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Diffstat (limited to 'arch/arm64/include/asm/assembler.h')
-rw-r--r--arch/arm64/include/asm/assembler.h130
1 files changed, 51 insertions, 79 deletions
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h
index 376a980f2bad..f0ca7196f6fa 100644
--- a/arch/arm64/include/asm/assembler.h
+++ b/arch/arm64/include/asm/assembler.h
@@ -5,14 +5,14 @@
* Copyright (C) 1996-2000 Russell King
* Copyright (C) 2012 ARM Ltd.
*/
-#ifndef __ASSEMBLY__
+#ifndef __ASSEMBLER__
#error "Only include this from assembly code"
#endif
#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>
@@ -38,13 +38,14 @@
msr daifset, #0xf
.endm
- .macro enable_daif
- msr daifclr, #0xf
- .endm
-
/*
* Save/restore interrupts.
*/
+ .macro save_and_disable_daif, flags
+ mrs \flags, daif
+ msr daifset, #0xf
+ .endm
+
.macro save_and_disable_irq, flags
mrs \flags, daif
msr daifset, #3
@@ -54,16 +55,12 @@
msr daif, \flags
.endm
- .macro enable_dbg
- msr daifclr, #8
- .endm
-
.macro disable_step_tsk, flgs, tmp
tbz \flgs, #TIF_SINGLESTEP, 9990f
mrs \tmp, mdscr_el1
- bic \tmp, \tmp, #DBG_MDSCR_SS
+ bic \tmp, \tmp, #MDSCR_EL1_SS
msr mdscr_el1, \tmp
- isb // Synchronise with enable_dbg
+ isb // Take effect before a subsequent clear of DAIF.D
9990:
.endm
@@ -71,7 +68,7 @@
.macro enable_step_tsk, flgs, tmp
tbz \flgs, #TIF_SINGLESTEP, 9990f
mrs \tmp, mdscr_el1
- orr \tmp, \tmp, #DBG_MDSCR_SS
+ orr \tmp, \tmp, #MDSCR_EL1_SS
msr mdscr_el1, \tmp
9990:
.endm
@@ -257,13 +254,6 @@ alternative_endif
.endm
/*
- * vma_vm_mm - get mm pointer from vma pointer (vma->vm_mm)
- */
- .macro vma_vm_mm, rd, rn
- ldr \rd, [\rn, #VMA_VM_MM]
- .endm
-
-/*
* read_ctr - read CTR_EL0. If the system has mismatched register fields,
* provide the system wide safe value from arm64_ftr_reg_ctrel0.sys_val
*/
@@ -335,28 +325,14 @@ alternative_cb_end
* tcr_set_t0sz - update TCR.T0SZ so that we can load the ID map
*/
.macro tcr_set_t0sz, valreg, t0sz
- bfi \valreg, \t0sz, #TCR_T0SZ_OFFSET, #TCR_TxSZ_WIDTH
+ bfi \valreg, \t0sz, #TCR_EL1_T0SZ_SHIFT, #TCR_EL1_T0SZ_WIDTH
.endm
/*
* tcr_set_t1sz - update TCR.T1SZ
*/
.macro tcr_set_t1sz, valreg, t1sz
- bfi \valreg, \t1sz, #TCR_T1SZ_OFFSET, #TCR_TxSZ_WIDTH
- .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
+ bfi \valreg, \t1sz, #TCR_EL1_T1SZ_SHIFT, #TCR_EL1_T1SZ_WIDTH
.endm
/*
@@ -372,6 +348,11 @@ alternative_cb_end
// Narrow PARange to fit the PS field in TCR_ELx
ubfx \tmp0, \tmp0, #ID_AA64MMFR0_EL1_PARANGE_SHIFT, #3
mov \tmp1, #ID_AA64MMFR0_EL1_PARANGE_MAX
+#ifdef CONFIG_ARM64_LPA2
+alternative_if_not ARM64_HAS_VA52
+ mov \tmp1, #ID_AA64MMFR0_EL1_PARANGE_48
+alternative_else_nop_endif
+#endif
cmp \tmp0, \tmp1
csel \tmp0, \tmp1, \tmp0, hi
bfi \tcr, \tmp0, \pos, #3
@@ -390,7 +371,7 @@ alternative_endif
* [start, end) with dcache line size explicitly provided.
*
* op: operation passed to dc instruction
- * domain: domain used in dsb instruciton
+ * domain: domain used in dsb instruction
* start: starting virtual address of the region
* end: end virtual address of the region
* linesz: dcache line size
@@ -431,7 +412,7 @@ alternative_endif
* [start, end)
*
* op: operation passed to dc instruction
- * domain: domain used in dsb instruciton
+ * domain: domain used in dsb instruction
* start: starting virtual address of the region
* end: end virtual address of the region
* fixup: optional label to branch to on user fault
@@ -498,9 +479,10 @@ alternative_endif
*/
.macro reset_pmuserenr_el0, tmpreg
mrs \tmpreg, id_aa64dfr0_el1
- sbfx \tmpreg, \tmpreg, #ID_AA64DFR0_EL1_PMUVer_SHIFT, #4
- cmp \tmpreg, #1 // Skip if no PMU present
- b.lt 9000f
+ ubfx \tmpreg, \tmpreg, #ID_AA64DFR0_EL1_PMUVer_SHIFT, #4
+ cmp \tmpreg, #ID_AA64DFR0_EL1_PMUVer_NI
+ ccmp \tmpreg, #ID_AA64DFR0_EL1_PMUVer_IMP_DEF, #4, ne
+ b.eq 9000f // Skip if no PMU present or IMP_DEF
msr pmuserenr_el0, xzr // Disable PMU access from EL0
9000:
.endm
@@ -590,18 +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_EL1_VARange_SHIFT)
- cbnz \tmp, .Lskipoffs_\@
- orr \ttbr, \ttbr, #TTBR1_BADDR_4852_OFFSET
-.Lskipoffs_\@ :
+#if defined(CONFIG_ARM64_VA_BITS_52) && !defined(CONFIG_ARM64_LPA2)
+ mrs \tmp, tcr_el1
+ and \tmp, \tmp, #TCR_EL1_T1SZ_MASK
+ cmp \tmp, #TCR_T1SZ(VA_BITS_MIN)
+ orr \tmp, \ttbr, #TTBR1_BADDR_4852_OFFSET
+ csel \ttbr, \tmp, \ttbr, eq
#endif
.endm
@@ -623,25 +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
- and \phys, \pte, #PTE_ADDR_MASK
-#ifdef CONFIG_ARM64_PA_BITS_52
- orr \phys, \phys, \phys, lsl #PTE_ADDR_HIGH_SHIFT
- and \phys, \phys, GENMASK_ULL(PHYS_MASK_SHIFT - 1, PAGE_SHIFT)
-#endif
- .endm
-
/*
* tcr_clear_errata_bits - Clear TCR bits that trigger an errata on this CPU.
*/
@@ -760,32 +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
/*