No display on a computer with AMD 6250 graphics

[mounty]

Fresh installation of Haiku, built in a Linux host, from git master 8341933096ea21251fd26a216168f8b0beff7781 (Fri Feb 8 00:17:07 2019). Haiku boots and displays the list of seven startup icons but later (presumably when the generic video driver is replaced by the hardware-specific driver), the screen goes blank.

lspci output is:

00:00.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 14h Processor Root Complex
00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Wrestler [Radeon HD 6250]
00:01.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Wrestler HDMI Audio
00:11.0 SATA controller: Advanced Micro Devices, Inc. [AMD/ATI] SB7x0/SB8x0/SB9x0 SATA Controller [AHCI mode]
00:12.0 USB controller: Advanced Micro Devices, Inc. [AMD/ATI] SB7x0/SB8x0/SB9x0 USB OHCI0 Controller
00:12.2 USB controller: Advanced Micro Devices, Inc. [AMD/ATI] SB7x0/SB8x0/SB9x0 USB EHCI Controller
00:13.0 USB controller: Advanced Micro Devices, Inc. [AMD/ATI] SB7x0/SB8x0/SB9x0 USB OHCI0 Controller
00:13.2 USB controller: Advanced Micro Devices, Inc. [AMD/ATI] SB7x0/SB8x0/SB9x0 USB EHCI Controller
00:14.0 SMBus: Advanced Micro Devices, Inc. [AMD/ATI] SBx00 SMBus Controller (rev 42)
00:14.2 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] SBx00 Azalia (Intel HDA) (rev 40)
00:14.3 ISA bridge: Advanced Micro Devices, Inc. [AMD/ATI] SB7x0/SB8x0/SB9x0 LPC host controller (rev 40)
00:14.4 PCI bridge: Advanced Micro Devices, Inc. [AMD/ATI] SBx00 PCI to PCI Bridge (rev 40)
00:14.5 USB controller: Advanced Micro Devices, Inc. [AMD/ATI] SB7x0/SB8x0/SB9x0 USB OHCI2 Controller
00:15.0 PCI bridge: Advanced Micro Devices, Inc. [AMD/ATI] SB700/SB800/SB900 PCI to PCI bridge (PCIE port 0)
00:15.1 PCI bridge: Advanced Micro Devices, Inc. [AMD/ATI] SB700/SB800/SB900 PCI to PCI bridge (PCIE port 1)
00:16.0 USB controller: Advanced Micro Devices, Inc. [AMD/ATI] SB7x0/SB8x0/SB9x0 USB OHCI0 Controller
00:16.2 USB controller: Advanced Micro Devices, Inc. [AMD/ATI] SB7x0/SB8x0/SB9x0 USB EHCI Controller
00:18.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 12h/14h Processor Function 0 (rev 43)
00:18.1 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 12h/14h Processor Function 1
00:18.2 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 12h/14h Processor Function 2
00:18.3 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 12h/14h Processor Function 3
00:18.4 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 12h/14h Processor Function 4
00:18.5 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 12h/14h Processor Function 6
00:18.6 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 12h/14h Processor Function 5
00:18.7 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 12h/14h Processor Function 7
04:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 06)

This is probably related to a confusing or nonsensical EDID returned by the display. I don't know what can be done about this in Haiku. Related to https://dev.haiku-os.org/ticket/13547

[mounty]

https://dev.haiku-os.org/ticket/13547 is fixed now so I no longer believe it is related to that ticket. The only difference is that the NUC described in this ticket is connected via the HDMI interface to the display, and the computer described in https://dev.haiku-os.org/ticket/13547 (a Wyse D10D thin client) is connected via DisplayPort.

[diver]

Please attach your syslog.

[bullfrog]

I have a Radeon HD 5450 PCI-e 1x that has the identical symptom on boot when it is the only card installed, on Walter hrev52853, x86_64. It gets through the icons, blanks, then nothing. If I install my older Radeon 9250 PCI, I can boot with the 9250 driving main monitor, with second monitor plugged into HD 5450. I get the multi-monitor selections in Screen prefs. The HD 5450 will not wake the monitor attached to it. This is same either upon boot or apply in Screen. Same if I swap monitors between cards. Only the 9250 works. Either monitor works normally when plugged into 9250. Both are 1440x900 Dell 19" lcd, using vga port.

[bullfrog]

syslog