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ARM: ARMv7-M: implement restart routine common to all v7-M machines

PATCH Superseded Uwe Kleine-König 2 participants 3 messages Aug 15, 2013 Arm (32-bit)

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Uwe Kleine-König

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#0 lore raw

PATCH v2 1/1 ARM: ARMv7-M: implement restart routine common to all v7-M machines

The newly introduced function is to be used as .restart callback for ARMv7-M machines. The used register is architecturally defined, so it should work for all M-class machines.

Signed-off-by Uwe Kleine-K?nig <[email protected]>

---

Changes since v1, sent with Message-Id:
1376494625-25496-1-git-send-email-u.kleine-koenig at pengutronix.de:

- add a more verbose change log
- rename arch/arm/kernel/common-v7m.c to arch/arm/kernel/v7m.c

 arch/arm/include/asm/v7m.h | 12 ++++++++++++
 arch/arm/kernel/Makefile   |  2 +-
 arch/arm/kernel/v7m.c      | 19 +++++++++++++++++++
 3 files changed, 32 insertions(+), 1 deletion(-)
 create mode 100644 arch/arm/kernel/v7m.c
arch/arm/include/asm/v7m.h +12 -0
index fa88d09..615781c 100644
@@ -15,6 +15,10 @@
 
 #define V7M_SCB_VTOR			0x08
 
+#define V7M_SCB_AIRCR			0x0c
+#define V7M_SCB_AIRCR_VECTKEY			(0x05fa << 16)
+#define V7M_SCB_AIRCR_SYSRESETREQ		(1 << 2)
+
 #define V7M_SCB_SCR			0x10
 #define V7M_SCB_SCR_SLEEPDEEP			(1 << 2)
 

@@ -42,3 +46,11 @@
  */
 #define EXC_RET_STACK_MASK			0x00000004
 #define EXC_RET_THREADMODE_PROCESSSTACK		0xfffffffd
+
+#ifndef __ASSEMBLY__
+
+enum reboot_mode;
+
+void armv7m_restart(enum reboot_mode mode, const char *cmd);
+
+#endif /* __ASSEMBLY__ */
arch/arm/kernel/Makefile +1 -1
index 86d10dd..5140df5f 100644
@@ -24,7 +24,7 @@ obj-$(CONFIG_ATAGS_PROC)	+= atags_proc.o
 obj-$(CONFIG_DEPRECATED_PARAM_STRUCT) += atags_compat.o
 
 ifeq ($(CONFIG_CPU_V7M),y)
-obj-y		+= entry-v7m.o
+obj-y		+= entry-v7m.o v7m.o
 else
 obj-y		+= entry-armv.o
 endif
arch/arm/kernel/v7m.c new file +19 -0
new file mode 100644
index 0000000..4d2cba9
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2013 Uwe Kleine-Koenig for Pengutronix
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation.
+ */
+#include <linux/io.h>
+#include <linux/reboot.h>
+#include <asm/barrier.h>
+#include <asm/v7m.h>
+
+void armv7m_restart(enum reboot_mode mode, const char *cmd)
+{
+	dsb();
+	__raw_writel(V7M_SCB_AIRCR_VECTKEY | V7M_SCB_AIRCR_SYSRESETREQ,
+			BASEADDR_V7M_SCB + V7M_SCB_AIRCR);
+	dsb();
+}
Signature · 1 line
1.8.4.rc0
#1 lore raw

PATCH v2 1/1 ARM: ARMv7-M: implement restart routine common to all v7-M machines

Quoted 4 lines · Uwe Kleine-K?nig

The newly introduced function is to be used as .restart callback for ARMv7-M machines. The used register is architecturally defined, so it should work for all M-class machines.

