Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759404Ab2JYM3O (ORCPT ); Thu, 25 Oct 2012 08:29:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33335 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756122Ab2JYM3K (ORCPT ); Thu, 25 Oct 2012 08:29:10 -0400 From: Mauro Carvalho Chehab Cc: Mauro Carvalho Chehab , Linux Edac Mailing List , Linux Kernel Mailing List Subject: [PATCH EDAC] edac: Fix the dimm filling for csrows-based layouts Date: Thu, 25 Oct 2012 10:29:02 -0200 Message-Id: <24bef66e74d647aebd34e0bef7693512b7912029.1351168139.git.mchehab@redhat.com> To: unlisted-recipients:; (no To-header on input) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3618 Lines: 102 The driver is currently filling data in a wrong way, on drivers for csrows-based memory controller, when the first layer is a csrow. This is not easily to notice, as, in general, memories are filed in dual, interleaved, symetric mode, as very few memory controllers support asymetric modes. While digging into a bug for i82795_edac driver, the asymetric mode there is now working, allowing us to fill the machine with 4x1GB ranks at channel 0, and 2x512GB at channel 1: Channel 0 ranks: EDAC DEBUG: i82975x_init_csrows: DIMM A0: from page 0x00000000 to 0x0003ffff (size: 0x00040000 pages) EDAC DEBUG: i82975x_init_csrows: DIMM A1: from page 0x00040000 to 0x0007ffff (size: 0x00040000 pages) EDAC DEBUG: i82975x_init_csrows: DIMM A2: from page 0x00080000 to 0x000bffff (size: 0x00040000 pages) EDAC DEBUG: i82975x_init_csrows: DIMM A3: from page 0x000c0000 to 0x000fffff (size: 0x00040000 pages) Channel 1 ranks: EDAC DEBUG: i82975x_init_csrows: DIMM B0: from page 0x00100000 to 0x0011ffff (size: 0x00020000 pages) EDAC DEBUG: i82975x_init_csrows: DIMM B1: from page 0x00120000 to 0x0013ffff (size: 0x00020000 pages) Instead of properly showing the memories as such, before this patch, it shows the memory layout as: +-----------------------------------+ | mc0 | | csrow0 | csrow1 | csrow2 | ----------+-----------------------------------+ channel1: | 1024 MB | 1024 MB | 512 MB | channel0: | 1024 MB | 1024 MB | 512 MB | ----------+-----------------------------------+ as if both channels were symetric, grouping the DIMMs on a wrong layout. After this patch, the memory is correctly represented. So, for csrows at layers[0], it shows: +-----------------------------------------------+ | mc0 | | csrow0 | csrow1 | csrow2 | csrow3 | ----------+-----------------------------------------------+ channel1: | 512 MB | 512 MB | 0 MB | 0 MB | channel0: | 1024 MB | 1024 MB | 1024 MB | 1024 MB | ----------+-----------------------------------------------+ For csrows at layers[1], it shows: +-----------------------+ | mc0 | | channel0 | channel1 | --------+-----------------------+ csrow3: | 1024 MB | 0 MB | csrow2: | 1024 MB | 0 MB | --------+-----------------------+ csrow1: | 1024 MB | 512 MB | csrow0: | 1024 MB | 512 MB | --------+-----------------------+ So, no matter of what comes first, the information between channel and csrow will be properly represented. Signed-off-by: Mauro Carvalho Chehab --- drivers/edac/edac_mc.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/edac/edac_mc.c b/drivers/edac/edac_mc.c index d5dc9da..81eb9fd 100644 --- a/drivers/edac/edac_mc.c +++ b/drivers/edac/edac_mc.c @@ -416,10 +416,18 @@ struct mem_ctl_info *edac_mc_alloc(unsigned mc_num, dimm->cschannel = chn; /* Increment csrow location */ - row++; - if (row == tot_csrows) { - row = 0; + if (layers[0].is_virt_csrow) { chn++; + if (chn == tot_channels) { + chn = 0; + row++; + } + } else { + row++; + if (row == tot_csrows) { + row = 0; + chn++; + } } /* Increment dimm location */ -- 1.7.11.7 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/