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<DC-IRC> <microlinux> @clever___ do you know anything abut the hw media dec capabilities on RPI 5?
<DC-IRC> <clever___> from what ive seen on the forums, it only has h265/hevc decode, and nothing else
<DC-IRC> <microlinux> I only found h265 4h60 decoding capabilities, but h264 was removed entirely
<DC-IRC> <clever___> they have even dropped h264 hw
<DC-IRC> <microlinux> does it have anything else?
<DC-IRC> <clever___> nothing that ive heard of so far
<DC-IRC> <microlinux> bc h265 only looks quite por
<DC-IRC> <microlinux> poor
<DC-IRC> <clever___> even the hw jpeg was removed
<DC-IRC> <clever___> its kind of like the gutted the videocore design, leaving only the 2d/3d and hevc
<DC-IRC> <clever___> its kind of like the gutted the videocore design, leaving only the 2d/3d/vpu and hevc
<DC-IRC> <microlinux> know I know why they basically release no info about that... it looks really bad hw wise.
<DC-IRC> <microlinux> the cpu is amazing
<DC-IRC> <microlinux> but having to do everything on software is the opposite of arm hw...
<DC-IRC> <clever___> they did at least add the arm crypto extensions
<DC-IRC> <microlinux> indeed!
<DC-IRC> <clever___> and the new ISP is now properly driven by linux
<DC-IRC> <clever___> so the ISP could be reused for some things
<DC-IRC> <microlinux> yeah, I heard about threadX being removed
<DC-IRC> <clever___> i'm not sure if threadx was actually removed or not
<DC-IRC> <clever___> need to investigate that
<DC-IRC> <microlinux> but what code is in charge instead, and how open source is it?
<DC-IRC> <clever___> the VPU is still there, and some of the mailbox services
<DC-IRC> <clever___> the original pi4 firmware, went bootcode.bin -> start4.elf -> kernel.img
<DC-IRC> <clever___> and start4.elf managed h264, isp, and a few other things
<DC-IRC> <clever___> the network install changes altered how pi4 works, making it:
<DC-IRC> <clever___> bootcode.bin -> bootmain.elf -> start4.elf -> kernel.img
<DC-IRC> <clever___> with bootmain.elf stored in SPI as well
<DC-IRC> <clever___> the pi5 then just deleted a step
<DC-IRC> <clever___> bootcode.bin -> bootmain.elf -> kernel.img!
<DC-IRC> <clever___> bootmain.elf is now the primary VPU firmware, still held in SPI flash
<DC-IRC> <clever___> `vcgencmd` and the usual firmware stuff appears to still be present, but is talking to `bootmain.elf` instead of `start4.elf`
<DC-IRC> <clever___> i need to fix ghidra, and take a closer look at `bootmain.elf` and see if its threadx or custom
<DC-IRC> <clever___> they have also been making major strides in terms of open source
<DC-IRC> <clever___> linux is now driving the entire camera, 2d, and 3d subsystems, from what i hear
<DC-IRC> <clever___> so the closed source is only doing dram init, basic bootup, and thermal/power throttling, from what ive heard
<DC-IRC> <microlinux> good!
<DC-IRC> <microlinux> i am very disappointed with the hw blocks, but it's very decent for a pi5
<DC-IRC> <clever___> one thing i'm conflicted on, is that putting everything into SPI, is basically one of the plans i had for the open firmware
<DC-IRC> <clever___> but the way they have done it, also makes the chain of trust more solid
<DC-IRC> <clever___> so it may be difficult to run open firmware on the pi5
<DC-IRC> <clever___> on the pi4, the stage-1 file was signed with an hmac-sha1, and i had to dump the bootrom to get the keys and sign custom files
<DC-IRC> <clever___> stage 1.5 is hashed, and stage1 validates the hash
<DC-IRC> <clever___> the expected hash is inside the stage1 binary, so changing the expected hash breaks the stage1 signature
<DC-IRC> <clever___> but stage2 was unsigned, creating a gaping hole in the security, allowing me to dump the keys
<DC-IRC> <clever___> but pi5 deleted stage2 entirely
<DC-IRC> <clever___> stage 1.5 is still hashed
<DC-IRC> <clever___> stage1 unknown
<DC-IRC> <clever___> @microlinux that all make sense?
<DC-IRC> <microlinux> ahaha yeah clever, it makes some.
<DC-IRC> <microlinux> need to go, many thanks for your insights
<DC-IRC> <clever___> without a way to get my foot in the door, there is no way to dump the rom and keys
<DC-IRC> <clever___> until they publish the recovery docs, any attempt to get in thru SPI risk bricking the pi
<DC-IRC> <clever___> but i could try a `recovery.bin` and see what happens....