Bug#931901: Clarifying this issue, delt with on OFTC in #debian

The R600 /is/ newer than this card.. as R600 was code name for the HD 2000 series in 2007 and this card is an HD 6000 series from 2010 however, the problem seems to be that the buster kernel 4.19 assumes that ALL cards after this R600 in 2007 require firmware, when that doesn't seem to be true in this case.

This is the drm output from the same machine running the stretch 4.9 and the buster 4.19 kernels.. it shows in buster that immediately after drm enables radeon KMS it does a radeon_pci_probe_ and errors out saying the card requires firmware, but when booting 4.9 it continues and properly loads the card and KMS successfully.. same system, same firmwares available..

Furthermore upon searching, I see no evidence the 1002:9802 a.k.a HD 6310 a.k.a "Wrestler" has ever had firmware available.. it may have some sort already on the card somewhere, but there are no firmwares matching that pciid, codename, or model number anywhere that I can see.

Therefore a change yet to be identified by commit/line/author was made that makes incorrect assumptions about radeon cards based on their age / date of mfg.

Buster Kernel
-------------
[ 4.504541] [drm] radeon kernel modesetting enabled.
[ 4.505318] [drm:radeon_pci_probe [radeon]] *ERROR* radeon kernel modesetting for R600 or later requires firmware installed

Stretch Kernel
--------------
[ 2.551075] [drm] Initialized
[ 2.678699] [drm] radeon kernel modesetting enabled.
[ 2.696263] fb: switching to radeondrmfb from EFI VGA
[ 2.698166] [drm] initializing kernel modesetting (PALM 0x1002:0x9802 0x17AA:0x21FD 0x00).
[ 2.698202] [drm] register mmio base: 0xF0B00000
[ 2.698204] [drm] register mmio size: 262144
[ 2.698423] [drm] Detected VRAM RAM=384M, BAR=256M
[ 2.698425] [drm] RAM width 32bits DDR
[ 2.698706] [drm] radeon: 384M of VRAM memory ready
[ 2.698708] [drm] radeon: 1024M of GTT memory ready.
[ 2.698743] [drm] Loading PALM Microcode
[ 2.698921] [drm] Internal thermal controller without fan control
[ 2.699034] [drm] Found smc ucode version: 0x00010601
[ 2.699124] [drm] radeon: dpm initialized
[ 2.699464] [drm] GART: num cpu pages 262144, num gpu pages 262144
[ 2.723113] [drm] PCIE GART of 1024M enabled (table at 0x0000000000162000).
[ 2.723935] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[ 2.723937] [drm] Driver supports precise vblank timestamp query.
[ 2.724090] [drm] radeon: irq initialized.
[ 2.741566] [drm] ring test on 0 succeeded in 1 usecs
[ 2.741586] [drm] ring test on 3 succeeded in 3 usecs
[ 2.787420] [drm] ring test on 5 succeeded in 1 usecs
[ 2.807288] [drm] UVD initialized successfully.
[ 2.808260] [drm] ib test on ring 0 succeeded in 0 usecs
[ 2.808317] [drm] ib test on ring 3 succeeded in 0 usecs
[ 3.348656] [drm] ib test on ring 5 succeeded
[ 3.432601] [drm] radeon atom DIG backlight initialized
[ 3.432609] [drm] Radeon Display Connectors
[ 3.432614] [drm] Connector 0:
[ 3.432616] [drm] LVDS-1
[ 3.432618] [drm] HPD1
[ 3.432622] [drm] DDC: 0x6430 0x6430 0x6434 0x6434 0x6438 0x6438 0x643c 0x643c
[ 3.432623] [drm] Encoders:
[ 3.432625] [drm] LCD1: INTERNAL_UNIPHY
[ 3.432626] [drm] Connector 1:
[ 3.432628] [drm] HDMI-A-1
[ 3.432629] [drm] HPD2
[ 3.432633] [drm] DDC: 0x6440 0x6440 0x6444 0x6444 0x6448 0x6448 0x644c 0x644c
[ 3.432634] [drm] Encoders:
[ 3.432635] [drm] DFP1: INTERNAL_UNIPHY
[ 3.432636] [drm] Connector 2:
[ 3.432638] [drm] VGA-1
[ 3.432641] [drm] DDC: 0x64d8 0x64d8 0x64dc 0x64dc 0x64e0 0x64e0 0x64e4 0x64e4
[ 3.432642] [drm] Encoders:
[ 3.432644] [drm] CRT1: INTERNAL_KLDSCP_DAC1
[ 3.871131] [drm] fb mappable at 0xE0366000
[ 3.871134] [drm] vram apper at 0xE0000000
[ 3.871137] [drm] size 4325376
[ 3.871139] [drm] fb depth is 24
[ 3.871140] [drm] pitch is 5632
[ 3.871567] fbcon: radeondrmfb (fb0) is primary device
[ 4.456993] radeon 0000:00:01.0: fb0: radeondrmfb frame buffer device
[ 4.481506] [drm] Initialized radeon 2.49.0 20080528 for 0000:00:01.0 on minor 0