From mboxrd@z Thu Jan 1 00:00:00 1970 From: saiprakash.ranjan@codeaurora.org (Sai Prakash Ranjan) Date: Fri, 16 Nov 2018 16:39:56 +0530 Subject: [PATCH] boot_constraint: Add constraints for earlycon on dragonboard 410c In-Reply-To: <20181116105317.5zpbzhgt5cnssuki@vireshk-i7> References: <20181116104607.26671-1-saiprakash.ranjan@codeaurora.org> <20181116105317.5zpbzhgt5cnssuki@vireshk-i7> Message-ID: <83416a56-df25-caad-29be-a722f93c3008@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 11/16/2018 4:23 PM, Viresh Kumar wrote: > Hi, > > On 16-11-18, 16:16, Sai Prakash Ranjan wrote: >> iface clock is shared with other drivers, which may reconfigure >> this before the serial driver comes up. This may lead to >> crashes like the one below where GCC_BLSP1_AHB_CLK is same across >> multiple drivers like bam dma. >> >> <0>[ 3.164471] Internal error: synchronous external abort: 96000010 [#1] PREEMPT SMP >> <4>[ 3.164479] Modules linked in: >> <4>[ 3.164495] CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc8-00008-ge033b9909fff-dirty #175 >> <4>[ 3.164501] Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT) >> <4>[ 3.164508] pstate: 40000085 (nZcv daIf -PAN -UAO) >> <4>[ 3.164514] pc : msm_read.isra.2+0x20/0x50 >> <4>[ 3.164520] lr : msm_read.isra.2+0x1c/0x50 >> <4>[ 3.164526] sp : ffff000008033a50 >> <4>[ 3.164531] x29: ffff000008033a50 x28: ffff000009486018 >> <4>[ 3.164548] x27: 0000000000000001 x26: ffff7dfffe7ff070 >> <4>[ 3.164565] x25: 0000000000000034 x24: ffff000009486000 >> <4>[ 3.164582] x23: 0000000000000000 x22: ffff00000978e190 >> <4>[ 3.164599] x21: ffff0000095e8228 x20: 0000000000000034 >> <4>[ 3.164616] x19: ffff7dfffe7ff008 x18: ffffffffffffffff >> <4>[ 3.164632] x17: 0000000000000000 x16: 0000000000000000 >> <4>[ 3.164649] x15: ffff0000094a96c8 x14: ffff00008978e6bf >> <4>[ 3.164666] x13: ffff00000978e6cd x12: 0000000000000038 >> <4>[ 3.164683] x11: ffff0000094c6000 x10: 0000000000000c24 >> <4>[ 3.164699] x9 : ffff80003c89b400 x8 : ffff000008033970 >> <4>[ 3.164716] x7 : ffff80000eb04100 x6 : 00000000000af304 >> <4>[ 3.164732] x5 : 0000000000000c40 x4 : ffff80003c06f000 >> <4>[ 3.164750] x3 : ffff80003c89b498 x2 : 0000000000000000 >> <4>[ 3.164766] x1 : ffff80003ca68000 x0 : 0000000000000800 >> <0>[ 3.164785] Process swapper/0 (pid: 1, stack limit = 0x(____ptrval____)) >> <4>[ 3.164791] Call trace: >> <4>[ 3.164797] msm_read.isra.2+0x20/0x50 >> <4>[ 3.164804] msm_reset_dm_count+0x44/0x80 >> <4>[ 3.164810] __msm_console_write+0x1c8/0x1d0 >> <4>[ 3.164816] msm_serial_early_write_dm+0x3c/0x50 >> <4>[ 3.164823] console_unlock.part.6+0x468/0x528 >> <4>[ 3.164829] vprintk_emit+0x210/0x218 >> <4>[ 3.164835] vprintk_default+0x48/0x58 >> <4>[ 3.164841] vprintk_func+0xf0/0x1c0 >> <4>[ 3.164847] printk+0x74/0x94 >> <4>[ 3.164853] sci_init+0x24/0x3c >> <4>[ 3.164859] do_one_initcall+0x54/0x248 >> <4>[ 3.164866] kernel_init_freeable+0x210/0x378 >> <4>[ 3.164872] kernel_init+0x18/0x118 >> <4>[ 3.164878] ret_from_fork+0x10/0x1c >> <0>[ 3.164884] Code: aa1e03e0 8b214273 97e616f7 d503201f (b9400260) >> >> Link: https://lore.kernel.org/lkml/1cae8f10-55f5-20ce-9105-30af6f88bd6e at codeaurora.org/ >> Signed-off-by: Sai Prakash Ranjan >> >> --- >> >> This is purely dependent on boot constraint subsystem by Viresh. >> >> Link: https://lore.kernel.org/lkml/cover.1519380923.git.viresh.kumar at linaro.org/ >> --- >> drivers/soc/qcom/boot_constraint.c | 15 +++++++++++++++ >> 1 file changed, 15 insertions(+) > > Nice to see that the new subsystem has fixed your issue as well and > thanks for the patch. I am afraid though that this patch isn't going > to get merged anywhere as the subsystem isn't merged yet as Greg > wasn't too confident [1] about it. We are looking for more use-cases > apart from earlycon and clcd. > > Hi Viresh, Thanks for your time. I wanted to get this patch out so that once we have enough use cases, maybe we can add this as well. Thanks, Sai -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation