enable_mmu

在啟動的時候，將init_pg_dir寫入到了ttbr1_el1，idmap_pg_dir寫入到了ttbr0_el1

事實上在secondary_startup和cpu_resume時，我們又將swapper_pg_dir寫入到了ttbr_el1

SYM_CODE_START(cpu_resume)bl init_kernel_elbl switch_to_vhebl __cpu_setup/* enable the MMU early - so we can access sleep_save_stash by va */adrp x1, swapper_pg_dirbl __enable_mmuldr x8, =_cpu_resumebr x8 SYM_CODE_END(cpu_resume)SYM_FUNC_START_LOCAL(secondary_startup)/** Common entry point for secondary CPUs.*/bl switch_to_vhebl __cpu_secondary_check52bitvabl __cpu_setup // initialise processoradrp x1, swapper_pg_dirbl __enable_mmuldr x8, =__secondary_switchedbr x8 SYM_FUNC_END(secondary_startup)SYM_FUNC_START(__enable_mmu)mrs x2, ID_AA64MMFR0_EL1ubfx x2, x2, #ID_AA64MMFR0_TGRAN_SHIFT, 4cmp x2, #ID_AA64MMFR0_TGRAN_SUPPORTED_MINb.lt __no_granule_supportcmp x2, #ID_AA64MMFR0_TGRAN_SUPPORTED_MAXb.gt __no_granule_supportupdate_early_cpu_boot_status 0, x2, x3adrp x2, idmap_pg_dirphys_to_ttbr x1, x1phys_to_ttbr x2, x2msr ttbr0_el1, x2 // load TTBR0offset_ttbr1 x1, x3msr ttbr1_el1, x1 // load TTBR1isbset_sctlr_el1 x0ret SYM_FUNC_END(__enable_mmu)

那么init_pg_dir和swapper_pg_dir有啥關系呢？

總結

以上是生活随笔為你收集整理的Linux Kernel 5.10 aarch64体系对TTBR寄存器的设置的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。