[boot-wrapper PATCH 04/12] Remove `flag_no_el3`
From: Mark Rutland <mark.rutland@arm.com>
Date: 2021-07-29 15:26:01
Subsystem:
the rest · Maintainer:
Linus Torvalds
We set `flag_no_el3` when not booted at EL3 / monitor mode, and subsequently we use this to determine whether we need to drop exception level before entering Linux. As this can be derived from CurrentEL or CPSR, the flag itself is redundant, and we can defer the check until we're about to enter Linux. In future this will allow more logic to be converted into C, where it will be easier to handle architectural variants. Signed-off-by: Mark Rutland <mark.rutland@arm.com> --- arch/aarch32/boot.S | 14 +++----------- arch/aarch64/boot.S | 13 ++----------- 2 files changed, 5 insertions(+), 22 deletions(-)
diff --git a/arch/aarch32/boot.S b/arch/aarch32/boot.S
index 2a85ad5..0bd1ca2 100644
--- a/arch/aarch32/boot.S
+++ b/arch/aarch32/boot.S@@ -31,9 +31,6 @@ ENTRY(_start) cmp r0, #PSR_HYP bne _switch_monitor - mov r0, #1 - ldr r1, =flag_no_el3 - str r0, [r1] b start_no_el3 _switch_monitor:
@@ -89,9 +86,9 @@ ENTRY(jump_kernel) ldr lr, [r5], #4 ldm r5, {r0 - r2} - ldr r4, =flag_no_el3 - ldr r4, [r4] - cmp r4, #1 + mrs r4, cpsr + and r4, #PSR_MODE_MASK + cmp r4, #PSR_MON bxeq lr @ no EL3 ldr r4, =SPSR_KERNEL
@@ -113,8 +110,3 @@ boot_vectors: b . b . b . - - .section .data - .align 2 -flag_no_el3: - .long 0
diff --git a/arch/aarch64/boot.S b/arch/aarch64/boot.S
index 37759ce..fae0188 100644
--- a/arch/aarch64/boot.S
+++ b/arch/aarch64/boot.S@@ -28,10 +28,6 @@ _start: cmp x0, #CURRENTEL_EL3 b.eq 1f - mov w0, #1 - ldr x1, =flag_no_el3 - str w0, [x1] - b start_no_el3 1: mov x0, #0x30 // RES1
@@ -140,8 +136,8 @@ jump_kernel: bl find_logical_id bl setup_stack // Reset stack pointer - ldr w0, flag_no_el3 - cmp w0, #0 // Prepare Z flag + mrs x0, CurrentEl + cmp w0, #CURRENTEL_EL3 // Prepare Z flag mov x0, x20 mov x1, x21
@@ -164,8 +160,3 @@ jump_kernel: eret .ltorg - - .data - .align 3 -flag_no_el3: - .long 0
--
2.11.0
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