[PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1

[PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1

[Fabrizio Castro]

Dear All,

this series has been around for some time as RFC, and it has collected
useful comments from the community along the way.
The solution proposed by this patch set works for most R-Car Gen2 and
RZ/G1 devices, but not all of them. We now know that for some R-Car
Gen2 early revisions there is no proper software fix. Anyway, no
product has been built around early revisions, but development boards
mounting early revisions (basically prototypes) are still out there.
As a result, this series isn't enabling the internal watchdog on R-Car
Gen2 boards, developers may enable it in board specific device trees
if needed.
This series has been tested by me on the iwg20d, iwg22d, Lager, Alt,
and Koelsch boards.

The problem
===========
To deal with SMP on R-Car Gen2 and RZ/G1, we install a reset vector
to ICRAM1 and we program the [S]BAR registers so that when we turn ON
the non-boot CPUs they are redirected to the reset vector installed by
Linux in ICRAM1, and eventually they continue the execution to RAM,
where the SMP bring-up code will take care of the rest.
The content of the [S]BAR registers survives a watchdog triggered reset,
and as such after the watchdog fires the boot core will try and execute
the SMP bring-up code instead of jumping to the bootrom code.

The fix
=======
The main strategy for the solution is to let the reset vector decide
if it needs to jump to shmobile_boot_fn or to the bootrom code.
In a watchdog triggered reset scenario, since the [S]BAR registers keep
their values, the boot CPU will jump into the newly designed reset
vector, the assembly routine will eventually test WOVF (a bit in register
RWTCSRA that indicates if the watchdog counter has overflown, the value
of this bit gets retained in this scenario), and jump to the bootrom code
which will in turn load up the bootloader, etc.
When bringing up SMP or using CPU hotplug, the reset vector will jump
to shmobile_boot_fn instead.

Thank you All for your help.

Best regards,

Fabrizio Castro (26):
  ARM: shmobile: Add watchdog support
  ARM: dts: r8a7743: Adjust SMP routine size
  ARM: dts: r8a7745: Adjust SMP routine size
  ARM: dts: r8a7790: Adjust SMP routine size
  ARM: dts: r8a7791: Adjust SMP routine size
  ARM: dts: r8a7792: Adjust SMP routine size
  ARM: dts: r8a7793: Adjust SMP routine size
  ARM: dts: r8a7794: Adjust SMP routine size
  soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2
  ARM: shmobile: rcar-gen2: Add watchdog support
  dt-bindings: watchdog: renesas-wdt: Add R-Car Gen2 support
  watchdog: renesas_wdt: Add R-Car Gen2 support
  watchdog: renesas_wdt: Add restart handler
  ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN
  clk: renesas: r8a7743: Add rwdt clock
  clk: renesas: r8a7745: Add rwdt clock
  clk: renesas: r8a7790: Add rwdt clock
  clk: renesas: r8a7791/r8a7793: Add rwdt clock
  clk: renesas: r8a7794: Add rwdt clock
  ARM: dts: r8a7743: Add watchdog support to SoC dtsi
  ARM: dts: r8a7745: Add watchdog support to SoC dtsi
  ARM: dts: r8a7790: Add watchdog support to SoC dtsi
  ARM: dts: r8a7791: Add watchdog support to SoC dtsi
  ARM: dts: r8a7794: Add watchdog support to SoC dtsi
  ARM: dts: iwg20m: Add watchdog support to SoM dtsi
  ARM: dts: iwg22m: Add watchdog support to SoM dtsi

 .../devicetree/bindings/watchdog/renesas-wdt.txt   | 19 ++++++--
 arch/arm/boot/dts/r8a7743-iwg20m.dtsi              |  5 ++
 arch/arm/boot/dts/r8a7743.dtsi                     | 12 ++++-
 arch/arm/boot/dts/r8a7745-iwg22m.dtsi              |  5 ++
 arch/arm/boot/dts/r8a7745.dtsi                     | 12 ++++-
 arch/arm/boot/dts/r8a7790.dtsi                     | 12 ++++-
 arch/arm/boot/dts/r8a7791.dtsi                     | 12 ++++-
 arch/arm/boot/dts/r8a7792.dtsi                     |  2 +-
 arch/arm/boot/dts/r8a7793.dtsi                     |  2 +-
 arch/arm/boot/dts/r8a7794.dtsi                     | 12 ++++-
 arch/arm/configs/shmobile_defconfig                |  1 +
 arch/arm/mach-shmobile/common.h                    |  6 +++
 arch/arm/mach-shmobile/headsmp.S                   | 55 ++++++++++++++++++++++
 arch/arm/mach-shmobile/platsmp-apmu.c              |  1 +
 arch/arm/mach-shmobile/pm-rcar-gen2.c              | 15 ++++--
 drivers/clk/renesas/r8a7743-cpg-mssr.c             |  2 +
 drivers/clk/renesas/r8a7745-cpg-mssr.c             |  2 +
 drivers/clk/renesas/r8a7790-cpg-mssr.c             |  2 +
 drivers/clk/renesas/r8a7791-cpg-mssr.c             |  2 +
 drivers/clk/renesas/r8a7794-cpg-mssr.c             |  2 +
 drivers/soc/renesas/rcar-rst.c                     | 35 +++++++++++---
 drivers/watchdog/renesas_wdt.c                     | 39 +++++++++++++--
 22 files changed, 229 insertions(+), 26 deletions(-)

-- 
2.7.4

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[PATCH v5 01/26] ARM: shmobile: Add watchdog support

[Fabrizio Castro]

On R-Car Gen2 and RZ/G1 platforms, we use the SBAR registers to make non
boot CPUs run a routine designed to bring up SMP and deal with hot plug.
The value contained in the SBAR registers is not initialized by a WDT
triggered reset, which means that after a WDT triggered reset we jump
to the SMP bring up routine, preventing the system from executing the
bootrom code.

The purpose of this patch is to jump to the bootrom code in case of a
WDT triggered reset, and keep the SMP functionality untouched.
In order to tell if the code had been called due to the WDT overflowing
we are testing WOVF from register RWTCSRA.

The new function shmobile_boot_vector_gen2 isn't replacing
shmobile_boot_vector for backward compatibility reasons. The kernel
will install the best option (either shmobile_boot_vector or
shmobile_boot_vector_gen2) to ICRAM1 after parsing the device tree,
according to the amount of memory available.

