diff options
Diffstat (limited to 'drivers/gpu/vga')
| -rw-r--r-- | drivers/gpu/vga/Kconfig | 19 | ||||
| -rw-r--r-- | drivers/gpu/vga/Makefile | 1 | ||||
| -rw-r--r-- | drivers/gpu/vga/vgaarb.c | 1567 |
3 files changed, 0 insertions, 1587 deletions
diff --git a/drivers/gpu/vga/Kconfig b/drivers/gpu/vga/Kconfig index 1ad4c4ef0b5e..eb8b14ab22c3 100644 --- a/drivers/gpu/vga/Kconfig +++ b/drivers/gpu/vga/Kconfig @@ -1,23 +1,4 @@ # SPDX-License-Identifier: GPL-2.0-only -config VGA_ARB - bool "VGA Arbitration" if EXPERT - default y - depends on (PCI && !S390) - help - Some "legacy" VGA devices implemented on PCI typically have the same - hard-decoded addresses as they did on ISA. When multiple PCI devices - are accessed at same time they need some kind of coordination. Please - see Documentation/gpu/vgaarbiter.rst for more details. Select this to - enable VGA arbiter. - -config VGA_ARB_MAX_GPUS - int "Maximum number of GPUs" - default 16 - depends on VGA_ARB - help - Reserves space in the kernel to maintain resource locking for - multiple GPUS. The overhead for each GPU is very small. - config VGA_SWITCHEROO bool "Laptop Hybrid Graphics - GPU switching support" depends on X86 diff --git a/drivers/gpu/vga/Makefile b/drivers/gpu/vga/Makefile index e92064442d60..9800620deda3 100644 --- a/drivers/gpu/vga/Makefile +++ b/drivers/gpu/vga/Makefile @@ -1,3 +1,2 @@ # SPDX-License-Identifier: GPL-2.0-only -obj-$(CONFIG_VGA_ARB) += vgaarb.o obj-$(CONFIG_VGA_SWITCHEROO) += vga_switcheroo.o diff --git a/drivers/gpu/vga/vgaarb.c b/drivers/gpu/vga/vgaarb.c deleted file mode 100644 index 569930552957..000000000000 --- a/drivers/gpu/vga/vgaarb.c +++ /dev/null @@ -1,1567 +0,0 @@ -/* - * vgaarb.c: Implements the VGA arbitration. For details refer to - * Documentation/gpu/vgaarbiter.rst - * - * - * (C) Copyright 2005 Benjamin Herrenschmidt <benh@kernel.crashing.org> - * (C) Copyright 2007 Paulo R. Zanoni <przanoni@gmail.com> - * (C) Copyright 2007, 2009 Tiago Vignatti <vignatti@freedesktop.org> - * - * Permission is hereby granted, free of charge, to any person obtaining a - * copy of this software and associated documentation files (the "Software"), - * to deal in the Software without restriction, including without limitation - * the rights to use, copy, modify, merge, publish, distribute, sublicense, - * and/or sell copies of the Software, and to permit persons to whom the - * Software is furnished to do so, subject to the following conditions: - * - * The above copyright notice and this permission notice (including the next - * paragraph) shall be included in all copies or substantial portions of the - * Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL - * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING - * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER - * DEALINGS - * IN THE SOFTWARE. - * - */ - -#define pr_fmt(fmt) "vgaarb: " fmt - -#define vgaarb_dbg(dev, fmt, arg...) dev_dbg(dev, "vgaarb: " fmt, ##arg) -#define vgaarb_info(dev, fmt, arg...) dev_info(dev, "vgaarb: " fmt, ##arg) -#define vgaarb_err(dev, fmt, arg...) dev_err(dev, "vgaarb: " fmt, ##arg) - -#include <linux/module.h> -#include <linux/kernel.h> -#include <linux/pci.h> -#include <linux/errno.h> -#include <linux/init.h> -#include <linux/list.h> -#include <linux/sched/signal.h> -#include <linux/wait.h> -#include <linux/spinlock.h> -#include <linux/poll.h> -#include <linux/miscdevice.h> -#include <linux/slab.h> -#include <linux/screen_info.h> -#include <linux/vt.h> -#include <linux/console.h> -#include <linux/acpi.h> - -#include <linux/uaccess.h> - -#include <linux/vgaarb.h> - -static void vga_arbiter_notify_clients(void); -/* - * We keep a list of all vga devices in the system to speed - * up the various operations of the arbiter - */ -struct vga_device { - struct list_head list; - struct pci_dev *pdev; - unsigned int decodes; /* what does it decodes */ - unsigned int owns; /* what does it owns */ - unsigned int locks; /* what does it locks */ - unsigned int io_lock_cnt; /* legacy IO lock count */ - 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; - unsigned int (*set_decode)(struct pci_dev *pdev, bool decode); -}; - -static LIST_HEAD(vga_list); -static int vga_count, vga_decode_count; -static bool vga_arbiter_used; -static DEFINE_SPINLOCK(vga_lock); -static DECLARE_WAIT_QUEUE_HEAD(vga_wait_queue); - - -static const char *vga_iostate_to_str(unsigned int iostate) -{ - /* Ignore VGA_RSRC_IO and VGA_RSRC_MEM */ - iostate &= VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; - switch (iostate) { - case VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM: - return "io+mem"; - case VGA_RSRC_LEGACY_IO: - return "io"; - case VGA_RSRC_LEGACY_MEM: - return "mem"; - } - return "none"; -} - -static int vga_str_to_iostate(char *buf, int str_size, int *io_state) -{ - /* we could in theory hand out locks on IO and