Samuel Thibault, le Thu 22 Apr 2010 16:51:38 +0200, a écrit : > Da Zheng, le Thu 22 Apr 2010 22:37:51 +0800, a écrit : > > So does the driver need to consider about cache coherency problems on PC > > when > > interacting with the external device? > > Yes (since you can not rely on the BIOS), you need to remap the mmio > range with cache disabled: INTEL_PTE_NCACHE|INTEL_PTE_WTHRU. This should > already be done by pmap_enter().
And you need to access it using the volatile qualifier. Samuel