Since shmobile_boot_vector has become bigger, "reg" property of nodes
compatible with "renesas,smp-sram" now need to be set to a value
greater or equal to "<0 0x60>".

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
---
v4->v5:
* no change

 arch/arm/mach-shmobile/common.h  |  6 +++++
 arch/arm/mach-shmobile/headsmp.S | 55 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 61 insertions(+)

diff --git a/arch/arm/mach-shmobile/common.h b/arch/arm/mach-shmobile/common.h
index a8fa4f7..d8c11f5 100644
--- a/arch/arm/mach-shmobile/common.h
+++ b/arch/arm/mach-shmobile/common.h
@@ -7,6 +7,12 @@ extern void shmobile_init_delay(void);
 extern void shmobile_boot_vector(void);
 extern unsigned long shmobile_boot_fn;
 extern unsigned long shmobile_boot_size;
+#ifdef CONFIG_ARCH_RCAR_GEN2
+extern void shmobile_boot_vector_gen2(void);
+extern unsigned long shmobile_boot_fn_gen2;
+extern unsigned long shmobile_boot_cpu_gen2;
+extern unsigned long shmobile_boot_size_gen2;
+#endif /* CONFIG_ARCH_RCAR_GEN2 */
 extern void shmobile_smp_boot(void);
 extern void shmobile_smp_sleep(void);
 extern void shmobile_smp_hook(unsigned int cpu, unsigned long fn,
diff --git a/arch/arm/mach-shmobile/headsmp.S b/arch/arm/mach-shmobile/headsmp.S
index 32e0bf6..cef8e8c 100644
--- a/arch/arm/mach-shmobile/headsmp.S
+++ b/arch/arm/mach-shmobile/headsmp.S
@@ -16,6 +16,11 @@
 #include <asm/assembler.h>
 #include <asm/memory.h>
 
+#define SCTLR_MMU	0x01
+#define BOOTROM_ADDRESS	0xE6340000
+#define RWTCSRA_ADDRESS 0xE6020004
+#define RWTCSRA_WOVF	0x10
+
 /*
  * Reset vector for secondary CPUs.
  * This will be mapped at address 0 by SBAR register.
@@ -37,6 +42,56 @@ shmobile_boot_fn:
 shmobile_boot_size:
 	.long	. - shmobile_boot_vector
 
+#ifdef CONFIG_ARCH_RCAR_GEN2
+/*
+ * Reset vector for R-Car Gen2 and RZ/G1 secondary CPUs.
+ * This will be mapped at address 0 by SBAR register.
+ */
+ENTRY(shmobile_boot_vector_gen2)
+	mrc	p15, 0, r0, c0, c0, 5		@ r0 = MPIDR
+	ldr	r1, shmobile_boot_cpu_gen2
+	cmp	r0, r1
+	bne	shmobile_smp_continue_gen2
+
+	mrc	p15, 0, r1, c1, c0, 0		@ r1 = SCTLR
+	and	r0, r1, #SCTLR_MMU
+	cmp	r0, #SCTLR_MMU
+	beq	shmobile_smp_continue_gen2
+
+	ldr	r0, rwtcsra
+	mov	r1, #0
+	ldrb	r1, [r0]
+	and	r0, r1, #RWTCSRA_WOVF
+	cmp	r0, #RWTCSRA_WOVF
+	bne	shmobile_smp_continue_gen2
+
+	ldr	r0, bootrom
+	bx	r0
+
+shmobile_smp_continue_gen2:
+	ldr     r1, shmobile_boot_fn_gen2
+	bx	r1
+
+ENDPROC(shmobile_boot_vector_gen2)
+
+	.align	4
+rwtcsra:
+	.word	RWTCSRA_ADDRESS
+bootrom:
+	.word	BOOTROM_ADDRESS
+	.globl	shmobile_boot_cpu_gen2
+shmobile_boot_cpu_gen2:
+	.word	0x00000000
+
+	.align	2
+	.globl	shmobile_boot_fn_gen2
+shmobile_boot_fn_gen2:
+	.space	4
+	.globl	shmobile_boot_size_gen2
+shmobile_boot_size_gen2:
+	.long	. - shmobile_boot_vector_gen2
+#endif /* CONFIG_ARCH_RCAR_GEN2 */
+
 /*
  * Per-CPU SMP boot function/argument selection code based on MPIDR
  */
-- 
2.7.4

[PATCH v5 02/26] ARM: dts: r8a7743: Adjust SMP routine size

[Fabrizio Castro]

This patch adjusts the definition of the SMP routine size according
to the latest changes made by commit:
"ARM: shmobile: Add watchdog support"

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
v4->v5:
* no change

 arch/arm/boot/dts/r8a7743.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/r8a7743.dtsi b/arch/arm/boot/dts/r8a7743.dtsi
index 47b62f6..c2943d7 100644
--- a/arch/arm/boot/dts/r8a7743.dtsi
+++ b/arch/arm/boot/dts/r8a7743.dtsi
@@ -973,7 +973,7 @@
 
 			smp-sram@0 {
 				compatible = "renesas,smp-sram";
-				reg = <0 0x10>;
+				reg = <0 0x100>;
 			};
 		};
 
-- 
2.7.4

[PATCH v5 03/26] ARM: dts: r8a7745: Adjust SMP routine size

[Fabrizio Castro]

This patch adjusts the definition of the SMP routine size according
to the latest changes made by commit:
"ARM: shmobile: Add watchdog support"

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
v4->v5:
* no change

 arch/arm/boot/dts/r8a7745.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/r8a7745.dtsi b/arch/arm/boot/dts/r8a7745.dtsi
index ddc3da2..6bc1cf4 100644
--- a/arch/arm/boot/dts/r8a7745.dtsi
+++ b/arch/arm/boot/dts/r8a7745.dtsi
@@ -755,7 +755,7 @@
 
 			smp-sram@0 {
 				compatible = "renesas,smp-sram";
-				reg = <0 0x10>;
+				reg = <0 0x100>;
 			};
 		};
 
-- 
2.7.4

[PATCH v5 04/26] ARM: dts: r8a7790: Adjust SMP routine size

[Fabrizio Castro]

This patch adjusts the definition of the SMP routine size according
to the latest changes made by commit:
"ARM: shmobile: Add watchdog support"