mem - * separately to userspace but it can cause deadlocks */ - if (strncmp(buf, "none", 4) == 0) { - *io_state = VGA_RSRC_NONE; - return 1; - } - - /* XXX We're not chekcing the str_size! */ - if (strncmp(buf, "io+mem", 6) == 0) - goto both; - else if (strncmp(buf, "io", 2) == 0) - goto both; - else if (strncmp(buf, "mem", 3) == 0) - goto both; - return 0; -both: - *io_state = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; - return 1; -} - -/* this is only used a cookie - it should not be dereferenced */ -static struct pci_dev *vga_default; - -static void vga_arb_device_card_gone(struct pci_dev *pdev); - -/* Find somebody in our list */ -static struct vga_device *vgadev_find(struct pci_dev *pdev) -{ - struct vga_device *vgadev; - - list_for_each_entry(vgadev, &vga_list, list) - if (pdev == vgadev->pdev) - return vgadev; - return NULL; -} - -/** - * vga_default_device - return the default VGA device, for vgacon - * - * 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()... - */ -struct pci_dev *vga_default_device(void) -{ - return vga_default; -} -EXPORT_SYMBOL_GPL(vga_default_device); - -void vga_set_default_device(struct pci_dev *pdev) -{ - if (vga_default == pdev) - return; - - pci_dev_put(vga_default); - vga_default = pci_dev_get(pdev); -} - -/** - * vga_remove_vgacon - deactivete vga console - * - * Unbind and unregister vgacon in case pdev is the default vga - * device. Can be called by gpu drivers on initialization to make - * sure vga register access done by vgacon will not disturb the - * device. - * - * @pdev: pci device. - */ -#if !defined(CONFIG_VGA_CONSOLE) -int vga_remove_vgacon(struct pci_dev *pdev) -{ - return 0; -} -#elif !defined(CONFIG_DUMMY_CONSOLE) -int vga_remove_vgacon(struct pci_dev *pdev) -{ - return -ENODEV; -} -#else -int vga_remove_vgacon(struct pci_dev *pdev) -{ - int ret = 0; - - if (pdev != vga_default) - return 0; - vgaarb_info(&pdev->dev, "deactivate vga console\n"); - - console_lock(); - if (con_is_bound(&vga_con)) - ret = do_take_over_console(&dummy_con, 0, - MAX_NR_CONSOLES - 1, 1); - if (ret == 0) { - ret = do_unregister_con_driver(&vga_con); - - /* Ignore "already unregistered". */ - if (ret == -ENODEV) - ret = 0; - } - console_unlock(); - - return ret; -} -#endif -EXPORT_SYMBOL(vga_remove_vgacon); - -/* If we don't ever use VGA arb we should avoid - turning off anything anywhere due to old X servers getting - confused about the boot device not being VGA */ -static void vga_check_first_use(void) -{ - /* we should inform all GPUs in the system that - * VGA arb has occurred and to try and disable resources - * if they can */ - if (!vga_arbiter_used) { - vga_arbiter_used = true; - vga_arbiter_notify_clients(); - } -} - -static struct vga_device *__vga_tryget(struct vga_device *vgadev, - unsigned int rsrc) -{ - struct device *dev = &vgadev->pdev->dev; - 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 - */ - if ((rsrc & VGA_RSRC_NORMAL_IO) && - (vgadev->decodes & VGA_RSRC_LEGACY_IO)) - rsrc |= VGA_RSRC_LEGACY_IO; - if ((rsrc & VGA_RSRC_NORMAL_MEM) && - (vgadev->decodes & VGA_RSRC_LEGACY_MEM)) - rsrc |= VGA_RSRC_LEGACY_MEM; - - vgaarb_dbg(dev, "%s: %d\n", __func__, rsrc); - vgaarb_dbg(dev, "%s: owns: %d\n", __func__, vgadev->owns); - - /* Check what resources we need to acquire */ - wants = rsrc & ~vgadev->owns; - - /* We already own everything, just mark locked & bye bye */ - if (wants == 0) - goto lock_them; - - /* We don't need to request a legacy resource, we just enable - * appropriate decoding and go - */ - legacy_wants = wants & VGA_RSRC_LEGACY_MASK; - if (legacy_wants == 0) - goto enable_them; - - /* Ok, we don't, let's find out how we need to kick off */ - list_for_each_entry(conflict, &vga_list, list) { - unsigned int lwants = legacy_wants; - unsigned int change_bridge = 0; - - /* Don't conflict with myself */ - if (vgadev == conflict) - continue; - - /* We have a possible conflict. before we go further, we must - * check if we sit on the same bus as the conflicting device. - * if we don't, then we must tie both IO and MEM resources - * together since there is only a single bit controlling - * VGA forwarding on P2P bridges - */ - if (vgadev->pdev->bus != conflict->pdev->bus) { - change_bridge = 1; - lwants = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; - } - - /* Check if the guy has a lock on the resource. If he does, - * return the conflicting entry - */ - if (conflict->locks & lwants) - return conflict; - - /* 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. - */ - match = lwants & conflict->owns; - if (!match) - continue; - - /* looks like he doesn't have a lock, we can steal - * them from him - */ - - 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) { - if ((match & conflict->decodes) & VGA_RSRC_LEGACY_MEM) - pci_bits |= PCI_COMMAND_MEMORY; - if ((match & conflict->decodes) & VGA_RSRC_LEGACY_IO) - pci_bits |= PCI_COMMAND_IO; - - if (pci_bits) - flags |= PCI_VGA_STATE_CHANGE_DECODES; - } - - if (change_bridge) - flags |= PCI_VGA_STATE_CHANGE_BRIDGE; - - pci_set_vga_state(conflict->pdev, false, pci_bits, flags); - conflict->owns &= ~match; - - /* If we disabled normal decoding, reflect it in owns */ - if (pci_bits & PCI_COMMAND_MEMORY) - conflict->owns &= ~VGA_RSRC_NORMAL_MEM; - 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. 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; - - 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); - - vgadev->owns |= wants; -lock_them: - vgadev->locks |= (rsrc & VGA_RSRC_LEGACY_MASK); - if (rsrc & VGA_RSRC_LEGACY_IO) - vgadev->io_lock_cnt++; - if (rsrc & VGA_RSRC_LEGACY_MEM) - vgadev->mem_lock_cnt++; - if (rsrc & VGA_RSRC_NORMAL_IO) - vgadev->io_norm_cnt++; - if (rsrc & VGA_RSRC_NORMAL_MEM) - vgadev->mem_norm_cnt++; - - return NULL; -} - -static void __vga_put(struct vga_device *vgadev, unsigned int rsrc) -{ - struct device *dev = &vgadev->pdev->dev; - unsigned int old_locks = vgadev->locks; - - vgaarb_dbg(dev, "%s\n", __func__); - - /* Update our counters, and account for equivalent legacy resources - * if we decode them - */ - if ((rsrc & VGA_RSRC_NORMAL_IO) && vgadev->io_norm_cnt > 0) { - vgadev->io_norm_cnt--; - if (vgadev->decodes & VGA_RSRC_LEGACY_IO) - rsrc |= VGA_RSRC_LEGACY_IO; - } - if ((rsrc & VGA_RSRC_NORMAL_MEM) && vgadev->mem_norm_cnt > 0) { - vgadev->mem_norm_cnt--; - if (vgadev->decodes & VGA_RSRC_LEGACY_MEM) - rsrc |= VGA_RSRC_LEGACY_MEM; - } - if ((rsrc & VGA_RSRC_LEGACY_IO) && vgadev->io_lock_cnt > 0) - vgadev->io_lock_cnt--; - if ((rsrc & VGA_RSRC_LEGACY_MEM) && vgadev->mem_lock_cnt > 0) - vgadev->mem_lock_cnt--; - - /* Just clear lock bits, we do lazy operations so we don't really - * have to bother about anything else at this point - */ - if (vgadev->io_lock_cnt == 0) - vgadev->locks &= ~VGA_RSRC_LEGACY_IO; - if (vgadev->mem_lock_cnt == 0) - vgadev->locks &= ~VGA_RSRC_LEGACY_MEM; - - /* Kick the wait queue in case somebody was waiting if we actually - * released something - */ - if (old_locks != vgadev->locks) - wake_up_all(&vga_wait_queue); -} - -/** - * 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 whether 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, including 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 accesses 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 differentiate VGA memory and IO afaik). You can indicate - * whether 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) - * - * On success, release the VGA resource again with vga_put(). - * - * Returns: - * - * 0 on success, negative error code on failure. - */ -int vga_get(struct pci_dev *pdev, unsigned int rsrc, int interruptible) -{ - struct vga_device *vgadev, *conflict; - unsigned long flags; - wait_queue_entry_t wait; - int rc = 0; - - vga_check_first_use(); - /* The one who calls us should check for this, but lets be sure... */ - if (pdev == NULL) - pdev = vga_default_device(); - if (pdev == NULL) - return 0; - - for (;;) { - spin_lock_irqsave(&vga_lock, flags); - vgadev = vgadev_find(pdev); - if (vgadev == NULL) { - spin_unlock_irqrestore(&vga_lock, flags); - rc = -ENODEV; - break; - } - conflict = __vga_tryget(vgadev, rsrc); - spin_unlock_irqrestore(&vga_lock, flags); - if (conflict == NULL) - break; - - - /* We have a conflict, we wait until somebody kicks the - * work queue. Currently we have one work queue that we - * kick each time some resources are released, but it would - * be fairly easy to have a per device one so that we only - * need to attach to the conflicting device - */ - init_waitqueue_entry(&wait, current); - add_wait_queue(&vga_wait_queue, &wait); - set_current_state(interruptible ? - TASK_INTERRUPTIBLE : - TASK_UNINTERRUPTIBLE); - if (interruptible && signal_pending(current)) { - __set_current_state(TASK_RUNNING); - remove_wait_queue(&vga_wait_queue, &wait); - rc = -ERESTARTSYS; - break; - } - schedule(); - remove_wait_queue(&vga_wait_queue, &wait); - } - return rc; -} -EXPORT_SYMBOL(vga_get); - -/** - * 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 - * - * On success, release the VGA resource again with vga_put(). - * - * Returns: - * - * 0 on success, negative error code on failure. - */ -static int vga_tryget(struct pci_dev *pdev, unsigned int rsrc) -{ - struct vga_device *vgadev; - unsigned long flags; - int rc = 0; - - vga_check_first_use(); - - /* The one who calls us should check for this, but lets be sure... */ - if (pdev == NULL) - pdev = vga_default_device(); - if (pdev == NULL) - return 0; - spin_lock_irqsave(&vga_lock, flags); - vgadev = vgadev_find(pdev); - if (vgadev == NULL) { - rc = -ENODEV; - goto bail; - } - if (__vga_tryget(vgadev, rsrc)) - rc = -EBUSY; -bail: - spin_unlock_irqrestore(&vga_lock, flags); - return rc; -} - -/** - * 