From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1aG1Tf-0003wz-Eb for barebox@lists.infradead.org; Mon, 04 Jan 2016 09:31:00 +0000 Date: Mon, 4 Jan 2016 10:30:37 +0100 From: Sascha Hauer Message-ID: <20160104093037.GG13058@pengutronix.de> References: <1451627918-31967-1-git-send-email-andrew.smirnov@gmail.com> <1451627918-31967-6-git-send-email-andrew.smirnov@gmail.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1451627918-31967-6-git-send-email-andrew.smirnov@gmail.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH 6/6] i.MX6: pci: Avoid aborts when asserting PCIe reset To: Andrey Smirnov Cc: barebox@lists.infradead.org, Lucas Stach The PCI patches look good to me. I'll give Lucas the change to look over them. Sascha On Thu, Dec 31, 2015 at 09:58:38PM -0800, Andrey Smirnov wrote: > When booting Barebox in the HW environment where PCIe core has been > used but not properly shut down, writing to PCIE_PL_PFLR in > imx6_pcie_assert_core_reset would cause data abort exception. > > The problem can be easily reproduced on a i.MX6 based board with PCIe > slot populated with some device by doing: > > > bootm -f -e 0x1050 .img > > Ignoring this exception seem to allow PCIe core to successfully > initialize and enumerate devices properly. This is also how Linux > Kernel version of the driver handles this situation -- it installs > dummy no-op abort handler at the beginning of device's probing. > > Signed-off-by: Andrey Smirnov > --- > drivers/pci/pci-imx6.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/pci/pci-imx6.c b/drivers/pci/pci-imx6.c > index 713007b..3a3edd8 100644 > --- a/drivers/pci/pci-imx6.c > +++ b/drivers/pci/pci-imx6.c > @@ -13,6 +13,7 @@ > > #include > #include > +#include > #include > #include > #include > @@ -237,7 +238,10 @@ static int imx6_pcie_assert_core_reset(struct pcie_port *pp) > val = readl(pp->dbi_base + PCIE_PL_PFLR); > val &= ~PCIE_PL_PFLR_LINK_STATE_MASK; > val |= PCIE_PL_PFLR_FORCE_LINK; > + > + data_abort_mask(); > writel(val, pp->dbi_base + PCIE_PL_PFLR); > + data_abort_unmask(); > > gpr12 &= ~IMX6Q_GPR12_PCIE_CTL_2; > writel(gpr12, imx6_pcie->iomuxc_gpr + IOMUXC_GPR12); > -- > 2.5.0 > > _______________________________________________ > barebox mailing list > barebox@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/barebox > -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox