Split the small bit of code that does default VGA handling out from the arbiter. Add a Kconfig option to allow the kernel to be built with just the default handling, or the arbiter and default handling.
While doing this, rename the functions from vga_(set_)default_device to pci_(set_)default_display. This makes it clear that these functions do not rely on legacy VGA access: they're about the default PCI display. (The device still needs to be a member of PCI_CLASS_DISPLAY_VGA.)
This should not introduce any functional change.
Signed-off-by: Daniel Axtens dja@axtens.net
---
I know this adds another config option and that's a bit sad, but we can't include it unconditionally as it depends on PCI. Suggestions welcome.
v3: split from the part where we add functionality rename functions --- arch/ia64/pci/fixup.c | 6 +-- arch/powerpc/kernel/pci-common.c | 6 +-- arch/x86/pci/fixup.c | 6 +-- arch/x86/video/fbdev.c | 4 +- drivers/gpu/vga/Kconfig | 12 ++++++ drivers/gpu/vga/Makefile | 1 + drivers/gpu/vga/default_display.c | 86 +++++++++++++++++++++++++++++++++++++++ drivers/gpu/vga/vga_switcheroo.c | 8 ++-- drivers/gpu/vga/vgaarb.c | 61 ++++++--------------------- drivers/pci/pci-sysfs.c | 4 +- include/linux/default_display.h | 44 ++++++++++++++++++++ include/linux/vgaarb.h | 15 ------- 12 files changed, 173 insertions(+), 80 deletions(-) create mode 100644 drivers/gpu/vga/default_display.c create mode 100644 include/linux/default_display.h
diff --git a/arch/ia64/pci/fixup.c b/arch/ia64/pci/fixup.c index 41caa99add51..a5f35e767c84 100644 --- a/arch/ia64/pci/fixup.c +++ b/arch/ia64/pci/fixup.c @@ -5,7 +5,7 @@
#include <linux/pci.h> #include <linux/init.h> -#include <linux/vgaarb.h> +#include <linux/default_display.h> #include <linux/screen_info.h>
#include <asm/machvec.h> @@ -22,7 +22,7 @@ * card with this copy. On laptops this copy has to be used since * the main ROM may be compressed or combined with another image. * See pci_map_rom() for use of this flag. Before marking the device - * with IORESOURCE_ROM_SHADOW check if a vga_default_device is already set + * with IORESOURCE_ROM_SHADOW check if a pci_default_display is already set * by either arch code or vga-arbitration; if so only apply the fixup to this * already-determined primary video card. */ @@ -59,7 +59,7 @@ static void pci_fixup_video(struct pci_dev *pdev) } bus = bus->parent; } - if (!vga_default_device() || pdev == vga_default_device()) { + if (!pci_default_display() || pdev == pci_default_display()) { pci_read_config_word(pdev, PCI_COMMAND, &config); if (config & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) { res = &pdev->resource[PCI_ROM_RESOURCE]; diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index 341a7469cab8..9f82f13ac531 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -31,7 +31,7 @@ #include <linux/irq.h> #include <linux/vmalloc.h> #include <linux/slab.h> -#include <linux/vgaarb.h> +#include <linux/default_display.h>
#include <asm/processor.h> #include <asm/io.h> @@ -1747,8 +1747,8 @@ static void fixup_vga(struct pci_dev *pdev) u16 cmd;
pci_read_config_word(pdev, PCI_COMMAND, &cmd); - if ((cmd & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) || !vga_default_device()) - vga_set_default_device(pdev); + if ((cmd & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) || !pci_default_display()) + pci_set_default_display(pdev);
} DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_ANY_ID, PCI_ANY_ID, diff --git a/arch/x86/pci/fixup.c b/arch/x86/pci/fixup.c index 11e407489db0..7e32a2a80383 100644 --- a/arch/x86/pci/fixup.c +++ b/arch/x86/pci/fixup.c @@ -5,7 +5,7 @@ #include <linux/delay.h> #include <linux/dmi.h> #include <linux/pci.h> -#include <linux/vgaarb.h> +#include <linux/default_display.h> #include <asm/hpet.h> #include <asm/pci_x86.h>
