64 bit Trisquel and 32 bit graphics

Um, i just figured my machine can run the Trisquel 6.0 64-bit version.
Everything works just fine, though i dunno what is going on on the graphics side. Graphics work well, i just don't know how.

The machine is a Macbook2,1 Mid 2007. It boots in 32-bit EFI mode and loads the 64-bit kernel. The CPU is 64-bit able: http://ark.intel.com/products/27255/Intel-Core2-Duo-Processor-T7200-4M-Cache-2_00-GHz-667-MHz-FSB

$ uname -a
Linux MyMachine 3.8.5-gnu #1 SMP Thu Mar 28 21:33:10 PDT 2013 x86_64 x86_64 x86_64 GNU/Linux

For the graphics it says:

$ sudo lshw -c video
  *-display:0             
       description: VGA compatible controller
       product: Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller
       vendor: Intel Corporation
       physical id: 2
       bus info: pci@0000:00:02.0
       version: 03
       width: 32 bits
       clock: 33MHz
       capabilities: msi pm vga_controller bus_master cap_list rom
       configuration: driver=i915 latency=0
       resources: irq:16 memory:d0380000-d03fffff ioport:20e0(size=8) memory:c0000000-cfffffff memory:d0400000-d043ffff
  *-display:1 UNCLAIMED
       description: Display controller
       product: Mobile 945GM/GMS/GME, 943/940GML Express Integrated Graphics Controller
       vendor: Intel Corporation
       physical id: 2.1
       bus info: pci@0000:00:02.1
       version: 03
       width: 32 bits
       clock: 33MHz
       capabilities: pm cap_list
       configuration: latency=0
       resources: memory:d0300000-d037ffff

so there is some 32-bit thing about the graphics card. but the driver again is 64-bit:

$ file /lib/modules/3.8.5-gnu/kernel/drivers/gpu/drm/i915/i915.ko
/lib/modules/3.8.5-gnu/kernel/drivers/gpu/drm/i915/i915.ko: ELF 64-bit LSB relocatable, x86-64, version 1 (SYSV), BuildID[sha1]=0x55f457d3d49b6158a2170ed218c2520589f902fc, not stripped

please help me understand how and why this works
cheers Mono