Register Description
12.2.66Offset 178h: PREFCTRL—Prefetch Control Register
The following register contains prefetch parameters for PCI operation.
Table 100. | Offset 178h: | |||||
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| Type | Reset |
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| Description |
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63:60 |
| RsvdP | 0000b | Preserved |
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| Prefetch Policy (PP): These bits control how the bridge prefetches data on behalf of PCI | ||
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| • | 00 = | Allow prefetching on MRM, MRL, and MR. |
55:54 |
| RW | 01b | • | 01 = | Allow prefetching on MRM and MRL, but not on memory read. |
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| • | 1x = | Disable all prefetching. |
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| NOTE: This control applies to both inbound memory reads and peer reads to the other PCI | ||
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| segment in the Intel® 41210 Serial to Parallel PCI Bridge. | |
53:22 |
| RsvdP | 0 | Preserved |
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21:16 |
| RW | 05h | TH 66: These bits indicate the threshold parameter for 66 MHz PCI. Unit is 64B chunks and | ||
| is 0s based; in other words, a value of 0 in this field indicates 64B. | |||||
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15:11 |
| RsvdP | 00h | Preserved |
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10:5 |
| RW | 03h | TH 33: These bits indicate the threshold parameter for 33 MHz PCI. Unit is 64B chunks and | ||
| is 0s based; in other words, a value of 0 in this field indicates 64B. | |||||
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4:0 |
| RsvdP | 00h | Preserved |
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Intel® 41210 Serial to Parallel PCI Bridge Developer’s Manual | 119 |