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 fuction 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. - */ -void vga_put(struct pci_dev *pdev, unsigned int rsrc) -{ - struct vga_device *vgadev; - unsigned long flags; - - /* The one who calls us should check for this, but lets be sure... */ - if (pdev == NULL) - pdev = vga_default_device(); - if (pdev == NULL) - return; - spin_lock_irqsave(&vga_lock, flags); - vgadev = vgadev_find(pdev); - if (vgadev == NULL) - goto bail; - __vga_put(vgadev, rsrc); -bail: - spin_unlock_irqrestore(&vga_lock, flags); -} -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; - - /* 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 && 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 - * the arbiter's client decides if devices decodes or not legacy - * things. - */ -static bool vga_arbiter_add_pci_device(struct pci_dev *pdev) -{ - struct vga_device *vgadev; - unsigned long flags; - struct pci_bus *bus; - struct pci_dev *bridge; - u16 cmd; - - /* Only deal with VGA class devices */ - if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA) - return false; - - /* Allocate structure */ - vgadev = kzalloc(sizeof(struct vga_device), GFP_KERNEL); - if (vgadev == NULL) { - vgaarb_err(&pdev->dev, "failed to allocate VGA arbiter data\n"); - /* - * What to do on allocation failure ? For now, let's just do - * nothing, I'm not sure there is anything saner to be done. - */ - return false; - } - - /* Take lock & check for duplicates */ - spin_lock_irqsave(&vga_lock, flags); - if (vgadev_find(pdev) != NULL) { - BUG_ON(1); - goto fail; - } - vgadev->pdev = pdev; - - /* By default, assume we decode everything */ - vgadev->decodes = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM | - VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM; - - /* by default mark it as decoding */ - vga_decode_count++; - /* Mark that we "own" resources based on our enables, we will - * clear that below if the bridge isn't forwarding - */ - pci_read_config_word(pdev, PCI_COMMAND, &cmd); - if (cmd & PCI_COMMAND_IO) - vgadev->owns |= VGA_RSRC_LEGACY_IO; - if (cmd & PCI_COMMAND_MEMORY) - vgadev->owns |= VGA_RSRC_LEGACY_MEM; - - /* Check if VGA cycles can get down to us */ - bus = pdev->bus; - while (bus) { - bridge = bus->self; - if (bridge) { - u16 l; - - pci_read_config_word(bridge, PCI_BRIDGE_CONTROL, &l); - if (!(l & PCI_BRIDGE_CTL_VGA)) { - vgadev->owns = 0; - break; - } - } - bus = bus->parent; - } - - /* Deal with VGA default device. Use first enabled one - * by default if arch doesn't have it's own hook - */ - if (vga_default == NULL && - ((vgadev->owns & VGA_RSRC_LEGACY_MASK) == VGA_RSRC_LEGACY_MASK)) { - vgaarb_info(&pdev->dev, "setting as boot VGA device\n"); - vga_set_default_device(pdev); - } - - vga_arbiter_check_bridge_sharing(vgadev); - - /* Add to the list */ - list_add_tail(&vgadev->list, &vga_list); - vga_count++; - vgaarb_info(&pdev->dev, "VGA device added: decodes=%s,owns=%s,locks=%s\n", - vga_iostate_to_str(vgadev->decodes), - vga_iostate_to_str(vgadev->owns), - vga_iostate_to_str(vgadev->locks)); - - spin_unlock_irqrestore(&vga_lock, flags); - return true; -fail: - spin_unlock_irqrestore(&vga_lock, flags); - kfree(vgadev); - return false; -} - -static bool vga_arbiter_del_pci_device(struct pci_dev *pdev) -{ - struct vga_device *vgadev; - unsigned long flags; - bool ret = true; - - spin_lock_irqsave(&vga_lock, flags); - vgadev = vgadev_find(pdev); - if (vgadev == NULL) { - ret = false; - goto bail; - } - - if (vga_default == pdev) - vga_set_default_device(NULL); - - if (vgadev->decodes & (VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM)) - vga_decode_count--; - - /* Remove entry from list */ - list_del(&vgadev->list); - vga_count--; - /* Notify userland driver that the device is gone so it discards - * it's copies of the pci_dev pointer - */ - vga_arb_device_card_gone(pdev); - - /* Wake up all possible waiters */ - wake_up_all(&vga_wait_queue); -bail: - spin_unlock_irqrestore(&vga_lock, flags); - kfree(vgadev); - return ret; -} - -/* this is called with the lock */ -static inline void vga_update_device_decodes(struct vga_device *vgadev, - int new_decodes) -{ - struct device *dev = &vgadev->pdev->dev; - int old_decodes, decodes_removed, decodes_unlocked; - - old_decodes = vgadev->decodes; - decodes_removed = ~new_decodes & old_decodes; - decodes_unlocked = vgadev->locks & decodes_removed; - vgadev->decodes = new_decodes; - - vgaarb_info(dev, "changed VGA decodes: olddecodes=%s,decodes=%s:owns=%s\n", - vga_iostate_to_str(old_decodes), - vga_iostate_to_str(vgadev->decodes), - vga_iostate_to_str(vgadev->owns)); - - /* if we removed locked decodes, lock count goes to zero, and release */ - if (decodes_unlocked) { - if (decodes_unlocked & VGA_RSRC_LEGACY_IO) - vgadev->io_lock_cnt = 0; - if (decodes_unlocked & VGA_RSRC_LEGACY_MEM) - vgadev->mem_lock_cnt = 0; - __vga_put(vgadev, decodes_unlocked); - } - - /* change decodes counter */ - if (old_decodes & VGA_RSRC_LEGACY_MASK && - !