From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755083Ab0CVQ2b (ORCPT ); Mon, 22 Mar 2010 12:28:31 -0400 Received: from mail-fx0-f223.google.com ([209.85.220.223]:36348 "EHLO mail-fx0-f223.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754937Ab0CVQ23 convert rfc822-to-8bit (ORCPT ); Mon, 22 Mar 2010 12:28:29 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=gPlWULw9W+E4CukHZI+kBSaTbZFAVfaaCP0HZ1oZ+d+uzLRSpYt3ObWwcrgDGz2Iac k0Iwpgbh/dRRlC3sCwr2NEyHCxzjIeY9F5meSQZFkxgqQVKB5Z1VrwKLeuAWKQrPn8yz YPmZO7AOpbelKxVVL83MvEIrq9nIB9Uf4/T3U= MIME-Version: 1.0 In-Reply-To: <4BA72FC0.6060002@ladisch.de> References: <4BA72FC0.6060002@ladisch.de> Date: Mon, 22 Mar 2010 12:28:00 -0400 Message-ID: Subject: Re: [PATCH] PCI quirks: RS780/RS880: work around missing MSI initialization From: Alex Deucher To: Clemens Ladisch Cc: Jesse Barnes , linux-pci@vger.kernel.org, dri-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 22, 2010 at 4:52 AM, Clemens Ladisch wrote: > AMD says in section 2.5.4 (GFX MSI Enable) of #43291 (AMD 780G Family > Register Programming Requirements): > >  The SBIOS must enable internal graphics MSI capability in GCCFG by >  setting the following: NBCFG.NB_CNTL.STRAP_MSI_ENABLE='1' > > Quite a few BIOS writers misinterpret this sentence and think that > enabling MSI is an optional feature.  However, clearing that bit just > prevents delivery of MSI messages but does not remove the MSI PCI > capabilities registers, and so leaves these devices unusable for any > driver that attempts to use MSI. > > Setting that bit is not possible after the BIOS has locked down the > configuration registers, so we have to manually disable MSI for the > affected devices. > > This fixes the codec communication errors in the HDA driver when > accessing the HDMI audio device, and allows us to get rid of the > overcautious quirk in radeon_irq_kms.c. Looks good. This works properly on my rs780. Tested-by: Alex Deucher > > Signed-off-by: Clemens Ladisch > Cc: > --- >  drivers/pci/quirks.c                    |   31 +++++++++++++++++++++++++++++++ >  drivers/gpu/drm/radeon/radeon_irq_kms.c |    8 +------- >  2 files changed, 32 insertions(+), 7 deletions(-) > > --- a/drivers/pci/quirks.c > +++ b/drivers/pci/quirks.c > @@ -2479,6 +2479,39 @@ DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AT >  DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x4375, >                        quirk_msi_intx_disable_bug); > > +/* > + * MSI does not work with the AMD RS780/RS880 internal graphics and HDMI audio > + * devices unless the BIOS has initialized the nb_cntl.strap_msi_enable bit. > + */ > +static void __init rs780_int_gfx_disable_msi(struct pci_dev *int_gfx_bridge) > +{ > +       u32 nb_cntl; > + > +       if (!int_gfx_bridge->subordinate) > +               return; > + > +       pci_bus_write_config_dword(int_gfx_bridge->bus, PCI_DEVFN(0, 0), > +                                  0x60, 0); > +       pci_bus_read_config_dword(int_gfx_bridge->bus, PCI_DEVFN(0, 0), > +                                 0x64, &nb_cntl); > + > +       if (!(nb_cntl & BIT(10))) { > +               dev_warn(&int_gfx_bridge->dev, > +                        FW_WARN "RS780: MSI for internal graphics disabled\n"); > +               int_gfx_bridge->subordinate->bus_flags |= PCI_BUS_FLAGS_NO_MSI; > +       } > +} > + > +#define PCI_DEVICE_ID_AMD_RS780_P2P_INT_GFX    0x9602 > + > +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AMD, > +                       PCI_DEVICE_ID_AMD_RS780_P2P_INT_GFX, > +                       rs780_int_gfx_disable_msi); > +/* wrong vendor ID on M4A785TD motherboard: */ > +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ASUSTEK, > +                       PCI_DEVICE_ID_AMD_RS780_P2P_INT_GFX, > +                       rs780_int_gfx_disable_msi); > + >  #endif /* CONFIG_PCI_MSI */ > >  #ifdef CONFIG_PCI_IOV > --- a/drivers/gpu/drm/radeon/radeon_irq_kms.c > +++ b/drivers/gpu/drm/radeon/radeon_irq_kms.c > @@ -116,13 +116,7 @@ int radeon_irq_kms_init(struct radeon_de >        } >        /* enable msi */ >        rdev->msi_enabled = 0; > -       /* MSIs don't seem to work on my rs780; > -        * not sure about rs880 or other rs780s. > -        * Needs more investigation. > -        */ > -       if ((rdev->family >= CHIP_RV380) && > -           (rdev->family != CHIP_RS780) && > -           (rdev->family != CHIP_RS880)) { > +       if (rdev->family >= CHIP_RV380) { >                int ret = pci_enable_msi(rdev->pdev); >                if (!ret) { >                        rdev->msi_enabled = 1; >