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
v4->v5:
* no change

 arch/arm/boot/dts/r8a7790.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/r8a7790.dtsi b/arch/arm/boot/dts/r8a7790.dtsi
index 3bbcc0b..a84bf35 100644
--- a/arch/arm/boot/dts/r8a7790.dtsi
+++ b/arch/arm/boot/dts/r8a7790.dtsi
@@ -443,7 +443,7 @@
 
 			smp-sram@0 {
 				compatible = "renesas,smp-sram";
-				reg = <0 0x10>;
+				reg = <0 0x100>;
 			};
 		};
 
-- 
2.7.4

[PATCH v5 05/26] ARM: dts: r8a7791: Adjust SMP routine size

[Fabrizio Castro]

This patch adjusts the definition of the SMP routine size according
to the latest changes made by commit:
"ARM: shmobile: Add watchdog support"

Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas-gXvu3+zWzMSzQB+pC5nmwQ@public.gmane.org>
---
v4->v5:
* no change

 arch/arm/boot/dts/r8a7791.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/r8a7791.dtsi b/arch/arm/boot/dts/r8a7791.dtsi
index dc65935..d2a4546 100644
--- a/arch/arm/boot/dts/r8a7791.dtsi
+++ b/arch/arm/boot/dts/r8a7791.dtsi
@@ -407,7 +407,7 @@
 
 			smp-sram@0 {
 				compatible = "renesas,smp-sram";
-				reg = <0 0x10>;
+				reg = <0 0x100>;
 			};
 		};
 
-- 
2.7.4

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[PATCH v5 06/26] ARM: dts: r8a7792: Adjust SMP routine size

[Fabrizio Castro]

This patch adjusts the definition of the SMP routine size according
to the latest changes made by commit:
"ARM: shmobile: Add watchdog support"

Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas-gXvu3+zWzMSzQB+pC5nmwQ@public.gmane.org>
---
v4->v5:
* no change

 arch/arm/boot/dts/r8a7792.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/r8a7792.dtsi b/arch/arm/boot/dts/r8a7792.dtsi
index 268987f..bea0f12 100644
--- a/arch/arm/boot/dts/r8a7792.dtsi
+++ b/arch/arm/boot/dts/r8a7792.dtsi
@@ -341,7 +341,7 @@
 
 			smp-sram@0 {
 				compatible = "renesas,smp-sram";
-				reg = <0 0x10>;
+				reg = <0 0x100>;
 			};
 		};
 
-- 
2.7.4

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[PATCH v5 07/26] ARM: dts: r8a7793: Adjust SMP routine size

[Fabrizio Castro]

This patch adjusts the definition of the SMP routine size according
to the latest changes made by commit:
"ARM: shmobile: Add watchdog support"

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
v4->v5:
* no change

 arch/arm/boot/dts/r8a7793.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/r8a7793.dtsi b/arch/arm/boot/dts/r8a7793.dtsi
index aa7d779..bde6969 100644
--- a/arch/arm/boot/dts/r8a7793.dtsi
+++ b/arch/arm/boot/dts/r8a7793.dtsi
@@ -392,7 +392,7 @@
 
 			smp-sram@0 {
 				compatible = "renesas,smp-sram";
-				reg = <0 0x10>;
+				reg = <0 0x100>;
 			};
 		};
 
-- 
2.7.4

[PATCH v5 08/26] ARM: dts: r8a7794: Adjust SMP routine size

[Fabrizio Castro]

This patch adjusts the definition of the SMP routine size according
to the latest changes made by commit:
"ARM: shmobile: Add watchdog support"

Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas-gXvu3+zWzMSzQB+pC5nmwQ@public.gmane.org>
---
v4->v5:
* no change

 arch/arm/boot/dts/r8a7794.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/r8a7794.dtsi b/arch/arm/boot/dts/r8a7794.dtsi
index d588efa..e47c5f4 100644
--- a/arch/arm/boot/dts/r8a7794.dtsi
+++ b/arch/arm/boot/dts/r8a7794.dtsi
@@ -348,7 +348,7 @@
 
 			smp-sram@0 {
 				compatible = "renesas,smp-sram";
-				reg = <0 0x10>;
+				reg = <0 0x100>;
 			};
 		};
 
-- 
2.7.4

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[PATCH v5 09/26] soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2

[Fabrizio Castro]

This patch allows for platform specific quirks as some of the SoC need
further customization for the watchdog to work properly, like for R-Car
Gen2 and for RZ/G.

Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
---
v4->v5:
* no change

 drivers/soc/renesas/rcar-rst.c | 35 +++++++++++++++++++++++++++++------
 1 file changed, 29 insertions(+), 6 deletions(-)

diff --git a/drivers/soc/renesas/rcar-rst.c b/drivers/soc/renesas/rcar-rst.c
index 3316b02..93febe6 100644
--- a/drivers/soc/renesas/rcar-rst.c
+++ b/drivers/soc/renesas/rcar-rst.c
@@ -13,8 +13,18 @@
 #include <linux/of_address.h>
 #include <linux/soc/renesas/rcar-rst.h>
 
+#define WDTRSTCR_RESET		0xA55A0002
+#define WDTRSTCR		0x0054
+
+static int rcar_rst_enable_wdt_reset(void __iomem *base)
+{
+	iowrite32(WDTRSTCR_RESET, base + WDTRSTCR);
+	return 0;
+}
+
 struct rst_config {
-	unsigned int modemr;	/* Mode Monitoring Register Offset */
+	unsigned int modemr;		/* Mode Monitoring Register Offset */
+	int (*configure)(void *base);	/* Platform specific configuration */
 };
 
 static const struct rst_config rcar_rst_gen1 __initconst = {
@@ -23,6 +33,11 @@ static const struct rst_config rcar_rst_gen1 __initconst = {
 
 static const struct rst_config rcar_rst_gen2 __initconst = {
 	.modemr = 0x60,
+	.configure = rcar_rst_enable_wdt_reset,
+};
+
+static const struct rst_config rcar_rst_gen3 __initconst = {
+	.modemr = 0x60,
 };
 