(new_decodes & VGA_RSRC_LEGACY_MASK)) - vga_decode_count--; - if (!(old_decodes & VGA_RSRC_LEGACY_MASK) && - new_decodes & VGA_RSRC_LEGACY_MASK) - vga_decode_count++; - vgaarb_dbg(dev, "decoding count now is: %d\n", vga_decode_count); -} - -static void __vga_set_legacy_decoding(struct pci_dev *pdev, - unsigned int decodes, - bool userspace) -{ - struct vga_device *vgadev; - unsigned long flags; - - decodes &= VGA_RSRC_LEGACY_MASK; - - spin_lock_irqsave(&vga_lock, flags); - vgadev = vgadev_find(pdev); - if (vgadev == NULL) - goto bail; - - /* don't let userspace futz with kernel driver decodes */ - if (userspace && vgadev->set_decode) - goto bail; - - /* update the device decodes + counter */ - vga_update_device_decodes(vgadev, decodes); - - /* XXX if somebody is going from "doesn't decode" to "decodes" state - * here, additional care must be taken as we may have pending owner - * ship of non-legacy region ... - */ -bail: - spin_unlock_irqrestore(&vga_lock, flags); -} - -/** - * 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. - */ -void vga_set_legacy_decoding(struct pci_dev *pdev, unsigned int decodes) -{ - __vga_set_legacy_decoding(pdev, decodes, false); -} -EXPORT_SYMBOL(vga_set_legacy_decoding); - -/** - * vga_client_register - register or unregister a VGA arbitration client - * @pdev: pci device of the VGA client - * @set_decode: vga decode change callback - * - * Clients have two callback mechanisms they can use. - * - * @set_decode callback: If a client can disable its GPU VGA resource, it - * will get a callback from this to set the encode/decode state. - * - * 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. The - * driver will get a callback when VGA arbitration is first used by userspace - * since some older X servers have issues. - * - * This function does not check whether a client for @pdev has been registered - * already. - * - * To unregister just call vga_client_unregister(). - * - * Returns: 0 on success, -1 on failure - */ -int vga_client_register(struct pci_dev *pdev, - unsigned int (*set_decode)(struct pci_dev *pdev, bool decode)) -{ - int ret = -ENODEV; - struct vga_device *vgadev; - unsigned long flags; - - spin_lock_irqsave(&vga_lock, flags); - vgadev = vgadev_find(pdev); - if (!vgadev) - goto bail; - - vgadev->set_decode = set_decode; - ret = 0; - -bail: - spin_unlock_irqrestore(&vga_lock, flags); - return ret; - -} -EXPORT_SYMBOL(vga_client_register); - -/* - * Char driver implementation - * - * Semantics is: - * - * open : open user instance of the arbitrer. by default, it's - * attached to the default VGA device of the system. - * - * close : close user instance, release locks - * - * read : return a string indicating the status of the target. - * an IO state string is of the form {io,mem,io+mem,none}, - * mc and ic are respectively mem and io lock counts (for - * debugging/diagnostic only). "decodes" indicate what the - * card currently decodes, "owns" indicates what is currently - * enabled on it, and "locks" indicates what is locked by this - * card. If the card is unplugged, we get "invalid" then for - * card_ID and an -ENODEV error is returned for any command - * until a new card is targeted - * - * "<card_ID>,decodes=<io_state>,owns=<io_state>,locks=<io_state> (ic,mc)" - * - * write : write a command to the arbiter. List of commands is: - * - * target <card_ID> : switch target to card <card_ID> (see below) - * lock <io_state> : acquires locks on target ("none" is invalid io_state) - * trylock <io_state> : non-blocking acquire locks on target - * unlock <io_state> : release locks on target - * unlock all : release all locks on target held by this user - * decodes <io_state> : set the legacy decoding attributes for the card - * - * poll : event if something change on any card (not just the target) - * - * card_ID is of the form "PCI:domain:bus:dev.fn". It can be set to "default" - * to go back to the system default card (TODO: not implemented yet). - * Currently, only PCI is supported as a prefix, but the userland API may - * support other bus types in the future, even if the current kernel - * implementation doesn't. - * - * Note about locks: - * - * The driver keeps track of which user has what locks on which card. It - * supports stacking, like the kernel one. This complexifies the implementation - * a bit, but makes the arbiter more tolerant to userspace problems and able - * to properly cleanup in all cases when a process dies. - * Currently, a max of 16 cards simultaneously can have locks issued from - * userspace for a given user (file descriptor instance) of the arbiter. - * - * If the device is hot-unplugged, there is a hook inside the module to notify - * they being added/removed in the system