git: a3ceeef26bc8 - main - arm64: lop off another 24MB of KVA for early device mappings
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Date: Thu, 23 Nov 2023 16:23:28 UTC
The branch main has been updated by kevans: URL: https://cgit.FreeBSD.org/src/commit/?id=a3ceeef26bc880b86f4e181bddd9924a2b5e0691 commit a3ceeef26bc880b86f4e181bddd9924a2b5e0691 Author: Kyle Evans <kevans@FreeBSD.org> AuthorDate: 2023-11-23 16:21:33 +0000 Commit: Kyle Evans <kevans@FreeBSD.org> CommitDate: 2023-11-23 16:23:14 +0000 arm64: lop off another 24MB of KVA for early device mappings This grows the block enough to fit a 4K 32-bit depth framebuffer; some firmware would present smaller GOP modes to be able to boot with a smaller framebuffer on these devices, but the Windows Devkit firmware is simply not that nice. Instead, it offers exactly one GOP mode that matches the current resolution of the attached display, so with limited control over resolution on most of my displays it'd be nice if we could Just Work(TM) at 4K. andrew notes that he has some ideas for removing PMAP_MAPDEV_EARLY_SIZE entirely, so this limitation could end up removed altogether in the future. Reviewed by: andrew, emaste Differential Revision: https://reviews.freebsd.org/D42726 --- sys/arm64/include/pte.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/sys/arm64/include/pte.h b/sys/arm64/include/pte.h index f067feabe365..c3d0394e6e9f 100644 --- a/sys/arm64/include/pte.h +++ b/sys/arm64/include/pte.h @@ -164,7 +164,11 @@ typedef uint64_t pt_entry_t; /* page table entry */ /* 0x2 also marks an invalid address */ #define L3_PAGE 0x3 -#define PMAP_MAPDEV_EARLY_SIZE (L2_SIZE * 8) +/* + * A substantial portion of this is to make sure that we can cope with 4K + * framebuffers in early boot, assuming a common 4K resolution @ 32-bit depth. + */ +#define PMAP_MAPDEV_EARLY_SIZE (L2_SIZE * 20) #if PAGE_SIZE == PAGE_SIZE_4K #define L0_ENTRIES_SHIFT 9