Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757323Ab1FFNWv (ORCPT ); Mon, 6 Jun 2011 09:22:51 -0400 Received: from mail-px0-f179.google.com ([209.85.212.179]:59315 "EHLO mail-px0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755785Ab1FFNWs convert rfc822-to-8bit (ORCPT ); Mon, 6 Jun 2011 09:22:48 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=rE9dQRc8WtN2Ax0Us09YmZR50EYY+761CQtPg88scK4OuBZ3IgSc987yPSgVYu0ROe PmbtfpxMV0g4i7mg3PQE5OyVCx/86CS8yfrlzcWHCrp44GwXCPBMgS/gbH8/hWs0GINz OkngVrsWzI2PUFEzm0HgDkd+Mner0kOQCdwlM= MIME-Version: 1.0 In-Reply-To: References: <1305128885-21275-1-git-send-email-per.forlin@linaro.org> <1305128885-21275-2-git-send-email-per.forlin@linaro.org> Date: Mon, 6 Jun 2011 15:22:48 +0200 Message-ID: Subject: Re: [PATCH v5] sdio: optimized SDIO IRQ handling for single irq From: Daniel Mack To: Chris Ball Cc: Per Forlin , linux-mmc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linaro-dev@lists.linaro.org, Stefan Nilsson XK , "John W. Linville" , Dan Williams , libertas-dev@lists.infradead.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5020 Lines: 122 On Mon, Jun 6, 2011 at 3:17 PM, Daniel Mack wrote: > On Wed, May 11, 2011 at 6:45 PM, Chris Ball wrote: >> Hi Per, >> >> On Wed, May 11 2011, Per Forlin wrote: >>> From: Stefan Nilsson XK >>> >>> If there is only 1 function interrupt registered it is possible to >>> improve performance by directly calling the irq handler >>> and avoiding the overhead of reading the CCCR registers. >>> >>> Signed-off-by: Per Forlin >>> Acked-by: Ulf Hansson >>> Reviewed-by: Nicolas Pitre >>> --- >>> ?drivers/mmc/core/sdio_irq.c | ? 33 ++++++++++++++++++++++++++++++++- >>> ?include/linux/mmc/card.h ? ?| ? ?1 + >>> ?2 files changed, 33 insertions(+), 1 deletions(-) >>> >>> diff --git a/drivers/mmc/core/sdio_irq.c b/drivers/mmc/core/sdio_irq.c >>> index bb192f9..a0890ac 100644 >>> --- a/drivers/mmc/core/sdio_irq.c >>> +++ b/drivers/mmc/core/sdio_irq.c >>> @@ -31,6 +31,17 @@ static int process_sdio_pending_irqs(struct mmc_card *card) >>> ?{ >>> ? ? ? int i, ret, count; >>> ? ? ? unsigned char pending; >>> + ? ? struct sdio_func *func; >>> + >>> + ? ? /* >>> + ? ? ?* Optimization, if there is only 1 function interrupt registered >>> + ? ? ?* call irq handler directly >>> + ? ? ?*/ >>> + ? ? func = card->sdio_single_irq; >>> + ? ? if (func) { >>> + ? ? ? ? ? ? func->irq_handler(func); >>> + ? ? ? ? ? ? return 1; >>> + ? ? } >>> >>> ? ? ? ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_INTx, 0, &pending); >>> ? ? ? if (ret) { >>> @@ -42,7 +53,7 @@ static int process_sdio_pending_irqs(struct mmc_card *card) >>> ? ? ? count = 0; >>> ? ? ? for (i = 1; i <= 7; i++) { >>> ? ? ? ? ? ? ? if (pending & (1 << i)) { >>> - ? ? ? ? ? ? ? ? ? ? struct sdio_func *func = card->sdio_func[i - 1]; >>> + ? ? ? ? ? ? ? ? ? ? func = card->sdio_func[i - 1]; >>> ? ? ? ? ? ? ? ? ? ? ? if (!func) { >>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? printk(KERN_WARNING "%s: pending IRQ for " >>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? "non-existant function\n", >>> @@ -186,6 +197,24 @@ static int sdio_card_irq_put(struct mmc_card *card) >>> ? ? ? return 0; >>> ?