and automatically added/removed in - * the arbiter. - */ - -#define MAX_USER_CARDS CONFIG_VGA_ARB_MAX_GPUS -#define PCI_INVALID_CARD ((struct pci_dev *)-1UL) - -/* - * Each user has an array of these, tracking which cards have locks - */ -struct vga_arb_user_card { - struct pci_dev *pdev; - unsigned int mem_cnt; - unsigned int io_cnt; -}; - -struct vga_arb_private { - struct list_head list; - struct pci_dev *target; - struct vga_arb_user_card cards[MAX_USER_CARDS]; - spinlock_t lock; -}; - -static LIST_HEAD(vga_user_list); -static DEFINE_SPINLOCK(vga_user_lock); - - -/* - * This function gets a string in the format: "PCI:domain:bus:dev.fn" and - * returns the respective values. If the string is not in this format, - * it returns 0. - */ -static int vga_pci_str_to_vars(char *buf, int count, unsigned int *domain, - unsigned int *bus, unsigned int *devfn) -{ - int n; - unsigned int slot, func; - - - n = sscanf(buf, "PCI:%x:%x:%x.%x", domain, bus, &slot, &func); - if (n != 4) - return 0; - - *devfn = PCI_DEVFN(slot, func); - - return 1; -} - -static ssize_t vga_arb_read(struct file *file, char __user *buf, - size_t count, loff_t *ppos) -{ - struct vga_arb_private *priv = file->private_data; - struct vga_device *vgadev; - struct pci_dev *pdev; - unsigned long flags; - size_t len; - int rc; - char *lbuf; - - lbuf = kmalloc(1024, GFP_KERNEL); - if (lbuf == NULL) - return -ENOMEM; - - /* Shields against vga_arb_device_card_gone (pci_dev going - * away), and allows access to vga list - */ - spin_lock_irqsave(&vga_lock, flags); - - /* If we are targeting the default, use it */ - pdev = priv->target; - if (pdev == NULL || pdev == PCI_INVALID_CARD) { - spin_unlock_irqrestore(&vga_lock, flags); - len = sprintf(lbuf, "invalid"); - goto done; - } - - /* Find card vgadev structure */ - vgadev = vgadev_find(pdev); - if (vgadev == NULL) { - /* Wow, it's not in the list, that shouldn't happen, - * let's fix us up and return invalid card - */ - if (pdev == priv->target) - vga_arb_device_card_gone(pdev); - spin_unlock_irqrestore(&vga_lock, flags); - len = sprintf(lbuf, "invalid"); - goto done; - } - - /* Fill the buffer with infos */ - len = snprintf(lbuf, 1024, - "count:%d,PCI:%s,decodes=%s,owns=%s,locks=%s(%d:%d)\n", - vga_decode_count, pci_name(pdev), - vga_iostate_to_str(vgadev->decodes), - vga_iostate_to_str(vgadev->owns), - vga_iostate_to_str(vgadev->locks), - vgadev->io_lock_cnt, vgadev->mem_lock_cnt); - - spin_unlock_irqrestore(&vga_lock, flags); -done: - - /* Copy that to user */ - if (len > count) - len = count; - rc = copy_to_user(buf, lbuf, len); - kfree(lbuf); - if (rc) - return -EFAULT; - return len; -} - -/* - * TODO: To avoid parsing inside kernel and to improve the speed we may - * consider use ioctl here - */ -static ssize_t vga_arb_write(struct file *file, const char __user *buf, - size_t count, loff_t *ppos) -{ - struct vga_arb_private *priv = file->private_data; - struct vga_arb_user_card *uc = NULL; - struct pci_dev *pdev; - - unsigned int io_state; - - char kbuf[64], *curr_pos; - size_t remaining = count; - - int ret_val; - int i; - - if (count >= sizeof(kbuf)) - return -EINVAL; - if (copy_from_user(kbuf, buf, count)) - return -EFAULT; - curr_pos = kbuf; - kbuf[count] = '\0'; /* Just to make sure... */ - - if (strncmp(curr_pos, "lock ", 5) == 0) { - curr_pos += 5; - remaining -= 5; - - pr_debug("client 0x%p called 'lock'\n", priv); - - if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { - ret_val = -EPROTO; - goto done; - } - if (io_state == VGA_RSRC_NONE) { - ret_val = -EPROTO; - goto done; - } - - pdev = priv->target; - if (priv->target == NULL) { - ret_val = -ENODEV; - goto done; - } - - vga_get_uninterruptible(pdev, io_state); - - /* Update the client's locks lists... */ - for (i = 0; i < MAX_USER_CARDS; i++) { - if (priv->cards[i].pdev == pdev) { - if (io_state & VGA_RSRC_LEGACY_IO) - priv->cards[i].io_cnt++; - if (io_state & VGA_RSRC_LEGACY_MEM) - priv->cards[i].mem_cnt++; - break; - } - } - - ret_val = count; - goto done; - } else if (strncmp(curr_pos, "unlock ", 7) == 0) { - curr_pos += 7; - remaining -= 7; - - pr_debug("client 0x%p called 'unlock'\n", priv); - - if (strncmp(curr_pos, "all", 3) == 0) - io_state = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM; - else { - if (!vga_str_to_iostate - (curr_pos, remaining, &io_state)) { - ret_val = -EPROTO; - goto done; - } - /* TODO: Add this? - if (io_state == VGA_RSRC_NONE) { - ret_val = -EPROTO; - goto done; - } - */ - } - - pdev = priv->target; - if (priv->target == NULL) { - ret_val = -ENODEV; - goto done; - } - for (i = 0; i < MAX_USER_CARDS; i++) { - if (priv->cards[i].pdev == pdev) - uc = &priv->cards[i]; - } - - if (!uc) { - ret_val = -EINVAL; - goto done; - } - - if (io_state & VGA_RSRC_LEGACY_IO && uc->io_cnt == 0) { - ret_val = -EINVAL; - goto done; - } - - if (io_state & VGA_RSRC_LEGACY_MEM && uc->mem_cnt == 0) { - ret_val = -EINVAL; - goto done; - } - - vga_put(pdev, io_state); - - if (io_state & VGA_RSRC_LEGACY_IO) - uc->io_cnt--; - if (io_state & VGA_RSRC_LEGACY_MEM) - uc->mem_cnt--; - - ret_val = count; - goto done; - } else if (strncmp(curr_pos, "trylock ", 8) == 0) { - curr_pos += 8; - remaining -= 8; - - pr_debug("client 0x%p called 'trylock'\n", priv); - - if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { - ret_val = -EPROTO; - goto done; - } - /* TODO: Add this? - if (io_state == VGA_RSRC_NONE) { - ret_val = -EPROTO; - goto done; - } - */ - - pdev = priv->target; - if (priv->target == NULL) { - ret_val = -ENODEV; - goto done; - } - - if (vga_tryget(pdev, io_state)) { - /* Update the client's locks lists... */ - for (i = 0; i < MAX_USER_CARDS; i++) { - if (priv->cards[i].pdev == pdev) { - if (io_state & VGA_RSRC_LEGACY_IO) - priv->cards[i].io_cnt++; - if (io_state & VGA_RSRC_LEGACY_MEM) - priv->cards[i].mem_cnt++; - break; - } - } - ret_val = count; - goto done; - } else { - ret_val = -EBUSY; - goto done; - } - - } else if (strncmp(curr_pos, "target ", 7) == 0) { - unsigned int domain, bus, devfn; - struct vga_device *vgadev; - - curr_pos += 7; - remaining -= 7; - pr_debug("client 0x%p called 'target'\n", priv); - /* if target is default */ - if (!strncmp(curr_pos, "default", 7)) - pdev = pci_dev_get(vga_default_device()); - else { - if (!vga_pci_str_to_vars(curr_pos, remaining, - &domain, &bus, &devfn)) { - ret_val = -EPROTO; - goto done; - } - pdev = pci_get_domain_bus_and_slot(domain, bus, devfn); - if (!pdev) { - pr_debug("invalid PCI address %04x:%02x:%02x.%x\n", - domain, bus, PCI_SLOT(devfn), - PCI_FUNC(devfn)); - ret_val = -ENODEV; - goto done; - } - - pr_debug("%s ==> %04x:%02x:%02x.%x pdev %p\n", curr_pos, - domain, bus, PCI_SLOT(devfn), PCI_FUNC(devfn), - pdev); - } - - vgadev = vgadev_find(pdev); - pr_debug("vgadev %p\n", vgadev); - if (vgadev == NULL) { - if (pdev) { - vgaarb_dbg(&pdev->dev, "not a VGA device\n"); - pci_dev_put(pdev); - } - - ret_val = -ENODEV; - goto done; - } - - priv->target = pdev; - for (i = 0; i < MAX_USER_CARDS; i++) { - if (priv->cards[i].pdev == pdev) - break; - if (priv->cards[i].pdev == NULL) { - priv->cards[i].pdev = pdev; - priv->cards[i].io_cnt = 0; - priv->cards[i].mem_cnt = 0; - break; - } - } - if (i == MAX_USER_CARDS) { - vgaarb_dbg(&pdev->dev, "maximum user cards (%d) number reached, ignoring this one!\n", - MAX_USER_CARDS); - pci_dev_put(pdev); - /* XXX: which value to return? */ - ret_val = -ENOMEM; - goto done; - } - - ret_val = count; - pci_dev_put(pdev); - goto done; - - - } else if (strncmp(curr_pos, "decodes ", 8) == 0) { - curr_pos += 8; - remaining -= 8; - pr_debug("client 0x%p called 'decodes'\n", priv); - - if (!vga_str_to_iostate(curr_pos, remaining, &io_state)) { - ret_val = -EPROTO; - goto done; - } - pdev = priv->target; - if (priv->target == NULL) { - ret_val = -ENODEV; - goto done; - } - - __vga_set_legacy_decoding(pdev, io_state, true); - ret_val = count; - goto done; - } - /* If we got here, the message written is not part of the protocol! */ - return -EPROTO; - -done: - return ret_val; -} - -static __poll_t vga_arb_fpoll(struct file *file, poll_table *wait) -{ - pr_debug("%s\n", __func__); - - poll_wait(file, &vga_wait_queue, wait); - return EPOLLIN; -} - -static int vga_arb_open(struct inode *inode, struct file *file) -{ - struct vga_arb_private *priv; - unsigned long flags; - - pr_debug("%s\n", __func__); - - priv = kzalloc(sizeof(*priv), GFP_KERNEL); - if (priv == NULL) - return -ENOMEM; - spin_lock_init(&priv->lock); - file->private_data = priv; - - spin_lock_irqsave(&vga_user_lock, flags); - list_add(&priv->list, &vga_user_list); - spin_unlock_irqrestore(&vga_user_lock, flags); - - /* Set the client' lists of locks */ - priv->target = vga_default_device(); /* Maybe this is still null! */ - priv->cards[0].pdev = priv->target; - priv->cards[0].io_cnt = 0; - priv->cards[0].mem_cnt = 0; - - - return 0; -} - -static int vga_arb_release(struct inode *inode, struct file *file) -{ - struct vga_arb_private *priv = file->private_data; - struct vga_arb_user_card *uc; - unsigned long flags; - int i; - - pr_debug("%s\n", __func__); - - spin_lock_irqsave(&vga_user_lock, flags); - list_del(&priv->list); - for (i = 0; i < MAX_USER_CARDS; i++) { - uc = &priv->cards[i]; - if (uc->pdev == NULL) - continue; - vgaarb_dbg(&uc->pdev->dev, "uc->io_cnt == %d, uc->mem_cnt == %d\n", - uc->io_cnt, uc->mem_cnt); - while (uc->io_cnt--) - vga_put(uc->pdev, VGA_RSRC_LEGACY_IO); - while (uc->mem_cnt--) - vga_put(uc->pdev, VGA_RSRC_LEGACY_MEM); - } - spin_unlock_irqrestore(&vga_user_lock, flags); - - kfree(priv); - - return 0; -} - -static void vga_arb_device_card_gone(struct pci_dev *pdev) -{ -} - -/* - * callback any registered clients to let them know we have a - * change in VGA cards - */ -static void