Alexey Kardashevskiy <aik@xxxxxxxxx> writes: > H_PUT_TCE_INDIRECT allows packing up to 512 TCE updates into a single > hypercall; H_STUFF_TCE can clear lots in a single hypercall too. > > However, unlike H_STUFF_TCE (which writes the same TCE to all entries), > H_PUT_TCE_INDIRECT uses a 4K page with new TCEs. In a secure VM > environment this means sharing a secure VM page with a hypervisor which > we would rather avoid. > > This splits the FW_FEATURE_MULTITCE feature into FW_FEATURE_PUT_TCE_IND > and FW_FEATURE_STUFF_TCE. "hcall-multi-tce" in > the "/rtas/ibm,hypertas-functions" device tree property sets both; > the "multitce=off" kernel command line parameter disables both. > > This should not cause behavioural change. > > Signed-off-by: Alexey Kardashevskiy <aik@xxxxxxxxx> Reviewed-by: Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxx> Tested-by: Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxx> -- Thiago Jung Bauermann IBM Linux Technology Center
