On 7/13/26 08:14, Timur Kristóf wrote: > The old radeon driver has a documented workaround in ci_dpm.c > which claims that Bonaire 0x6658 with old memory controller > firmware is unstable with MCLK DPM, so as a precaution I > disabled MCLK DPM on this ASIC in amdgpu. > > Note that the old MC firmware is not actually used with > amdgpu, but in theory it's possible that the VBIOS sets > up the ASIC with an old MC firmware that is already running > when amdgpu initializes (in which case amdgpu doesn't > load its own firmware). > > What I expected to happen is that the GPU would simply use > its maximum memory clock, and indeed this is what seemed > to happen according to amdgpu_pm_info which reads the > current MCLK value from the SMU. > However, some users reported a huge perf regression
Were those private reports? If not, please consider linking them in the trailers using Link: or Closes: tags, as explained in the patch submission guidelines (and mandated by Linus, see the quotes and links in https://www.kernel.org/doc/html/latest/process/handling-regressions.html#on-the-importance-of-pointing-to-bug-reports-using-link-closes-tags for details). Ciao, Thorsten > and upon a closer look it seems that the GPU seems to > not actually use the highest MCLK value, despite the SMU > reporting that it does. > > Let's not disable MCLK DPM on Bonaire 0x6658 (R7 260X). > > Keep MCLK DPM disabled on R9 M380 in the 2015 iMac > because that still hangs if we enable it. > > Fixes: 9851f29cb06c ("drm/amd/pm/ci: Disable MCLK DPM on problematic CI > ASICs") > Signed-off-by: Timur Kristóf <[email protected]> > --- > drivers/gpu/drm/amd/pm/powerplay/hwmgr/hwmgr.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/hwmgr.c > b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/hwmgr.c > index 1d6e30269d56..4d553be56396 100644 > --- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/hwmgr.c > +++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/hwmgr.c > @@ -106,11 +106,8 @@ int hwmgr_early_init(struct pp_hwmgr *hwmgr) > hwmgr->od_enabled = false; > switch (hwmgr->chip_id) { > case CHIP_BONAIRE: > - /* R9 M380 in iMac 2015: SMU hangs when enabling MCLK > DPM > - * R7 260X cards with old MC ucode: MCLK DPM is unstable > - */ > - if (adev->pdev->subsystem_vendor == 0x106B || > - adev->pdev->device == 0x6658) { > + /* R9 M380 in iMac 2015: SMU hangs when enabling MCLK > DPM */ > + if (adev->pdev->subsystem_vendor == 0x106B) { > dev_info(adev->dev, "disabling MCLK DPM on > quirky ASIC"); > adev->pm.pp_feature &= ~PP_MCLK_DPM_MASK; > hwmgr->feature_mask &= ~PP_MCLK_DPM_MASK;
