static IMG_VOID
PVRLinuxX86PATProbe(IMG_VOID)
{
/*
* cpu_has_pat indicates whether PAT support is available on the CPU,
* but doesn't indicate if it has been enabled.
*/
if (cpu_has_pat) /* PRQA S 3335 */ /* ignore 'no function declared' */
{
u64 pat;
IMG_UINT pat_index;
IMG_UINT pat_entry;
PVR_TRACE(("%s: PAT available", __FUNCTION__));
/*
* There is no Linux API for finding out if write combining
* is avaialable through the PAT, so we take the direct
* approach, and see if the PAT MSR contains a write combining
* entry.
*/
rdmsrl(MSR_IA32_CR_PAT, pat);
PVR_TRACE(("%s: Top 32 bits of PAT: 0x%.8x", __FUNCTION__, (IMG_UINT)(pat >> 32)));
PVR_TRACE(("%s: Bottom 32 bits of PAT: 0x%.8x", __FUNCTION__, (IMG_UINT)(pat)));
pat_index = pvr_pat_index(_PAGE_CACHE_WC);
PVR_TRACE(("%s: PAT index for write combining: %u", __FUNCTION__, pat_index));
pat_entry = pvr_pat_entry(pat, pat_index);
PVR_TRACE(("%s: PAT entry for write combining: 0x%.2x (should be 0x%.2x)", __FUNCTION__, pat_entry, PAT_LINUX_X86_WC));
#if defined(SUPPORT_LINUX_X86_WRITECOMBINE)
g_write_combining_available = (IMG_BOOL)(pat_entry == PAT_LINUX_X86_WC);
#endif
}
#if defined(DEBUG)
#if defined(SUPPORT_LINUX_X86_WRITECOMBINE)
if (g_write_combining_available)
{
PVR_TRACE(("%s: Write combining available via PAT", __FUNCTION__));
}
else
{
PVR_TRACE(("%s: Write combining not available", __FUNCTION__));
}
#else /* defined(SUPPORT_LINUX_X86_WRITECOMBINE) */
PVR_TRACE(("%s: Write combining disabled in driver build", __FUNCTION__));
#endif /* defined(SUPPORT_LINUX_X86_WRITECOMBINE) */
#endif /* DEBUG */
}
static IMG_VOID
PVRLinuxX86PATProbe(IMG_VOID)
{
if (cpu_has_pat)
{
u64 pat;
IMG_UINT pat_index;
IMG_UINT pat_entry;
PVR_TRACE(("%s: PAT available", __FUNCTION__));
rdmsrl(MSR_IA32_CR_PAT, pat);
PVR_TRACE(("%s: Top 32 bits of PAT: 0x%.8x", __FUNCTION__, (IMG_UINT)(pat >> 32)));
PVR_TRACE(("%s: Bottom 32 bits of PAT: 0x%.8x", __FUNCTION__, (IMG_UINT)(pat)));
pat_index = pvr_pat_index(_PAGE_CACHE_WC);
PVR_TRACE(("%s: PAT index for write combining: %u", __FUNCTION__, pat_index));
pat_entry = pvr_pat_entry(pat, pat_index);
PVR_TRACE(("%s: PAT entry for write combining: 0x%.2x (should be 0x%.2x)", __FUNCTION__, pat_entry, PAT_LINUX_X86_WC));
#if defined(SUPPORT_LINUX_X86_WRITECOMBINE)
g_write_combining_available = (IMG_BOOL)(pat_entry == PAT_LINUX_X86_WC);
#endif
}
#if defined(DEBUG)
#if defined(SUPPORT_LINUX_X86_WRITECOMBINE)
if (g_write_combining_available)
{
PVR_TRACE(("%s: Write combining available via PAT", __FUNCTION__));
}
else
{
PVR_TRACE(("%s: Write combining not available", __FUNCTION__));
}
#else
PVR_TRACE(("%s: Write combining disabled in driver build", __FUNCTION__));
#endif
#endif
}