 static const struct of_device_id rcar_rst_matches[] __initconst = {
@@ -38,11 +53,11 @@ static const struct of_device_id rcar_rst_matches[] __initconst = {
 	{ .compatible = "renesas,r8a7792-rst", .data = &rcar_rst_gen2 },
 	{ .compatible = "renesas,r8a7793-rst", .data = &rcar_rst_gen2 },
 	{ .compatible = "renesas,r8a7794-rst", .data = &rcar_rst_gen2 },
-	/* R-Car Gen3 is handled like R-Car Gen2 */
-	{ .compatible = "renesas,r8a7795-rst", .data = &rcar_rst_gen2 },
-	{ .compatible = "renesas,r8a7796-rst", .data = &rcar_rst_gen2 },
-	{ .compatible = "renesas,r8a77970-rst", .data = &rcar_rst_gen2 },
-	{ .compatible = "renesas,r8a77995-rst", .data = &rcar_rst_gen2 },
+	/* R-Car Gen3 */
+	{ .compatible = "renesas,r8a7795-rst", .data = &rcar_rst_gen3 },
+	{ .compatible = "renesas,r8a7796-rst", .data = &rcar_rst_gen3 },
+	{ .compatible = "renesas,r8a77970-rst", .data = &rcar_rst_gen3 },
+	{ .compatible = "renesas,r8a77995-rst", .data = &rcar_rst_gen3 },
 	{ /* sentinel */ }
 };
 
@@ -71,6 +86,14 @@ static int __init rcar_rst_init(void)
 	rcar_rst_base = base;
 	cfg = match->data;
 	saved_mode = ioread32(base + cfg->modemr);
+	if (cfg->configure) {
+		error = cfg->configure(base);
+		if (error) {
+			pr_warn("%pOF: Cannot run SoC specific configuration\n",
+				np);
+			goto out_put;
+		}
+	}
 
 	pr_debug("%pOF: MODE = 0x%08x\n", np, saved_mode);
 
-- 
2.7.4

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[PATCH v5 10/26] ARM: shmobile: rcar-gen2: Add watchdog support

[Fabrizio Castro]

This patch adds watchdog support by installing shmobile_boot_vector_gen2
to ICRAM1 when enough memory is available, in which case we also keep a
copy of MPIDR to complete the reset vector logic.

Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
---
v4->v5:
* reworked comment style

 arch/arm/mach-shmobile/platsmp-apmu.c |  1 +
 arch/arm/mach-shmobile/pm-rcar-gen2.c | 15 ++++++++++++---
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-shmobile/platsmp-apmu.c b/arch/arm/mach-shmobile/platsmp-apmu.c
index 4422b61..ba732ef 100644
--- a/arch/arm/mach-shmobile/platsmp-apmu.c
+++ b/arch/arm/mach-shmobile/platsmp-apmu.c
@@ -191,6 +191,7 @@ static void __init shmobile_smp_apmu_setup_boot(void)
 {
 	/* install boot code shared by all CPUs */
 	shmobile_boot_fn = __pa_symbol(shmobile_smp_boot);
+	shmobile_boot_fn_gen2 = shmobile_boot_fn;
 }
 
 void __init shmobile_smp_apmu_prepare_cpus(unsigned int max_cpus,
diff --git a/arch/arm/mach-shmobile/pm-rcar-gen2.c b/arch/arm/mach-shmobile/pm-rcar-gen2.c
index e5f215c..5a798b4 100644
--- a/arch/arm/mach-shmobile/pm-rcar-gen2.c
+++ b/arch/arm/mach-shmobile/pm-rcar-gen2.c
@@ -17,6 +17,7 @@
 #include <linux/smp.h>
 #include <linux/soc/renesas/rcar-sysc.h>
 #include <asm/io.h>
+#include <asm/cputype.h>
 #include "common.h"
 #include "rcar-gen2.h"
 
@@ -37,7 +38,6 @@
 #define CA7RESCNT_CODE	0x5a5a0000
 #define CA7RESCNT_CPUS	0xf		/* CPU0-3 */
 
-
 /* On-chip RAM */
 #define ICRAM1		0xe63c0000	/* Inter Connect RAM1 (4 KiB) */
 
@@ -119,8 +119,17 @@ void __init rcar_gen2_pm_init(void)
 	p = ioremap(res.start, resource_size(&res));
 	if (!p)
 		return;
-
-	memcpy_toio(p, shmobile_boot_vector, shmobile_boot_size);
+	/*
+	 * install the reset vector, use the largest version if we have enough
+	 * memory available
+	 */
+	if (resource_size(&res) >= shmobile_boot_size_gen2) {
+		shmobile_boot_cpu_gen2 = read_cpuid_mpidr();
+		memcpy_toio(p, shmobile_boot_vector_gen2,
+			    shmobile_boot_size_gen2);
+	} else {
+		memcpy_toio(p, shmobile_boot_vector, shmobile_boot_size);
+	}
 	iounmap(p);
 
 	/* setup reset vectors */
-- 
2.7.4

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[PATCH v5 11/26] dt-bindings: watchdog: renesas-wdt: Add R-Car Gen2 support

[Fabrizio Castro]

This commit documents the compatibility with R-Car Gen2 and RZ/G
devices by defining the generic compatible string "renesas,rcar-gen2-wdt".
Also, this patch expands the list of SoC-specific compatible strings to
include RZ/G and R-Car Gen2 devices.

Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas-gXvu3+zWzMSzQB+pC5nmwQ@public.gmane.org>
Reviewed-by: Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Reviewed-by: Wolfram Sang <wsa+renesas-jBu1N2QxHDJrcw3mvpCnnVaTQe2KTcn/@public.gmane.org>
---
v4->v5:
* no change

 .../devicetree/bindings/watchdog/renesas-wdt.txt      | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt b/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt
index bf6d1ca..4815128 100644
--- a/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt
+++ b/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt
@@ -1,17 +1,26 @@
 Renesas Watchdog Timer (WDT) Controller
 
 Required properties:
-- compatible : Should be "renesas,<soctype>-wdt", and
-	       "renesas,rcar-gen3-wdt" or "renesas,rza-wdt" as fallback.
+ - compatible : Must be "renesas,<soctype>-wdt", followed by a generic
+		fallback compatible string when compatible with the generic
+		version.
 	       Examples with soctypes are:
+		 - "renesas,r8a7743-wdt" (RZ/G1M)
+		 - "renesas,r8a7745-wdt" (RZ/G1E)
+	         - "renesas,r8a7790-wdt" (R-Car H2)
+	         - "renesas,r8a7791-wdt" (R-Car M2-W)
+	         - "renesas,r8a7792-wdt" (R-Car V2H)
+	         - "renesas,r8a7793-wdt" (R-Car M2-N)
+	         - "renesas,r8a7794-wdt" (R-Car E2)
 	         - "renesas,r8a7795-wdt" (R-Car H3)
 	         - "renesas,r8a7796-wdt" (R-Car M3-W)
 	         - "renesas,r8a77995-wdt" (R-Car D3)
 	         - "renesas,r7s72100-wdt" (RZ/A1)
+		The generic compatible string must be:
+		 - "renesas,rza-wdt" for RZ/A
+		 - "renesas,rcar-gen2-wdt" for R-Car Gen2 and RZ/G
+		 - "renesas,rcar-gen3-wdt" for R-Car Gen3
 
-  When compatible with the generic version, nodes must list the SoC-specific
-  version corresponding to the platform first, followed by the generic
-  version.
 
