GM: Set new longitudinal scaling

[nworb-cire]

Description

See commaai/opendbc#951 for a description of the issue. See commaai/panda#1905, commaai/opendbc#1025 for submodule PRs.

Trivial changes: scaled all values according to the formula f(x) = x + (4096*5) - 22534 which is the new scaling defined in the DBC file.
Nontrivial change: using the above formula, f(ZERO_GAS) == -6. I figured that since this is quite close to 0, it is likely that our previous value of 2048 was a close but incorrect guess at the true zero value. I removed the reference to ZERO_GAS and used 0 instead.

Verification

Marking WIP to validate with the segments dataset as suggested by @sshane

[github-actions]

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[github-actions]

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[nworb-cire]

I have validated these changes on the commaCarSegments dataset, see here. I was a bit unsure what exactly to be looking for, but in my tests nothing looks awry. I was unable to validate a few of the platforms since they have no segments with valid carParams.

[sshane]

@Verylukyguy can you drive on this? I'd like to see just a few routes considering the zero gas is just very slightly different (previous value was -6 in new scale). And a camera-ACC user as well. Then we can merge

[sshane]

for future reference, this is the conversion:

((2048 << 3) | (1 << 15) | (1 << 17)) * 0.125 - 22534

[morrislee]

dc7716b32bf25574/00000000--b86195eae6/0
dc7716b32bf25574/00000001--a72cadb253/0
dc7716b32bf25574/00000002--df117bd704/0

[morrislee]

route with this branch and stock ACC
dc7716b32bf25574/00000004--b140f4714a/0

[Verylukyguy]

@Verylukyguy can you drive on this? I'd like to see just a few routes considering the zero gas is just very slightly different (previous value was -6 in new scale). And a camera-ACC user as well. Then we can merge

I am loading it now and I will test after work!

[Verylukyguy]

2018 GMC Acadia:
df51b2195de66a9b/00000001--797163b3ba/0
df51b2195de66a9b/00000002--af4d93bcfb/0
df51b2195de66a9b/00000004--64c04ece5b/0

[morrislee]

what else do we need to have this merged? POC version currently in FrogPilot with the corrected limit (which need this PR first) makes OP Long very usable

[sshane]

We've moved the car interfacing code to our opendbc repository, which is now the new home for car ports and fingerprints. Please re-open your pull request against opendbc at your convenience by using this command below. This will transform all changes under selfdrive/car/ to opendbc_repo/opendbc/car/. Make sure you have initialized submodules beforehand and have checked out the latest opendbc commit.

PR_NUMBER=33045
curl -L https://github.com/commaai/openpilot/pull/$PR_NUMBER.patch | sed -e 's/selfdrive\/car/opendbc_repo\/opendbc\/car/g' | git apply -v --reject

Simply replace the PR number with your own. Once done, add the files, fix any conflicts, and open a new PR. Alternatively, you may start a new PR from scratch if that is easier for you.