linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Mark Rutland <mark.rutland@arm.com>
To: linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, will.deacon@arm.com,
	catalin.marinas@arm.com
Cc: Mark Rutland <mark.rutland@arm.com>, James Morse <james.morse@arm.com>
Subject: [PATCHv2 02/19] arm64: move SCTLR_EL{1,2} assertions to <asm/sysreg.h>
Date: Fri,  1 Jun 2018 12:24:24 +0100	[thread overview]
Message-ID: <20180601112441.37810-3-mark.rutland@arm.com> (raw)
In-Reply-To: <20180601112441.37810-1-mark.rutland@arm.com>

Currently we assert that the SCTLR_EL{1,2}_{SET,CLEAR} bits are
self-consistent with an assertion in config_sctlr_el1(). This is a bit
unusual, since config_sctlr_el1() doesn't make use of these definitions,
and is far away from the definitions themselves.

We can use the CPP #error directive to have equivalent assertions in
<asm/sysreg.h>, next to the definitions of the set/clear bits, which is
a bit clearer and simpler.

The preprocessor handles literals differently than regular C, e.g. ~0 is
equivalent to ~(intmax_t)0 rather than ~(int)0. Therefore, instead of ~0
we use 0xffffffff, which is unambiguous.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
---
 arch/arm64/include/asm/sysreg.h | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 6171178075dc..bd1d1194a5e7 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -452,9 +452,9 @@
 			 SCTLR_ELx_SA     | SCTLR_ELx_I    | SCTLR_ELx_WXN | \
 			 ENDIAN_CLEAR_EL2 | SCTLR_EL2_RES0)
 
-/* Check all the bits are accounted for */
-#define SCTLR_EL2_BUILD_BUG_ON_MISSING_BITS	BUILD_BUG_ON((SCTLR_EL2_SET ^ SCTLR_EL2_CLEAR) != ~0)
-
+#if (SCTLR_EL2_SET ^ SCTLR_EL2_CLEAR) != 0xffffffff
+#error "Inconsistent SCTLR_EL2 set/clear bits"
+#endif
 
 /* SCTLR_EL1 specific flags. */
 #define SCTLR_EL1_UCI		(1 << 26)
@@ -492,8 +492,9 @@
 			 SCTLR_EL1_UMA | SCTLR_ELx_WXN     | ENDIAN_CLEAR_EL1 |\
 			 SCTLR_EL1_RES0)
 
-/* Check all the bits are accounted for */
-#define SCTLR_EL1_BUILD_BUG_ON_MISSING_BITS	BUILD_BUG_ON((SCTLR_EL1_SET ^ SCTLR_EL1_CLEAR) != ~0)
+#if (SCTLR_EL1_SET ^ SCTLR_EL1_CLEAR) != 0xffffffff
+#error "Inconsistent SCTLR_EL1 set/clear bits"
+#endif
 
 /* id_aa64isar0 */
 #define ID_AA64ISAR0_TS_SHIFT		52
@@ -732,9 +733,6 @@ static inline void config_sctlr_el1(u32 clear, u32 set)
 {
 	u32 val;
 
-	SCTLR_EL2_BUILD_BUG_ON_MISSING_BITS;
-	SCTLR_EL1_BUILD_BUG_ON_MISSING_BITS;
-
 	val = read_sysreg(sctlr_el1);
 	val &= ~clear;
 	val |= set;
-- 
2.11.0

  parent reply	other threads:[~2018-06-01 11:29 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-06-01 11:24 [PATCHv2 00/19] arm64: invoke syscalls with pt_regs Mark Rutland
2018-06-01 11:24 ` [PATCHv2 01/19] arm64: consistently use unsigned long for thread flags Mark Rutland
2018-06-01 11:24 ` Mark Rutland [this message]
2018-06-14 16:44   ` [PATCHv2 02/19] arm64: move SCTLR_EL{1,2} assertions to <asm/sysreg.h> Will Deacon
2018-06-01 11:24 ` [PATCHv2 03/19] arm64: introduce sysreg_clear_set() Mark Rutland
2018-06-01 11:24 ` [PATCHv2 04/19] arm64: kill config_sctlr_el1() Mark Rutland
2018-06-01 11:24 ` [PATCHv2 05/19] arm64: kill change_cpacr() Mark Rutland
2018-06-01 11:24 ` [PATCHv2 06/19] arm64: move sve_user_{enable,disable} to <asm/fpsimd.h> Mark Rutland
2018-06-01 11:24 ` [PATCHv2 07/19] arm64: remove sigreturn wrappers Mark Rutland
2018-06-01 11:24 ` [PATCHv2 08/19] arm64: convert raw syscall invocation to C Mark Rutland
2018-06-01 11:24 ` [PATCHv2 09/19] arm64: convert syscall trace logic " Mark Rutland
2018-06-01 11:24 ` [PATCHv2 10/19] arm64: convert native/compat syscall entry " Mark Rutland
2018-06-01 11:24 ` [PATCHv2 11/19] arm64: don't reload GPRs after apply_ssbd Mark Rutland
2018-06-01 14:41   ` Marc Zyngier
2018-06-01 11:24 ` [PATCHv2 12/19] arm64: zero GPRs upon entry from EL0 Mark Rutland
2018-06-01 11:24 ` [PATCHv2 13/19] kernel: add ksys_personality() Mark Rutland
2018-06-01 11:24 ` [PATCHv2 14/19] kernel: add kcompat_sys_{f,}statfs64() Mark Rutland
2018-06-01 11:24 ` [PATCHv2 15/19] arm64: remove in-kernel call to sys_personality() Mark Rutland
2018-06-01 11:24 ` [PATCHv2 16/19] arm64: use {COMPAT,}SYSCALL_DEFINE0 for sigreturn Mark Rutland
2018-06-01 11:24 ` [PATCHv2 17/19] arm64: use SYSCALL_DEFINE6() for mmap Mark Rutland
2018-06-01 11:24 ` [PATCHv2 18/19] arm64: convert compat wrappers to C Mark Rutland
2018-06-01 11:24 ` [PATCHv2 19/19] arm64: implement syscall wrappers Mark Rutland

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180601112441.37810-3-mark.rutland@arm.com \
    --to=mark.rutland@arm.com \
    --cc=catalin.marinas@arm.com \
    --cc=james.morse@arm.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=will.deacon@arm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).