Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756080Ab3ENHPn (ORCPT ); Tue, 14 May 2013 03:15:43 -0400 Received: from lgeamrelo01.lge.com ([156.147.1.125]:59126 "EHLO LGEAMRELO01.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751177Ab3ENHPl (ORCPT ); Tue, 14 May 2013 03:15:41 -0400 X-AuditID: 9c93017d-b7b62ae000004f69-bc-5191e49bbc0e From: "Jongsung Kim" To: "'Stephen Warren'" Cc: "'Russell King'" , "'Greg Kroah-Hartman'" , , , , , References: <007301ce375e$bcf6d6b0$36e48410$@lge.com> <5191D200.3040604@wwwdotorg.org> In-Reply-To: <5191D200.3040604@wwwdotorg.org> Subject: RE: [PATCH] ARM: PL011: add support for extended FIFO-size of PL011-r1p5 Date: Tue, 14 May 2013 16:15:39 +0900 Organization: LG Electronics Message-ID: <01fd01ce5072$d6b9fcd0$842df670$@lge.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 14.0 Thread-Index: AQHInDuhqkp37yHuVjCbmrHEKQdwAwJ2699/mPvokRA= Content-Language: ko X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1274 Lines: 36 Stephen Warren : > For reference, the AMBA periphid of the UART device there is 0x00341011. > The nibble "3" is the revision being tested in: The UART device has periphid 0x00341011, and is compatible with the original PL011 prior to r1p5. Not with r1p5. It could be a possible way to specify the compatible periphid (such as 0x00241011) instead of just 0x0 when initializing the amba_device for the UART. > > +static unsigned int get_fifosize_arm(unsigned int periphid) > > +{ > > + unsigned int rev = (periphid >> 20) & 0xf; > > + return rev < 3 ? 16 : 32; > > +} > > Should that be <= not <, or is there just something more wrong in the > patch or bcm2835 HW? I wonder how r1p5 maps to 3 in the test above. >From the PL011-r1p5 TRM, bits[7:4] of the UARTPeriphID2 register are read as: r1p0 - 0x0 r1p1 - 0x1 r1p3 - 0x2 r1p4 - 0x2 r1p5 - 0x3. Doesn't the BCM2835 UART have anything different from the ARM PL011? What about the UARTPCellID registers? They are set to 0xb105f00d with the ARM PL011. -- 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/