@@ -302,7 +302,7 @@ DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_MCH_PC1, pcie_r * card with this copy. On laptops this copy has to be used since * the main ROM may be compressed or combined with another image. * See pci_map_rom() for use of this flag. Before marking the device - * with IORESOURCE_ROM_SHADOW check if a vga_default_device is already set + * with IORESOURCE_ROM_SHADOW check if a pci_default_display is already set * by either arch code or vga-arbitration; if so only apply the fixup to this * already-determined primary video card. */ @@ -334,7 +334,7 @@ static void pci_fixup_video(struct pci_dev *pdev) } bus = bus->parent; } - if (!vga_default_device() || pdev == vga_default_device()) { + if (!pci_default_display() || pdev == pci_default_display()) { pci_read_config_word(pdev, PCI_COMMAND, &config); if (config & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) { res = &pdev->resource[PCI_ROM_RESOURCE]; diff --git a/arch/x86/video/fbdev.c b/arch/x86/video/fbdev.c index 9fd24846d094..114bd9ac95d0 100644 --- a/arch/x86/video/fbdev.c +++ b/arch/x86/video/fbdev.c @@ -9,12 +9,12 @@ #include <linux/fb.h> #include <linux/pci.h> #include <linux/module.h> -#include <linux/vgaarb.h> +#include <linux/default_display.h>
int fb_is_primary_device(struct fb_info *info) { struct device *device = info->device; - struct pci_dev *default_device = vga_default_device(); + struct pci_dev *default_device = pci_default_display(); struct pci_dev *pci_dev; struct resource *res;
diff --git a/drivers/gpu/vga/Kconfig b/drivers/gpu/vga/Kconfig index 29437eabe095..8e6edfb6d160 100644 --- a/drivers/gpu/vga/Kconfig +++ b/drivers/gpu/vga/Kconfig @@ -1,3 +1,14 @@ +config DEFAULT_DISPLAY + bool "Default Display Device Support" if EXPERT + default y + depends on PCI + help + Some programs find it helpful to know what PCI display device is the + default. On platforms like x86 this means the device used by the BIOS + to show early boot messages. On other platforms this may be an arbitrary + PCI graphics card. Select this to have a default device recorded within + the kernel and exposed to userspace through sysfs. + config VGA_ARB bool "VGA Arbitration" if EXPERT default y @@ -22,6 +33,7 @@ config VGA_SWITCHEROO depends on X86 depends on ACPI select VGA_ARB + select DEFAULT_DISPLAY help Many laptops released in 2008/9/10 have two GPUs with a multiplexer to switch between them. This adds support for dynamic switching when diff --git a/drivers/gpu/vga/Makefile b/drivers/gpu/vga/Makefile index 14ca30b75d0a..3abf32c26de5 100644 --- a/drivers/gpu/vga/Makefile +++ b/drivers/gpu/vga/Makefile @@ -1,2 +1,3 @@ obj-$(CONFIG_VGA_ARB) += vgaarb.o +obj-$(CONFIG_DEFAULT_DISPLAY) += default_display.o obj-$(CONFIG_VGA_SWITCHEROO) += vga_switcheroo.o diff --git a/drivers/gpu/vga/default_display.c b/drivers/gpu/vga/default_display.c new file mode 100644 index 000000000000..99e4723360da --- /dev/null +++ b/drivers/gpu/vga/default_display.c @@ -0,0 +1,86 @@ +/* + * default_display.c: What is the default/boot PCI VGA device? + * + * (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 + * (C) Copyright 2017 Canonical Ltd. (Author: Daniel Axtens dja@axtens.net) + * + * (License from vgaarb.c) + * 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. + */ + +/** + * DOC: overview + * + * What device should a graphics system draw to? + * + * It is helpful to have a concept of a default or boot device (for + * example, for autoconfiguration where there is no device speficied + * by the user). That should be: + * + * 1) If the platform has a concept of a boot device for early boot + * messages (think BIOS displays on x86), that device. + * + * 2) Anything specified by an arch hook, + * e.g. arch/powerpc/kernel/pci-common.c::fixup_vga() + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/pci.h> +#include <linux/init.h> + +#include <linux/default_display.h> + +static struct pci_dev *vga_default; + +/** + * pci_default_display - return the default display device + * + * This represents the default or boot device. + * + * The default