Quoted 9 lines
Signed-off-by Uwe Kleine-K?nig <[email protected]>

---

Changes since v1, sent with Message-Id:
1376494625-25496-1-git-send-email-u.kleine-koenig at pengutronix.de:

- add a more verbose change log
- rename arch/arm/kernel/common-v7m.c to arch/arm/kernel/v7m.c

Thanks Uwe, this looks good now - assuming Russell's happy with arch/arm/kernel/v7m.c :)

FWIW,

Acked-by Jonathan Austin <[email protected]>
Quoted 72 lines
  arch/arm/include/asm/v7m.h | 12 ++++++++++++
  arch/arm/kernel/Makefile   |  2 +-
  arch/arm/kernel/v7m.c      | 19 +++++++++++++++++++
  3 files changed, 32 insertions(+), 1 deletion(-)

create mode 100644 arch/arm/kernel/v7m.c

arch/arm/include/asm/v7m.h +12 -0
index fa88d09..615781c 100644
@@ -15,6 +15,10 @@
 
  #define V7M_SCB_VTOR			0x08
 
+#define V7M_SCB_AIRCR			0x0c
+#define V7M_SCB_AIRCR_VECTKEY			(0x05fa << 16)
+#define V7M_SCB_AIRCR_SYSRESETREQ		(1 << 2)
+
  #define V7M_SCB_SCR			0x10
  #define V7M_SCB_SCR_SLEEPDEEP			(1 << 2)
 

@@ -42,3 +46,11 @@
   */
  #define EXC_RET_STACK_MASK			0x00000004
  #define EXC_RET_THREADMODE_PROCESSSTACK		0xfffffffd
+
+#ifndef __ASSEMBLY__
+
+enum reboot_mode;
+
+void armv7m_restart(enum reboot_mode mode, const char *cmd);
+
+#endif /* __ASSEMBLY__ */
arch/arm/kernel/Makefile +1 -1
index 86d10dd..5140df5f 100644
@@ -24,7 +24,7 @@ obj-$(CONFIG_ATAGS_PROC)	+= atags_proc.o
  obj-$(CONFIG_DEPRECATED_PARAM_STRUCT) += atags_compat.o
 
  ifeq ($(CONFIG_CPU_V7M),y)
-obj-y		+= entry-v7m.o
+obj-y		+= entry-v7m.o v7m.o
  else
  obj-y		+= entry-armv.o
  endif
arch/arm/kernel/v7m.c new file +19 -0
new file mode 100644
index 0000000..4d2cba9
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2013 Uwe Kleine-Koenig for Pengutronix
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation.
+ */
+#include <linux/io.h>
+#include <linux/reboot.h>
+#include <asm/barrier.h>
+#include <asm/v7m.h>
+
+void armv7m_restart(enum reboot_mode mode, const char *cmd)
+{
+	dsb();
+	__raw_writel(V7M_SCB_AIRCR_VECTKEY | V7M_SCB_AIRCR_SYSRESETREQ,
+			BASEADDR_V7M_SCB + V7M_SCB_AIRCR);
+	dsb();
+}
author
#2 lore raw

PATCH v2 1/1 ARM: ARMv7-M: implement restart routine common to all v7-M machines

Hello Russell,

Quoted 11 lines · Jonathan Austin
Quoted 10 lines · Uwe Kleine-K?nig

The newly introduced function is to be used as .restart callback for ARMv7-M machines. The used register is architecturally defined, so it should work for all M-class machines.

Signed-off-by Uwe Kleine-K?nig <[email protected]>

---

Changes since v1, sent with Message-Id:
1376494625-25496-1-git-send-email-u.kleine-koenig at pengutronix.de:

Quoted 6 lines
Quoted 3 lines

- add a more verbose change log
- rename arch/arm/kernel/common-v7m.c to arch/arm/kernel/v7m.c

Thanks Uwe, this looks good now - assuming Russell's happy with arch/arm/kernel/v7m.c :)

I'd like to get this patch, the efm32-clk patch (Message-Id:
1376510693-12491-1-git-send-email-u.kleine-koenig at pengutronix.de) and the patch introducing the efm32 platform (Message-Id:
1376552964-16296-1-git-send-email-u.kleine-koenig at pengutronix.de) merged for 3.12. So assuming you are OK with this change I'd like to let the arm-soc people pull the three patches from a single branch. For that I'd like to have you ack.

Best regards
Uwe

Signature · 2 lines
Pengutronix e.K.                           | Uwe Kleine-K?nig            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |