6.6-stable review patch. If anyone has any objections, please let me know.
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From: Thomas Zimmermann tzimmermann@suse.de
[ Upstream commit 75fa9b7e375e35739663cde0252d31e586c6314a ]
The plain values as stored in struct screen_info need to be decoded before being used. Add helpers that decode the type of video output and the framebuffer I/O aperture.
Old or non-x86 systems may not set the type of video directly, but only indicate the presence by storing 0x01 in orig_video_isVGA. The decoding logic in screen_info_video_type() takes this into account. It then follows similar code in vgacon's vgacon_startup() to detect the video type from the given values.
A call to screen_info_resources() returns all known resources of the given screen_info. The resources' values have been taken from existing code in vgacon and vga16fb. These drivers can later be converted to use the new interfaces.
v2: * return ssize_t from screen_info_resources() * don't call __screen_info_has_lfb() unnecessarily
Signed-off-by: Thomas Zimmermann tzimmermann@suse.de Reviewed-by: Javier Martinez Canillas javierm@redhat.com Link: https://patchwork.freedesktop.org/patch/msgid/20240212090736.11464-2-tzimmer... Stable-dep-of: c2bc958b2b03 ("fbdev: vesafb: Detect VGA compatibility from screen info's VESA attributes") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/firmware/Kconfig | 1 + drivers/video/Kconfig | 4 + drivers/video/Makefile | 3 + drivers/video/screen_info_generic.c | 146 ++++++++++++++++++++++++++++ include/linux/screen_info.h | 100 +++++++++++++++++++ 5 files changed, 254 insertions(+) create mode 100644 drivers/video/screen_info_generic.c
diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig index b59e3041fd627..f0e9f250669e2 100644 --- a/drivers/firmware/Kconfig +++ b/drivers/firmware/Kconfig @@ -229,6 +229,7 @@ config QCOM_SCM_DOWNLOAD_MODE_DEFAULT config SYSFB bool select BOOT_VESA_SUPPORT + select SCREEN_INFO
config SYSFB_SIMPLEFB bool "Mark VGA/VBE/EFI FB as generic system framebuffer" diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig index b694d7669d320..1eb755a94940a 100644 --- a/drivers/video/Kconfig +++ b/drivers/video/Kconfig @@ -11,6 +11,10 @@ config APERTURE_HELPERS Support tracking and hand-over of aperture ownership. Required by graphics drivers for firmware-provided framebuffers.
+config SCREEN_INFO + bool + default n + config STI_CORE bool depends on PARISC diff --git a/drivers/video/Makefile b/drivers/video/Makefile index 6bbc039508995..b929b664d52cd 100644 --- a/drivers/video/Makefile +++ b/drivers/video/Makefile @@ -1,12 +1,15 @@ # SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_APERTURE_HELPERS) += aperture.o +obj-$(CONFIG_SCREEN_INFO) += screen_info.o obj-$(CONFIG_STI_CORE) += sticore.o obj-$(CONFIG_VGASTATE) += vgastate.o obj-$(CONFIG_VIDEO_CMDLINE) += cmdline.o obj-$(CONFIG_VIDEO_NOMODESET) += nomodeset.o obj-$(CONFIG_HDMI) += hdmi.o
