From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt To: Gabriel Paubert , Subject: Re: PATCH: improved processor config for G3s Date: Tue, 5 Sep 2000 12:50:25 +0200 Message-Id: <20000905105025.300@mailhost.mipsys.com> In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: > >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 ?) ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/