From: Ard Biesheuvel <ardb@kernel.org>
To: linux-efi@vger.kernel.org
Cc: Nicolas Pitre <nico@fluxnic.net>, Marc Zyngier <maz@kernel.org>,
Linus Walleij <linus.walleij@linaro.org>,
Nick Desaulniers <ndesaulniers@google.com>,
Russell King <linux@armlinux.org.uk>,
Stefan Agner <stefan@agner.ch>, Peter Smith <Peter.Smith@arm.com>,
Will Deacon <will@kernel.org>, Ard Biesheuvel <ardb@kernel.org>,
linux-arm-kernel@lists.infradead.org
Subject: [PATCH 06/12] ARM: head.S: use PC-relative insn sequence for secondary_data
Date: Mon, 14 Sep 2020 12:57:00 +0300 [thread overview]
Message-ID: <20200914095706.3985-7-ardb@kernel.org> (raw)
In-Reply-To: <20200914095706.3985-1-ardb@kernel.org>
Replace the open coded PC relative offset calculations with adr_l
and ldr_l invocations. This removes some open coded arithmetic
involving virtual addresses, avoids literal pools on v7+, and slightly
reduces the footprint of the code.
Note that it also removes a stale comment about the contents of r6.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
arch/arm/kernel/head.S | 19 ++++---------------
1 file changed, 4 insertions(+), 15 deletions(-)
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 7d8e2a296216..40407a4727e0 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -383,10 +383,8 @@ ENTRY(secondary_startup)
/*
* Use the page tables supplied from __cpu_up.
*/
- adr r4, __secondary_data
- ldmia r4, {r5, r7, r12} @ address to jump to after
- sub lr, r4, r5 @ mmu has been enabled
- add r3, r7, lr
+ adr_l r3, secondary_data
+ mov_l r12, __secondary_switched
ldrd r4, r5, [r3, #0] @ get secondary_data.pgdir
ARM_BE8(eor r4, r4, r5) @ Swap r5 and r4 in BE:
ARM_BE8(eor r5, r4, r5) @ it can be done in 3 steps
@@ -401,22 +399,13 @@ ARM_BE8(eor r4, r4, r5) @ without using a temp reg.
ENDPROC(secondary_startup)
ENDPROC(secondary_startup_arm)
- /*
- * r6 = &secondary_data
- */
ENTRY(__secondary_switched)
- ldr sp, [r7, #12] @ get secondary_data.stack
+ ldr_l r7, secondary_data + 12 @ get secondary_data.stack
+ mov sp, r7
mov fp, #0
b secondary_start_kernel
ENDPROC(__secondary_switched)
- .align
-
- .type __secondary_data, %object
-__secondary_data:
- .long .
- .long secondary_data
- .long __secondary_switched
#endif /* defined(CONFIG_SMP) */
--
2.17.1
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next prev parent reply other threads:[~2020-09-14 9:59 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-14 9:56 [PATCH 00/12] ARM: use adr_l/ldr_l macros for PC-relative references Ard Biesheuvel
2020-09-14 9:56 ` [PATCH 01/12] ARM: assembler: introduce adr_l, ldr_l and str_l macros Ard Biesheuvel
2020-09-15 7:35 ` Ard Biesheuvel
2020-09-15 17:51 ` Nick Desaulniers
2020-09-14 9:56 ` [PATCH 02/12] ARM: efistub: replace adrl pseudo-op with adr_l macro invocation Ard Biesheuvel
2020-09-14 9:56 ` [PATCH 03/12] ARM: module: add support for place relative relocations Ard Biesheuvel
2020-09-14 13:35 ` Nicolas Pitre
2020-09-14 16:11 ` Russell King - ARM Linux admin
2020-09-14 9:56 ` [PATCH 04/12] ARM: head-common.S: use PC-relative insn sequence for __proc_info Ard Biesheuvel
2020-09-14 9:56 ` [PATCH 05/12] ARM: head-common.S: use PC-relative insn sequence for idmap creation Ard Biesheuvel
2020-09-14 9:57 ` Ard Biesheuvel [this message]
2020-09-14 9:57 ` [PATCH 07/12] ARM: kernel: use relative references for UP/SMP alternatives Ard Biesheuvel
2020-09-14 9:57 ` [PATCH 08/12] ARM: head: use PC-relative insn sequence for __smp_alt Ard Biesheuvel
2020-09-14 9:57 ` [PATCH 09/12] ARM: sleep.S: use PC-relative insn sequence for sleep_save_sp/mpidr_hash Ard Biesheuvel
2020-09-14 9:57 ` [PATCH 10/12] ARM: head.S: use PC-relative insn sequences for __fixup_pv_table Ard Biesheuvel
2020-09-14 9:57 ` [PATCH 11/12] ARM: head.S: use PC relative insn sequence to calculate PHYS_OFFSET Ard Biesheuvel
2020-09-14 9:57 ` [PATCH 12/12] ARM: kvm: replace open coded VA->PA calculations with adr_l call Ard Biesheuvel
2020-09-14 14:06 ` [PATCH 00/12] ARM: use adr_l/ldr_l macros for PC-relative references Nicolas Pitre
2020-09-15 19:32 ` Nick Desaulniers
2020-09-15 21:29 ` Ard Biesheuvel
2020-09-15 23:31 ` Nick Desaulniers
2020-09-16 5:54 ` Ard Biesheuvel
2020-09-16 19:53 ` Nick Desaulniers
2020-09-16 20:45 ` Ard Biesheuvel
2020-09-16 21:25 ` Nick Desaulniers
2020-09-17 0:16 ` Nick Desaulniers
2020-09-17 5:19 ` Mike Rapoport
2020-09-17 6:01 ` Ard Biesheuvel
2020-09-18 20:03 ` Nick Desaulniers
2020-09-18 20:44 ` Ard Biesheuvel
2020-09-18 21:06 ` Nick Desaulniers
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