From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755873AbbAWQJI (ORCPT ); Fri, 23 Jan 2015 11:09:08 -0500 Received: from mail-lb0-f178.google.com ([209.85.217.178]:54827 "EHLO mail-lb0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755847AbbAWQJD (ORCPT ); Fri, 23 Jan 2015 11:09:03 -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 05/18] spi/xilinx: Leave the IRQ always enabled. Date: Fri, 23 Jan 2015 17:08:37 +0100 Message-Id: <1422029330-10971-6-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 Instead of enabling the IRQ and disabling it for every transaction. Specially the small transactions (1,2 words) benefit from removing 3 bus accesses. Signed-off-by: Ricardo Ribalda Delgado --- drivers/spi/spi-xilinx.c | 19 +++++-------------- 1 file changed, 5 insertions(+), 14 deletions(-) diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c index 17480a2..408a842 100644 --- a/drivers/spi/spi-xilinx.c +++ b/drivers/spi/spi-xilinx.c @@ -167,8 +167,11 @@ static void xspi_init_hw(struct xilinx_spi *xspi) /* Reset the SPI device */ xspi->write_fn(XIPIF_V123B_RESET_MASK, regs_base + XIPIF_V123B_RESETR_OFFSET); - /* Disable all the interrupts just in case */ - xspi->write_fn(0, regs_base + XIPIF_V123B_IIER_OFFSET); + /* Enable the transmit empty interrupt, which we use to determine + * progress on the transmission. + */ + 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); @@ -237,7 +240,6 @@ static void xilinx_spi_fill_tx_fifo(struct xilinx_spi *xspi, int n_words) static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) { struct xilinx_spi *xspi = spi_master_get_devdata(spi->master); - u32 ipif_ier; /* We get here with transmitter inhibited */ @@ -246,14 +248,6 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) xspi->remaining_bytes = t->len; reinit_completion(&xspi->done); - - /* Enable the transmit empty interrupt, which we use to determine - * progress on the transmission. - */ - ipif_ier = xspi->read_fn(xspi->regs + XIPIF_V123B_IIER_OFFSET); - xspi->write_fn(ipif_ier | XSPI_INTR_TX_EMPTY, - xspi->regs + XIPIF_V123B_IIER_OFFSET); - for (;;) { u16 cr; int n_words; @@ -290,9 +284,6 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t) break; } - /* Disable the transmit empty interrupt */ - xspi->write_fn(ipif_ier, xspi->regs + XIPIF_V123B_IIER_OFFSET); - return t->len - xspi->remaining_bytes; } -- 2.1.4