From mboxrd@z Thu Jan 1 00:00:00 1970 From: Subodh Nijsure Message-Id: <200103290653.WAA01744@shell9.ba.best.com> Subject: DPRAM parameters for 860P To: linuxppc-embedded@lists.linuxppc.org Date: Wed, 28 Mar 2001 22:53:59 -0800 (PST) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: Hello, Currently the 2.4.2 code assumes that DPRAM is always 4KB has anybody put together m8xx_cpm_dpalloc() that takes advantage of larger DPRAM on 860P? ->From arch/ppc/kernel/8xx_io/commproc.c /* The dual ported RAM is multi-functional. Some areas can be (and are * being) used for microcode. There is an area that can only be used * as data ram for buffer descriptors, which is all we use right now. * Currently the first 512 and last 256 bytes are used for microcode. */ #define CPM_DATAONLY_BASE ((uint)0x0800) /*#define CPM_DATAONLY_SIZE ((uint)0x0700)*/ /* Above definition assumes we have 4KB DPRAM but 860P has 8KB, so * we experiment. My RCCR , RMDS says DATA size of 0x3400 is safe */ #define CPM_DATAONLY_SIZE ((uint)0x3400) #define CPM_DP_NOSPACE ((uint)0x7fffffff) I have been running my system with above configuration for couple of days without any problems. Are there any side effects I should be aware of? 2. Anybody knows if there a driver currently that uses the 8xx IDMA to transfer data from a peripheral to CPU and back? /Subodh Nijsure ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/