Fiz um downgrade para o MACOS Catalina e o problema persistiu, o estranho que quando eu fazia o boot com o Clover a memória estava completa e com o opencore somente havia os 4mb.
Como no Clover tudo funcionava, resolvi copiar a seguinte configuração do arquivo config.plist da pasta CLOVER
<key>PciRoot(0x0)/Pci(0x1f,0x3)</key>
<dict>
<key>layout-id</key>
<integer>54</integer>
</dict>
<key>PciRoot(0x0)/Pci(0x2,0x0)</key>
<dict>
<key>AAPL,ig-platform-id</key>
<data>AACbPg==</data>
<key>device-id</key>
<data>mz4AAA==</data>
<key>disable-external-gpu</key>
<data>AQAAAA==</data>
<key>enable-hdmi20</key>
<data>AQAAAA==</data>
<key>enable-lspcon-support</key>
<data>AQAAAA==</data>
<key>framebuffer-con1-busid</key>
<data>AQAAAA==</data>
<key>framebuffer-con1-enable</key>
<data>AQAAAA==</data>
<key>framebuffer-con1-has-lspcon</key>
<data>AQAAAA==</data>
<key>framebuffer-con1-preferred-lspcon-mode</key>
<data>AQAAAA==</data>
<key>framebuffer-con1-type</key>
<data>AAgAAA==</data>
<key>framebuffer-fbmem</key>
<data>AACQAA==</data>
<key>framebuffer-patch-enable</key>
<data>AQAAAA==</data>
<key>framebuffer-stolenmem</key>
<data>AAAwAQ==</data>
</dict>
E colei na pasta OC no arquivo config.plist, substituindo todas as configurações existentes.
O trecho do arquivo ficou da seguinte forma:
<key>DeviceProperties</key>
<dict>
<key>Add</key>
<dict>
<key>PciRoot(0x0)/Pci(0x1f,0x3)</key>
<dict>
<key>layout-id</key>
<integer>54</integer>
</dict>
<key>PciRoot(0x0)/Pci(0x2,0x0)</key>
<dict>
<key>AAPL,ig-platform-id</key>
<data>AACbPg==</data>
<key>device-id</key>
<data>mz4AAA==</data>
<key>disable-external-gpu</key>
<data>AQAAAA==</data>
<key>enable-hdmi20</key>
<data>AQAAAA==</data>
<key>enable-lspcon-support</key>
<data>AQAAAA==</data>
<key>framebuffer-con1-busid</key>
<data>AQAAAA==</data>
<key>framebuffer-con1-enable</key>
<data>AQAAAA==</data>
<key>framebuffer-con1-has-lspcon</key>
<data>AQAAAA==</data>
<key>framebuffer-con1-preferred-lspcon-mode</key>
<data>AQAAAA==</data>
<key>framebuffer-con1-type</key>
<data>AAgAAA==</data>
<key>framebuffer-fbmem</key>
<data>AACQAA==</data>
<key>framebuffer-patch-enable</key>
<data>AQAAAA==</data>
<key>framebuffer-stolenmem</key>
<data>AAAwAQ==</data>
</dict>
</dict>
<key>Delete</key>
<dict/>
</dict>
Para minha surpresa funcionou.
O problema é que agora o brilho está muito baixo e a saída HDMI continua não funcionando.
Alguém pode me ajudar a solucionar esse problema?