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but does it have hdmi 2.1 port?

4k/120/444 will only work on macs that have a hdmi 2.1 port. Adapters won't work.
This is a letdown. I thought thunderbolt 4 supported 4k@120. Wish I got the AORUS 48" oled that has displayport.
 
So i updated to 13.2 on my hackintosh with 6800 XT. I expected hdmi 2.1 ports to give me 4k/120 hz out of the box. No luck. I tried both DP -> HDMI 2.1 and HDMI -> HDMI cables. No 120 Hz at all. Limited to 60Hz only.

The same 13.2 update allows 4k/120 and above for M2 MBP when the reviewers tested it with their TV/Monitors.

So Apple deliberately is not allowing hdmi 2.1 port on AMD 6000 cards which means e-gpus and Mac Pros are out of luck.

This is very bad.
 
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Yep, looks like adapters wont work on older m1s.

if you want 4k/120/444/hdr , only 2 options - m2 mac mini and m2 macbook pro.

I don't think adapters are going to work as we expected.

I believe this is because on older models the signal is going via the DP 1.4 which cannot do 4k/120/444.

But atleast two apple products support hdmi 2.1. which is a good start.

if you want 4k/120/444 , you will have to upgrade to the M2.
My M1 Max does 4k@144Hz no problem over DP1.4. It also wasn’t an issue on older nvidia-GPUs (2080-series) on Windows that didn’t have a physical HDMI 2.1-port. So it’s 100% Apple that’s artificially limiting the older MacBooks.
 
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So i updated to 13.2 on my hackintosh with 6800 XT. I expected hdmi 2.1 ports to give me 4k/120 hz out of the box. No luck. I tried both DP -> HDMI 2.1 and HDMI -> HDMI cables. No 120 Hz at all. Limited to 60Hz only.

The same 13.2 update allows 4k/120 and above for M2 MBP when the reviewers tested it with their TV/Monitors.

So Apple deliberately is not allowing hdmi 2.1 port on AMD 6000 cards which means e-gpus and Mac Pros are out of luck.

This is very bad.
Honestly speaking this isn't "very bad," it's flat out unacceptable. Apple sells Mac Pros with RDNA 2 GPUs that we KNOW have hardware support for HDMI 2.1.
There is literally no good reason this shouldn't work, particularly on those GPUs, but also via Thunderbolt/USB4 adaptors.

My hope is that this is just Apple's initial implementation of HDMI 2.1, and that support will be enabled for other Macs soon.
Heck, I wouldn't be surprised if someone in the hackintosh community is able to get it working by mucking around with kexts but hopefully it won't come to that.

I would encourage everyone to impress upon Apple (via submitting bug reports, feature requests, etc) the importance of properly supporting HDMI 2.1 across the entire lineup.
 
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Well I just updated my 2018 Mac Mini to 13.2 from Big Sur.
Using the Cable Matters 48Gbps USB C to HDMI 2.1 Adapter and I'm still at 60hz on my 42" LG C2 OLED.
But under 13.2 I can now enable HDR when using the adapter.

Interestingly after updating, when I press the green button on my remote 7 times, using the built in HDMI port it says YCBCR420 10b TM.
Using the adapter it says YCBCR444 10b 4L6.
 
Well I just updated my 2018 Mac Mini to 13.2 from Big Sur.
Using the Cable Matters 48Gbps USB C to HDMI 2.1 Adapter and I'm still at 60hz on my 42" LG C2 OLED.
But under 13.2 I can now enable HDR when using the adapter.

Interestingly after updating, when I press the green button on my remote 7 times, using the built in HDMI port it says YCBCR420 10b TM.
Using the adapter it says YCBCR444 10b 4L6.
Same with my hackintosh with 6800 XT.

They are deliberately limiting the hdmi 2.1 bandwidth on non M2 mac minis and MBPs.

I was expecting to get 4k/120/444/10b/HDR with the 13.2 update. But not happening.
 
Same with my hackintosh with 6800 XT.

They are deliberately limiting the hdmi 2.1 bandwidth on non M2 mac minis and MBPs.

I was expecting to get 4k/120/444/10b/HDR with the 13.2 update. But not happening.

What if you try and run the new M2 Mini - system model/definition on your hack? Just curious if it will even boot, since its not an “M” chip.
 
if Apple wanted to make hdmi 2.1 feature available to M1 and Mac pro users , they would have introduced usb-c to hdmi 2.1 dongles by now. But they didn't so...
 
if Apple wanted to make hdmi 2.1 feature available to M1 and Mac pro users , they would have introduced usb-c to hdmi 2.1 dongles by now. But they didn't so...

I was referring to the system definition change only. I know Apple has been software locked HDMI end-point since forever.
 
