<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <style type="text/css" style="display:none;"> P {margin-top:0;margin-bottom:0;} </style> </head> <body dir="ltr"> <div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof ContentPasted0"> > Hi Carl, <div class="ContentPasted0">></div> <div class="ContentPasted0">>>>> besides this, ask a dumb question.</div> <div class="ContentPasted0">>>>> How we retrieve the pat_index from a shared resource though dma_buf fd?</div> <div class="ContentPasted0">>>>> maybe we need to know whether it could be CPU cached if we want map it.</div> <div class="ContentPasted0">>>>> Of course, looks there are no real usage to access it though CPU.</div> <div class="ContentPasted0">>>>> Just use it directly without any pat related options ?</div> <div class="ContentPasted0">>>></div> <div class="ContentPasted0">>>> I am not understanding. Do you want to ask the PAT table to the driver? Are</div> <div class="ContentPasted0">>>> you referring to the CPU PAT index?</div> <div class="ContentPasted0">>>></div> <div class="ContentPasted0">>>> In any case, if I understood correctly, you don't necessarily always need to</div> <div class="ContentPasted0">>>> set the PAT options and the cache options will fall into the default values.</div> <div class="ContentPasted0">>>></div> <div class="ContentPasted0">>>> Please let me know if I haven't answered the question.</div> <div class="ContentPasted0">>>></div> <div class="ContentPasted0">>></div> <div class="ContentPasted0">>> If mesa create a resource , then use DRM_IOCTL_PRIME_HANDLE_TO_FD convert it to a dma fd.</div> <div class="ContentPasted0">>> Then share it to media, media use DRM_IOCTL_PRIME_FD_TO_HANDLE convert it to a gem bo.</div> <div class="ContentPasted0">>> But media does not know the PAT index , because mesa create it and set it.</div> <div class="ContentPasted0">>> So, if media want to call DRM_IOCTL_I915_GEM_MMAP_OFFSET, media does not know whether it could be WB.</div> <div class="ContentPasted0">></div> <div class="ContentPasted0">> That's a good point. To be honest I am not really sure how this</div> <div class="ContentPasted0">> is handled.</div> <div class="ContentPasted0">></div> <div class="ContentPasted0">> Fei, Jordan? Do you have suggestion here?</div> <div><br class="ContentPasted0"> </div> <div class="ContentPasted0">Is it possible to pass the PAT setting when sharing the fd?</div> <div class="ContentPasted0">Or perhaps we should have kept the get_caching ioctl functional?</div> <div class="ContentPasted0">Joonas, could you chime in here?</div> <div><br class="ContentPasted0"> </div> > Andi<br> </div> </body> </html>