implementation is rather dumb and will probably only + * work properly on single vga card setups and/or x86 platforms. + */ +struct pci_dev *pci_default_display(void) +{ + return vga_default; +} +EXPORT_SYMBOL_GPL(pci_default_display); + +/** + * pci_set_default_display - set the default display device + * @pdev: pci device to set as default + * + * Idempotent - safe to call with the same device repeatedly. + * + * Drops a reference to the old default, if applicable. Takes a + * reference to the new device. + */ +void pci_set_default_display(struct pci_dev *pdev) +{ + if (vga_default == pdev) + return; + + pci_dev_put(vga_default); + vga_default = pci_dev_get(pdev); +} diff --git a/drivers/gpu/vga/vga_switcheroo.c b/drivers/gpu/vga/vga_switcheroo.c index 3cd153c6d271..beefefc288f9 100644 --- a/drivers/gpu/vga/vga_switcheroo.c +++ b/drivers/gpu/vga/vga_switcheroo.c @@ -41,7 +41,7 @@ #include <linux/pm_runtime.h> #include <linux/seq_file.h> #include <linux/uaccess.h> -#include <linux/vgaarb.h> +#include <linux/default_display.h> #include <linux/vga_switcheroo.h>
/** @@ -320,7 +320,7 @@ int vga_switcheroo_register_client(struct pci_dev *pdev, bool driver_power_control) { return register_client(pdev, ops, VGA_SWITCHEROO_UNKNOWN_ID, - pdev == vga_default_device(), + pdev == pci_default_display(), driver_power_control); } EXPORT_SYMBOL(vga_switcheroo_register_client); @@ -397,7 +397,7 @@ bool vga_switcheroo_client_probe_defer(struct pci_dev *pdev) * apple-gmux is needed on pre-retina MacBook Pro * to probe the panel if pdev is the inactive GPU. */ - if (apple_gmux_present() && pdev != vga_default_device() && + if (apple_gmux_present() && pdev != pci_default_display() && !vgasr_priv.handler_flags) return true; } @@ -659,7 +659,7 @@ static int vga_switchto_stage1(struct vga_switcheroo_client *new_client) if (new_client->pwr_state == VGA_SWITCHEROO_OFF) vga_switchon(new_client);
- vga_set_default_device(new_client->pdev); + pci_set_default_display(new_client->pdev); return 0; }
diff --git a/drivers/gpu/vga/vgaarb.c b/drivers/gpu/vga/vgaarb.c index 76875f6299b8..7654bb678587 100644 --- a/drivers/gpu/vga/vgaarb.c +++ b/drivers/gpu/vga/vgaarb.c @@ -51,6 +51,7 @@
#include <linux/uaccess.h>
+#include <linux/default_display.h> #include <linux/vgaarb.h>
static void vga_arbiter_notify_clients(void); @@ -119,9 +120,6 @@ static int vga_str_to_iostate(char *buf, int str_size, int *io_state) 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 */ @@ -135,39 +133,6 @@ static struct vga_device *vgadev_find(struct pci_dev *pdev) 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); -} - static inline void vga_irq_set_state(struct vga_device *vgadev, bool state) { if (vgadev->irq_set_state) @@ -423,7 +388,7 @@ int vga_get(struct pci_dev *pdev, unsigned int rsrc, int interruptible) vga_check_first_use(); /* The one who calls us should check for this, but lets be sure... */ if (pdev == NULL) - pdev = vga_default_device(); + pdev = pci_default_display(); if (pdev == NULL) return 0;
@@ -490,7 +455,7 @@ int vga_tryget(struct pci_dev *pdev, unsigned int rsrc)
/* The one who calls us should check for this, but lets be sure... */ if (pdev == NULL) - pdev = vga_default_device(); + pdev = pci_default_display(); if (pdev == NULL) return 0; spin_lock_irqsave(&vga_lock, flags); @@ -524,7 +489,7 @@ void vga_put(struct pci_dev *pdev, unsigned int rsrc)
/* The one who calls us should check for this, but lets be sure... */ if (pdev == NULL) - pdev = vga_default_device(); + pdev = pci_default_display(); if (pdev == NULL) return; spin_lock_irqsave(&vga_lock, flags); @@ -667,10 +632,10 @@ static bool vga_arbiter_add_pci_device(struct pci_dev *pdev) /* Deal with VGA default device. Use first enabled one * by default if arch doesn't have it's own hook */ - if (vga_default == NULL && + if (pci_default_display() == 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); + pci_set_default_display(pdev); }
