diff options
Diffstat (limited to 'drivers/gpu/vga/vgaarb.c')
| -rw-r--r-- | drivers/gpu/vga/vgaarb.c | 40 |
1 files changed, 22 insertions, 18 deletions
diff --git a/drivers/gpu/vga/vgaarb.c b/drivers/gpu/vga/vgaarb.c index af0259708358..d2077f040f3e 100644 --- a/drivers/gpu/vga/vgaarb.c +++ b/drivers/gpu/vga/vgaarb.c @@ -237,12 +237,10 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev, if (conflict->locks & lwants) return conflict; - /* Ok, now check if he owns the resource we want. We don't need - * to check "decodes" since it should be impossible to own - * own legacy resources you don't decode unless I have a bug - * in this code... + /* Ok, now check if it owns the resource we want. We can + * lock resources that are not decoded, therefore a device + * can own resources it doesn't decode. */ - WARN_ON(conflict->owns & ~conflict->decodes); match = lwants & conflict->owns; if (!match) continue; @@ -254,13 +252,19 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev, flags = 0; pci_bits = 0; + /* If we can't control legacy resources via the bridge, we + * also need to disable normal decoding. + */ if (!conflict->bridge_has_one_vga) { - vga_irq_set_state(conflict, false); - flags |= PCI_VGA_STATE_CHANGE_DECODES; - if (match & (VGA_RSRC_LEGACY_MEM|VGA_RSRC_NORMAL_MEM)) + if ((match & conflict->decodes) & VGA_RSRC_LEGACY_MEM) pci_bits |= PCI_COMMAND_MEMORY; - if (match & (VGA_RSRC_LEGACY_IO|VGA_RSRC_NORMAL_IO)) + if ((match & conflict->decodes) & VGA_RSRC_LEGACY_IO) pci_bits |= PCI_COMMAND_IO; + + if (pci_bits) { + vga_irq_set_state(conflict, false); + flags |= PCI_VGA_STATE_CHANGE_DECODES; + } } if (change_bridge) @@ -268,18 +272,19 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev, pci_set_vga_state(conflict->pdev, false, pci_bits, flags); conflict->owns &= ~match; - /* If he also owned non-legacy, that is no longer the case */ - if (match & VGA_RSRC_LEGACY_MEM) + + /* If we disabled normal decoding, reflect it in owns */ + if (pci_bits & PCI_COMMAND_MEMORY) conflict->owns &= ~VGA_RSRC_NORMAL_MEM; - if (match & VGA_RSRC_LEGACY_IO) + if (pci_bits & PCI_COMMAND_IO) conflict->owns &= ~VGA_RSRC_NORMAL_IO; } enable_them: /* ok dude, we got it, everybody conflicting has been disabled, let's - * enable us. Make sure we don't mark a bit in "owns" that we don't - * also have in "decodes". We can lock resources we don't decode but - * not own them. + * enable us. Mark any bits in "owns" regardless of whether we + * decoded them. We can lock resources we don't decode, therefore + * we must track them via "owns". */ flags = 0; pci_bits = 0; @@ -291,7 +296,7 @@ enable_them: if (wants & (VGA_RSRC_LEGACY_IO|VGA_RSRC_NORMAL_IO)) pci_bits |= PCI_COMMAND_IO; } - if (!!(wants & VGA_RSRC_LEGACY_MASK)) + if (wants & VGA_RSRC_LEGACY_MASK) flags |= PCI_VGA_STATE_CHANGE_BRIDGE; pci_set_vga_state(vgadev->pdev, true, pci_bits, flags); @@ -299,7 +304,7 @@ enable_them: if (!vgadev->bridge_has_one_vga) { vga_irq_set_state(vgadev, true); } - vgadev->owns |= (wants & vgadev->decodes); + vgadev->owns |= wants; lock_them: vgadev->locks |= (rsrc & VGA_RSRC_LEGACY_MASK); if (rsrc & VGA_RSRC_LEGACY_IO) @@ -649,7 +654,6 @@ static inline void vga_update_device_decodes(struct vga_device *vgadev, old_decodes = vgadev->decodes; decodes_removed = ~new_decodes & old_decodes; decodes_unlocked = vgadev->locks & decodes_removed; - vgadev->owns &= ~decodes_removed; vgadev->decodes = new_decodes; pr_info("vgaarb: device changed decodes: PCI:%s,olddecodes=%s,decodes=%s:owns=%s\n", |