From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kukjin Kim Subject: RE: [v2 PATCH 0/2] EXYNOS: Fix low level debug support Date: Wed, 24 Jul 2013 17:01:53 +0900 Message-ID: <0e8501ce8844$0f5eae60$2e1c0b20$@org> References: <1373806020-7336-1-git-send-email-yadi.brar@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: Received: from mailout2.samsung.com ([203.254.224.25]:37569 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751894Ab3GXICE (ORCPT ); Wed, 24 Jul 2013 04:02:04 -0400 Received: from epcpsbgr5.samsung.com (u145.gpu120.samsung.co.kr [203.254.230.145]) by mailout2.samsung.com (Oracle Communications Messaging Server 7u4-24.01 (7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0MQF00DNKKZ6AAN0@mailout2.samsung.com> for linux-samsung-soc@vger.kernel.org; Wed, 24 Jul 2013 17:01:54 +0900 (KST) In-reply-to: <1373806020-7336-1-git-send-email-yadi.brar@samsung.com> Content-language: ko Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: 'Yadwinder Singh Brar' Cc: linux-samsung-soc@vger.kernel.org, arnd@arndb.de, olof@lixom.net, dianders@chromium.org, thomas.abraham@linaro.org, t.figa@samsung.com, yadi.brar01@gmail.com Yadwinder Singh Brar wrote: > > Presently, using exynos_defconfig with CONFIG_DEBUG_LL and > CONFIG_EARLY_PRINTK > on, kernel is not booting, we are getting following: > > [ 0.000000] ------------[ cut here ]------------ > [ 0.000000] kernel BUG at mm/vmalloc.c:1134! > [ 0.000000] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM > [ 0.000000] Modules linked in: > [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 3.11.0-rc1 #633 > [ 0.000000] task: c052ec48 ti: c0524000 task.ti: c0524000 > [ 0.000000] PC is at vm_area_add_early+0x54/0x94 > [ 0.000000] LR is at add_static_vm_early+0xc/0x60 > > Its because exynos[4/5]_map_io() function ioremaps a single 512KB memory > size for all the four uart ports which envelopes the mapping created by > debug_ll_io_init(), called earlier in exynos_init_io(). > > This issue seems to be occured after : > commit ee4de5d99aeac44f4507b7538b2b3faedc5205b9 > ARM: 7781/1: mmu: Add debug_ll_io_init() mappings to early mappings > > This series removes static iodesc entries for UART controller for all > Samsung > SoC's and modifies pm debug code to save/restore only the selected debug > uart > registers. > > changes since v1: > - removed uart iodesc entires instead of just moving inside > CONFIG_DEBUG_LL > check, as suggested by Thomas Abraham. > - Fixed the possible issue after removing uart entries pointed by Tomasz > Figa. > > Tested doing suspend/resume on smdk5250. > > Yadwinder Singh Brar (2): > ARM: SAMSUNG: pm: Save/restore only selected uart's registers > ARM: EXYNOS: Fix low level debug support > > arch/arm/mach-exynos/common.c | 26 -------------------------- > arch/arm/plat-samsung/pm.c | 14 +++----------- > 2 files changed, 3 insertions(+), 37 deletions(-) This series looks good to me, applied into -fixes. Just note, I was looking at the static iodesc for UART because of booting problem ;) Anyway, thanks, Kukjin