 - reg : Should contain WDT registers location and length
 - clocks : the clock feeding the watchdog timer.
-- 
2.7.4

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[PATCH v5 12/26] watchdog: renesas_wdt: Add R-Car Gen2 support

[Fabrizio Castro]

Due to commits:
* "ARM: shmobile: Add watchdog support",
* "ARM: shmobile: rcar-gen2: Add watchdog support", and
* "soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2",
we now have everything we needed for the watchdog to work on Gen2 and
RZ/G1.

This commit adds "renesas,rcar-gen2-wdt" as compatible string for R-Car
Gen2 and RZ/G1, and since on those platforms the rwdt clock needs to be
always ON, when suspending to RAM we need to explicitly disable the
counting by clearing TME from RWTCSRA.

Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
---
v4->v5:
* various improvements suggested by Wolfram

 drivers/watchdog/renesas_wdt.c | 27 ++++++++++++++++++++++-----
 1 file changed, 22 insertions(+), 5 deletions(-)

diff --git a/drivers/watchdog/renesas_wdt.c b/drivers/watchdog/renesas_wdt.c
index 831ef83..e972b7b 100644
--- a/drivers/watchdog/renesas_wdt.c
+++ b/drivers/watchdog/renesas_wdt.c
@@ -203,13 +203,29 @@ static int rwdt_remove(struct platform_device *pdev)
 	return 0;
 }
 
-/*
- * This driver does also fit for R-Car Gen2 (r8a779[0-4]) WDT. However, for SMP
- * to work there, one also needs a RESET (RST) driver which does not exist yet
- * due to HW issues. This needs to be solved before adding compatibles here.
- */
+static int __maybe_unused rwdt_suspend(struct device *dev)
+{
+	struct rwdt_priv *priv = dev_get_drvdata(dev);
+
+	if (watchdog_active(&priv->wdev))
+		rwdt_write(priv, priv->cks, RWTCSRA);
+	return 0;
+}
+
+static int __maybe_unused rwdt_resume(struct device *dev)
+{
+	struct rwdt_priv *priv = dev_get_drvdata(dev);
+
+	if (watchdog_active(&priv->wdev))
+		rwdt_write(priv, priv->cks | RWTCSRA_TME, RWTCSRA);
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(rwdt_pm_ops, rwdt_suspend, rwdt_resume);
+
 static const struct of_device_id rwdt_ids[] = {
 	{ .compatible = "renesas,rcar-gen3-wdt", },
+	{ .compatible = "renesas,rcar-gen2-wdt", },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, rwdt_ids);
@@ -218,6 +234,7 @@ static struct platform_driver rwdt_driver = {
 	.driver = {
 		.name = "renesas_wdt",
 		.of_match_table = rwdt_ids,
+		.pm = &rwdt_pm_ops,
 	},
 	.probe = rwdt_probe,
 	.remove = rwdt_remove,
-- 
2.7.4

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[PATCH v5 13/26] watchdog: renesas_wdt: Add restart handler

[Fabrizio Castro]

On iWave's boards iwg20d and iwg22d the only way to reboot the system is
by means of the watchdog.
This patch adds a restart handler to rwdt_ops, and also makes sure we
keep its priority to a medium level, in order to not override other more
effective handlers.

Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Reviewed-by: Guenter Roeck <linux-0h96xk9xTtrk1uMJSBkQmQ@public.gmane.org>
---
v4->v5:
* changed rwdt_restart implementation as per Wolfram comments

 drivers/watchdog/renesas_wdt.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/watchdog/renesas_wdt.c b/drivers/watchdog/renesas_wdt.c
index e972b7b..0f88614 100644
--- a/drivers/watchdog/renesas_wdt.c
+++ b/drivers/watchdog/renesas_wdt.c
@@ -107,6 +107,16 @@ static unsigned int rwdt_get_timeleft(struct watchdog_device *wdev)
 	return DIV_BY_CLKS_PER_SEC(priv, 65536 - val);
 }
 
+static int rwdt_restart(struct watchdog_device *wdev, unsigned long action,
+			void *data)
+{
+	struct rwdt_priv *priv = watchdog_get_drvdata(wdev);
+
+	rwdt_start(wdev);
+	rwdt_write(priv, 0xffff, RWTCNT);
+	return 0;
+}
+
 static const struct watchdog_info rwdt_ident = {
 	.options = WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT,
 	.identity = "Renesas WDT Watchdog",
@@ -118,6 +128,7 @@ static const struct watchdog_ops rwdt_ops = {
 	.stop = rwdt_stop,
 	.ping = rwdt_init_timeout,
 	.get_timeleft = rwdt_get_timeleft,
+	.restart = rwdt_restart,
 };
 
 static int rwdt_probe(struct platform_device *pdev)
@@ -176,6 +187,7 @@ static int rwdt_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, priv);
 	watchdog_set_drvdata(&priv->wdev, priv);
 	watchdog_set_nowayout(&priv->wdev, nowayout);
+	watchdog_set_restart_priority(&priv->wdev, 0);
 
 	/* This overrides the default timeout only if DT configuration was found */
 	ret = watchdog_init_timeout(&priv->wdev, 0, &pdev->dev);
-- 
2.7.4

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[PATCH v5 14/26] ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN

[Fabrizio Castro]

