From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from AM1EHSOBE004.bigfish.com (am1ehsobe004.messaging.microsoft.com [213.199.154.207]) (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 6DE25B7082 for ; Tue, 21 Dec 2010 13:05:47 +1100 (EST) From: Mingkai Hu To: , Subject: [PATCH 1/2] eSPI: change the read behavior of the SPIRF Date: Tue, 21 Dec 2010 09:26:07 +0800 Message-ID: <1292894768-6737-1-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 --- The patch 2/2 is againsted on this patch, so I resent this patch again for convience which sent several weeks ago. 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); -- 1.6.4