From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from AM1EHSOBE005.bigfish.com (am1ehsobe005.messaging.microsoft.com [213.199.154.208]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (Client CN "mail.global.frontbridge.com", Issuer "Cybertrust SureServer Standard Validation CA" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 63773B708B for ; Wed, 1 Dec 2010 21:20:40 +1100 (EST) Received: from mail61-am1 (localhost.localdomain [127.0.0.1]) by mail61-am1-R.bigfish.com (Postfix) with ESMTP id 11FC7990530 for ; Wed, 1 Dec 2010 10:05:28 +0000 (UTC) Received: from AM1EHSMHS004.bigfish.com (unknown [10.3.201.243]) by mail61-am1.bigfish.com (Postfix) with ESMTP id AD77014E0050 for ; Wed, 1 Dec 2010 10:05:27 +0000 (UTC) Received: from az33smr01.freescale.net (az33smr01.freescale.net [10.64.34.199]) by az33egw01.freescale.net (8.14.3/8.14.3) with ESMTP id oB1A5Ke1007661 for ; Wed, 1 Dec 2010 03:05:20 -0700 (MST) Received: from zch01exm21.fsl.freescale.net (zch01exm21.ap.freescale.net [10.192.129.205]) by az33smr01.freescale.net (8.13.1/8.13.0) with ESMTP id oB1A5JqJ028890 for ; Wed, 1 Dec 2010 04:05:19 -0600 (CST) From: Mingkai Hu To: , Subject: [PATCH] eSPI: change the read behavior of the SPIRF Date: Wed, 1 Dec 2010 17:29:18 +0800 Message-ID: <1291195758-12322-1-git-send-email-Mingkai.hu@freescale.com> MIME-Version: 1.0 Content-Type: text/plain Cc: kumar.gala@freescale.com, Mingkai Hu List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , The user must read N bytes of SPIRF (1 <= N <= 4) that do not exceed the amount of data in the receive FIFO, so read the SPIRF byte by byte when the data in receive FIFO is less than 4 bytes. On Simics, when read N bytes that exceed the amout of data in receive FIFO, we can't read the data out, that is we can't clear the rx FIFO, then the CPU will loop on the espi rx interrupt. Signed-off-by: Mingkai Hu --- drivers/spi/spi_fsl_espi.c | 19 ++++++++++++++++--- 1 files changed, 16 insertions(+), 3 deletions(-) diff --git a/drivers/spi/spi_fsl_espi.c b/drivers/spi/spi_fsl_espi.c index e3b4f64..ae78926 100644 --- a/drivers/spi/spi_fsl_espi.c +++ b/drivers/spi/spi_fsl_espi.c @@ -507,16 +507,29 @@ void fsl_espi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events) /* We need handle RX first */ if (events & SPIE_NE) { - u32 rx_data; + u32 rx_data, tmp; + u8 rx_data_8; /* Spin until RX is done */ while (SPIE_RXCNT(events) < min(4, mspi->len)) { cpu_relax(); events = mpc8xxx_spi_read_reg(®_base->event); } - mspi->len -= 4; - rx_data = mpc8xxx_spi_read_reg(®_base->receive); + if (mspi->len >= 4) { + rx_data = mpc8xxx_spi_read_reg(®_base->receive); + } else { + tmp = mspi->len; + rx_data = 0; + while (tmp--) { + rx_data_8 = in_8((u8 *)®_base->receive); + rx_data |= (rx_data_8 << (tmp * 8)); + } + + rx_data <<= (4 - mspi->len) * 8; + } + + mspi->len -= 4; if (mspi->rx) mspi->get_rx(rx_data, mspi); -- 1.7.0.4