Files
android_kernel_samsung_sm86…/target_if/spectral
Shiva Krishna Pittala 0878b6eaf9 qcacmn: Fix FFT bin values for pack mode 0
While copying FFT bins from the target, Spectral Host driver reads
one DWORD (32-bits) at a time and extracts FFT bins out of those DWORDs.
This extraction uses standard bit shift and mask operations as below.

    #define QDF_GET_BITS(_val, _index, _num_bits) \
                    (((_val) >> (_index)) & ((1 << (_num_bits)) - 1))

For a chipset that uses pack mode 0 i.e., packs 1 FFT bin per DWORD,
_num_bits in the above operation will be 32. So, we try to left shift the
integer constant '1' by 32. If the integer constant is represented by
32-bit integer, we could have issues in the result of shift operation.
As per C standard, the result of shifting an operand by a count greater
than or equal to width (in bits) of the operand is undefined.
This is because some platforms could optimize the shift operation by
masking the shift count to 5 bits. That means, the shift actually
performed is 32 & 31, which is 0.

Fix this by using 64-bit integer constant '1' in the above operation.

Change-Id: Ic7fe4de7917f3069d78a2ff29d86009cbf381e3f
CRs-Fixed: 3125158
2022-02-14 12:46:05 -08:00
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