From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756159AbbAWQNd (ORCPT ); Fri, 23 Jan 2015 11:13:33 -0500 Received: from mail-la0-f44.google.com ([209.85.215.44]:63677 "EHLO mail-la0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755862AbbAWQJI (ORCPT ); Fri, 23 Jan 2015 11:09:08 -0500 From: Ricardo Ribalda Delgado To: Mark Brown , Michal Simek , =?UTF-8?q?S=C3=B6ren=20Brinkmann?= , linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Ricardo Ribalda Delgado Subject: [PATCH 08/18] spi/xilinx: Support cores with no interrupt Date: Fri, 23 Jan 2015 17:08:40 +0100 Message-Id: <1422029330-10971-9-git-send-email-ricardo.ribalda@gmail.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1422029330-10971-1-git-send-email-ricardo.ribalda@gmail.com> References: <1422029330-10971-1-git-send-email-ricardo.ribalda@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The core can run in polling mode. In fact, the performance of the core is similar (or even better), due to the fact most of the spi transactions are just a couple of bytes and there is one irq per transactions. When an mtd device is connected via spi, reading 8MB of data produces more than 80K interrupts (with irq disabling, context swith....) Signed-off-by: Ricardo Ribalda Delgado --- drivers/spi/spi-xilinx.c | 33 +++++++++++++++++++-------------- 1 file changed, 19 insertions(+), 14 deletions(-) diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c index 3f8450d..8a28cab 100644 --- a/drivers/spi/spi-xilinx.c +++ b/drivers/spi/spi-xilinx.c @@ -173,8 +173,11 @@ static void xspi_init_hw(struct xilinx_spi *xspi) xspi->write_fn(XSPI_INTR_TX_EMPTY, regs_base + XIPIF_V123B_IIER_OFFSET); /* Enable the global IPIF interrupt */ - xspi->write_fn(XIPIF_V123B_GINTR_ENABLE, - regs_base + XIPIF_V123B_DGIER_OFFSET); + if (xspi->irq >= 0) + xspi->write_fn(XIPIF_V123B_GINTR_ENABLE, + regs_base + XIPIF_V123B_DGIER_OFFSET); + else + xspi->write_fn(0, regs_base + XIPIF_V123B_DGIER_OFFSET); /* Deselect the slave on the SPI bus */ xspi->write_fn(0xffff, regs_base + XSPI_SSR_OFFSET); /* Disable the transmitter, enable Manual Slave Select Assertion, @@ -264,7 +267,12 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) ~XSPI_CR_TRANS_INHIBIT; xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET); - wait_for_completion(&xspi->done); + if (xspi->irq >= 0) + wait_for_completion(&xspi->done); + else + while (!(xspi->read_fn(xspi->regs + XSPI_SR_OFFSET) & + XSPI_SR_TX_EMPTY_MASK)) + ; /* A transmit has just completed. Process received data and * check for more data to transmit. Always inhibit the @@ -412,20 +420,17 @@ static int xilinx_spi_probe(struct platform_device *pdev) xspi->buffer_size = xilinx_spi_find_buffer_size(xspi); - /* SPI controller initializations */ - xspi_init_hw(xspi); - xspi->irq = platform_get_irq(pdev, 0); - if (xspi->irq < 0) { - ret = xspi->irq; - goto put_master; + if (xspi->irq >= 0) { + /* Register for SPI Interrupt */ + ret = devm_request_irq(&pdev->dev, xspi->irq, xilinx_spi_irq, 0, + dev_name(&pdev->dev), xspi); + if (ret) + goto put_master; } - /* Register for SPI Interrupt */ - ret = devm_request_irq(&pdev->dev, xspi->irq, xilinx_spi_irq, 0, - dev_name(&pdev->dev), xspi); - if (ret) - goto put_master; + /* SPI controller initializations */ + xspi_init_hw(xspi); ret = spi_bitbang_start(&xspi->bitbang); if (ret) { -- 2.1.4 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ricardo Ribalda Delgado Subject: [PATCH 08/18] spi/xilinx: Support cores with no interrupt Date: Fri, 23 Jan 2015 17:08:40 +0100 Message-ID: <1422029330-10971-9-git-send-email-ricardo.ribalda@gmail.com> References: <1422029330-10971-1-git-send-email-ricardo.ribalda@gmail.com> Cc: Ricardo Ribalda Delgado To: Mark Brown , Michal Simek , =?UTF-8?q?S=C3=B6ren=20Brinkmann?= , linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Return-path: In-Reply-To: <1422029330-10971-1-git-send-email-ricardo.ribalda-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: The core can run in polling mode. In fact, the performance of the core is similar (or even better), due to the fact most of the spi transactions are just a couple of bytes and there is one irq per transactions. When an mtd device is connected via spi, reading 8MB of data produces more than 80K interrupts (with irq disabling, context swith....) Signed-off-by: Ricardo Ribalda Delgado --- drivers/spi/spi-xilinx.c | 33 +++++++++++++++++++-------------- 1 file changed, 19 insertions(+), 14 deletions(-) diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c index 3f8450d..8a28cab 100644 --- a/drivers/spi/spi-xilinx.c +++ b/drivers/spi/spi-xilinx.c @@ -173,8 +173,11 @@ static void xspi_init_hw(struct xilinx_spi *xspi) xspi->write_fn(XSPI_INTR_TX_EMPTY, regs_base + XIPIF_V123B_IIER_OFFSET); /* Enable the global IPIF interrupt */ - xspi->write_fn(XIPIF_V123B_GINTR_ENABLE, - regs_base + XIPIF_V123B_DGIER_OFFSET); + if (xspi->irq >= 0) + xspi->write_fn(XIPIF_V123B_GINTR_ENABLE, + regs_base + XIPIF_V123B_DGIER_OFFSET); + else + xspi->write_fn(0, regs_base + XIPIF_V123B_DGIER_OFFSET); /* Deselect the slave on the SPI bus */ xspi->write_fn(0xffff, regs_base + XSPI_SSR_OFFSET); /* Disable the transmitter, enable Manual Slave Select Assertion, @@ -264,7 +267,12 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) ~XSPI_CR_TRANS_INHIBIT; xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET); - wait_for_completion(&xspi->done); + if (xspi->irq >= 0) + wait_for_completion(&xspi->done); + else + while (!(xspi->read_fn(xspi->regs + XSPI_SR_OFFSET) & + XSPI_SR_TX_EMPTY_MASK)) + ; /* A transmit has just completed. Process received data and * check for more data to transmit. Always inhibit the @@ -412,20 +420,17 @@ static int xilinx_spi_probe(struct platform_device *pdev) xspi->buffer_size = xilinx_spi_find_buffer_size(xspi); - /* SPI controller initializations */ - xspi_init_hw(xspi); - xspi->irq = platform_get_irq(pdev, 0); - if (xspi->irq < 0) { - ret = xspi->irq; - goto put_master; + if (xspi->irq >= 0) { + /* Register for SPI Interrupt */ + ret = devm_request_irq(&pdev->dev, xspi->irq, xilinx_spi_irq, 0, + dev_name(&pdev->dev), xspi); + if (ret) + goto put_master; } - /* Register for SPI Interrupt */ - ret = devm_request_irq(&pdev->dev, xspi->irq, xilinx_spi_irq, 0, - dev_name(&pdev->dev), xspi); - if (ret) - goto put_master; + /* SPI controller initializations */ + xspi_init_hw(xspi); ret = spi_bitbang_start(&xspi->bitbang); if (ret) { -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 From: ricardo.ribalda@gmail.com (Ricardo Ribalda Delgado) Date: Fri, 23 Jan 2015 17:08:40 +0100 Subject: [PATCH 08/18] spi/xilinx: Support cores with no interrupt In-Reply-To: <1422029330-10971-1-git-send-email-ricardo.ribalda@gmail.com> References: <1422029330-10971-1-git-send-email-ricardo.ribalda@gmail.com> Message-ID: <1422029330-10971-9-git-send-email-ricardo.ribalda@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org The core can run in polling mode. In fact, the performance of the core is similar (or even better), due to the fact most of the spi transactions are just a couple of bytes and there is one irq per transactions. When an mtd device is connected via spi, reading 8MB of data produces more than 80K interrupts (with irq disabling, context swith....) Signed-off-by: Ricardo Ribalda Delgado --- drivers/spi/spi-xilinx.c | 33 +++++++++++++++++++-------------- 1 file changed, 19 insertions(+), 14 deletions(-) diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c index 3f8450d..8a28cab 100644 --- a/drivers/spi/spi-xilinx.c +++ b/drivers/spi/spi-xilinx.c @@ -173,8 +173,11 @@ static void xspi_init_hw(struct xilinx_spi *xspi) xspi->write_fn(XSPI_INTR_TX_EMPTY, regs_base + XIPIF_V123B_IIER_OFFSET); /* Enable the global IPIF interrupt */ - xspi->write_fn(XIPIF_V123B_GINTR_ENABLE, - regs_base + XIPIF_V123B_DGIER_OFFSET); + if (xspi->irq >= 0) + xspi->write_fn(XIPIF_V123B_GINTR_ENABLE, + regs_base + XIPIF_V123B_DGIER_OFFSET); + else + xspi->write_fn(0, regs_base + XIPIF_V123B_DGIER_OFFSET); /* Deselect the slave on the SPI bus */ xspi->write_fn(0xffff, regs_base + XSPI_SSR_OFFSET); /* Disable the transmitter, enable Manual Slave Select Assertion, @@ -264,7 +267,12 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) ~XSPI_CR_TRANS_INHIBIT; xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET); - wait_for_completion(&xspi->done); + if (xspi->irq >= 0) + wait_for_completion(&xspi->done); + else + while (!(xspi->read_fn(xspi->regs + XSPI_SR_OFFSET) & + XSPI_SR_TX_EMPTY_MASK)) + ; /* A transmit has just completed. Process received data and * check for more data to transmit. Always inhibit the @@ -412,20 +420,17 @@ static int xilinx_spi_probe(struct platform_device *pdev) xspi->buffer_size = xilinx_spi_find_buffer_size(xspi); - /* SPI controller initializations */ - xspi_init_hw(xspi); - xspi->irq = platform_get_irq(pdev, 0); - if (xspi->irq < 0) { - ret = xspi->irq; - goto put_master; + if (xspi->irq >= 0) { + /* Register for SPI Interrupt */ + ret = devm_request_irq(&pdev->dev, xspi->irq, xilinx_spi_irq, 0, + dev_name(&pdev->dev), xspi); + if (ret) + goto put_master; } - /* Register for SPI Interrupt */ - ret = devm_request_irq(&pdev->dev, xspi->irq, xilinx_spi_irq, 0, - dev_name(&pdev->dev), xspi); - if (ret) - goto put_master; + /* SPI controller initializations */ + xspi_init_hw(xspi); ret = spi_bitbang_start(&xspi->bitbang); if (ret) { -- 2.1.4