From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Maupin, Chase" Subject: RE: [PATCH] mmc: omap_hsmmc: set dto to 14 for all devices Date: Tue, 6 Mar 2012 12:54:34 +0000 Message-ID: <7D46E86EC0A8354091174257B2FED1012F050F72@DLEE12.ent.ti.com> References: <1330622780-1909-1-git-send-email-Chase.Maupin@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 8BIT Return-path: Received: from bear.ext.ti.com ([192.94.94.41]:39045 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751772Ab2CFMyg convert rfc822-to-8bit (ORCPT ); Tue, 6 Mar 2012 07:54:36 -0500 In-Reply-To: <1330622780-1909-1-git-send-email-Chase.Maupin@ti.com> Content-Language: en-US Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: "Maupin, Chase" , "linux-omap@vger.kernel.org" , "linux-mmc@vger.kernel.org" Ping on this patch. I have not seen any response on the list but if I have missed something please let me know. > -----Original Message----- > From: Maupin, Chase > Sent: Thursday, March 01, 2012 11:26 AM > To: linux-omap@vger.kernel.org; linux-mmc@vger.kernel.org > Cc: Maupin, Chase > Subject: [PATCH] mmc: omap_hsmmc: set dto to 14 for all devices > > * With certain SD cards timeouts like the following have been seen > due to an improper calculation of the dto value: > mmcblk0: error -110 transferring data, sector 4126233, nr 8, > card status 0xc00 > * By removing the dto calculation and setting the timeout value > to the maximum specified by the SD card specification part A2 > section 2.2.15 these timeouts can be avoided. > * This change has been used by beagleboard users as well as the > Texas Instruments SDK without a negative impact. > * There are multiple discussion threads about this but the most > relevant ones are: > * http://talk.maemo.org/showthread.php?p=1000707#post1000707 > * http://www.mail-archive.com/linux- > omap@vger.kernel.org/msg42213.html > * Original proposal for this fix was done by Sukumar Ghoral of > Texas Instruments > > * Tested using a Texas Instruments AM335x EVM > > Signed-off-by: Chase Maupin > --- > drivers/mmc/host/omap_hsmmc.c | 30 +++++------------------------ > - > 1 files changed, 5 insertions(+), 25 deletions(-) > > diff --git a/drivers/mmc/host/omap_hsmmc.c > b/drivers/mmc/host/omap_hsmmc.c > index fd0c661..afd7292 100644 > --- a/drivers/mmc/host/omap_hsmmc.c > +++ b/drivers/mmc/host/omap_hsmmc.c > @@ -1481,11 +1481,8 @@ static int > omap_hsmmc_start_dma_transfer(struct omap_hsmmc_host *host, > return 0; > } > > -static void set_data_timeout(struct omap_hsmmc_host *host, > - unsigned int timeout_ns, > - unsigned int timeout_clks) > +static void set_data_timeout(struct omap_hsmmc_host *host) > { > - unsigned int timeout, cycle_ns; > uint32_t reg, clkd, dto = 0; > > reg = OMAP_HSMMC_READ(host->base, SYSCTL); > @@ -1493,25 +1490,8 @@ static void set_data_timeout(struct > omap_hsmmc_host *host, > if (clkd == 0) > clkd = 1; > > - cycle_ns = 1000000000 / (clk_get_rate(host->fclk) / clkd); > - timeout = timeout_ns / cycle_ns; > - timeout += timeout_clks; > - if (timeout) { > - while ((timeout & 0x80000000) == 0) { > - dto += 1; > - timeout <<= 1; > - } > - dto = 31 - dto; > - timeout <<= 1; > - if (timeout && dto) > - dto += 1; > - if (dto >= 13) > - dto -= 13; > - else > - dto = 0; > - if (dto > 14) > - dto = 14; > - } > + /* Use the maximum timeout value allowed in the standard of 14 > or 0xE */ > + dto = 14; > > reg &= ~DTO_MASK; > reg |= dto << DTO_SHIFT; > @@ -1534,13 +1514,13 @@ omap_hsmmc_prepare_data(struct > omap_hsmmc_host *host, struct mmc_request *req) > * busy signal. > */ > if (req->cmd->flags & MMC_RSP_BUSY) > - set_data_timeout(host, 100000000U, 0); > + set_data_timeout(host); > return 0; > } > > OMAP_HSMMC_WRITE(host->base, BLK, (req->data->blksz) > | (req->data->blocks << 16)); > - set_data_timeout(host, req->data->timeout_ns, req->data- > >timeout_clks); > + set_data_timeout(host); > > if (host->use_dma) { > ret = omap_hsmmc_start_dma_transfer(host, req); > -- > 1.7.0.4