3.16.7-ckt3 -stable review patch. If anyone has any objections, please let me know.
------------------ From: Benjamin Herrenschmidt <[email protected]> commit 91ed6fd2c383bb8f02d66e98b4a4d2f7207249dc upstream. Some radeon ASICs don't support all 64 address bits of MSIs despite advertising support for 64-bit MSIs in their configuration space. This breaks on systems such as IBM POWER7/8, where 64-bit MSIs can be assigned with some of the high address bits set. This makes use of the newly introduced "no_64bit_msi" flag in structure pci_dev to allow the MSI allocation code to fallback to 32-bit MSIs on those adapters. Signed-off-by: Benjamin Herrenschmidt <[email protected]> Reviewed-by: Alex Deucher <[email protected]> Signed-off-by: Luis Henriques <[email protected]> --- drivers/gpu/drm/radeon/radeon_irq_kms.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/gpu/drm/radeon/radeon_irq_kms.c b/drivers/gpu/drm/radeon/radeon_irq_kms.c index 16807afab362..c74f12d125f7 100644 --- a/drivers/gpu/drm/radeon/radeon_irq_kms.c +++ b/drivers/gpu/drm/radeon/radeon_irq_kms.c @@ -202,6 +202,16 @@ static bool radeon_msi_ok(struct radeon_device *rdev) if (rdev->flags & RADEON_IS_AGP) return false; + /* + * Older chips have a HW limitation, they can only generate 40 bits + * of address for "64-bit" MSIs which breaks on some platforms, notably + * IBM POWER servers, so we limit them + */ + if (rdev->family < CHIP_BONAIRE) { + dev_info(rdev->dev, "radeon: MSI limited to 32-bit\n"); + rdev->pdev->no_64bit_msi = 1; + } + /* force MSI on */ if (radeon_msi == 1) return true; -- 2.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/

