Commit 7ddb0c3d authored by Marc Zyngier's avatar Marc Zyngier Committed by Will Deacon
Browse files

arm64: Rename the VHE switch to "finalise_el2" 



as we are about to perform a lot more in 'mutate_to_vhe' than
we currently do, this function really becomes the point where
we finalise the basic EL2 configuration.

Reflect this into the code by renaming a bunch of things:
- HVC_VHE_RESTART -> HVC_FINALISE_EL2
- switch_to_vhe --> finalise_el2
- mutate_to_vhe -> __finalise_el2

No functional changes.

Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220630160500.1536744-2-maz@kernel.org


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent 0aaa6853

Documentation/virt/kvm/arm/hyp-abi.rst

+6 −5
Original line number Diff line number Diff line
@@ -60,12 +60,13 @@ these functions (see arch/arm{,64}/include/asm/virt.h): 


* ::



    x0 = HVC_VHE_RESTART (arm64 only)

    x0 = HVC_FINALISE_EL2 (arm64 only)



  Attempt to upgrade the kernel's exception level from EL1 to EL2 by enabling

  the VHE mode. This is conditioned by the CPU supporting VHE, the EL2 MMU

  being off, and VHE not being disabled by any other means (command line

  option, for example).

  Finish configuring EL2 depending on the command-line options,

  including an attempt to upgrade the kernel's exception level from

  EL1 to EL2 by enabling the VHE mode. This is conditioned by the CPU

  supporting VHE, the EL2 MMU being off, and VHE not being disabled by

  any other means (command line option, for example).



Any other value of r0/x0 triggers a hypervisor-specific handling,

which is not documented here.

arch/arm64/include/asm/virt.h

+2 −2
Original line number Diff line number Diff line
@@ -36,9 +36,9 @@ 
#define HVC_RESET_VECTORS 2



/*

 * HVC_VHE_RESTART - Upgrade the CPU from EL1 to EL2, if possible

 * HVC_FINALISE_EL2 - Upgrade the CPU from EL1 to EL2, if possible

 */

#define HVC_VHE_RESTART	3

#define HVC_FINALISE_EL2	3



/* Max number of HYP stub hypercalls */

#define HVC_STUB_HCALL_NR 4

arch/arm64/kernel/head.S

+3 −3
Original line number Diff line number Diff line
@@ -459,7 +459,7 @@ SYM_FUNC_START_LOCAL(__primary_switched) 
	mov	x0, x22				// pass FDT address in x0

	bl	init_feature_override		// Parse cpu feature overrides

	mov	x0, x20

	bl	switch_to_vhe			// Prefer VHE if possible

	bl	finalise_el2			// Prefer VHE if possible

	ldp	x29, x30, [sp], #16

	bl	start_kernel

	ASM_BUG()
@@ -542,7 +542,7 @@ SYM_INNER_LABEL(init_el2, SYM_L_LOCAL) 
	eret



__cpu_stick_to_vhe:

	mov	x0, #HVC_VHE_RESTART

	mov	x0, #HVC_FINALISE_EL2

	hvc	#0

	mov	x0, #BOOT_CPU_MODE_EL2

	ret
@@ -592,7 +592,7 @@ SYM_FUNC_START_LOCAL(secondary_startup) 
	 * Common entry point for secondary CPUs.

	 */

	mov	x20, x0				// preserve boot mode

	bl	switch_to_vhe

	bl	finalise_el2

	bl	__cpu_secondary_check52bitva

#if VA_BITS > 48

	ldr_l	x0, vabits_actual

arch/arm64/kernel/hyp-stub.S

+10 −11
Original line number Diff line number Diff line
@@ -51,8 +51,8 @@ SYM_CODE_START_LOCAL(elx_sync) 
	msr	vbar_el2, x1

	b	9f



1:	cmp	x0, #HVC_VHE_RESTART

	b.eq	mutate_to_vhe

1:	cmp	x0, #HVC_FINALISE_EL2

	b.eq	__finalise_el2



2:	cmp	x0, #HVC_SOFT_RESTART

	b.ne	3f
@@ -73,8 +73,8 @@ SYM_CODE_START_LOCAL(elx_sync) 
	eret

SYM_CODE_END(elx_sync)



SYM_CODE_START_LOCAL(__finalise_el2)

	// nVHE? No way! Give me the real thing!

SYM_CODE_START_LOCAL(mutate_to_vhe)

	// Sanity check: MMU *must* be off

	mrs	x1, sctlr_el2

	tbnz	x1, #0, 1f
@@ -140,10 +140,10 @@ SYM_CODE_START_LOCAL(mutate_to_vhe) 
	msr	spsr_el1, x0



	b	enter_vhe

SYM_CODE_END(mutate_to_vhe)

SYM_CODE_END(__finalise_el2)



	// At the point where we reach enter_vhe(), we run with

	// the MMU off (which is enforced by mutate_to_vhe()).

	// the MMU off (which is enforced by __finalise_el2()).

	// We thus need to be in the idmap, or everything will

	// explode when enabling the MMU.
@@ -222,11 +222,11 @@ SYM_FUNC_START(__hyp_reset_vectors) 
SYM_FUNC_END(__hyp_reset_vectors)



/*

 * Entry point to switch to VHE if deemed capable

 * Entry point to finalise EL2 and switch to VHE if deemed capable

 *

 * w0: boot mode, as returned by init_kernel_el()

 */

SYM_FUNC_START(switch_to_vhe)

SYM_FUNC_START(finalise_el2)

	// Need to have booted at EL2

	cmp	w0, #BOOT_CPU_MODE_EL2

	b.ne	1f
@@ -236,9 +236,8 @@ SYM_FUNC_START(switch_to_vhe) 
	cmp	x0, #CurrentEL_EL1

	b.ne	1f



	// Turn the world upside down

	mov	x0, #HVC_VHE_RESTART

	mov	x0, #HVC_FINALISE_EL2

	hvc	#0

1:

	ret

SYM_FUNC_END(switch_to_vhe)
 
SYM_FUNC_END(finalise_el2)

arch/arm64/kernel/sleep.S

+1 −1
Original line number Diff line number Diff line
@@ -100,7 +100,7 @@ SYM_FUNC_END(__cpu_suspend_enter) 
	.pushsection ".idmap.text", "awx"

SYM_CODE_START(cpu_resume)

	bl	init_kernel_el

	bl	switch_to_vhe

	bl	finalise_el2

	bl	__cpu_setup

	/* enable the MMU early - so we can access sleep_save_stash by va */

	adrp	x1, swapper_pg_dir