} >>> >>> +/* If there is only 1 function registered set sdio_single_irq */ >>> +static void sdio_single_irq_set(struct mmc_card *card) >>> +{ >>> + ? ? struct sdio_func *func; >>> + ? ? int i; >>> + >>> + ? ? card->sdio_single_irq = NULL; >>> + ? ? if ((card->host->caps & MMC_CAP_SDIO_IRQ) && >>> + ? ? ? ? card->host->sdio_irqs == 1) >>> + ? ? ? ? ? ? for (i = 0; i < card->sdio_funcs; i++) { >>> + ? ? ? ? ? ? ? ? ? ?func = card->sdio_func[i]; >>> + ? ? ? ? ? ? ? ? ? ?if (func && func->irq_handler) { >>> + ? ? ? ? ? ? ? ? ? ? ? ? ? ?card->sdio_single_irq = func; >>> + ? ? ? ? ? ? ? ? ? ? ? ? ? ?break; >>> + ? ? ? ? ? ? ? ? ? ?} >>> + ? ? ? ? ? ?} >>> +} >>> + >>> ?/** >>> ? * ? sdio_claim_irq - claim the IRQ for a SDIO function >>> ? * ? @func: SDIO function >>> @@ -227,6 +256,7 @@ int sdio_claim_irq(struct sdio_func *func, sdio_irq_handler_t *handler) >>> ? ? ? ret = sdio_card_irq_get(func->card); >>> ? ? ? if (ret) >>> ? ? ? ? ? ? ? func->irq_handler = NULL; >>> + ? ? sdio_single_irq_set(func->card); >>> >>> ? ? ? return ret; >>> ?} >>> @@ -251,6 +281,7 @@ int sdio_release_irq(struct sdio_func *func) >>> ? ? ? if (func->irq_handler) { >>> ? ? ? ? ? ? ? func->irq_handler = NULL; >>> ? ? ? ? ? ? ? sdio_card_irq_put(func->card); >>> + ? ? ? ? ? ? sdio_single_irq_set(func->card); >>> ? ? ? } >>> >>> ? ? ? ret = mmc_io_rw_direct(func->card, 0, 0, SDIO_CCCR_IENx, 0, ®); >>> diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h >>> index d8dffc9..4910dec 100644 >>> --- a/include/linux/mmc/card.h >>> +++ b/include/linux/mmc/card.h >>> @@ -191,6 +191,7 @@ struct mmc_card { >>> ? ? ? struct sdio_cccr ? ? ? ?cccr; ? ? ? ? ? /* common card info */ >>> ? ? ? struct sdio_cis ? ? ? ? cis; ? ? ? ? ? ?/* common tuple info */ >>> ? ? ? struct sdio_func ? ? ? ?*sdio_func[SDIO_MAX_FUNCS]; /* SDIO functions (devices) */ >>> + ? ? struct sdio_func ? ? ? ?*sdio_single_irq; /* SDIO function when only one IRQ active */ >>> ? ? ? unsigned ? ? ? ? ? ? ? ?num_info; ? ? ? /* number of info strings */ >>> ? ? ? const char ? ? ? ? ? ? ?**info; ? ? ? ? /* info strings */ >>> ? ? ? struct sdio_func_tuple ?*tuples; ? ? ? ?/* unknown common tuples */ >> >> Thanks, looks good now -- pushed to mmc-next for .40. > > This patch breaks libertas over SDIO, as the interrupt handler of that > driver is now called even though the hardware didn't signal any > interrupt condition. This is a problem for at least two reasons in > this case: I checked the libertas-dev archives too late and saw that there is a fix by Daniel Drake for this problem already. Sorry for the noise. Daniel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/