+screen_info-y := screen_info_generic.o + obj-$(CONFIG_VT) += console/ obj-$(CONFIG_FB_STI) += console/ obj-$(CONFIG_LOGO) += logo/ diff --git a/drivers/video/screen_info_generic.c b/drivers/video/screen_info_generic.c new file mode 100644 index 0000000000000..64117c6367abb --- /dev/null +++ b/drivers/video/screen_info_generic.c @@ -0,0 +1,146 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/export.h> +#include <linux/ioport.h> +#include <linux/screen_info.h> +#include <linux/string.h> + +static void resource_init_named(struct resource *r, + resource_size_t start, resource_size_t size, + const char *name, unsigned int flags) +{ + memset(r, 0, sizeof(*r)); + + r->start = start; + r->end = start + size - 1; + r->name = name; + r->flags = flags; +} + +static void resource_init_io_named(struct resource *r, + resource_size_t start, resource_size_t size, + const char *name) +{ + resource_init_named(r, start, size, name, IORESOURCE_IO); +} + +static void resource_init_mem_named(struct resource *r, + resource_size_t start, resource_size_t size, + const char *name) +{ + resource_init_named(r, start, size, name, IORESOURCE_MEM); +} + +static inline bool __screen_info_has_ega_gfx(unsigned int mode) +{ + switch (mode) { + case 0x0d: /* 320x200-4 */ + case 0x0e: /* 640x200-4 */ + case 0x0f: /* 640x350-1 */ + case 0x10: /* 640x350-4 */ + return true; + default: + return false; + } +} + +static inline bool __screen_info_has_vga_gfx(unsigned int mode) +{ + switch (mode) { + case 0x10: /* 640x480-1 */ + case 0x12: /* 640x480-4 */ + case 0x13: /* 320-200-8 */ + case 0x6a: /* 800x600-4 (VESA) */ + return true; + default: + return __screen_info_has_ega_gfx(mode); + } +} + +/** + * screen_info_resources() - Get resources from screen_info structure + * @si: the screen_info + * @r: pointer to an array of resource structures + * @num: number of elements in @r: + * + * Returns: + * The number of resources stored in @r on success, or a negative errno code otherwise. + * + * A call to screen_info_resources() returns the resources consumed by the + * screen_info's device or framebuffer. The result is stored in the caller-supplied + * array @r with up to @num elements. The function returns the number of + * initialized elements. + */ +ssize_t screen_info_resources(const struct screen_info *si, struct resource *r, size_t num) +{ + struct resource *pos = r; + unsigned int type = screen_info_video_type(si); + u64 base, size; + + switch (type) { + case VIDEO_TYPE_MDA: + if (num > 0) + resource_init_io_named(pos++, 0x3b0, 12, "mda"); + if (num > 1) + resource_init_io_named(pos++, 0x3bf, 0x01, "mda"); + if (num > 2) + resource_init_mem_named(pos++, 0xb0000, 0x2000, "mda"); + break; + case VIDEO_TYPE_CGA: + if (num > 0) + resource_init_io_named(pos++, 0x3d4, 0x02, "cga"); + if (num > 1) + resource_init_mem_named(pos++, 0xb8000, 0x2000, "cga"); + break; + case VIDEO_TYPE_EGAM: + if (num > 0) + resource_init_io_named(pos++, 0x3bf, 0x10, "ega"); + if (num > 1) + resource_init_mem_named(pos++, 0xb0000, 0x8000, "ega"); + break; + case VIDEO_TYPE_EGAC: + if (num > 0) + resource_init_io_named(pos++, 0x3c0, 0x20, "ega"); + if (num > 1) { + if (__screen_info_has_ega_gfx(si->orig_video_mode)) + resource_init_mem_named(pos++, 0xa0000, 0x10000, "ega"); + else + resource_init_mem_named(pos++, 0xb8000, 0x8000, "ega"); + } + break; + case VIDEO_TYPE_VGAC: + if (num > 0) + resource_init_io_named(pos++, 0x3c0, 0x20, "vga+"); + if (num > 1) { + if (__screen_info_has_vga_gfx(si->orig_video_mode)) + resource_init_mem_named(pos++, 0xa0000, 0x10000, "vga+"); + else + resource_init_mem_named(pos++, 0xb8000, 0x8000, "vga+"); + } + break; + case VIDEO_TYPE_VLFB: + case VIDEO_TYPE_EFI: + base = __screen_info_lfb_base(si); + if (!base) + break; + size = __screen_info_lfb_size(si, type); + if (!size) + break; + if (num > 0) + resource_init_mem_named(pos++, base, size, "lfb"); + break; + case VIDEO_TYPE_PICA_S3: + case VIDEO_TYPE_MIPS_G364: + case VIDEO_TYPE_SGI: + case VIDEO_TYPE_TGAC: + case VIDEO_TYPE_SUN: + case VIDEO_TYPE_SUNPCI: + case VIDEO_TYPE_PMAC: + default: + /* not supported */ + return -EINVAL; + } + + return pos - r; +} +EXPORT_SYMBOL(screen_info_resources); diff --git a/include/linux/screen_info.h b/include/linux/screen_info.h index eab7081392d50..e7a02c5609d12 100644 --- a/include/linux/screen_info.h +++ b/include/linux/screen_info.h @@ -4,6 +4,106 @@
#include <uapi/linux/screen_info.h>
+/** + * SCREEN_INFO_MAX_RESOURCES - maximum number of resources per screen_info + */ +#define SCREEN_INFO_MAX_RESOURCES 3 + +struct resource; + +static inline bool __screen_info_has_lfb(unsigned int type) +{ + return (type == VIDEO_TYPE_VLFB) || (type == VIDEO_TYPE_EFI); +} + +static inline u64 __screen_info_lfb_base(const struct screen_info *si) +{ + u64 lfb_base = si->lfb_base; + + if (si->capabilities & VIDEO_CAPABILITY_64BIT_BASE) + lfb_base |= (u64)si->ext_lfb_base << 32; + + return lfb_base; +} + +static inline u64 __screen_info_lfb_size(const struct screen_info *si, unsigned int type) +{ + u64 lfb_size = si->lfb_size; + + if (type == VIDEO_TYPE_VLFB) + lfb_size <<= 16; + return lfb_size; +} + +static inline unsigned int __screen_info_video_type(unsigned int type) +{ + switch (type) { + case VIDEO_TYPE_MDA: + case VIDEO_TYPE_CGA: + case VIDEO_TYPE_EGAM: + case VIDEO_TYPE_EGAC: + case VIDEO_TYPE_VGAC: + case VIDEO_TYPE_VLFB: + case VIDEO_TYPE_PICA_S3: + case VIDEO_TYPE_MIPS_G364: + case VIDEO_TYPE_SGI: + case VIDEO_TYPE_TGAC: + case VIDEO_TYPE_SUN: + case VIDEO_TYPE_SUNPCI: + case VIDEO_TYPE_PMAC: + case VIDEO_TYPE_EFI: + return type; + default: + return 0; + } +} + +/** + * screen_info_video_type() - Decodes the video type from struct screen_info + * @si: an instance of struct screen_info + * + * Returns: + * A VIDEO_TYPE_ constant representing si's type of video display, or 0 otherwise. + */ +static inline unsigned int screen_info_video_type(const struct screen_info *si) +{ + unsigned int type; + + // check if display output is on + if (!si->orig_video_isVGA) + return 0; + + // check for a known VIDEO_TYPE_ constant + type = __screen_info_video_type(si->orig_video_isVGA); + if (type) + return si->orig_video_isVGA; + + // check if text mode has been initialized + if (!si->orig_video_lines || !si->orig_video_cols) + return 0; + + // 80x25 text, mono + if (si->orig_video_mode == 0x07) { + if ((si->orig_video_ega_bx & 0xff) != 0x10) + return VIDEO_TYPE_EGAM; + else + return VIDEO_TYPE_MDA; + } + + // EGA/VGA, 16 colors + if ((si->orig_video_ega_bx & 0xff) != 0x10) { + if (si->orig_video_isVGA) + return VIDEO_TYPE_VGAC; + else + return VIDEO_TYPE_EGAC; + } + + // the rest... + return VIDEO_TYPE_CGA; +} + +ssize_t screen_info_resources(const struct screen_info *si, struct resource *r, size_t num); + extern struct screen_info screen_info;
#endif /* _SCREEN_INFO_H */