diff options
| author | Clemens Ladisch <clemens@ladisch.de> | 2010-03-22 11:52:16 +0300 |
|---|---|---|
| committer | Jesse Barnes <jbarnes@virtuousgeek.org> | 2010-03-24 23:21:38 +0300 |
| commit | a5ee4eb75413c145334c30e43f1af9875dad6fd7 (patch) | |
| tree | 721f45ddafb0934dcd445de47bea9c1d0ad3efe2 /drivers/gpu | |
| parent | ca8463926306580c25e62eb901a206530d480cae (diff) | |
| download | linux-a5ee4eb75413c145334c30e43f1af9875dad6fd7.tar.xz | |
PCI quirk: RS780/RS880: work around missing MSI initialization
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 <clemens@ladisch.de>
Tested-by: Alex Deucher <alexdeucher@gamil.com>
Cc: <stable@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/radeon/radeon_irq_kms.c | 8 |
1 files changed, 1 insertions, 7 deletions
diff --git a/drivers/gpu/drm/radeon/radeon_irq_kms.c b/drivers/gpu/drm/radeon/radeon_irq_kms.c index 3cfd60fd0083..ea4c645ece11 100644 --- 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_device *rdev) } /* 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; |