| Message ID | 20200915180509.2661572-1-dwlsalmeida@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | media: vidtv: fix build on 32bit architectures | expand |
On 9/15/20 11:05 AM, Daniel W. S. Almeida wrote: > From: Daniel W. S. Almeida <dwlsalmeida@gmail.com> > > Fix the following error for builds on 32bit architectures: > > ERROR: modpost: "__udivdi3" > [drivers/media/test-drivers/vidtv/dvb-vidtv-bridge.ko] undefined! > > Which is due to 64bit divisions that did not go through the helpers > in linux/math64.h > > As vidtv_mux_check_mux_rate was not operational in its current form, > drop the entire function while it is not fixed properly. > > For now, call vidtv_mux_pad_with_nulls with a constant number of packets > to avoid warnings due to unused functions when building this driver. > > Fixes: f90cf6079bf67988 ("media: vidtv: add a bridge driver") > Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com> > --- > drivers/media/test-drivers/vidtv/vidtv_mux.c | 34 +------------------ > .../media/test-drivers/vidtv/vidtv_s302m.c | 4 +-- > 2 files changed, 3 insertions(+), 35 deletions(-) > Works for me. Thanks. Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Em Tue, 15 Sep 2020 15:05:09 -0300 "Daniel W. S. Almeida" <dwlsalmeida@gmail.com> escreveu: > From: Daniel W. S. Almeida <dwlsalmeida@gmail.com> > > Fix the following error for builds on 32bit architectures: > > ERROR: modpost: "__udivdi3" > [drivers/media/test-drivers/vidtv/dvb-vidtv-bridge.ko] undefined! > > Which is due to 64bit divisions that did not go through the helpers > in linux/math64.h > > As vidtv_mux_check_mux_rate was not operational in its current form, > drop the entire function while it is not fixed properly. > > For now, call vidtv_mux_pad_with_nulls with a constant number of packets > to avoid warnings due to unused functions when building this driver. > > Fixes: f90cf6079bf67988 ("media: vidtv: add a bridge driver") > Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com> > --- > drivers/media/test-drivers/vidtv/vidtv_mux.c | 34 +------------------ > .../media/test-drivers/vidtv/vidtv_s302m.c | 4 +-- > 2 files changed, 3 insertions(+), 35 deletions(-) > > diff --git a/drivers/media/test-drivers/vidtv/vidtv_mux.c b/drivers/media/test-drivers/vidtv/vidtv_mux.c > index 5d1a275d504b..6e402a880fdc 100644 > --- a/drivers/media/test-drivers/vidtv/vidtv_mux.c > +++ b/drivers/media/test-drivers/vidtv/vidtv_mux.c > @@ -336,38 +336,6 @@ static u32 vidtv_mux_pad_with_nulls(struct vidtv_mux *m, u32 npkts) > return nbytes; > } > > -static u32 vidtv_mux_check_mux_rate(struct vidtv_mux *m) > -{ > - /* > - * attempt to maintain a constant mux rate, padding with null packets > - * if needed > - */ > - > - u32 nbytes = 0; /* the number of bytes written by this function */ > - > - u64 nbytes_expected; /* the number of bytes we should have written */ > - u64 nbytes_streamed; /* the number of bytes we actually wrote */ > - u32 num_null_pkts; /* number of null packets to bridge the gap */ > - > - u64 elapsed_time_msecs = jiffies_to_usecs(m->timing.current_jiffies - > - m->timing.past_jiffies); > - > - elapsed_time_msecs = min(elapsed_time_msecs, (u64)VIDTV_MAX_SLEEP_USECS / 1000); > - nbytes_expected = div64_u64(m->mux_rate_kbytes_sec * 1000, MSEC_PER_SEC); > - nbytes_expected *= elapsed_time_msecs; > - > - nbytes_streamed = m->mux_buf_offset; > - > - if (nbytes_streamed < nbytes_expected) { > - /* can't write half a packet: roundup to a 188 multiple */ > - nbytes_expected = roundup(nbytes_expected - nbytes_streamed, TS_PACKET_LEN); > - num_null_pkts = nbytes_expected / TS_PACKET_LEN; > - nbytes += vidtv_mux_pad_with_nulls(m, num_null_pkts); > - } > - > - return nbytes; > -} > - > static void vidtv_mux_clear(struct vidtv_mux *m) > { > /* clear the packets currently in the mux */ > @@ -397,7 +365,7 @@ static void vidtv_mux_tick(struct work_struct *work) > nbytes += vidtv_mux_push_si(m); > > nbytes += vidtv_mux_poll_encoders(m); > - nbytes += vidtv_mux_check_mux_rate(m); > + nbytes += vidtv_mux_pad_with_nulls(m, 256); > > npkts = nbytes / TS_PACKET_LEN; > > diff --git a/drivers/media/test-drivers/vidtv/vidtv_s302m.c b/drivers/media/test-drivers/vidtv/vidtv_s302m.c > index f8049cdf564a..e3290facf57b 100644 > --- a/drivers/media/test-drivers/vidtv/vidtv_s302m.c > +++ b/drivers/media/test-drivers/vidtv/vidtv_s302m.c > @@ -285,12 +285,12 @@ static void vidtv_s302m_compute_pts(struct vidtv_encoder *e) > { > u64 count = e->sample_count; > struct vidtv_access_unit *au = e->access_units; > + u32 duration = CLOCK_UNIT_90KHZ / e->sampling_rate_hz; > > while (au) { > count += au->num_samples; > > - au->pts = count * > - CLOCK_UNIT_90KHZ / e->sampling_rate_hz; > + au->pts = count * duration; That doesn't seem to be the right thing to do here. Assuming that sampling rate is 48 kHz, you'll have duration = 1.875, which would be rounded to 1. In other words, the above is identical to: au->pts = count Now, I don't know from where that CLOCK_UNIT_90KHZ came from. If such constant is not needed anymore, just drop it. If, on the other hand, this is required by the specs, then you may need to do a 64 bits division, e. g. using div64_u64() or do_div(). Thanks, Mauro
Hi Mauro, Daniel, On Wed, Sep 16, 2020 at 8:40 AM Mauro Carvalho Chehab <mchehab@kernel.org> wrote: > Em Tue, 15 Sep 2020 15:05:09 -0300 > "Daniel W. S. Almeida" <dwlsalmeida@gmail.com> escreveu: > > From: Daniel W. S. Almeida <dwlsalmeida@gmail.com> > > > > Fix the following error for builds on 32bit architectures: > > > > ERROR: modpost: "__udivdi3" > > [drivers/media/test-drivers/vidtv/dvb-vidtv-bridge.ko] undefined! > > > > Which is due to 64bit divisions that did not go through the helpers > > in linux/math64.h > > > > As vidtv_mux_check_mux_rate was not operational in its current form, > > drop the entire function while it is not fixed properly. > > > > For now, call vidtv_mux_pad_with_nulls with a constant number of packets > > to avoid warnings due to unused functions when building this driver. > > > > Fixes: f90cf6079bf67988 ("media: vidtv: add a bridge driver") > > Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # build-tested > > --- a/drivers/media/test-drivers/vidtv/vidtv_s302m.c > > +++ b/drivers/media/test-drivers/vidtv/vidtv_s302m.c > > @@ -285,12 +285,12 @@ static void vidtv_s302m_compute_pts(struct vidtv_encoder *e) > > { > > u64 count = e->sample_count; > > struct vidtv_access_unit *au = e->access_units; > > + u32 duration = CLOCK_UNIT_90KHZ / e->sampling_rate_hz; > > > > while (au) { > > count += au->num_samples; > > > > - au->pts = count * > > - CLOCK_UNIT_90KHZ / e->sampling_rate_hz; > > + au->pts = count * duration; > > That doesn't seem to be the right thing to do here. > > Assuming that sampling rate is 48 kHz, you'll > have duration = 1.875, which would be rounded to 1. > > In other words, the above is identical to: > > au->pts = count > > Now, I don't know from where that CLOCK_UNIT_90KHZ came from. > > If such constant is not needed anymore, just drop it. > > If, on the other hand, this is required by the specs, then > you may need to do a 64 bits division, e. g. using > div64_u64() or do_div(). As vidtv_encoder.sampling_rate_hz is u32, there's fortunately no need to use div64_u64() (64-by-64), so div_u64() (64-by-32) is fine. Gr{oetje,eeting}s, Geert
Hi Mauro, Geert, > That doesn't seem to be the right thing to do here. > > Assuming that sampling rate is 48 kHz, you'll > have duration = 1.875, which would be rounded to 1. > > In other words, the above is identical to: > > au->pts = count > > Now, I don't know from where that CLOCK_UNIT_90KHZ came from. > Mauro, here's my current understanding: The values for PTS have to be defined in terms of a 90khz clock. So for 30fps video, the values for PTS per frame would be: frame_num/30 * 90000 so 0, 3000, 6000, 9000...etc The same math is being used here for audio, but instead we have the total audio sample count and a 48000 samples/sec I did miss this rounding error though, I'm sorry.
