From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758330Ab3APQFd (ORCPT ); Wed, 16 Jan 2013 11:05:33 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:36275 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932307Ab3APQF1 (ORCPT ); Wed, 16 Jan 2013 11:05:27 -0500 From: Herton Ronaldo Krzesinski To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Wolfram Sang , Artem Bityutskiy , Herton Ronaldo Krzesinski Subject: [PATCH 125/222] mtd: nand: gpmi: reset BCH earlier, too, to avoid NAND startup problems Date: Wed, 16 Jan 2013 13:55:25 -0200 Message-Id: <1358351822-7675-126-git-send-email-herton.krzesinski@canonical.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1358351822-7675-1-git-send-email-herton.krzesinski@canonical.com> References: <1358351822-7675-1-git-send-email-herton.krzesinski@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.5.7.3 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Wolfram Sang commit 6f2a6a52560ad8d85710aabd92b7a3239b3a6b07 upstream. It could happen (1 out of 100 times) that NAND did not start up correctly after warm rebooting, so the kernel could not find the UBI or DMA timed out due to a stalled BCH. When resetting BCH together with GPMI, the issue could not be observed anymore (after 10000+ reboots). We probably need the consistent state already before sending any command to NAND, even when no ECC is needed. I chose to keep the extra reset for BCH when changing the flash layout to be on the safe side. Signed-off-by: Wolfram Sang Acked-by: Huang Shijie Signed-off-by: Artem Bityutskiy Signed-off-by: Herton Ronaldo Krzesinski --- drivers/mtd/nand/gpmi-nand/gpmi-lib.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c index a1f4332..b27e215 100644 --- a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c +++ b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c @@ -136,6 +136,15 @@ int gpmi_init(struct gpmi_nand_data *this) if (ret) goto err_out; + /* + * Reset BCH here, too. We got failures otherwise :( + * See later BCH reset for explanation of MX23 handling + */ + ret = gpmi_reset_block(r->bch_regs, GPMI_IS_MX23(this)); + if (ret) + goto err_out; + + /* Choose NAND mode. */ writel(BM_GPMI_CTRL1_GPMI_MODE, r->gpmi_regs + HW_GPMI_CTRL1_CLR); -- 1.7.9.5