
> > > > > mu3h_sch_ep_info *sch_ep, bool used)
> > > > >  {
> > > > >         struct mu3h_sch_tt *tt = sch_ep->sch_tt;
> > > > >         u32 base, num_esit;
> > > > > -       int bw_updated;
> > > > >         int i, j;
> > > > >
> > > > >         num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
> > > > >
> > > > > -       if (used)
> > > > > -               bw_updated = sch_ep->bw_cost_per_microframe;
> > > > > -       else
> > > > > -               bw_updated = -sch_ep->bw_cost_per_microframe;
> > > > > -
> > > > >         for (i = 0; i < num_esit; i++) {
> > > > >                 base = sch_ep->offset + i * sch_ep->esit;
> > > > >
> > > > > -               for (j = 0; j < sch_ep->cs_count; j++)
> > > > > -                       tt->fs_bus_bw[base + j] += bw_updated;
> > > > > +               for (j = 0; j < sch_ep->num_budget_microframes;
> > > > > j++)
> > > > > +                       if (used)
> > > > > +                               tt->fs_bus_bw[base + j] +=
> > > > > sch_ep-
> > > > > > bw_budget_table[j];
> > > > >
> > > > > +                       else
> > > > > +                               tt->fs_bus_bw[base + j] -=
> > > > > sch_ep-
> > > > > > bw_budget_table[j];
> > > > >
> > > > >         }
> > > > >
> > > > >         if (used)
> > > > > --
> > > > > 2.18.0
> > > > >
Chunfeng Yun Aug. 31, 2021, 6:50 a.m. UTC | #6
On Mon, 2021-08-30 at 11:49 +0800, Ikjoon Jang wrote:
> On Fri, Aug 27, 2021 at 5:49 PM Chunfeng Yun (云春峰)
> <Chunfeng.Yun@mediatek.com> wrote:
> > 
> > On Fri, 2021-08-27 at 17:14 +0800, Ikjoon Jang wrote:
> > > On Fri, Aug 27, 2021 at 2:49 PM Chunfeng Yun (云春峰)
> > > <Chunfeng.Yun@mediatek.com> wrote:
> > > > 
> > > > On Thu, 2021-08-26 at 19:54 +0800, Ikjoon Jang wrote:
> > > > > Hi Chunfeng,
> > > > > 
> > > > > On Thu, Aug 26, 2021 at 10:52 AM Chunfeng Yun <
> > > > > chunfeng.yun@mediatek.com> wrote:
> > > > > > 
> > > > > > Use @bw_budget_table[] to update fs bus bandwidth due to
> > > > > > not all microframes consume @bw_cost_per_microframe, see
> > > > > > setup_sch_info().
> > > > > > 
> > > > > > Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
> > > > > > ---
> > > > > > v2: new patch, move from another series
> > > > > > ---
> > > > > >  drivers/usb/host/xhci-mtk-sch.c | 17 +++++++----------
> > > > > >  1 file changed, 7 insertions(+), 10 deletions(-)
> > > > > > 
> > > > > > diff --git a/drivers/usb/host/xhci-mtk-sch.c
> > > > > > b/drivers/usb/host/xhci-mtk-sch.c
> > > > > > index cffcaf4dfa9f..83abd28269ca 100644
> > > > > > --- a/drivers/usb/host/xhci-mtk-sch.c
> > > > > > +++ b/drivers/usb/host/xhci-mtk-sch.c
> > > > > > @@ -458,8 +458,8 @@ static int check_fs_bus_bw(struct
> > > > > > mu3h_sch_ep_info *sch_ep, int offset)
> > > > > >                  * Compared with hs bus, no matter what ep
> > > > > > type,
> > > > > >                  * the hub will always delay one uframe to
> > > > > > send
> > > > > > data
> > > > > >                  */
> > > > > > -               for (j = 0; j < sch_ep->cs_count; j++) {
> > > > > > -                       tmp = tt->fs_bus_bw[base + j] +
> > > > > > sch_ep-
> > > > > > > bw_cost_per_microframe;
> > > > > > 
> > > > > > +               for (j = 0; j < sch_ep-
> > > > > > >num_budget_microframes;
> > > > > > j++) {
> > > > > > +                       tmp = tt->fs_bus_bw[base + j] +
> > > > > > sch_ep-
> > > > > > > bw_budget_table[j];
> > > > > 
> > > > > I'm worrying about this case with two endpoints,
> > > > > * EP1OUT: isochronous, maxpacket=192: bw_budget_table[] = {
> > > > > 188,
> > > > > 188,
> > > > > 0, ... }
> > > > > * EP2IN: interrupt, maxpacket=64: bw_budget_table[] = { 0, 0,
> > > > > 64,
> > > > > 64,
> > > > > ... }
> > > > > (Is this correct bw_budget_table contents for those eps?)
> > > > 
> > > > Yes, ep1out isoc use two uframe, ep2in intr use a extra cs;
> > > > > 
> > > > > I'm not sure if it's okay for those two endpoints to be
> > > > > allocated
> > > > > on the same u-frame slot.
> > > > > Can you please check if this is okay for xhci-mtk?
> > > > 
> > > > Already test it this afternoon, can transfer data rightly on
> > > > our
> > > > dvt
> > > > env.
> > > > 
> > > > > (I feel like I already asked the same questions many times.)
> > > > 
> > > > Yes, as said before, prefer to use bw_budget_table[], if there
> > > > is
> > > > issue, we can fix it by building this table.
> > > 
> > > So do you mean such an allocation shouldn't be a problem by IP
> > > design?
> > 
> > Yes, at least on our dvt platform
> 
> Did you check that your side also has a similar allocation
> (SSPLIT-all sits between SSPLIT-start ~ -end for another ep)?
> My audio headset doesn't work properly with this scheme.
> 
> > 
> > > 
> > > This patch starts to allow such an allocation (again).
> > > But i remember my earlier tests showed that when those two eps
> > > in the above example are allocated on the same u-frame slot,
> > > xhci-mtk puts "SSPLIT for EP2" between
> > > "SSPLIT-start and SSPLIT-end for EP1OUT transaction",
> > > which is a spec violation.
> > 
> > Which section in usb2.0 spec?
> 
> I think that's just a basic rule - if software wants to send 192
> bytes
> through a full-speed bus, HC should send OUT/DATA 192 bytes
> continuously without inserting any other packets during that 192
> bytes.
> and usb2 11.14.2 mentions that TT has separated
> Start-Split and Complete-Split buffers
> but not tracked each transaction per endpoint basis.
> 
> > 
> > > Hub will generate bit stuffing errors on the
> > > full-speed bus.
> > 
> > which platform?
> 
> I remember it was mt8173.
Does it happen on mt8192?

