While analyzing the drivers/staging/rtl8723bs/hal/rtl8723b_hal_init.c driver, I noticed the following code:

rtw_write16(padapter, REG_TBTT_PROHIBIT, 0x6404);

There is also a nearby TODO comment:

/* TODO: Remove these magic number */
rtw_write16(padapter, REG_TBTT_PROHIBIT, 0x6404);

At first I assumed this was simply a magic-number cleanup issue, but after tracing the surrounding code and register definitions, the value seems to carry more hardware-specific meaning than I initially expected.

What I found
Near the REG_TBTT_PROHIBIT definition, I found the following comments:

// [3:0] : TBTT prohibit setup in unit of 32us
// [19:8] : TBTT prohibit hold in unit of 32us

#define REG_TBTT_PROHIBIT 0x0540

Based on this, I interpreted 0x6404 as:

setup field = 0x04
hold field = 0x64

And my understanding is that after write16():

the lower byte maps to 0x540
the upper byte maps to 0x541

There are also nearby timing-related register writes such as:

rtw_write8(padapter, REG_ATIMWND, 0x0a); /* 10ms */
rtw_write16(padapter, REG_TSFTR_SYN_OFFSET, 0x7fff);

which made me think that 0x6404 is likely a hardware timing/tuning value related to beacon/TBTT handling.

I also checked upstream drivers and found the exact same value still present in rtl8xxxu:

rtl8xxxu_write16(priv, REG_TBTT_PROHIBIT, 0x6404);

Current concern
At this point, my impression is that:

the value itself appears meaningful as a hardware timing parameter,
it could be rewritten using symbolic bitfield macros,
but since the same raw value has remained in upstream drivers for years, I am unsure whether such a cleanup would actually be considered valuable.

For example, I was considering something like:

#define TBTT_SETUP_TIME(_v) (((_v) & 0xf) << 0 )
#define TBTT_HOLD_TIME(_v) (((_v) & 0xff) << 8 )

/* setup = 0x04, hold = 0x64 */
TBTT_SETUP_TIME(0x04) | TBTT_HOLD_TIME(0x64)

However, I am not sure whether this would meaningfully improve readability/maintainability, or simply make a hardware tuning constant more verbose.

Questions

Would maintainers generally consider this kind of change a worthwhile cleanup patch?
In cases like this, where the value appears to represent a hardware timing/tuning parameter, is it usually preferred to keep the raw constant?
If a staging TODO remains for many years while the same value also exists upstream, how should that usually be interpreted?

I would appreciate any advice regarding both the analysis itself and whether this kind of patch is worth pursuing.