From mboxrd@z Thu Jan 1 00:00:00 1970 From: daniel@caiaq.de (Daniel Mack) Date: Mon, 3 May 2010 13:26:42 +0200 Subject: [PATCH] ARM: mx3: Fix a race condition in mxcmmc In-Reply-To: <20100427102442.GD30801@buzzloop.caiaq.de> References: <20100427075012.GB30801@buzzloop.caiaq.de> <20100427102442.GD30801@buzzloop.caiaq.de> Message-ID: <20100503112642.GI30807@buzzloop.caiaq.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Sascha, can you take this to your tree? On Tue, Apr 27, 2010 at 12:24:42PM +0200, Daniel Mack wrote: > From cefcdab08d1c9636c4a7290bc2bbe937d051bce4 Mon Sep 17 00:00:00 2001 > From: Volker Ernst > Date: Mon, 26 Apr 2010 22:51:07 +0200 > Subject: [PATCH] ARM: mx3: Fix a race condition in mxcmmc > > This fixes a race condition regarding interrupt bits in the SDHC > controller driver code. > > In case of PIO-transfer it does not clear SDHC-status bit#11/12 > in the INT-handler anymore. INT-handler might be called during > an ongoing PIO-data-transfer (with some other INT-flag set) and > PIO-transfer depends on these bits being set to detect the end > of the data-transfer. This also means that at the end of PIO- > transfer that PIO-software has to clear these bits itself. > > However in case of DMA-transfer these bits have to be cleared > in the INT-handler, because they are used to generate INTs then. > > Works solid, no more problems here, can transfer big files. > > Signed-off-by: Volker Ernst > Acked-by: Daniel Mack > Cc: Andy Green > --- > drivers/mmc/host/mxcmmc.c | 13 ++++++++++++- > 1 files changed, 12 insertions(+), 1 deletions(-) > > diff --git a/drivers/mmc/host/mxcmmc.c b/drivers/mmc/host/mxcmmc.c > index 2c53024..ec18e3b 100644 > --- a/drivers/mmc/host/mxcmmc.c > +++ b/drivers/mmc/host/mxcmmc.c > @@ -489,6 +489,9 @@ static void mxcmci_datawork(struct work_struct *work) > struct mxcmci_host *host = container_of(work, struct mxcmci_host, > datawork); > int datastat = mxcmci_transfer_data(host); > + > + writel(STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE, > + host->base + MMC_REG_STATUS); > mxcmci_finish_data(host, datastat); > > if (host->req->stop) { > @@ -553,7 +556,8 @@ static irqreturn_t mxcmci_irq(int irq, void *devid) > u32 stat; > > stat = readl(host->base + MMC_REG_STATUS); > - writel(stat & ~STATUS_SDIO_INT_ACTIVE, host->base + MMC_REG_STATUS); > + writel(stat & ~(STATUS_SDIO_INT_ACTIVE | STATUS_DATA_TRANS_DONE | > + STATUS_WRITE_OP_DONE), host->base + MMC_REG_STATUS); > > dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat); > > @@ -561,6 +565,13 @@ static irqreturn_t mxcmci_irq(int irq, void *devid) > sdio_irq = (stat & STATUS_SDIO_INT_ACTIVE) && host->use_sdio; > spin_unlock_irqrestore(&host->lock, flags); > > +#ifdef HAS_DMA > + if (mxcmci_use_dma(host) && > + (stat & (STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE))) > + writel(STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE, > + host->base + MMC_REG_STATUS); > +#endif > + > if (sdio_irq) { > writel(STATUS_SDIO_INT_ACTIVE, host->base + MMC_REG_STATUS); > mmc_signal_sdio_irq(host->mmc); > -- > 1.7.0.3 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel at lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel