From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758166Ab0CaUhs (ORCPT ); Wed, 31 Mar 2010 16:37:48 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:45823 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757954Ab0CaUhq (ORCPT ); Wed, 31 Mar 2010 16:37:46 -0400 From: "Rafael J. Wysocki" To: Greg KH Subject: Re: [091/156] PCI quirk: RS780/RS880: work around missing MSI initialization Date: Wed, 31 Mar 2010 22:40:39 +0200 User-Agent: KMail/1.12.4 (Linux/2.6.34-rc3-rjw; KDE/4.3.5; x86_64; ; ) Cc: linux-kernel@vger.kernel.org, stable@kernel.org, stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Clemens Ladisch , Jesse Barnes References: <20100330224821.025709984@linux.site> In-Reply-To: <20100330224821.025709984@linux.site> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-2" Content-Transfer-Encoding: 7bit Message-Id: <201003312240.39444.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 31 March 2010, Greg KH wrote: > 2.6.33-stable review patch. If anyone has any objections, please let us know. I do, this one causes a regression to happen on my test box. Rafael > ------------------ > > From: Clemens Ladisch > > commit a5ee4eb75413c145334c30e43f1af9875dad6fd7 upstream. > > 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. > > Signed-off-by: Clemens Ladisch > Tested-by: Alex Deucher > Signed-off-by: Jesse Barnes > Signed-off-by: Greg Kroah-Hartman > > --- > drivers/gpu/drm/radeon/radeon_irq_kms.c | 8 ------- > drivers/pci/quirks.c | 33 ++++++++++++++++++++++++++++++++ > 2 files changed, 34 insertions(+), 7 deletions(-) > > --- 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; > --- a/drivers/pci/quirks.c > +++ b/drivers/pci/quirks.c > @@ -2484,6 +2484,39 @@ 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 > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > >