Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758574Ab3EOJhe (ORCPT ); Wed, 15 May 2013 05:37:34 -0400 Received: from caramon.arm.linux.org.uk ([78.32.30.218]:50438 "EHLO caramon.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755230Ab3EOJhd (ORCPT ); Wed, 15 May 2013 05:37:33 -0400 Date: Wed, 15 May 2013 10:37:13 +0100 From: Russell King - ARM Linux To: Stephen Warren Cc: Jongsung Kim , "'Greg Kroah-Hartman'" , jslaby@suse.cz, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] ARM: PL011: add support for extended FIFO-size of PL011-r1p5 Message-ID: <20130515093713.GJ18614@n2100.arm.linux.org.uk> References: <007301ce375e$bcf6d6b0$36e48410$@lge.com> <5191D200.3040604@wwwdotorg.org> <01fd01ce5072$d6b9fcd0$842df670$@lge.com> <5192A692.4010700@wwwdotorg.org> <022d01ce5107$8bc668e0$a3533aa0$@lge.com> <5193164E.6050400@wwwdotorg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5193164E.6050400@wwwdotorg.org> User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 959 Lines: 18 On Tue, May 14, 2013 at 10:59:58PM -0600, Stephen Warren wrote: > Well, that certainly isn't true in practice. I think we should revert > this commit until we can determine what the problem is. > > I validated that the periphid register in HW contains the r1p5 revision > (3), and the pcellid register does indeed contain the expected > 0xb105f00d value. However, if I run the following hacky code in U-Boot > to determine the FIFO depth, it comes out as 16, which explains the > symptoms I'm seeing: We could do that, just like we do in 8250.c to check the FIFO depth. There's not much harm in doing that at boot time, it just needs to be done carefully so that it doesn't disrupt any existing use of the UART. -- 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/