Diffstat (limited to 'include/linux')
2 files changed, 197 insertions, 0 deletions
diff --git a/include/linux/pci.h b/include/linux/pci.h
index a90f94020798..6dbb1fd30e5a 100644
@@ -806,6 +806,8 @@ int pci_cfg_space_size_ext(struct pci_dev *dev);
int pci_cfg_space_size(struct pci_dev *dev);
unsigned char pci_bus_max_busnr(struct pci_bus *bus);
+int pci_set_vga_state(struct pci_dev *pdev, bool decode,
+ unsigned int command_bits, bool change_bridge);
/* kmem_cache style wrapper around pci_alloc_consistent() */
diff --git a/include/linux/vgaarb.h b/include/linux/vgaarb.h
new file mode 100644
@@ -0,0 +1,195 @@
+ * vgaarb.c
+ * (C) Copyright 2005 Benjamin Herrenschmidt <firstname.lastname@example.org>
+ * (C) Copyright 2007 Paulo R. Zanoni <email@example.com>
+ * (C) Copyright 2007, 2009 Tiago Vignatti <firstname.lastname@example.org>
+/* Legacy VGA regions */
+#define VGA_RSRC_NONE 0x00
+#define VGA_RSRC_LEGACY_IO 0x01
+#define VGA_RSRC_LEGACY_MEM 0x02
+#define VGA_RSRC_LEGACY_MASK (VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM)
+/* Non-legacy access */
+#define VGA_RSRC_NORMAL_IO 0x04
+#define VGA_RSRC_NORMAL_MEM 0x08
+/* Passing that instead of a pci_dev to use the system "default"
+ * device, that is the one used by vgacon. Archs will probably
+ * have to provide their own vga_default_device();
+#define VGA_DEFAULT_DEVICE (NULL)
+/* For use by clients */
+ * vga_set_legacy_decoding
+ * @pdev: pci device of the VGA card
+ * @decodes: bit mask of what legacy regions the card decodes
+ * Indicates to the arbiter if the card decodes legacy VGA IOs,
+ * legacy VGA Memory, both, or none. All cards default to both,
+ * the card driver (fbdev for example) should tell the arbiter
+ * if it has disabled legacy decoding, so the card can be left
+ * out of the arbitration process (and can be safe to take
+ * interrupts at any time.
+extern void vga_set_legacy_decoding(struct pci_dev *pdev,
+ unsigned int decodes);
+ * vga_get - acquire & locks VGA resources
+ * pdev: pci device of the VGA card or NULL for the system default
+ * rsrc: bit mask of resources to acquire and lock
+ * interruptible: blocking should be interruptible by signals ?
+ * This function acquires VGA resources for the given
+ * card and mark those resources locked. If the resource requested
+ * are "normal" (and not legacy) resources, the arbiter will first check
+ * wether the card is doing legacy decoding for that type of resource. If
+ * yes, the lock is "converted" into a legacy resource lock.
+ * The arbiter will first look for all VGA cards that might conflict
+ * and disable their IOs and/or Memory access, inlcuding VGA forwarding
+ * on P2P bridges if necessary, so that the requested resources can
+ * be used. Then, the card is marked as locking these resources and
+ * the IO and/or Memory accesse are enabled on the card (including
+ * VGA forwarding on parent P2P bridges if any).
+ * This function will block if some conflicting card is already locking
+ * one of the required resources (or any resource on a different bus
+ * segment, since P2P bridges don't differenciate VGA memory and IO
+ * afaik). You can indicate wether this blocking should be interruptible
+ * by a signal (for userland interface) or not.
+ * Must not be called at interrupt time or in atomic context.
+ * If the card already owns the resources, the function succeeds.
+ * Nested calls are supported (a per-resource counter is maintained)
+extern int vga_get(struct pci_dev *pdev, unsigned int rsrc,
+ int interruptible);
+ * vga_get_interruptible
+ * Shortcut to vga_get
+static inline int vga_get_interruptible(struct pci_dev *pdev,
+ unsigned int rsrc)
+ return vga_get(pdev, rsrc, 1);
+ * vga_get_interruptible
+ * Shortcut to vga_get
+static inline int vga_get_uninterruptible(struct pci_dev *pdev,
+ unsigned int rsrc)
+ return vga_get(pdev, rsrc, 0);
+ * vga_tryget - try to acquire & lock legacy VGA resources
+ * @pdev: pci devivce of VGA card or NULL for system default
+ * @rsrc: bit mask of resources to acquire and lock
+ * This function performs the same operation as vga_get(), but
+ * will return an error (-EBUSY) instead of blocking if the resources
+ * are already locked by another card. It can be called in any context
+extern int vga_tryget(struct pci_dev *pdev, unsigned int rsrc);
+ * vga_put - release lock on legacy VGA resources
+ * @pdev: pci device of VGA card or NULL for system default
+ * @rsrc: but mask of resource to release
+ * This function releases resources previously locked by vga_get()
+ * or vga_tryget(). The resources aren't disabled right away, so
+ * that a subsequence vga_get() on the same card will succeed
+ * immediately. Resources have a counter, so locks are only
+ * released if the counter reaches 0.
+extern void vga_put(struct pci_dev *pdev, unsigned int rsrc);
+ * vga_default_device
+ * This can be defined by the platform. The default implementation
+ * is rather dumb and will probably only work properly on single
+ * vga card setups and/or x86 platforms.
+ * If your VGA default device is not PCI, you'll have to return
+ * NULL here. In this case, I assume it will not conflict with
+ * any PCI card. If this is not true, I'll have to define two archs
+ * hooks for enabling/disabling the VGA default device if that is
+ * possible. This may be a problem with real _ISA_ VGA cards, in
+ * addition to a PCI one. I don't know at this point how to deal
+ * with that card. Can theirs IOs be disabled at all ? If not, then
+ * I suppose it's a matter of having the proper arch hook telling
+ * us about it, so we basically never allow anybody to succeed a
+ * vga_get()...
+extern struct pci_dev *vga_default_device(void);
+ * vga_conflicts
+ * Architectures should define this if they have several
+ * independant PCI domains that can afford concurrent VGA
+ * decoding
+static inline int vga_conflicts(struct pci_dev *p1, struct pci_dev *p2)
+ return 1;
+ * Register a client with the VGA arbitration logic
+ * return value: number of VGA devices in system.
+ * Clients have two callback mechanisms they can use.
+ * irq enable/disable callback -
+ * If a client can't disable its GPUs VGA resources, then we
+ * need to be able to ask it to turn off its irqs when we
+ * turn off its mem and io decoding.
+ * set_vga_decode
+ * If a client can disable its GPU VGA resource, it will
+ * get a callback from this to set the encode/decode state
+ * Clients with disable abilities should check the return value
+ * of this function and if the VGA device count is > 1, should
+ * disable VGA decoding resources.
+ * Rationale: we cannot disable VGA decode resources unconditionally
+ * some single GPU laptops seem to require ACPI or BIOS access to the
+ * VGA registers to control things like backlights etc.
+ * Hopefully newer multi-GPU laptops do something saner, and desktops
+ * won't have any special ACPI for this.
+int vga_client_register(struct pci_dev *pdev, void *cookie,
+ void (*irq_set_state)(void *cookie, bool state),
+ unsigned int (*set_vga_decode)(void *cookie, bool state));
+#endif /* LINUX_VGA_H */