[RFC,09/13] ARC: delay: elide ZOL

Message ID	20220222141506.4003433-10-geomatsi@gmail.com
State	New
Headers	show Return-Path: <linux-snps-arc-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org> From: Sergey Matyukevich <geomatsi@gmail.com> To: linux-snps-arc@lists.infradead.org Cc: Vineet Gupta <vgupta@kernel.org>, Vladimir Isaev <isaev@synopsys.com>, Sergey Matyukevich <geomatsi@gmail.com>, Sergey Matyukevich <sergey.matyukevich@synopsys.com> Subject: [RFC PATCH 09/13] ARC: delay: elide ZOL Date: Tue, 22 Feb 2022 17:15:02 +0300 Message-Id: <20220222141506.4003433-10-geomatsi@gmail.com> In-Reply-To: <20220222141506.4003433-1-geomatsi@gmail.com> References: <20220222141506.4003433-1-geomatsi@gmail.com> MIME-Version: 1.0 preview: From: Vineet Gupta Add __delay implementation based on DBNZ if ZOL is not supported. Signed-off-by: Vineet Gupta --- arch/arc/include/asm/delay.h \| 16 ++++++++++++++++ 1 file changed, 16 insertions(+) Content analysis details: (-0.2 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [2a00:1450:4864:20:0:0:0:234 listed in] [list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider [geomatsi[at]gmail.com] -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain Precedence: list Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-snps-arc" <linux-snps-arc-bounces@lists.infradead.org> Errors-To: linux-snps-arc-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org
Series	ARC: handle the lack of ZOL support \| expand [RFC,00/13] ARC: handle the lack of ZOL support [RFC,01/13] ARC: uaccess: elide unaligned handling if hardware supports [RFC,02/13] ARC: Kconfig: introduce option to disable ZOL [RFC,03/13] ARC: uaccess: drop CC_OPTIMIZE_FOR_SIZE [RFC,04/13] ARC: uaccess: elide ZOL, use double load/stores [RFC,05/13] ARCv2: memset: don't prefetch for len == 0 which happens a lot [RFC,06/13] ARCv2: memset: elide unaligned handling if hardware supports [RFC,07/13] ARCv2: memset: rewrite using double load/stores [RFC,08/13] ARC: string: use generic C code if no ZOL support [RFC,09/13] ARC: delay: elide ZOL [RFC,10/13] ARC: checksum: elide ZOL [RFC,11/13] ARC: head: elide ZOL [RFC,12/13] ARC: build: inhibit ZOL generation by compiler [RFC,13/13] ARC: pt_regs: handle the case when ZOL is not supported

Message ID

20220222141506.4003433-10-geomatsi@gmail.com

State

New

Headers

From: Sergey Matyukevich <geomatsi@gmail.com>
To: linux-snps-arc@lists.infradead.org
Cc: Vineet Gupta <vgupta@kernel.org>, Vladimir Isaev <isaev@synopsys.com>,
 Sergey Matyukevich <geomatsi@gmail.com>,
 Sergey Matyukevich <sergey.matyukevich@synopsys.com>
Subject: [RFC PATCH 09/13] ARC: delay: elide ZOL
Date: Tue, 22 Feb 2022 17:15:02 +0300
Message-Id: <20220222141506.4003433-10-geomatsi@gmail.com>
In-Reply-To: <20220222141506.4003433-1-geomatsi@gmail.com>
References: <20220222141506.4003433-1-geomatsi@gmail.com>
MIME-Version: 1.0
Precedence: list
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Sender: "linux-snps-arc" <linux-snps-arc-bounces@lists.infradead.org>
Errors-To: 
 linux-snps-arc-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org

Series

ARC: handle the lack of ZOL support | expand

Commit Message

Sergey Matyukevich Feb. 22, 2022, 2:15 p.m. UTC

From: Vineet Gupta <vgupta@kernel.org>

Add __delay implementation based on DBNZ if ZOL is not supported.

Signed-off-by: Vineet Gupta <vgupta@kernel.org>
---
 arch/arc/include/asm/delay.h | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/arch/arc/include/asm/delay.h b/arch/arc/include/asm/delay.h
index 54db798f0aa0..e061d1c64f24 100644
--- a/arch/arc/include/asm/delay.h
+++ b/arch/arc/include/asm/delay.h
@@ -16,9 +16,12 @@ 
 
 #include <asm-generic/types.h>
 #include <asm/param.h>		/* HZ */
+#include <asm/assembler.h>
 
 extern unsigned long loops_per_jiffy;
 
+#ifndef CONFIG_ARC_LACKS_ZOL
+
 static inline void __delay(unsigned long loops)
 {
 	__asm__ __volatile__(
@@ -31,6 +34,19 @@  static inline void __delay(unsigned long loops)
         : "lp_count");
 }
 
+#else
+
+static inline void __delay(unsigned long loops)
+{
+	__asm__ __volatile__(
+	"	add   %0, %0, 1         \n"
+	"1:	nop			\n"
+	"	DBNZR %0, 1b		\n"
+	: "+r"(loops));
+}
+
+#endif
+
 extern void __bad_udelay(void);
 
 /*

[RFC,09/13] ARC: delay: elide ZOL

Commit Message

Patch