Applied. Thanks!
On Mon, Jul 13, 2026 at 3:30 AM <[email protected]> wrote: > > From: yanglinlin <[email protected]> > > When compiling the AMDGPU display driver for 32-bit architectures, > the linker reports undefined reference to `__udivdi3` in functions > get_dp_dto_frequency_100hz() and dcn401_get_dp_dto_frequency_100hz(). > > This is because the code uses 64-bit division (/) on 32-bit systems, > which GCC cannot handle directly and instead tries to call the missing > __udivdi3 helper function. > > Replace the raw division with div_u64(), the kernel's standard 64-bit > division helper, to avoid the link error. > > Signed-off-by: Linlin Yang <[email protected]> > Reported-by: k2ci <[email protected]> > > --- > v1 -> v2: > Adjust overflow‑check condition: change INT_MAX to UINT_MAX and add 100ULL > suffix, > also reorganize calculation order to avoid potential integer overflow > > drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c | 11 +++++------ > 1 file changed, 5 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c > b/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c > index 7c293917e6fd..ecb8493ec523 100644 > --- a/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c > +++ b/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c > @@ -1229,9 +1229,9 @@ static bool get_dp_dto_frequency_100hz( > */ > modulo_hz = REG_READ(MODULO[inst]); > if (modulo_hz) { > - temp = div_u64((uint64_t)clock_hz * > dp_dto_ref_khz * 10, modulo_hz); > - ASSERT(temp / 100 <= 0xFFFFFFFFUL); > - *pixel_clk_100hz = (unsigned int)(temp / 100); > + temp = clock_hz * dp_dto_ref_khz * 10; > + ASSERT(temp <= UINT_MAX * modulo_hz * 100ULL); > + *pixel_clk_100hz = div_u64(temp, modulo_hz * > 100); > } else > *pixel_clk_100hz = 0; > } else { > @@ -1285,13 +1285,12 @@ static bool dcn401_get_dp_dto_frequency_100hz(const > struct clock_source *clock_s > * - target pix_clk_hz = (DPDTO INTEGER * DPDTO MODULO + > DPDTO PHASE) > */ > temp = (unsigned long long)dp_dto_integer * modulo_hz + > phase_hz; > - > - if (temp / 100 > 0xFFFFFFFFUL) { > + if (temp > (UINT_MAX * 100ULL)) { > /* pixel rate 100hz should never be this high, if it > is, throw an assert and return 0 */ > BREAK_TO_DEBUGGER(); > *pixel_clk_100hz = 0; > } else { > - *pixel_clk_100hz = (unsigned int)(temp / 100); > + *pixel_clk_100hz = div_u64(temp, 100); > } > > return true; > -- > 2.25.1 >
