From 0bd252de78d406485c896508c13a8f7a78ee8353 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Wed, 27 Aug 2014 13:01:35 -0600 Subject: [PATCH] radeon: Test for PCI root bus before assuming bus->self If we assign a Radeon device to a virtual machine, we can no longer assume a fixed hardware topology, like the GPU having a parent device. This patch simply adds a few pci_is_root_bus() tests to avoid passing a NULL pointer to PCI access functions, allowing the radeon driver to work in a QEMU 440FX machine with an assigned HD8570 on the emulated PCI root bus. Signed-off-by: Alex Williamson Signed-off-by: Alex Deucher --- drivers/gpu/drm/radeon/cik.c | 6 +++++- drivers/gpu/drm/radeon/si.c | 6 +++++- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/radeon/cik.c b/drivers/gpu/drm/radeon/cik.c index e57698847be5..fa9565957f9d 100644 --- a/drivers/gpu/drm/radeon/cik.c +++ b/drivers/gpu/drm/radeon/cik.c @@ -9563,6 +9563,9 @@ static void cik_pcie_gen3_enable(struct radeon_device *rdev) int ret, i; u16 tmp16; + if (pci_is_root_bus(rdev->pdev->bus)) + return; + if (radeon_pcie_gen2 == 0) return; @@ -9789,7 +9792,8 @@ static void cik_program_aspm(struct radeon_device *rdev) if (orig != data) WREG32_PCIE_PORT(PCIE_LC_LINK_WIDTH_CNTL, data); - if (!disable_clkreq) { + if (!disable_clkreq && + !pci_is_root_bus(rdev->pdev->bus)) { struct pci_dev *root = rdev->pdev->bus->self; u32 lnkcap; diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c index 739e0a5349f8..6bce40847753 100644 --- a/drivers/gpu/drm/radeon/si.c +++ b/drivers/gpu/drm/radeon/si.c @@ -7188,6 +7188,9 @@ static void si_pcie_gen3_enable(struct radeon_device *rdev) int ret, i; u16 tmp16; + if (pci_is_root_bus(rdev->pdev->bus)) + return; + if (radeon_pcie_gen2 == 0) return; @@ -7465,7 +7468,8 @@ static void si_program_aspm(struct radeon_device *rdev) if (orig != data) WREG32_PIF_PHY1(PB1_PIF_CNTL, data); - if (!disable_clkreq) { + if (!disable_clkreq && + !pci_is_root_bus(rdev->pdev->bus)) { struct pci_dev *root = rdev->pdev->bus->self; u32 lnkcap; -- GitLab