// SPDX-License-Identifier: MIT /* * Copyright © 2019 Intel Corporation */ #include <linux/pci.h> #include <linux/vgaarb.h> #include <video/vga.h> #include "soc/intel_gmch.h" #include "i915_drv.h" #include "i915_reg.h" #include "intel_de.h" #include "intel_vga.h" static i915_reg_t intel_vga_cntrl_reg(struct drm_i915_private *i915) { if (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915)) return VLV_VGACNTRL; else if (DISPLAY_VER(i915) >= 5) return CPU_VGACNTRL; else return VGACNTRL; } /* Disable the VGA plane that we never use */ void intel_vga_disable(struct drm_i915_private *dev_priv) { struct pci_dev *pdev = to_pci_dev(dev_priv->drm.dev); i915_reg_t vga_reg = intel_vga_cntrl_reg(dev_priv); u8 sr1; if (intel_de_read(dev_priv, vga_reg) & VGA_DISP_DISABLE) return; /* WaEnableVGAAccessThroughIOPort:ctg,elk,ilk,snb,ivb,vlv,hsw */ vga_get_uninterruptible(pdev, VGA_RSRC_LEGACY_IO); outb(0x01, VGA_SEQ_I); sr1 = inb(VGA_SEQ_D); outb(sr1 | VGA_SR01_SCREEN_OFF, VGA_SEQ_D); vga_put(pdev, VGA_RSRC_LEGACY_IO); udelay(300); intel_de_write(dev_priv, vga_reg, VGA_DISP_DISABLE); intel_de_posting_read(dev_priv, vga_reg); } void intel_vga_redisable_power_on(struct drm_i915_private *dev_priv) { i915_reg_t vga_reg = intel_vga_cntrl_reg(dev_priv); if (!(intel_de_read(dev_priv, vga_reg) & VGA_DISP_DISABLE)) { drm_dbg_kms(&dev_priv->drm, "Something enabled VGA plane, disabling it\n"); intel_vga_disable(dev_priv); } } void intel_vga_redisable(struct drm_i915_private *i915) { intel_wakeref_t wakeref; /* * This function can be called both from intel_modeset_setup_hw_state or * at a very early point in our resume sequence, where the power well * structures are not yet restored. Since this function is at a very * paranoid "someone might have enabled VGA while we were not looking" * level, just check if the power well is enabled instead of trying to * follow the "don't touch the power well if we don't need it" policy * the rest of the driver uses. */ wakeref = intel_display_power_get_if_enabled(i915, POWER_DOMAIN_VGA); if (!wakeref) return; intel_vga_redisable_power_on(i915); intel_display_power_put(i915, POWER_DOMAIN_VGA, wakeref); } void intel_vga_reset_io_mem(struct drm_i915_private *i915) { struct pci_dev *pdev = to_pci_dev(i915->drm.dev); /* * After we re-enable the power well, if we touch VGA register 0x3d5 * we'll get unclaimed register interrupts. This stops after we write * anything to the VGA MSR register. The vgacon module uses this * register all the time, so if we unbind our driver and, as a * consequence, bind vgacon, we'll get stuck in an infinite loop at * console_unlock(). So make here we touch the VGA MSR register, making * sure vgacon can keep working normally without triggering interrupts * and error messages. */ vga_get_uninterruptible(pdev, VGA_RSRC_LEGACY_IO); outb(inb(VGA_MIS_R), VGA_MIS_W); vga_put(pdev, VGA_RSRC_LEGACY_IO); } static unsigned int intel_vga_set_decode(struct pci_dev *pdev, bool enable_decode) { struct drm_i915_private *i915 = pdev_to_i915(pdev); intel_gmch_vga_set_state(i915, enable_decode); if (enable_decode) return VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM | VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM; else return VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM; } int intel_vga_register(struct drm_i915_private *i915) { struct pci_dev *pdev = to_pci_dev(i915->drm.dev); int ret; /* * If we have > 1 VGA cards, then we need to arbitrate access to the * common VGA resources. * * If we are a secondary display controller (!PCI_DISPLAY_CLASS_VGA), * then we do not take part in VGA arbitration and the * vga_client_register() fails with -ENODEV. */ ret = vga_client_register(pdev, intel_vga_set_decode); if (ret && ret != -ENODEV) return ret; return 0; } void intel_vga_unregister(struct drm_i915_private *i915) { struct pci_dev *pdev = to_pci_dev(i915->drm.dev); vga_client_unregister(pdev); }