diff --git a/drivers/media/test-drivers/vidtv/vidtv_mux.c b/drivers/media/test-drivers/vidtv/vidtv_mux.c index 5d1a275d504b..6e402a880fdc 100644 --- a/drivers/media/test-drivers/vidtv/vidtv_mux.c +++ b/drivers/media/test-drivers/vidtv/vidtv_mux.c @@ -336,38 +336,6 @@ static u32 vidtv_mux_pad_with_nulls(struct vidtv_mux *m, u32 npkts) return nbytes; } -static u32 vidtv_mux_check_mux_rate(struct vidtv_mux *m) -{ - /* - * attempt to maintain a constant mux rate, padding with null packets - * if needed - */ - - u32 nbytes = 0; /* the number of bytes written by this function */ - - u64 nbytes_expected; /* the number of bytes we should have written */ - u64 nbytes_streamed; /* the number of bytes we actually wrote */ - u32 num_null_pkts; /* number of null packets to bridge the gap */ - - u64 elapsed_time_msecs = jiffies_to_usecs(m->timing.current_jiffies - - m->timing.past_jiffies); - - elapsed_time_msecs = min(elapsed_time_msecs, (u64)VIDTV_MAX_SLEEP_USECS / 1000); - nbytes_expected = div64_u64(m->mux_rate_kbytes_sec * 1000, MSEC_PER_SEC); - nbytes_expected *= elapsed_time_msecs; - - nbytes_streamed = m->mux_buf_offset; - - if (nbytes_streamed < nbytes_expected) { - /* can't write half a packet: roundup to a 188 multiple */ - nbytes_expected = roundup(nbytes_expected - nbytes_streamed, TS_PACKET_LEN); - num_null_pkts = nbytes_expected / TS_PACKET_LEN; - nbytes += vidtv_mux_pad_with_nulls(m, num_null_pkts); - } - - return nbytes; -} - static void vidtv_mux_clear(struct vidtv_mux *m) { /* clear the packets currently in the mux */ @@ -397,7 +365,7 @@ static void vidtv_mux_tick(struct work_struct *work) nbytes += vidtv_mux_push_si(m); nbytes += vidtv_mux_poll_encoders(m); - nbytes += vidtv_mux_check_mux_rate(m); + nbytes += vidtv_mux_pad_with_nulls(m, 256); npkts = nbytes / TS_PACKET_LEN; diff --git a/drivers/media/test-drivers/vidtv/vidtv_s302m.c b/drivers/media/test-drivers/vidtv/vidtv_s302m.c index f8049cdf564a..e3290facf57b 100644 --- a/drivers/media/test-drivers/vidtv/vidtv_s302m.c +++ b/drivers/media/test-drivers/vidtv/vidtv_s302m.c @@ -285,12 +285,12 @@ static void vidtv_s302m_compute_pts(struct vidtv_encoder *e) { u64 count = e->sample_count; struct vidtv_access_unit *au = e->access_units; + u32 duration = CLOCK_UNIT_90KHZ / e->sampling_rate_hz; while (au) { count += au->num_samples; - au->pts = count * - CLOCK_UNIT_90KHZ / e->sampling_rate_hz; + au->pts = count * duration; au = au->next; }