drm/nouveau/pmu/fuc: don't use movw directly anymore
Fixes failure to compile with recent envyas as a result of the 'movw' alias being removed for v5. A bit of history: v3 only has a 16-bit sign-extended immediate mov op. In order to set the high bits, there's a separate 'sethi' op. envyas validates that the value passed to mov(imm) is between -0x8000 and 0x7fff. In order to simplify macros that load both the low and high word, a 'movw' alias was added which takes an unsigned 16-bit immediate. However the actual hardware op still sign extends. v5 has a full 32-bit immediate mov op. The v3 16-bit immediate mov op is gone (loads 0 into the dst reg). However due to a bug in envyas, the movw alias still existed, and selected the no-longer-present v3 16-bit immediate mov op. As a result usage of movw on v5 is the same as mov with a 0x0 argument. The proper fix throughout is to only ever use the 'movw' alias in combination with 'sethi'. Anything else should get the sign-extended validation to ensure that the intended value ends up in the destination register. Changes in fuc3 binaries is the result of a different encoding being selected for a mov with an 8-bit value. v2: added commit message written by Ilia, thanks for that! v3: messed up rebasing, now it should apply Signed-off-by: Karol Herbst <kherbst@redhat.com> Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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