From 05082b8bbd1a0ffc74235449c4b8930a8c240f85 Mon Sep 17 00:00:00 2001 From: Alex Deucher Date: Mon, 13 Jun 2016 15:37:34 -0400 Subject: [PATCH] drm/radeon: fix asic initialization for virtualized environments When executing in a PCI passthrough based virtuzliation environment, the hypervisor will usually attempt to send a PCIe bus reset signal to the ASIC when the VM reboots. In this scenario, the card is not correctly initialized, but we still consider it to be posted. Therefore, in a passthrough based environemnt we should always post the card to guarantee it is in a good state for driver initialization. Ported from amdgpu commit: amdgpu: fix asic initialization for virtualized environments Cc: Andres Rodriguez Cc: Alex Williamson Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org --- drivers/gpu/drm/radeon/radeon_device.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c index e61c7636864d..21c44b2293bc 100644 --- a/drivers/gpu/drm/radeon/radeon_device.c +++ b/drivers/gpu/drm/radeon/radeon_device.c @@ -630,6 +630,23 @@ void radeon_gtt_location(struct radeon_device *rdev, struct radeon_mc *mc) /* * GPU helpers function. */ + +/** + * radeon_device_is_virtual - check if we are running is a virtual environment + * + * Check if the asic has been passed through to a VM (all asics). + * Used at driver startup. + * Returns true if virtual or false if not. + */ +static bool radeon_device_is_virtual(void) +{ +#ifdef CONFIG_X86 + return boot_cpu_has(X86_FEATURE_HYPERVISOR); +#else + return false; +#endif +} + /** * radeon_card_posted - check if the hw has already been initialized * @@ -643,6 +660,10 @@ bool radeon_card_posted(struct radeon_device *rdev) { uint32_t reg; + /* for pass through, always force asic_init */ + if (radeon_device_is_virtual()) + return false; + /* required for EFI mode on macbook2,1 which uses an r5xx asic */ if (efi_enabled(EFI_BOOT) && (rdev->pdev->subsystem_vendor == PCI_VENDOR_ID_APPLE) && -- 2.20.1