From patchwork Thu Jan 6 07:13:16 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shawn Guo X-Patchwork-Id: 77693 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 17CBBB70E0 for ; Thu, 6 Jan 2011 18:12:19 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754197Ab1AFHMJ (ORCPT ); Thu, 6 Jan 2011 02:12:09 -0500 Received: from va3ehsobe001.messaging.microsoft.com ([216.32.180.11]:28541 "EHLO VA3EHSOBE008.bigfish.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754030Ab1AFHMG (ORCPT ); Thu, 6 Jan 2011 02:12:06 -0500 Received: from mail85-va3-R.bigfish.com (10.7.14.248) by VA3EHSOBE008.bigfish.com (10.7.40.28) with Microsoft SMTP Server id 14.1.225.8; Thu, 6 Jan 2011 07:12:05 +0000 Received: from mail85-va3 (localhost.localdomain [127.0.0.1]) by mail85-va3-R.bigfish.com (Postfix) with ESMTP id 96FD811C85DA; Thu, 6 Jan 2011 07:12:05 +0000 (UTC) X-SpamScore: 0 X-BigFish: VS0(zzbb2cKc8kzz1202hzz8275bhz2dh2a8h668h61h) X-Spam-TCS-SCL: 0:0 X-Forefront-Antispam-Report: KIP:(null); UIP:(null); IPVD:NLI; H:de01egw02.freescale.net; RD:de01egw02.freescale.net; EFVD:NLI Received: from mail85-va3 (localhost.localdomain [127.0.0.1]) by mail85-va3 (MessageSwitch) id 1294297925311345_28660; Thu, 6 Jan 2011 07:12:05 +0000 (UTC) Received: from VA3EHSMHS029.bigfish.com (unknown [10.7.14.239]) by mail85-va3.bigfish.com (Postfix) with ESMTP id E9C7A195804C; Thu, 6 Jan 2011 07:12:04 +0000 (UTC) Received: from de01egw02.freescale.net (192.88.165.103) by VA3EHSMHS029.bigfish.com (10.7.99.39) with Microsoft SMTP Server (TLS) id 14.1.225.8; Thu, 6 Jan 2011 07:12:03 +0000 Received: from az33smr01.freescale.net (az33smr01.freescale.net [10.64.34.199]) by de01egw02.freescale.net (8.14.3/8.14.3) with ESMTP id p067C2PY013266; Thu, 6 Jan 2011 00:12:02 -0700 (MST) Received: from ubuntu.ap.freescale.net (ubuntu-010192242196.ap.freescale.net [10.192.242.196]) by az33smr01.freescale.net (8.13.1/8.13.0) with ESMTP id p067BL5x014249; Thu, 6 Jan 2011 01:11:58 -0600 (CST) From: Shawn Guo To: , , , , , , , , , , , , , , , Subject: [PATCH v4 08/10] ARM: mxs: add ocotp read function Date: Thu, 6 Jan 2011 15:13:16 +0800 Message-ID: <1294297998-26930-9-git-send-email-shawn.guo@freescale.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1294297998-26930-1-git-send-email-shawn.guo@freescale.com> References: <1294297998-26930-1-git-send-email-shawn.guo@freescale.com> MIME-Version: 1.0 X-OriginatorOrg: freescale.com Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Signed-off-by: Shawn Guo --- Changes for v4: - Call cpu_relax() during polling Changes for v2: - Add mutex locking for mxs_read_ocotp() - Use type size_t for count and i - Add comment for clk_enable/disable skipping - Add ERROR bit clearing and polling step arch/arm/mach-mxs/Makefile | 2 +- arch/arm/mach-mxs/include/mach/common.h | 1 + arch/arm/mach-mxs/ocotp.c | 79 +++++++++++++++++++++++++++++++ 3 files changed, 81 insertions(+), 1 deletions(-) create mode 100644 arch/arm/mach-mxs/ocotp.c diff --git a/arch/arm/mach-mxs/Makefile b/arch/arm/mach-mxs/Makefile index 39d3f9c..f23ebbd 100644 --- a/arch/arm/mach-mxs/Makefile +++ b/arch/arm/mach-mxs/Makefile @@ -1,5 +1,5 @@ # Common support -obj-y := clock.o devices.o gpio.o icoll.o iomux.o system.o timer.o +obj-y := clock.o devices.o gpio.o icoll.o iomux.o ocotp.o system.o timer.o obj-$(CONFIG_SOC_IMX23) += clock-mx23.o mm-mx23.o obj-$(CONFIG_SOC_IMX28) += clock-mx28.o mm-mx28.o diff --git a/arch/arm/mach-mxs/include/mach/common.h b/arch/arm/mach-mxs/include/mach/common.h index 59133eb..cf02552 100644 --- a/arch/arm/mach-mxs/include/mach/common.h +++ b/arch/arm/mach-mxs/include/mach/common.h @@ -13,6 +13,7 @@ struct clk; +extern int mxs_read_ocotp(int offset, int count, u32 *values); extern int mxs_reset_block(void __iomem *); extern void mxs_timer_init(struct clk *, int); diff --git a/arch/arm/mach-mxs/ocotp.c b/arch/arm/mach-mxs/ocotp.c new file mode 100644 index 0000000..e2d39aa --- /dev/null +++ b/arch/arm/mach-mxs/ocotp.c @@ -0,0 +1,79 @@ +/* + * Copyright 2010 Freescale Semiconductor, Inc. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include + +#include + +#define BM_OCOTP_CTRL_BUSY (1 << 8) +#define BM_OCOTP_CTRL_ERROR (1 << 9) +#define BM_OCOTP_CTRL_RD_BANK_OPEN (1 << 12) + +static DEFINE_MUTEX(ocotp_mutex); + +int mxs_read_ocotp(unsigned offset, size_t count, u32 *values) +{ + void __iomem *ocotp_base = MXS_IO_ADDRESS(MXS_OCOTP_BASE_ADDR); + int timeout = 0x400; + size_t i; + + mutex_lock(&ocotp_mutex); + + /* + * clk_enable(hbus_clk) for ocotp can be skipped + * as it must be on when system is running. + */ + + /* try to clear ERROR bit */ + __mxs_clrl(BM_OCOTP_CTRL_ERROR, ocotp_base); + + /* check both BUSY and ERROR cleared */ + while ((__raw_readl(ocotp_base) & + (BM_OCOTP_CTRL_BUSY | BM_OCOTP_CTRL_ERROR)) && --timeout) + cpu_relax(); + + if (unlikely(!timeout)) + goto error_unlock; + + /* open OCOTP banks for read */ + __mxs_setl(BM_OCOTP_CTRL_RD_BANK_OPEN, ocotp_base); + + /* approximately wait 32 hclk cycles */ + udelay(1); + + /* poll BUSY bit becoming cleared */ + timeout = 0x400; + while ((__raw_readl(ocotp_base) & BM_OCOTP_CTRL_BUSY) && --timeout) + cpu_relax(); + + if (unlikely(!timeout)) + goto error_unlock; + + for (i = 0; i < count; i++, offset += 4) + *values++ = __raw_readl(ocotp_base + offset); + + /* close banks for power saving */ + __mxs_clrl(BM_OCOTP_CTRL_RD_BANK_OPEN, ocotp_base); + + mutex_unlock(&ocotp_mutex); + + return 0; + +error_unlock: + mutex_unlock(&ocotp_mutex); + pr_err("%s: timeout in reading OCOTP\n", __func__); + return -ETIMEDOUT; +}