vga_arbiter_check_bridge_sharing(vgadev); @@ -704,8 +669,8 @@ static bool vga_arbiter_del_pci_device(struct pci_dev *pdev) goto bail; }
- if (vga_default == pdev) - vga_set_default_device(NULL); + if (pci_default_display() == pdev) + pci_set_default_display(NULL);
if (vgadev->decodes & (VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM)) vga_decode_count--; @@ -1182,7 +1147,7 @@ static ssize_t vga_arb_write(struct file *file, const char __user *buf, 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()); + pdev = pci_dev_get(pci_default_display()); else { if (!vga_pci_str_to_vars(curr_pos, remaining, &domain, &bus, &devfn)) { @@ -1292,7 +1257,7 @@ static int vga_arb_open(struct inode *inode, struct file *file) spin_unlock_irqrestore(&vga_user_lock, flags);
/* Set the client' lists of locks */ - priv->target = vga_default_device(); /* Maybe this is still null! */ + priv->target = pci_default_display(); /* Maybe this is still null! */ priv->cards[0].pdev = priv->target; priv->cards[0].io_cnt = 0; priv->cards[0].mem_cnt = 0; @@ -1455,11 +1420,11 @@ static int __init vga_arb_device_init(void) if (screen_info.lfb_base < start || limit >= end) continue;
- if (!vga_default_device()) + if (!pci_default_display()) vgaarb_info(dev, "setting as boot device\n"); - else if (vgadev->pdev != vga_default_device()) + else if (vgadev->pdev != pci_default_display()) vgaarb_info(dev, "overriding boot device\n"); - vga_set_default_device(vgadev->pdev); + pci_set_default_display(vgadev->pdev); } #endif if (vgadev->bridge_has_one_vga) diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 1eecfa301f7f..31a37178fa8a 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -27,7 +27,7 @@ #include <linux/security.h> #include <linux/pci-aspm.h> #include <linux/slab.h> -#include <linux/vgaarb.h> +#include <linux/default_display.h> #include <linux/pm_runtime.h> #include <linux/of.h> #include "pci.h" @@ -785,7 +785,7 @@ static ssize_t boot_vga_show(struct device *dev, struct device_attribute *attr, char *buf) { struct pci_dev *pdev = to_pci_dev(dev); - struct pci_dev *vga_dev = vga_default_device(); + struct pci_dev *vga_dev = pci_default_display();
if (vga_dev) return sprintf(buf, "%u\n", (pdev == vga_dev)); diff --git a/include/linux/default_display.h b/include/linux/default_display.h new file mode 100644 index 000000000000..5ccebde96b6a --- /dev/null +++ b/include/linux/default_display.h @@ -0,0 +1,44 @@ +/* + * default_display.h: What is the default/boot PCI VGA device? + * + * (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 + * (C) Copyright 2017 Canonical Ltd. (Author: Daniel Axtens dja@axtens.net) + * + * (License from vgaarb.h) + * 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. + */ + +#ifndef LINUX_DEFAULT_DISPLAY_H +#define LINUX_DEFAULT_DISPLAY_H + +struct pci_dev; + +#ifdef CONFIG_DEFAULT_DISPLAY +extern struct pci_dev *pci_default_display(void); +extern void pci_set_default_display(struct pci_dev *pdev); +#else +static inline struct pci_dev *pci_default_display(void) { return NULL; }; +static inline void pci_set_default_display(struct pci_dev *pdev) { }; +#endif + +#endif diff --git a/include/linux/vgaarb.h b/include/linux/vgaarb.h index ee162e3e879b..5434ad4af32d 100644 --- a/include/linux/vgaarb.h +++ b/include/linux/vgaarb.h @@ -42,12 +42,6 @@ #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) - struct pci_dev;
/* For use by clients */ @@ -121,15 +115,6 @@ extern void vga_put(struct pci_dev *pdev, unsigned int rsrc); #define vga_put(pdev, rsrc) #endif
- -#ifdef CONFIG_VGA_ARB -extern struct pci_dev *vga_default_device(void); -extern void vga_set_default_device(struct pci_dev *pdev); -#else -static inline struct pci_dev *vga_default_device(void) { return NULL; }; -static inline void vga_set_default_device(struct pci_dev *pdev) { }; -#endif - /* * Architectures should define this if they have several * independent PCI domains that can afford concurrent VGA