Can Confirm M1 Max MacBook Pro 16 Inch with USB 4 > HDMI 2.1 does only getting 60hz !! Its absolutely a blame what apple did...
 
if Apple wanted to make hdmi 2.1 feature available to M1 and Mac pro users , they would have introduced usb-c to hdmi 2.1 dongles by now. But they didn't so...
We don't know yet if the new M2 Max/Pro Macs have a fully HDMI 2.1 port or if it uses a DisplayPort 1.4 to HDMI 2.1 adapter. Every recent HDMI 2.0 Mac uses a DisplayPort 1.4 to HDMI 2.0b adapter.
https://www.ifixit.com/News/54122/macbook-pro-2021-teardown
Maybe there's something new in the latest macOS display overrides folder. I know Ventura added the possibility of having overrides for dongles instead of displays but I haven't looked into how that gets used and there were no dongle overrides last time I looked in an older version of Ventura.
 
M1 Macs with built-in DP to HDMI chips use this chip to convert the DisplayPort signal to HDMI 2.0

Screenshot_2023-01-24_at_15.22.35.png


If any of you have a hands on then new M2 macs with HDMI (both the M2 baseline mini and the M2 Pro class machines as they must have differing hardwares), please let me know.

It would be educational to see what's inside (I mean via the IO registry, not by opening up the Mac :)).
 
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But I have an M2. I am guessing you mean only the pro and the max m2?
Yes, until Apple stops being greedy or someone finds a way to hack it, you're stuck ponying up for the M2 pro version of the mini for the cheapest Mac that'll do 4K120. It's definitely an upsell as if you're able to get 4k120 with a displayport monitor all day long on M1 Macs or the M2 Air which means the dongle should work. Sad, as I was about to buy the cheaper M2 mini to use as a HTPC before finding this out.
 
My M2 baseline mini is scheduled to arrive tomorrow. If nobody else does it first, I will.
Nice + congrats for the purchase! If you have a HDMI display and willing to try out, can you let me know if BetterDisplay can control the display via DDC over the HDMI port using the latest beta version: v1.3.12-beta

If you open the app, go to Settings (gear icon)/Displays and under the HDMI display you look at `Show display information` and see `Uses built-in HDMI port` then it means the M2 baseline mini is using the same HDMI 2.0 chip as the M1 mini. It would be a valuable information to me (and the community). Thanks for your time! :)

Screenshot 2023-01-24 at 15.40.13.png
 
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Clarification: if you want to check what HDMI converter chip is in your M1/M2 mac, simply open Terminal and enter the following command. It should (probably) give the right result on M2 as well:

Code:
ioreg -r -t -n dp2hdmi-gpio

The ouptut should be something like this:

Code:
+-o Root  <class IORegistryEntry, id 0x100000100, retain 36>
  +-o J314sAP  <class IOPlatformExpertDevice, id 0x10000024b, registered, matched, active, busy 0 (18252 ms), retain 42>
    +-o AppleARMPE  <class AppleARMPE, id 0x100000250, registered, matched, active, busy 0 (10234 ms), retain 46>
      +-o arm-io  <class IOPlatformDevice, id 0x100000124, registered, matched, active, busy 0 (10209 ms), retain 153>
        +-o AppleT600xIO  <class AppleT600xIO, id 0x10000028d, registered, matched, active, busy 0 (10187 ms), retain 150>
          +-o dp2hdmi-gpio  <class AppleARMIODevice, id 0x1000001c8, registered, matched, active, busy 0 (423 ms), retain 9>
            | {
            |   "function-reset" = <b200000034574b703830506700000100>
            |   "function-force-dpfu-open-drain" = <860000004f4950470c00000000000100>
            |   "function-force-dpfu" = <860000004f4950470c00000001000000>
            |   "function-dp2hdmi_pwr_en" = <b200000034574b703630506700000000>
            |   "function-hdmi_pwr_en" = <b200000034574b703731506700008000>
            |   "device_type" = <"dp2hdmi-gpio">
            |   "name" = <"dp2hdmi-gpio">
            |   "AAPL,phandle" = <cb000000>
            | }
            |
            +-o AppleMCDP29XXGPIO  <class AppleMCDP29XXGPIO, id 0x1000002ea, registered, matched, active, busy 0 (0 ms), retain 5>

The last line is important, the chip's name in M1 is MCDP29XX (MCDP2900) - https://www.alldatasheet.com/datasheet-pdf/pdf/1150671/ETC2/MCDP2900.html

M2 Pro/Max should have something different there (if the internal layout is similar and Apple still uses some kind of DP2HDMI converter chip).
 
Clarification: if you want to check what HDMI converter chip is in your M1/M2 mac, simply open Terminal and enter the following command. It should (probably) give the right result on M2 as well:
Thanks for the easy to follow instructions. When it arrives, I'll get on that and get back to you.
 
