Radeon drivers on PowerPC (e500)

[Martyn Welch <martyn.welch@ge.com>]

Hi,

I've been asked to try and get a r600 based (E6460) graphics card 
running on a machine powered by a Freescale p4080 (e500 core). I've run 
into a bit of a problem.

I have the driver built into the kernel at this point. When I boot the 
card is detected and it seems to be finding the fimware (I'm also 
building in the required firmware blobs), but I get the following messages:

[drm] Initialized drm 1.1.0 20060810
[drm] radeon defaulting to kernel modesetting.
[drm] radeon kernel modesetting enabled.
[drm] initializing kernel modesetting (CAICOS 0x1002:0x6763 0x1775:0xC6A7).
[drm] register mmio base: 0x10000000
[drm] register mmio size: 131072
ATOM BIOS: GE
[drm] GPU not posted. posting now...
radeon 0000:04:00.0: VRAM: 512M 0x0000000000000000 - 0x000000001FFFFFFF 
(512M used)
radeon 0000:04:00.0: GTT: 512M 0x0000000020000000 - 0x000000003FFFFFFF
[drm] Detected VRAM RAM=512M, BAR=256M
[drm] RAM width 64bits DDR
[TTM] Zone  kernel: Available graphics memory: 338754 kiB
[TTM] Zone highmem: Available graphics memory: 994110 kiB
[TTM] Initializing pool allocator
[TTM] Initializing DMA pool allocator
[drm] radeon: 512M of VRAM memory ready
[drm] radeon: 512M of GTT memory ready.
[drm] Supports vblank timestamp caching Rev 1 (10.10.2010).
[drm] Driver supports precise vblank timestamp query.
radeon 0000:04:00.0: radeon: using MSI.
[drm] radeon: irq initialized.
[drm] GART: num cpu pages 131072, num gpu pages 131072
[drm] probing gen 2 caps for device 111d:808a = 2/0
[drm] enabling PCIE gen 2 link speeds, disable with radeon.pcie_gen2=0
[drm] Loading CAICOS Microcode
__ioremap_caller(140000, 4096, 4194304, c02eab20)__ioremap(): phys addr 
0x140000 is RAM lr ttm_bo_kmap
radeon 0000:04:00.0: disabling GPU acceleration
radeon 0000:04:00.0: e957e400 unpin not necessary
radeon 0000:04:00.0: e957e400 unpin not necessary
[drm] Radeon Display Connectors
[drm] Connector 0:
[drm]   DP-1
[drm]   HPD2
[drm]   HPD3
[drm]   DDC: 0x6450 0x6450 0x6454 0x6454 0x6458 0x6458 0x645c 0x645c
[drm]   Encoders:
[drm]     DFP2: INTERNAL_UNIPHY1
[drm] Connector 2:
[drm]   DVI-I-1
[drm]   HPD1
[drm]   DDC: 0x6430 0x6430 0x6434 0x6434 0x6438 0x6438 0x643c 0x643c
[drm]   Encoders:
[drm]     DFP3: INTERNAL_UNIPHY
[drm]     CRT1: INTERNAL_KLDSCP_DAC1
[drm] Internal thermal controller with fan control
[drm] radeon: power management initialized
__ioremap_caller(141000, 5242880, 4194304, c02eab20)__ioremap(): phys 
addr 0x141000 is RAM lr ttm_bo_kmap
[drm:radeonfb_create] *ERROR* failed to create fbcon object -12
[drm] Initialized radeon 2.29.0 20080528 for 0000:04:00.0 on minor 0

There are failed attempts to ioremap RAM, initially as part of 
r600_vram_scratch_init() and again I guess mapping the GART?

On the e500, overlapping TLBs are not allowed and there is an explict 
check in arch/powerpc/mm/pgtable_32.c __ioremap_caller() to protect 
against ioremapping RAM that's already got TLB entries which is 
resulting in the error messages.

I'm out of ideas, any pointers or suggestions on how I might get this 
working? Has this ever been attempted before?

Martyn

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