From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 31 Jan 2001 05:27:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 31 Jan 2001 05:27:04 -0500 Received: from colorfullife.com ([216.156.138.34]:19726 "EHLO colorfullife.com") by vger.kernel.org with ESMTP id ; Wed, 31 Jan 2001 05:26:56 -0500 Message-ID: <3A77E875.515B87C4@colorfullife.com> Date: Wed, 31 Jan 2001 11:27:01 +0100 From: Manfred Spraul X-Mailer: Mozilla 4.75 [en] (X11; U; Linux 2.2.16-22 i586) X-Accept-Language: en MIME-Version: 1.0 To: neufeld@linuxcare.com, linux-kernel@vger.kernel.org Subject: Re: Request: increase in PCI bus limit Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > > I'm working at a customer site with custom hardware. The 2.4.0 series > kernel almost works out of the box, but the machine has 52 PCI busses. > Plans are to produce a 4-way box which would have over 80 PCI busses. The > file include/asm-i386/mpspec.h allocates space for 32 busses in the > definition of the macro MAX_MP_BUSSES. > How long is the MP structure? smp_scan_config() reserves only 4 kB: reserve_bootmem(mpf->mpf_physptr, PAGE_SIZE); reserving the actual size (mpf->mpf_physptr->mpc_length) could be tricky. It should be possible to dynamically allocate the memory for the busses: It's not yet possible (smp_read_mpc() is called at a very early stage, before kmalloc is initialized), but we must move it to a later stage anyway: some Compaq bios version need ioremap() in smp_read_mpc(), and we should parse the ACPI tables for APIC descriptors (MADT, ia64 does that already). I'll add it to my TODO list. -- Manfred - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/