> 
> And for bit stuffing errors I mentioned in the earlier mail.
> when I read the spec again, 11.21 mentions that bit stuffing error
> is generated when _a microframe_ should be passed without
> corresponding SSPLIT-mid/end. So this is not the case and also
> I'm not sure what will happen on the full-speed bus, sorry.
> In my case what I can be sure of is that the audio output was
> broken with those allotments.
> 
> What is the xhci-mtk's policy when there are more than two EPs
> marked as the same u-frame offset like in the above example?
Seems no this limitation, an EP doesn't monopolize an u-frame

> 
> > 
> > > 
> > > 
> > > > 
> > > > Thanks
> > > > > 
> > > > > 
> > > > > >                         if (tmp > FS_PAYLOAD_MAX)
> > > > > >                                 return -ESCH_BW_OVERFLOW;
> > > > > >                 }
> > > > > > @@ -534,21 +534,18 @@ static void update_sch_tt(struct
> > > > > > mu3h_sch_ep_info *sch_ep, bool used)
> > > > > >  {
> > > > > >         struct mu3h_sch_tt *tt = sch_ep->sch_tt;
> > > > > >         u32 base, num_esit;
> > > > > > -       int bw_updated;
> > > > > >         int i, j;
> > > > > > 
> > > > > >         num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
> > > > > > 
> > > > > > -       if (used)
> > > > > > -               bw_updated = sch_ep-
> > > > > > >bw_cost_per_microframe;
> > > > > > -       else
> > > > > > -               bw_updated = -sch_ep-
> > > > > > >bw_cost_per_microframe;
> > > > > > -
> > > > > >         for (i = 0; i < num_esit; i++) {
> > > > > >                 base = sch_ep->offset + i * sch_ep->esit;
> > > > > > 
> > > > > > -               for (j = 0; j < sch_ep->cs_count; j++)
> > > > > > -                       tt->fs_bus_bw[base + j] +=
> > > > > > bw_updated;
> > > > > > +               for (j = 0; j < sch_ep-
> > > > > > >num_budget_microframes;
> > > > > > j++)
> > > > > > +                       if (used)
> > > > > > +                               tt->fs_bus_bw[base + j] +=
> > > > > > sch_ep-
> > > > > > > bw_budget_table[j];
> > > > > > 
> > > > > > +                       else
> > > > > > +                               tt->fs_bus_bw[base + j] -=
> > > > > > sch_ep-
> > > > > > > bw_budget_table[j];
> > > > > > 
> > > > > >         }
> > > > > > 
> > > > > >         if (used)
> > > > > > --
> > > > > > 2.18.0
> > > > > >
diff mbox series

Patch

diff --git a/drivers/usb/host/xhci-mtk-sch.c b/drivers/usb/host/xhci-mtk-sch.c
index cffcaf4dfa9f..83abd28269ca 100644
--- a/drivers/usb/host/xhci-mtk-sch.c
+++ b/drivers/usb/host/xhci-mtk-sch.c
@@ -458,8 +458,8 @@  static int check_fs_bus_bw(struct mu3h_sch_ep_info *sch_ep, int offset)
 		 * Compared with hs bus, no matter what ep type,
 		 * the hub will always delay one uframe to send data
 		 */
-		for (j = 0; j < sch_ep->cs_count; j++) {
-			tmp = tt->fs_bus_bw[base + j] + sch_ep->bw_cost_per_microframe;
+		for (j = 0; j < sch_ep->num_budget_microframes; j++) {
+			tmp = tt->fs_bus_bw[base + j] + sch_ep->bw_budget_table[j];
 			if (tmp > FS_PAYLOAD_MAX)
 				return -ESCH_BW_OVERFLOW;
 		}
@@ -534,21 +534,18 @@  static void update_sch_tt(struct mu3h_sch_ep_info *sch_ep, bool used)
 {
 	struct mu3h_sch_tt *tt = sch_ep->sch_tt;
 	u32 base, num_esit;
-	int bw_updated;
 	int i, j;
 
 	num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
 
-	if (used)
-		bw_updated = sch_ep->bw_cost_per_microframe;
-	else
-		bw_updated = -sch_ep->bw_cost_per_microframe;
-
 	for (i = 0; i < num_esit; i++) {
 		base = sch_ep->offset + i * sch_ep->esit;
 
-		for (j = 0; j < sch_ep->cs_count; j++)
-			tt->fs_bus_bw[base + j] += bw_updated;
+		for (j = 0; j < sch_ep->num_budget_microframes; j++)
+			if (used)
+				tt->fs_bus_bw[base + j] += sch_ep->bw_budget_table[j];
+			else
+				tt->fs_bus_bw[base + j] -= sch_ep->bw_budget_table[j];
 	}
 
 	if (used)