The last line is important, the chip's name in M1 is MCDP29XX (MCDP2900) - https://www.alldatasheet.com/datasheet-pdf/pdf/1150671/ETC2/MCDP2900.html

M2 Pro/Max should have something different there (if the internal layout is similar and Apple still uses some kind of DP2HDMI converter chip).
Even though it's a DisplayPort to HDMI adapter, GPIO seems to imply that Apple has a sideband connection for doing power management instead of using DisplayPort aux channel or DDC/CI.

Speaking of DDC/CI and DisplayPort, have you looked for an API on Apple Silicon Macs like the one used for DDC/CI that can be used to get DisplayPort DPCD? Then AllRez could use that API to get info from the adapter or the display.
 
Even though it's a DisplayPort to HDMI adapter, GPIO seems to imply that Apple has a sideband connection for doing power management instead of using DisplayPort aux channel or DDC/CI.

Speaking of DDC/CI and DisplayPort, have you looked for an API on Apple Silicon Macs like the one used for DDC/CI that can be used to get DisplayPort DPCD? Then AllRez could use that API to get info from the adapter or the display.

Hi @joevt

There seem to be some device level stuff that seems to be related to reading DPCD data, similar to I2C, I suppose these could be used, but did not go into that honestly so it needs more digging. Btw, great job with AllRez, I did find valuable treasures in it, thanks for all you do for the community! :)

Screenshot 2023-01-24 at 16.27.46.png
 
Clarification: if you want to check what HDMI converter chip is in your M1/M2 mac, simply open Terminal and enter the following command. It should (probably) give the right result on M2 as well:

Code:
ioreg -r -t -n dp2hdmi-gpio

The ouptut should be something like this:

Code:
+-o Root  <class IORegistryEntry, id 0x100000100, retain 36>
  +-o J314sAP  <class IOPlatformExpertDevice, id 0x10000024b, registered, matched, active, busy 0 (18252 ms), retain 42>
    +-o AppleARMPE  <class AppleARMPE, id 0x100000250, registered, matched, active, busy 0 (10234 ms), retain 46>
      +-o arm-io  <class IOPlatformDevice, id 0x100000124, registered, matched, active, busy 0 (10209 ms), retain 153>
        +-o AppleT600xIO  <class AppleT600xIO, id 0x10000028d, registered, matched, active, busy 0 (10187 ms), retain 150>
          +-o dp2hdmi-gpio  <class AppleARMIODevice, id 0x1000001c8, registered, matched, active, busy 0 (423 ms), retain 9>
            | {
            |   "function-reset" = <b200000034574b703830506700000100>
            |   "function-force-dpfu-open-drain" = <860000004f4950470c00000000000100>
            |   "function-force-dpfu" = <860000004f4950470c00000001000000>
            |   "function-dp2hdmi_pwr_en" = <b200000034574b703630506700000000>
            |   "function-hdmi_pwr_en" = <b200000034574b703731506700008000>
            |   "device_type" = <"dp2hdmi-gpio">
            |   "name" = <"dp2hdmi-gpio">
            |   "AAPL,phandle" = <cb000000>
            | }
            |
            +-o AppleMCDP29XXGPIO  <class AppleMCDP29XXGPIO, id 0x1000002ea, registered, matched, active, busy 0 (0 ms), retain 5>

The last line is important, the chip's name in M1 is MCDP29XX (MCDP2900) - https://www.alldatasheet.com/datasheet-pdf/pdf/1150671/ETC2/MCDP2900.html

M2 Pro/Max should have something different there (if the internal layout is similar and Apple still uses some kind of DP2HDMI converter chip).

This is what i have been saying all along and i suspected . Apple is using DP1.4 to HDMI which does not have enough bandwidth for 4k/120/444/10b/HDR.

At best, it can do 4k/60/444/10b/HDR.

The worst part is even AMD 6000 Series hdmi 2.1 ports are limited. Why? because the W6000 Series used in the Intel Mac Pro uses only hdmi 2.0 ports and limited to 4k/60.

Hence apple will allow 4k/120hz/444/10bit/HDR only if the hardware allows.

So i don't see how we can ever achieve hdmi 2.1 bandwidth. The only way to get hdmi 2.1 working is to get the new M2 mac mini or MBP.

Also hackintosh is dying. so i doubt anyone will put in the effort to make hdmi 2.1 work on the 6000 series even if its possible.

But finally, atleast apple put in the hdmi 2.1 . Only took them like 2 years. LOL. Most apple devices going forward will support hdmi 2.1.
 
@zamzam1235 - this stuff is relevant only for the built-in HDMI port. An external DP-HDMI 2.1 dongle should use DP Alt Mode over USB-C and the dongle does the conversion to HDMI 2.1, so there is no real reason why it can't do 4K@120Hz except for the fact that for whatever reason the DCP (display coprocessor) firmware does not seem to want that. It seems to be a limitation that might come from a simple oversight and for the new Macs with the built-in HDMI 2.1 port Apple might have changed stuff specifically for the new built-in converter chip without touching anything else on a not-broken-don't-fix-it note.
 
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