From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 14AE1B7C98 for ; Thu, 11 Feb 2010 13:40:13 +1100 (EST) Subject: Re: [PATCH] powerpc/40x: Add support for PPC40x boards with > 512MB SDRAM From: Benjamin Herrenschmidt To: Stefan Roese In-Reply-To: <1265810099-31355-1-git-send-email-sr@denx.de> References: <1265810099-31355-1-git-send-email-sr@denx.de> Content-Type: text/plain; charset="UTF-8" Date: Thu, 11 Feb 2010 13:39:56 +1100 Message-ID: <1265855996.16346.7.camel@pasglop> Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 2010-02-10 at 14:54 +0100, Stefan Roese wrote: > This patch adds support for boards with more that 512MByte RAM. Currently > only 512MB of memory are enabled in the DCCR/ICCR real-mode cache > control registers. This patch now enables caching in real-mode for > 2GByte. Should we make that conditional to how much memory is populated ? Or it doesn't matter ? I suppose we don't do IO accesses in real mode anyways so no big deal... Cheers, Ben. > Signed-off-by: Stefan Roese > Cc: Benjamin Herrenschmidt > Cc: Josh Boyer > --- > arch/powerpc/mm/40x_mmu.c | 4 ++-- > 1 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/powerpc/mm/40x_mmu.c b/arch/powerpc/mm/40x_mmu.c > index 08dfa8e..65abfcf 100644 > --- a/arch/powerpc/mm/40x_mmu.c > +++ b/arch/powerpc/mm/40x_mmu.c > @@ -84,8 +84,8 @@ void __init MMU_init_hw(void) > * vectors and the kernel live in real-mode. > */ > > - mtspr(SPRN_DCCR, 0xF0000000); /* 512 MB of data space at 0x0. */ > - mtspr(SPRN_ICCR, 0xF0000000); /* 512 MB of instr. space at 0x0. */ > + mtspr(SPRN_DCCR, 0xFFFF0000); /* 2GByte of data space at 0x0. */ > + mtspr(SPRN_ICCR, 0xFFFF0000); /* 2GByte of instr. space at 0x0. */ > } > > #define LARGE_PAGE_SIZE_16M (1<<24)