Re: PATCH: improved processor config for G3s

The absence of broadcast might definitely harm, but first the support for
store gathering in the MPC106 (Grackle) is quite poor:

"For a stream of single-beat writes, the data for the first transaction is
latched in the first buffer and the MPC106 initiates the transaction on
the PCI bus. The second single-beat write is then stored in the second
buffer. For subsequent single-beat writes, store gathering is possible if
the incoming write is to sequential bytes in the same half cache line as
the previously latched data. Store gathering is only used for writes to
PCI memory space, not for writes to PCI I/O space. The store gathering
continues until the buffer is scheduled to be flushed or until the
processor issues a synchronizing transaction.

Well, that would help unaccelerated frame buffers (but are there any on
Grackle-based machines ?)


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