From patchwork Fri Feb 25 17:54:35 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Philip Rakity X-Patchwork-Id: 590681 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id p1PHsv6a030763 for ; Fri, 25 Feb 2011 17:54:57 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754455Ab1BYRy4 (ORCPT ); Fri, 25 Feb 2011 12:54:56 -0500 Received: from na3sys009aog117.obsmtp.com ([74.125.149.242]:35246 "EHLO na3sys009aog117.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755640Ab1BYRyz convert rfc822-to-8bit (ORCPT ); Fri, 25 Feb 2011 12:54:55 -0500 Received: from source ([65.219.4.129]) (using TLSv1) by na3sys009aob117.postini.com ([74.125.148.12]) with SMTP ID DSNKTWfs5MAnI+PopaSJjZZ7X86uoV9uS9g9@postini.com; Fri, 25 Feb 2011 09:54:55 PST Received: from SC-vEXCH3.marvell.com ([10.93.76.133]) by SC-OWA01.marvell.com ([10.93.76.21]) with mapi; Fri, 25 Feb 2011 09:53:19 -0800 From: Philip Rakity To: "linux-mmc@vger.kernel.org" CC: Kyungmin Park , Wolfram Sang , Jae hoon Chung , Chuanxiao Dong , "linux-kernel@vger.kernel.org" Date: Fri, 25 Feb 2011 09:54:35 -0800 Subject: [PATCH] sdhci: always use max timeout for xfers Thread-Topic: [PATCH] sdhci: always use max timeout for xfers Thread-Index: AcvVFRDLGDyPwNNmTCuS5RdfFc6aCQ== Message-ID: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US MIME-Version: 1.0 Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter1.kernel.org [140.211.167.41]); Fri, 25 Feb 2011 17:54:57 +0000 (UTC) ===== The card/host controller may sometimes return a value that is too low and cause the h/w to timeout a transfer that would have worked. Using the maximum value avoids this. Signed-off-by: Philip Rakity --- drivers/mmc/host/sdhci.c | 48 ++++----------------------------------------- 1 files changed, 5 insertions(+), 43 deletions(-) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 655617c..dd99da8 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -592,53 +592,15 @@ static void sdhci_adma_table_post(struct sdhci_host *host, data->sg_len, direction); } -static u8 sdhci_calc_timeout(struct sdhci_host *host, struct mmc_data *data) +static inline u8 sdhci_calc_timeout(void) { - u8 count; - unsigned target_timeout, current_timeout; - /* - * If the host controller provides us with an incorrect timeout - * value, just skip the check and use 0xE. The hardware may take + * The host controller/card can provide us with an incorrect timeout + * value, just use the maximum value 0xE. The hardware may take * longer to time out, but that's much better than having a too-short * timeout value. */ - if (host->quirks & SDHCI_QUIRK_BROKEN_TIMEOUT_VAL) - return 0xE; - - /* timeout in us */ - target_timeout = data->timeout_ns / 1000 + - data->timeout_clks / host->clock; - - if (host->quirks & SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK) - host->timeout_clk = host->clock / 1000; - - /* - * Figure out needed cycles. - * We do this in steps in order to fit inside a 32 bit int. - * The first step is the minimum timeout, which will have a - * minimum resolution of 6 bits: - * (1) 2^13*1000 > 2^22, - * (2) host->timeout_clk < 2^16 - * => - * (1) / (2) > 2^6 - */ - count = 0; - current_timeout = (1 << 13) * 1000 / host->timeout_clk; - while (current_timeout < target_timeout) { - count++; - current_timeout <<= 1; - if (count >= 0xF) - break; - } - - if (count >= 0xF) { - printk(KERN_WARNING "%s: Too large timeout requested!\n", - mmc_hostname(host->mmc)); - count = 0xE; - } - - return count; + return 0xE; } static void sdhci_set_transfer_irqs(struct sdhci_host *host) @@ -671,7 +633,7 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_data *data) host->data = data; host->data_early = 0; - count = sdhci_calc_timeout(host, data); + count = sdhci_calc_timeout(); sdhci_writeb(host, count, SDHCI_TIMEOUT_CONTROL); if (host->flags & (SDHCI_USE_SDMA | SDHCI_USE_ADMA))