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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-08-07 13:11:22 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-08-07 13:11:22 +0000 |
commit | b20732900e4636a467c0183a47f7396700f5f743 (patch) | |
tree | 42f079ff82e701ebcb76829974b4caca3e5b6798 /drivers/video/screen_info_pci.c | |
parent | Adding upstream version 6.8.12. (diff) | |
download | linux-b20732900e4636a467c0183a47f7396700f5f743.tar.xz linux-b20732900e4636a467c0183a47f7396700f5f743.zip |
Adding upstream version 6.9.7.upstream/6.9.7
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/video/screen_info_pci.c')
-rw-r--r-- | drivers/video/screen_info_pci.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/drivers/video/screen_info_pci.c b/drivers/video/screen_info_pci.c new file mode 100644 index 0000000000..6c58335171 --- /dev/null +++ b/drivers/video/screen_info_pci.c @@ -0,0 +1,136 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/pci.h> +#include <linux/printk.h> +#include <linux/screen_info.h> +#include <linux/string.h> + +static struct pci_dev *screen_info_lfb_pdev; +static size_t screen_info_lfb_bar; +static resource_size_t screen_info_lfb_offset; +static struct resource screen_info_lfb_res = DEFINE_RES_MEM(0, 0); + +static bool __screen_info_relocation_is_valid(const struct screen_info *si, struct resource *pr) +{ + u64 size = __screen_info_lfb_size(si, screen_info_video_type(si)); + + if (screen_info_lfb_offset > resource_size(pr)) + return false; + if (size > resource_size(pr)) + return false; + if (resource_size(pr) - size < screen_info_lfb_offset) + return false; + + return true; +} + +void screen_info_apply_fixups(void) +{ + struct screen_info *si = &screen_info; + + if (screen_info_lfb_pdev) { + struct resource *pr = &screen_info_lfb_pdev->resource[screen_info_lfb_bar]; + + if (pr->start != screen_info_lfb_res.start) { + if (__screen_info_relocation_is_valid(si, pr)) { + /* + * Only update base if we have an actual + * relocation to a valid I/O range. + */ + __screen_info_set_lfb_base(si, pr->start + screen_info_lfb_offset); + pr_info("Relocating firmware framebuffer to offset %pa[d] within %pr\n", + &screen_info_lfb_offset, pr); + } else { + pr_warn("Invalid relocating, disabling firmware framebuffer\n"); + } + } + } +} + +static void screen_info_fixup_lfb(struct pci_dev *pdev) +{ + unsigned int type; + struct resource res[SCREEN_INFO_MAX_RESOURCES]; + size_t i, numres; + int ret; + const struct screen_info *si = &screen_info; + + if (screen_info_lfb_pdev) + return; // already found + + type = screen_info_video_type(si); + if (type != VIDEO_TYPE_EFI) + return; // only applies to EFI + + ret = screen_info_resources(si, res, ARRAY_SIZE(res)); + if (ret < 0) + return; + numres = ret; + + for (i = 0; i < numres; ++i) { + struct resource *r = &res[i]; + const struct resource *pr; + + if (!(r->flags & IORESOURCE_MEM)) + continue; + pr = pci_find_resource(pdev, r); + if (!pr) + continue; + + /* + * We've found a PCI device with the framebuffer + * resource. Store away the parameters to track + * relocation of the framebuffer aperture. + */ + screen_info_lfb_pdev = pdev; + screen_info_lfb_bar = pr - pdev->resource; + screen_info_lfb_offset = r->start - pr->start; + memcpy(&screen_info_lfb_res, r, sizeof(screen_info_lfb_res)); + } +} +DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_ANY_ID, PCI_ANY_ID, PCI_BASE_CLASS_DISPLAY, 16, + screen_info_fixup_lfb); + +static struct pci_dev *__screen_info_pci_dev(struct resource *res) +{ + struct pci_dev *pdev = NULL; + const struct resource *r = NULL; + + if (!(res->flags & IORESOURCE_MEM)) + return NULL; + + while (!r && (pdev = pci_get_base_class(PCI_BASE_CLASS_DISPLAY, pdev))) { + r = pci_find_resource(pdev, res); + } + + return pdev; +} + +/** + * screen_info_pci_dev() - Return PCI parent device that contains screen_info's framebuffer + * @si: the screen_info + * + * Returns: + * The screen_info's parent device or NULL on success, or a pointer-encoded + * errno value otherwise. The value NULL is not an error. It signals that no + * PCI device has been found. + */ +struct pci_dev *screen_info_pci_dev(const struct screen_info *si) +{ + struct resource res[SCREEN_INFO_MAX_RESOURCES]; + ssize_t i, numres; + + numres = screen_info_resources(si, res, ARRAY_SIZE(res)); + if (numres < 0) + return ERR_PTR(numres); + + for (i = 0; i < numres; ++i) { + struct pci_dev *pdev = __screen_info_pci_dev(&res[i]); + + if (pdev) + return pdev; + } + + return NULL; +} +EXPORT_SYMBOL(screen_info_pci_dev); |