
Intel® 80219 General Purpose PCI Processor
6.The MTTR1 (Core 
| Problem: | The MTTR1 (Core  | 
| 
 | internal bus request signal (REQ#). All agents on the bus, except the core, maintain their assertion | 
| 
 | on REQ# signals upon receiving a retry. When the MCU is busy this means that the core must wait | 
| 
 | for other agents to complete their transactions before the core gains access to memory. Due to the | 
| 
 | fact that internal bus agents initiate larger transactions than the core, this issue results in an | 
| 
 | unbalanced access to the internal bus biased to these other agents (DMA, ATU, etc.). When opera- | 
| 
 | tional, the MTTR1 is intended to correct this balance. See Section 11.2.2 of the Intel® 80219 | 
| 
 | General Purpose PCI Processor Developer’s Manual for more information on the MTTR1 | 
| 
 | function. | 
| Implication: | In the case of the MCU internal bus target, this problem is compounded by the many internal bus | 
| 
 | retries that are issued by the MCU when under heavily loaded conditions. The result is that the | 
| 
 | internal bus arbiter removes the core access to the bus when the core deasserts REQ#. This | 
| 
 | condition may result in the core being locked out of accessing the MCU until other internal bus | 
| 
 | agents have completed their transaction(s) (i.e., when the DMA is in the process of a large block | 
| 
 | transfer of data, the core may have to wait until the DMA transaction is completed before it would | 
| 
 | have access to the internal bus to initiate its transaction). | 
| Workaround: | No workaround. | 
| Status: | NoFix. | 
7.The MCU supports a page size of 2 Kbytes for 64-bit  mode
| Problem: | The Intel® 80219 General Purpose PCI Processor Developer’s Manual (Section 6.1.1 and Section | 
| 
 | 6.2.2.3) states that the MCU supports a page size of 4 Kbytes for  | 
| 
 | |
| Implication: | The MCU supports a page size of 2 Kbytes for  | 
| Workaround: | No workaround. | 
| Status: | NoFix. | 
| 22 | Specification Update |