diff options
Diffstat (limited to 'drivers/gpu/vga/vgaarb.c')
| -rw-r--r-- | drivers/gpu/vga/vgaarb.c | 113 |
1 files changed, 99 insertions, 14 deletions
diff --git a/drivers/gpu/vga/vgaarb.c b/drivers/gpu/vga/vgaarb.c index be8d4cb5861c..8a1021f2e319 100644 --- a/drivers/gpu/vga/vgaarb.c +++ b/drivers/gpu/vga/vgaarb.c @@ -61,7 +61,7 @@ struct vga_device { unsigned int mem_lock_cnt; /* legacy MEM lock count */ unsigned int io_norm_cnt; /* normal IO count */ unsigned int mem_norm_cnt; /* normal MEM count */ - + bool bridge_has_one_vga; /* allow IRQ enable/disable hook */ void *cookie; void (*irq_set_state)(void *cookie, bool enable); @@ -165,6 +165,8 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev, unsigned int wants, legacy_wants, match; struct vga_device *conflict; unsigned int pci_bits; + u32 flags = 0; + /* Account for "normal" resources to lock. If we decode the legacy, * counterpart, we need to request it as well */ @@ -237,16 +239,23 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev, /* looks like he doesn't have a lock, we can steal * them from him */ - vga_irq_set_state(conflict, false); + flags = 0; pci_bits = 0; - if (lwants & (VGA_RSRC_LEGACY_MEM|VGA_RSRC_NORMAL_MEM)) - pci_bits |= PCI_COMMAND_MEMORY; - if (lwants & (VGA_RSRC_LEGACY_IO|VGA_RSRC_NORMAL_IO)) - pci_bits |= PCI_COMMAND_IO; - pci_set_vga_state(conflict->pdev, false, pci_bits, - change_bridge); + if (!conflict->bridge_has_one_vga) { + vga_irq_set_state(conflict, false); + flags |= PCI_VGA_STATE_CHANGE_DECODES; + if (lwants & (VGA_RSRC_LEGACY_MEM|VGA_RSRC_NORMAL_MEM)) + pci_bits |= PCI_COMMAND_MEMORY; + if (lwants & (VGA_RSRC_LEGACY_IO|VGA_RSRC_NORMAL_IO)) + pci_bits |= PCI_COMMAND_IO; + } + + if (change_bridge) + flags |= PCI_VGA_STATE_CHANGE_BRIDGE; + + pci_set_vga_state(conflict->pdev, false, pci_bits, flags); conflict->owns &= ~lwants; /* If he also owned non-legacy, that is no longer the case */ if (lwants & VGA_RSRC_LEGACY_MEM) @@ -261,14 +270,24 @@ enable_them: * also have in "decodes". We can lock resources we don't decode but * not own them. */ + flags = 0; pci_bits = 0; - if (wants & (VGA_RSRC_LEGACY_MEM|VGA_RSRC_NORMAL_MEM)) - pci_bits |= PCI_COMMAND_MEMORY; - if (wants & (VGA_RSRC_LEGACY_IO|VGA_RSRC_NORMAL_IO)) - pci_bits |= PCI_COMMAND_IO; - pci_set_vga_state(vgadev->pdev, true, pci_bits, !!(wants & VGA_RSRC_LEGACY_MASK)); - vga_irq_set_state(vgadev, true); + if (!vgadev->bridge_has_one_vga) { + flags |= PCI_VGA_STATE_CHANGE_DECODES; + if (wants & (VGA_RSRC_LEGACY_MEM|VGA_RSRC_NORMAL_MEM)) + pci_bits |= PCI_COMMAND_MEMORY; + if (wants & (VGA_RSRC_LEGACY_IO|VGA_RSRC_NORMAL_IO)) + pci_bits |= PCI_COMMAND_IO; + } + if (!!(wants & VGA_RSRC_LEGACY_MASK)) + flags |= PCI_VGA_STATE_CHANGE_BRIDGE; + + pci_set_vga_state(vgadev->pdev, true, pci_bits, flags); + + if (!vgadev->bridge_has_one_vga) { + vga_irq_set_state(vgadev, true); + } vgadev->owns |= (wants & vgadev->decodes); lock_them: vgadev->locks |= (rsrc & VGA_RSRC_LEGACY_MASK); @@ -421,6 +440,62 @@ bail: } EXPORT_SYMBOL(vga_put); +/* Rules for using a bridge to control a VGA descendant decoding: + if a bridge has only one VGA descendant then it can be used + to control the VGA routing for that device. + It should always use the bridge closest to the device to control it. + If a bridge has a direct VGA descendant, but also have a sub-bridge + VGA descendant then we cannot use that bridge to control the direct VGA descendant. + So for every device we register, we need to iterate all its parent bridges + so we can invalidate any devices using them properly. +*/ +static void vga_arbiter_check_bridge_sharing(struct vga_device *vgadev) +{ + struct vga_device *same_bridge_vgadev; + struct pci_bus *new_bus, *bus; + struct pci_dev *new_bridge, *bridge; + + vgadev->bridge_has_one_vga = true; + + if (list_empty(&vga_list)) + return; + + /* okay iterate the new devices bridge hierarachy */ + new_bus = vgadev->pdev->bus; + while (new_bus) { + new_bridge = new_bus->self; + + if (new_bridge) { + /* go through list of devices already registered */ + list_for_each_entry(same_bridge_vgadev, &vga_list, list) { + bus = same_bridge_vgadev->pdev->bus; + bridge = bus->self; + + /* see if the share a bridge with this device */ + if (new_bridge == bridge) { + /* if their direct parent bridge is the same + as any bridge of this device then it can't be used + for that device */ + same_bridge_vgadev->bridge_has_one_vga = false; + } + + /* now iterate the previous devices bridge hierarchy */ + /* if the new devices parent bridge is in the other devices + hierarchy then we can't use it to control this device */ + while (bus) { + bridge = bus->self; + if (bridge) { + if (bridge == vgadev->pdev->bus->self) + vgadev->bridge_has_one_vga = false; + } + bus = bus->parent; + } + } + } + new_bus = new_bus->parent; + } +} + /* * Currently, we assume that the "initial" setup of the system is * not sane, that is we come up with conflicting devices and let @@ -500,6 +575,8 @@ static bool vga_arbiter_add_pci_device(struct pci_dev *pdev) vga_default = pci_dev_get(pdev); #endif + vga_arbiter_check_bridge_sharing(vgadev); + /* Add to the list */ list_add(&vgadev->list, &vga_list); vga_count++; @@ -1222,6 +1299,7 @@ static int __init vga_arb_device_init(void) { int rc; struct pci_dev *pdev; + struct vga_device *vgadev; rc = misc_register(&vga_arb_device); if (rc < 0) @@ -1238,6 +1316,13 @@ static int __init vga_arb_device_init(void) vga_arbiter_add_pci_device(pdev); pr_info("vgaarb: loaded\n"); + + list_for_each_entry(vgadev, &vga_list, list) { + if (vgadev->bridge_has_one_vga) + pr_info("vgaarb: bridge control possible %s\n", pci_name(vgadev->pdev)); + else + pr_info("vgaarb: no bridge control possible %s\n", pci_name(vgadev->pdev)); + } return rc; } subsys_initcall(vga_arb_device_init); |