drm/radeon: enable pci bus mastering after card is initialised (v2)

This closes a race seen with kexec where we enable PCI bus mastering
but the card has been reinitialised fully yet.

This was previously fixed by a patch from Jerome, but this should
close the race completely.

v2: add SI support as suggested by Alex.

Reported-and-tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/r100.c

@@ -1180,6 +1180,10 @@ int r100_cp_init(struct radeon_device *rdev, unsigned ring_size)
 	WREG32(RADEON_CP_RB_WPTR_DELAY, 0);
 	WREG32(RADEON_CP_CSQ_MODE, 0x00004D4D);
 	WREG32(RADEON_CP_CSQ_CNTL, RADEON_CSQ_PRIBM_INDBM);
+
+	/* at this point everything should be setup correctly to enable master */
+	pci_set_master(rdev->pdev);
+
 	radeon_ring_start(rdev, RADEON_RING_TYPE_GFX_INDEX, &rdev->ring[RADEON_RING_TYPE_GFX_INDEX]);
 	r = radeon_ring_test(rdev, RADEON_RING_TYPE_GFX_INDEX, ring);
 	if (r) {

drivers/gpu/drm/radeon/r600.c

@@ -3047,6 +3047,9 @@ int r600_irq_init(struct radeon_device *rdev)
 	else
 		r600_disable_interrupt_state(rdev);
 
+	/* at this point everything should be setup correctly to enable master */
+	pci_set_master(rdev->pdev);
+
 	/* enable irqs */
 	r600_enable_interrupts(rdev);
 

drivers/gpu/drm/radeon/radeon_device.c

@@ -955,7 +955,6 @@ int radeon_resume_kms(struct drm_device *dev)
 		console_unlock();
 		return -1;
 	}
-	pci_set_master(dev->pdev);
 	/* resume AGP if in use */
 	radeon_agp_resume(rdev);
 	radeon_resume(rdev);

drivers/gpu/drm/radeon/radeon_kms.c

@@ -57,8 +57,6 @@ int radeon_driver_load_kms(struct drm_device *dev, unsigned long flags)
 	}
 	dev->dev_private = (void *)rdev;
 
-	pci_set_master(dev->pdev);
-
 	/* update BUS flag */
 	if (drm_pci_device_is_agp(dev)) {
 		flags |= RADEON_IS_AGP;

drivers/gpu/drm/radeon/si.c

@@ -3217,6 +3217,8 @@ static int si_irq_init(struct radeon_device *rdev)
 	/* force the active interrupt state to all disabled */
 	si_disable_interrupt_state(rdev);
 
+	pci_set_master(rdev->pdev);
+
 	/* enable irqs */
 	si_enable_interrupts(rdev);