diff options
Diffstat (limited to 'arch/arm64/include/asm/assembler.h')
| -rw-r--r-- | arch/arm64/include/asm/assembler.h | 131 |
1 files changed, 38 insertions, 93 deletions
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 5846145be523..ab8b396428da 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -12,7 +12,7 @@ #ifndef __ASM_ASSEMBLER_H #define __ASM_ASSEMBLER_H -#include <asm-generic/export.h> +#include <linux/export.h> #include <asm/alternative.h> #include <asm/asm-bug.h> @@ -34,28 +34,10 @@ wx\n .req w\n .endr - .macro save_and_disable_daif, flags - mrs \flags, daif - msr daifset, #0xf - .endm - .macro disable_daif msr daifset, #0xf .endm - .macro enable_daif - msr daifclr, #0xf - .endm - - .macro restore_daif, flags:req - msr daif, \flags - .endm - - /* IRQ/FIQ are the lowest priority flags, unconditionally unmask the rest. */ - .macro enable_da - msr daifclr, #(8 | 4) - .endm - /* * Save/restore interrupts. */ @@ -293,7 +275,7 @@ alternative_endif alternative_if_not ARM64_KVM_PROTECTED_MODE ASM_BUG() alternative_else_nop_endif -alternative_cb kvm_compute_final_ctr_el0 +alternative_cb ARM64_ALWAYS_SYSTEM, kvm_compute_final_ctr_el0 movz \reg, #0 movk \reg, #0, lsl #16 movk \reg, #0, lsl #32 @@ -360,20 +342,6 @@ alternative_cb_end .endm /* - * idmap_get_t0sz - get the T0SZ value needed to cover the ID map - * - * Calculate the maximum allowed value for TCR_EL1.T0SZ so that the - * entire ID map region can be mapped. As T0SZ == (64 - #bits used), - * this number conveniently equals the number of leading zeroes in - * the physical address of _end. - */ - .macro idmap_get_t0sz, reg - adrp \reg, _end - orr \reg, \reg, #(1 << VA_BITS_MIN) - 1 - clz \reg, \reg - .endm - -/* * tcr_compute_pa_size - set TCR.(I)PS to the highest supported * ID_AA64MMFR0_EL1.PARange value * @@ -384,8 +352,8 @@ alternative_cb_end .macro tcr_compute_pa_size, tcr, pos, tmp0, tmp1 mrs \tmp0, ID_AA64MMFR0_EL1 // Narrow PARange to fit the PS field in TCR_ELx - ubfx \tmp0, \tmp0, #ID_AA64MMFR0_PARANGE_SHIFT, #3 - mov \tmp1, #ID_AA64MMFR0_PARANGE_MAX + ubfx \tmp0, \tmp0, #ID_AA64MMFR0_EL1_PARANGE_SHIFT, #3 + mov \tmp1, #ID_AA64MMFR0_EL1_PARANGE_MAX cmp \tmp0, \tmp1 csel \tmp0, \tmp1, \tmp0, hi bfi \tcr, \tmp0, \pos, #3 @@ -512,7 +480,7 @@ alternative_endif */ .macro reset_pmuserenr_el0, tmpreg mrs \tmpreg, id_aa64dfr0_el1 - sbfx \tmpreg, \tmpreg, #ID_AA64DFR0_PMUVER_SHIFT, #4 + sbfx \tmpreg, \tmpreg, #ID_AA64DFR0_EL1_PMUVer_SHIFT, #4 cmp \tmpreg, #1 // Skip if no PMU present b.lt 9000f msr pmuserenr_el0, xzr // Disable PMU access from EL0 @@ -524,7 +492,7 @@ alternative_endif */ .macro reset_amuserenr_el0, tmpreg mrs \tmpreg, id_aa64pfr0_el1 // Check ID_AA64PFR0_EL1 - ubfx \tmpreg, \tmpreg, #ID_AA64PFR0_AMU_SHIFT, #4 + ubfx \tmpreg, \tmpreg, #ID_AA64PFR0_EL1_AMU_SHIFT, #4 cbz \tmpreg, .Lskip_\@ // Skip if no AMU present msr_s SYS_AMUSERENR_EL0, xzr // Disable AMU access from EL0 .Lskip_\@: @@ -604,29 +572,27 @@ alternative_endif .endm /* - * Offset ttbr1 to allow for 48-bit kernel VAs set with 52-bit PTRS_PER_PGD. + * If the kernel is built for 52-bit virtual addressing but the hardware only + * supports 48 bits, we cannot program the pgdir address into TTBR1 directly, + * but we have to add an offset so that the TTBR1 address corresponds with the + * pgdir entry that covers the lowest 48-bit addressable VA. + * + * Note that this trick is only used for LVA/64k pages - LPA2/4k pages uses an + * additional paging level, and on LPA2/16k pages, we would end up with a root + * level table with only 2 entries, which is suboptimal in terms of TLB + * utilization, so there we fall back to 47 bits of translation if LPA2 is not + * supported. + * * orr is used as it can cover the immediate value (and is idempotent). - * In future this may be nop'ed out when dealing with 52-bit kernel VAs. * ttbr: Value of ttbr to set, modified. */ .macro offset_ttbr1, ttbr, tmp -#ifdef CONFIG_ARM64_VA_BITS_52 - mrs_s \tmp, SYS_ID_AA64MMFR2_EL1 - and \tmp, \tmp, #(0xf << ID_AA64MMFR2_LVA_SHIFT) - cbnz \tmp, .Lskipoffs_\@ - orr \ttbr, \ttbr, #TTBR1_BADDR_4852_OFFSET -.Lskipoffs_\@ : -#endif - .endm - -/* - * Perform the reverse of