vga_arbiter_notify_clients(void) -{ - struct vga_device *vgadev; - unsigned long flags; - uint32_t new_decodes; - bool new_state; - - if (!vga_arbiter_used) - return; - - spin_lock_irqsave(&vga_lock, flags); - list_for_each_entry(vgadev, &vga_list, list) { - if (vga_count > 1) - new_state = false; - else - new_state = true; - if (vgadev->set_decode) { - new_decodes = vgadev->set_decode(vgadev->pdev, - new_state); - vga_update_device_decodes(vgadev, new_decodes); - } - } - spin_unlock_irqrestore(&vga_lock, flags); -} - -static int pci_notify(struct notifier_block *nb, unsigned long action, - void *data) -{ - struct device *dev = data; - struct pci_dev *pdev = to_pci_dev(dev); - bool notify = false; - - vgaarb_dbg(dev, "%s\n", __func__); - - /* For now we're only intereted in devices added and removed. I didn't - * test this thing here, so someone needs to double check for the - * cases of hotplugable vga cards. */ - if (action == BUS_NOTIFY_ADD_DEVICE) - notify = vga_arbiter_add_pci_device(pdev); - else if (action == BUS_NOTIFY_DEL_DEVICE) - notify = vga_arbiter_del_pci_device(pdev); - - if (notify) - vga_arbiter_notify_clients(); - return 0; -} - -static struct notifier_block pci_notifier = { - .notifier_call = pci_notify, -}; - -static const struct file_operations vga_arb_device_fops = { - .read = vga_arb_read, - .write = vga_arb_write, - .poll = vga_arb_fpoll, - .open = vga_arb_open, - .release = vga_arb_release, - .llseek = noop_llseek, -}; - -static struct miscdevice vga_arb_device = { - MISC_DYNAMIC_MINOR, "vga_arbiter", &vga_arb_device_fops -}; - -#if defined(CONFIG_ACPI) -static bool vga_arb_integrated_gpu(struct device *dev) -{ - struct acpi_device *adev = ACPI_COMPANION(dev); - - return adev && !strcmp(acpi_device_hid(adev), ACPI_VIDEO_HID); -} -#else -static bool vga_arb_integrated_gpu(struct device *dev) -{ - return false; -} -#endif - -static void __init vga_arb_select_default_device(void) -{ - struct pci_dev *pdev, *found = NULL; - struct vga_device *vgadev; - -#if defined(CONFIG_X86) || defined(CONFIG_IA64) - u64 base = screen_info.lfb_base; - u64 size = screen_info.lfb_size; - u64 limit; - resource_size_t start, end; - unsigned long flags; - int i; - - if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE) - base |= (u64)screen_info.ext_lfb_base << 32; - - limit = base + size; - - list_for_each_entry(vgadev, &vga_list, list) { - struct device *dev = &vgadev->pdev->dev; - /* - * Override vga_arbiter_add_pci_device()'s I/O based detection - * as it may take the wrong device (e.g. on Apple system under - * EFI). - * - * Select the device owning the boot framebuffer if there is - * one. - */ - - /* Does firmware framebuffer belong to us? */ - for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) { - flags = pci_resource_flags(vgadev->pdev, i); - - if ((flags & IORESOURCE_MEM) == 0) - continue; - - start = pci_resource_start(vgadev->pdev, i); - end = pci_resource_end(vgadev->pdev, i); - - if (!start || !end) - continue; - - if (base < start || limit >= end) - continue; - - if (!vga_default_device()) - vgaarb_info(dev, "setting as boot device\n"); - else if (vgadev->pdev != vga_default_device()) - vgaarb_info(dev, "overriding boot device\n"); - vga_set_default_device(vgadev->pdev); - } - } -#endif - - if (!vga_default_device()) { - list_for_each_entry_reverse(vgadev, &vga_list, list) { - struct device *dev = &vgadev->pdev->dev; - u16 cmd; - - pdev = vgadev->pdev; - pci_read_config_word(pdev, PCI_COMMAND, &cmd); - if (cmd & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) { - found = pdev; - if (vga_arb_integrated_gpu(dev)) - break; - } - } - } - - if (found) { - vgaarb_info(&found->dev, "setting as boot device (VGA legacy resources not available)\n"); - vga_set_default_device(found); - return; - } - - if (!vga_default_device()) { - vgadev = list_first_entry_or_null(&vga_list, - struct vga_device, list); - if (vgadev) { - struct device *dev = &vgadev->pdev->dev; - vgaarb_info(dev, "setting as boot device (VGA legacy resources not available)\n"); - vga_set_default_device(vgadev->pdev); - } - } -} - -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) - pr_err("error %d registering device\n", rc); - - bus_register_notifier(&pci_bus_type, &pci_notifier); - - /* We add all PCI devices satisfying VGA class in the arbiter by - * default */ - pdev = NULL; - while ((pdev = - pci_get_subsys(PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, - PCI_ANY_ID, pdev)) != NULL) - vga_arbiter_add_pci_device(pdev); - - list_for_each_entry(vgadev, &vga_list, list) { - struct device *dev = &vgadev->pdev->dev; - - if (vgadev->bridge_has_one_vga) - vgaarb_info(dev, "bridge control possible\n"); - else - vgaarb_info(dev, "no bridge control possible\n"); - } - - vga_arb_select_default_device(); - - pr_info("loaded\n"); - return rc; -} -subsys_initcall(vga_arb_device_init); |