offset_ttbr1. - * bic is used as it can cover the immediate value and, in future, won't need - * to be nop'ed out when dealing with 52-bit kernel VAs. - */ - .macro restore_ttbr1, ttbr -#ifdef CONFIG_ARM64_VA_BITS_52 - bic \ttbr, \ttbr, #TTBR1_BADDR_4852_OFFSET +#if defined(CONFIG_ARM64_VA_BITS_52) && !defined(CONFIG_ARM64_LPA2) + mrs \tmp, tcr_el1 + and \tmp, \tmp, #TCR_T1SZ_MASK + cmp \tmp, #TCR_T1SZ(VA_BITS_MIN) + orr \tmp, \ttbr, #TTBR1_BADDR_4852_OFFSET + csel \ttbr, \tmp, \ttbr, eq #endif .endm @@ -648,27 +614,13 @@ alternative_endif .macro phys_to_pte, pte, phys #ifdef CONFIG_ARM64_PA_BITS_52 - /* - * We assume \phys is 64K aligned and this is guaranteed by only - * supporting this configuration with 64K pages. - */ - orr \pte, \phys, \phys, lsr #36 - and \pte, \pte, #PTE_ADDR_MASK + orr \pte, \phys, \phys, lsr #PTE_ADDR_HIGH_SHIFT + and \pte, \pte, #PHYS_TO_PTE_ADDR_MASK #else mov \pte, \phys #endif .endm - .macro pte_to_phys, phys, pte -#ifdef CONFIG_ARM64_PA_BITS_52 - ubfiz \phys, \pte, #(48 - 16 - 12), #16 - bfxil \phys, \pte, #16, #32 - lsl \phys, \phys, #16 -#else - and \phys, \pte, #PTE_ADDR_MASK -#endif - .endm - /* * tcr_clear_errata_bits - Clear TCR bits that trigger an errata on this CPU. */ @@ -787,32 +739,25 @@ alternative_endif .endm /* - * Check whether preempt/bh-disabled asm code should yield as soon as - * it is able. This is the case if we are currently running in task - * context, and either a softirq is pending, or the TIF_NEED_RESCHED - * flag is set and re-enabling preemption a single time would result in - * a preempt count of zero. (Note that the TIF_NEED_RESCHED flag is - * stored negated in the top word of the thread_info::preempt_count + * Check whether asm code should yield as soon as it is able. This is + * the case if we are currently running in task context, and the + * TIF_NEED_RESCHED flag is set. (Note that the TIF_NEED_RESCHED flag + * is stored negated in the top word of the thread_info::preempt_count * field) */ - .macro cond_yield, lbl:req, tmp:req, tmp2:req + .macro cond_yield, lbl:req, tmp:req, tmp2 +#ifdef CONFIG_PREEMPT_VOLUNTARY get_current_task \tmp ldr \tmp, [\tmp, #TSK_TI_PREEMPT] /* * If we are serving a softirq, there is no point in yielding: the * softirq will not be preempted no matter what we do, so we should - * run to completion as quickly as we can. + * run to completion as quickly as we can. The preempt_count field will + * have BIT(SOFTIRQ_SHIFT) set in this case, so the zero check will + * catch this case too. */ - tbnz \tmp, #SOFTIRQ_SHIFT, .Lnoyield_\@ -#ifdef CONFIG_PREEMPTION - sub \tmp, \tmp, #PREEMPT_DISABLE_OFFSET cbz \tmp, \lbl #endif - adr_l \tmp, irq_stat + IRQ_CPUSTAT_SOFTIRQ_PENDING - get_this_cpu_offset \tmp2 - ldr w\tmp, [\tmp, \tmp2] - cbnz w\tmp, \lbl // yield on pending softirq in task context -.Lnoyield_\@: .endm /* @@ -877,7 +822,7 @@ alternative_endif .macro __mitigate_spectre_bhb_loop tmp #ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY -alternative_cb spectre_bhb_patch_loop_iter +alternative_cb ARM64_ALWAYS_SYSTEM, spectre_bhb_patch_loop_iter mov \tmp, #32 // Patched to correct the immediate alternative_cb_end .Lspectre_bhb_loop\@: @@ -890,7 +835,7 @@ alternative_cb_end .macro mitigate_spectre_bhb_loop tmp #ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY -alternative_cb spectre_bhb_patch_loop_mitigation_enable +alternative_cb ARM64_ALWAYS_SYSTEM, spectre_bhb_patch_loop_mitigation_enable b .L_spectre_bhb_loop_done\@ // Patched to NOP alternative_cb_end __mitigate_spectre_bhb_loop \tmp @@ -904,7 +849,7 @@ alternative_cb_end stp x0, x1, [sp, #-16]! stp x2, x3, [sp, #-16]! mov w0, #ARM_SMCCC_ARCH_WORKAROUND_3 -alternative_cb smccc_patch_fw_mitigation_conduit +alternative_cb ARM64_ALWAYS_SYSTEM, smccc_patch_fw_mitigation_conduit nop // Patched to SMC/HVC #0 alternative_cb_end ldp x2, x3, [sp], #16 @@ -914,7 +859,7 @@ alternative_cb_end .macro mitigate_spectre_bhb_clear_insn #ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY -alternative_cb spectre_bhb_patch_clearbhb +alternative_cb ARM64_ALWAYS_SYSTEM, spectre_bhb_patch_clearbhb /* Patched to NOP when not supported */ clearbhb isb |