R-Car Gen2 and RZ/G1 platforms come with a watchdog IP, therefore enable
its driver by default.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
v4->v5:
* no change

 arch/arm/configs/shmobile_defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/configs/shmobile_defconfig b/arch/arm/configs/shmobile_defconfig
index 578434c..d5cdad8 100644
--- a/arch/arm/configs/shmobile_defconfig
+++ b/arch/arm/configs/shmobile_defconfig
@@ -132,6 +132,7 @@ CONFIG_CPU_THERMAL=y
 CONFIG_RCAR_THERMAL=y
 CONFIG_WATCHDOG=y
 CONFIG_DA9063_WATCHDOG=y
+CONFIG_RENESAS_WDT=y
 CONFIG_MFD_AS3711=y
 CONFIG_MFD_DA9063=y
 CONFIG_REGULATOR_FIXED_VOLTAGE=y
-- 
2.7.4

[PATCH v5 15/26] clk: renesas: r8a7743: Add rwdt clock

[Fabrizio Castro]

Add "rwdt" clock to r8a7743_mod_clks. Also, since we may need to access
the watchdog registers at any time, declare the clock as critical.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
v4->v5:
* no change

 drivers/clk/renesas/r8a7743-cpg-mssr.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/clk/renesas/r8a7743-cpg-mssr.c b/drivers/clk/renesas/r8a7743-cpg-mssr.c
index 6dc0b30..d3c8b1e 100644
--- a/drivers/clk/renesas/r8a7743-cpg-mssr.c
+++ b/drivers/clk/renesas/r8a7743-cpg-mssr.c
@@ -117,6 +117,7 @@ static const struct mssr_mod_clk r8a7743_mod_clks[] __initconst = {
 	DEF_MOD("cmt1",			 329,	R8A7743_CLK_R),
 	DEF_MOD("usbhs-dmac0",		 330,	R8A7743_CLK_HP),
 	DEF_MOD("usbhs-dmac1",		 331,	R8A7743_CLK_HP),
+	DEF_MOD("rwdt",			 402,	R8A7743_CLK_R),
 	DEF_MOD("irqc",			 407,	R8A7743_CLK_CP),
 	DEF_MOD("intc-sys",		 408,	R8A7743_CLK_ZS),
 	DEF_MOD("audio-dmac1",		 501,	R8A7743_CLK_HP),
@@ -195,6 +196,7 @@ static const struct mssr_mod_clk r8a7743_mod_clks[] __initconst = {
 };
 
 static const unsigned int r8a7743_crit_mod_clks[] __initconst = {
+	MOD_CLK_ID(402),	/* RWDT */
 	MOD_CLK_ID(408),	/* INTC-SYS (GIC) */
 };
 
-- 
2.7.4

[PATCH v5 16/26] clk: renesas: r8a7745: Add rwdt clock

[Fabrizio Castro]

Add "rwdt" clock to r8a7745_mod_clks. Also, since we may need to access
the watchdog registers at any time, declare the clock as critical.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
v4->v5:
* no change

 drivers/clk/renesas/r8a7745-cpg-mssr.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/clk/renesas/r8a7745-cpg-mssr.c b/drivers/clk/renesas/r8a7745-cpg-mssr.c
index 2859504..87f5a36 100644
--- a/drivers/clk/renesas/r8a7745-cpg-mssr.c
+++ b/drivers/clk/renesas/r8a7745-cpg-mssr.c
@@ -114,6 +114,7 @@ static const struct mssr_mod_clk r8a7745_mod_clks[] __initconst = {
 	DEF_MOD("cmt1",			 329,	R8A7745_CLK_R),
 	DEF_MOD("usbhs-dmac0",		 330,	R8A7745_CLK_HP),
 	DEF_MOD("usbhs-dmac1",		 331,	R8A7745_CLK_HP),
+	DEF_MOD("rwdt",			 402,	R8A7745_CLK_R),
 	DEF_MOD("irqc",			 407,	R8A7745_CLK_CP),
 	DEF_MOD("intc-sys",		 408,	R8A7745_CLK_ZS),
 	DEF_MOD("audio-dmac0",		 502,	R8A7745_CLK_HP),
@@ -180,6 +181,7 @@ static const struct mssr_mod_clk r8a7745_mod_clks[] __initconst = {
 };
 
 static const unsigned int r8a7745_crit_mod_clks[] __initconst = {
+	MOD_CLK_ID(402),	/* RWDT */
 	MOD_CLK_ID(408),	/* INTC-SYS (GIC) */
 };
 
-- 
2.7.4

[PATCH v5 17/26] clk: renesas: r8a7790: Add rwdt clock

[Fabrizio Castro]

Add "rwdt" clock to r8a7790_mod_clks. Also, since we may need to access
the watchdog registers at any time, declare the clock as critical.

Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Reviewed-by: Wolfram Sang <wsa+renesas-jBu1N2QxHDJrcw3mvpCnnVaTQe2KTcn/@public.gmane.org>
---
v4->v5:
* no change

 drivers/clk/renesas/r8a7790-cpg-mssr.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/clk/renesas/r8a7790-cpg-mssr.c b/drivers/clk/renesas/r8a7790-cpg-mssr.c
index 46bb55b..f936cb7 100644
--- a/drivers/clk/renesas/r8a7790-cpg-mssr.c
+++ b/drivers/clk/renesas/r8a7790-cpg-mssr.c
@@ -140,6 +140,7 @@ static const struct mssr_mod_clk r8a7790_mod_clks[] __initconst = {
 	DEF_MOD("cmt1",			 329,	R8A7790_CLK_R),
 	DEF_MOD("usbhs-dmac0",		 330,	R8A7790_CLK_HP),
 	DEF_MOD("usbhs-dmac1",		 331,	R8A7790_CLK_HP),
+	DEF_MOD("rwdt",			 402,	R8A7790_CLK_R),
 	DEF_MOD("irqc",			 407,	R8A7790_CLK_CP),
 	DEF_MOD("intc-sys",		 408,	R8A7790_CLK_ZS),
 	DEF_MOD("audio-dmac1",		 501,	R8A7790_CLK_HP),
@@ -211,6 +212,7 @@ static const struct mssr_mod_clk r8a7790_mod_clks[] __initconst = {
 };
 
 static const unsigned int r8a7790_crit_mod_clks[] __initconst = {
+	MOD_CLK_ID(402),	/* RWDT */
 	MOD_CLK_ID(408),	/* INTC-SYS (GIC) */
 };
 
-- 
2.7.4

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[PATCH v5 18/26] clk: renesas: r8a7791/r8a7793: Add rwdt clock

[Fabrizio Castro]

Add "rwdt" clock to r8a7791_mod_clks. Also, since we may need to access
the watchdog registers at any time, declare the clock as critical.

Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Reviewed-by: Wolfram Sang <wsa+renesas-jBu1N2QxHDJrcw3mvpCnnVaTQe2KTcn/@public.gmane.org>
---
v4->v5:
* no change

 drivers/clk/renesas/r8a7791-cpg-mssr.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/clk/renesas/r8a7791-cpg-mssr.c b/drivers/clk/renesas/r8a7791-cpg-mssr.c
index c0b51f9..820b220 100644
--- a/drivers/clk/renesas/r8a7791-cpg-mssr.c
+++ b/drivers/clk/renesas/r8a7791-cpg-mssr.c
@@ -128,6 +128,7 @@ static const struct mssr_mod_clk r8a7791_mod_clks[] __initconst = {
 	DEF_MOD("cmt1",			 329,	R8A7791_CLK_R),
 	DEF_MOD("usbhs-dmac0",		 330,	R8A7791_CLK_HP),
 	DEF_MOD("usbhs-dmac1",		 331,	R8A7791_CLK_HP),
+	DEF_MOD("rwdt",			 402,	R8A7791_CLK_R),
 	DEF_MOD("irqc",			 407,	R8A7791_CLK_CP),
 	DEF_MOD("intc-sys",		 408,	R8A7791_CLK_ZS),
 	DEF_MOD("audio-dmac1",		 501,	R8A7791_CLK_HP),
@@ -209,6 +210,7 @@ static const struct mssr_mod_clk r8a7791_mod_clks[] __initconst = {
 };
 
 static const unsigned int r8a7791_crit_mod_clks[] __initconst = {
+	MOD_CLK_ID(402),	/* RWDT */
 	MOD_CLK_ID(408),	/* INTC-SYS (GIC) */
 };
 
-- 
2.7.4

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[PATCH v5 19/26] clk: renesas: r8a7794: Add rwdt clock

[Fabrizio Castro]

Add "rwdt" clock to r8a7794_mod_clks. Also, since we may need to access
the watchdog registers at any time, declare the clock as critical.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
v4->v5:
* no change

 drivers/clk/renesas/r8a7794-cpg-mssr.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/clk/renesas/r8a7794-cpg-mssr.c b/drivers/clk/renesas/r8a7794-cpg-mssr.c
index ec091a4..2a40bbe 100644
--- a/drivers/clk/renesas/r8a7794-cpg-mssr.c
+++ b/drivers/clk/renesas/r8a7794-cpg-mssr.c
@@ -121,6 +121,7 @@ static const struct mssr_mod_clk r8a7794_mod_clks[] __initconst = {
 	DEF_MOD("cmt1",			 329,	R8A7794_CLK_R),
 	DEF_MOD("usbhs-dmac0",		 330,	R8A7794_CLK_HP),
 	DEF_MOD("usbhs-dmac1",		 331,	R8A7794_CLK_HP),
+	DEF_MOD("rwdt",			 402,	R8A7794_CLK_R),
 	DEF_MOD("irqc",			 407,	R8A7794_CLK_CP),
 	DEF_MOD("intc-sys",		 408,	R8A7794_CLK_ZS),
 	DEF_MOD("audio-dmac0",		 502,	R8A7794_CLK_HP),
@@ -190,6 +191,7 @@ static const struct mssr_mod_clk r8a7794_mod_clks[] __initconst = {
 };
 
 static const unsigned int r8a7794_crit_mod_clks[] __initconst = {
+	MOD_CLK_ID(402),	/* RWDT */
 	MOD_CLK_ID(408),	/* INTC-SYS (GIC) */
 };
 
-- 
2.7.4

[PATCH v5 20/26] ARM: dts: r8a7743: Add watchdog support to SoC dtsi

[Fabrizio Castro]

This patch adds watchdog support to the r8a7743 SoC dtsi.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
v4->v5:
* no change

 arch/arm/boot/dts/r8a7743.dtsi | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/arm/boot/dts/r8a7743.dtsi b/arch/arm/boot/dts/r8a7743.dtsi
index c2943d7..1d4505f 100644
--- a/arch/arm/boot/dts/r8a7743.dtsi
+++ b/arch/arm/boot/dts/r8a7743.dtsi
@@ -368,6 +368,16 @@
 			reg = <0 0xe6160000 0 0x100>;
 		};
 
+		rwdt: watchdog@e6020000 {
+			compatible = "renesas,r8a7743-wdt",
+				     "renesas,rcar-gen2-wdt";
+			reg = <0 0xe6020000 0 0x0c>;
+			clocks = <&cpg CPG_MOD 402>;
+			power-domains = <&sysc R8A7743_PD_ALWAYS_ON>;
+			resets = <&cpg 402>;
+			status = "disabled";
+		};
+
 		sysc: system-controller@e6180000 {
 			compatible = "renesas,r8a7743-sysc";
 			reg = <0 0xe6180000 0 0x200>;
-- 
2.7.4

[PATCH v5 21/26] ARM: dts: r8a7745: Add watchdog support to SoC dtsi

[Fabrizio Castro]

This patch adds watchdog support to the r8a7745 SoC dtsi.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
v4->v5:
* no change

 arch/arm/boot/dts/r8a7745.dtsi | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/arm/boot/dts/r8a7745.dtsi b/arch/arm/boot/dts/r8a7745.dtsi
index 6bc1cf4..5d1b8f2 100644
--- a/arch/arm/boot/dts/r8a7745.dtsi
+++ b/arch/arm/boot/dts/r8a7745.dtsi
@@ -321,6 +321,16 @@
 			reg = <0 0xe6160000 0 0x100>;
 		};
 
+		rwdt: watchdog@e6020000 {
+			compatible = "renesas,r8a7745-wdt",
+				     "renesas,rcar-gen2-wdt";
+			reg = <0 0xe6020000 0 0x0c>;
+			clocks = <&cpg CPG_MOD 402>;
+			power-domains = <&sysc R8A7745_PD_ALWAYS_ON>;
+			resets = <&cpg 402>;
+			status = "disabled";
+		};
+
 		sysc: system-controller@e6180000 {
 			compatible = "renesas,r8a7745-sysc";
 			reg = <0 0xe6180000 0 0x200>;
-- 
2.7.4

[PATCH v5 22/26] ARM: dts: r8a7790: Add watchdog support to SoC dtsi

[Fabrizio Castro]

This commit adds watchdog support to the r8a7790 dtsi.

Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas-gXvu3+zWzMSzQB+pC5nmwQ@public.gmane.org>
Acked-by: Wolfram Sang <wsa+renesas-jBu1N2QxHDJrcw3mvpCnnVaTQe2KTcn/@public.gmane.org>
---
v4->v5:
* no change

 arch/arm/boot/dts/r8a7790.dtsi | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/arm/boot/dts/r8a7790.dtsi b/arch/arm/boot/dts/r8a7790.dtsi
index a84bf35..83d6704 100644
--- a/arch/arm/boot/dts/r8a7790.dtsi
+++ b/arch/arm/boot/dts/r8a7790.dtsi
@@ -218,6 +218,16 @@
 		#size-cells = <2>;
 		ranges;
 
+		rwdt: watchdog@e6020000 {
+			compatible = "renesas,r8a7790-wdt",
+				     "renesas,rcar-gen2-wdt";
+			reg = <0 0xe6020000 0 0x0c>;
+			clocks = <&cpg CPG_MOD 402>;
+			power-domains = <&sysc R8A7790_PD_ALWAYS_ON>;
+			resets = <&cpg 402>;
+			status = "disabled";
+		};
+
 		gpio0: gpio@e6050000 {
 			compatible = "renesas,gpio-r8a7790",
 				     "renesas,rcar-gen2-gpio";
-- 
2.7.4

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[PATCH v5 23/26] ARM: dts: r8a7791: Add watchdog support to SoC dtsi

[Fabrizio Castro]

This commit adds watchdog support to the r8a7791 dtsi.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
v4->v5:
* no change

 arch/arm/boot/dts/r8a7791.dtsi | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/arm/boot/dts/r8a7791.dtsi b/arch/arm/boot/dts/r8a7791.dtsi
index d2a4546..80e20ecd 100644
--- a/arch/arm/boot/dts/r8a7791.dtsi
+++ b/arch/arm/boot/dts/r8a7791.dtsi
@@ -142,6 +142,16 @@
 		#size-cells = <2>;
 		ranges;
 
+		rwdt: watchdog@e6020000 {
+			compatible = "renesas,r8a7791-wdt",
+				     "renesas,rcar-gen2-wdt";
+			reg = <0 0xe6020000 0 0x0c>;
+			clocks = <&cpg CPG_MOD 402>;
+			power-domains = <&sysc R8A7791_PD_ALWAYS_ON>;
+			resets = <&cpg 402>;
+			status = "disabled";
+		};
+
 		gpio0: gpio@e6050000 {
 			compatible = "renesas,gpio-r8a7791",
 				     "renesas,rcar-gen2-gpio";
-- 
2.7.4

[PATCH v5 24/26] ARM: dts: r8a7794: Add watchdog support to SoC dtsi

[Fabrizio Castro]

This commit adds watchdog support to the r8a7794 dtsi.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
v4->v5:
* no change

 arch/arm/boot/dts/r8a7794.dtsi | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/arm/boot/dts/r8a7794.dtsi b/arch/arm/boot/dts/r8a7794.dtsi
index e47c5f4..1c9b149 100644
--- a/arch/arm/boot/dts/r8a7794.dtsi
+++ b/arch/arm/boot/dts/r8a7794.dtsi
@@ -119,6 +119,16 @@
 		#size-cells = <2>;
 		ranges;
 
+		rwdt: watchdog@e6020000 {
+			compatible = "renesas,r8a7794-wdt",
+				     "renesas,rcar-gen2-wdt";
+			reg = <0 0xe6020000 0 0x0c>;
+			clocks = <&cpg CPG_MOD 402>;
+			power-domains = <&sysc R8A7794_PD_ALWAYS_ON>;
+			resets = <&cpg 402>;
+			status = "disabled";
+		};
+
 		gpio0: gpio@e6050000 {
 			compatible = "renesas,gpio-r8a7794",
 				     "renesas,rcar-gen2-gpio";
-- 
2.7.4

[PATCH v5 25/26] ARM: dts: iwg20m: Add watchdog support to SoM dtsi

[Fabrizio Castro]

This patch enables the watchdog from within the iwg20m SoM dtsi.

Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas-gXvu3+zWzMSzQB+pC5nmwQ@public.gmane.org>
Reviewed-by: Wolfram Sang <wsa+renesas-jBu1N2QxHDJrcw3mvpCnnVaTQe2KTcn/@public.gmane.org>
---
v4->v5:
* no change

 arch/arm/boot/dts/r8a7743-iwg20m.dtsi | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/boot/dts/r8a7743-iwg20m.dtsi b/arch/arm/boot/dts/r8a7743-iwg20m.dtsi
index 1d3e950..d364685 100644
--- a/arch/arm/boot/dts/r8a7743-iwg20m.dtsi
+++ b/arch/arm/boot/dts/r8a7743-iwg20m.dtsi
@@ -91,6 +91,11 @@
 	};
 };
 
+&rwdt {
+	timeout-sec = <60>;
+	status = "okay";
+};
+
 &sdhi0 {
 	pinctrl-0 = <&sdhi0_pins>;
 	pinctrl-names = "default";
-- 
2.7.4

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[PATCH v5 26/26] ARM: dts: iwg22m: Add watchdog support to SoM dtsi

[Fabrizio Castro]

This patch enables the watchdog from within the iwg20m SoM dtsi.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
v4->v5:
* no change

 arch/arm/boot/dts/r8a7745-iwg22m.dtsi | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/boot/dts/r8a7745-iwg22m.dtsi b/arch/arm/boot/dts/r8a7745-iwg22m.dtsi
index 8d0a392b..29b6e10 100644
--- a/arch/arm/boot/dts/r8a7745-iwg22m.dtsi
+++ b/arch/arm/boot/dts/r8a7745-iwg22m.dtsi
@@ -91,6 +91,11 @@
 	};
 };
 
+&rwdt {
+	timeout-sec = <60>;
+	status = "okay";
+};
+
 &sdhi1 {
 	pinctrl-0 = <&sdhi1_pins>;
 	pinctrl-names = "default";
-- 
2.7.4

Re: [PATCH v5 12/26] watchdog: renesas_wdt: Add R-Car Gen2 support

[Guenter Roeck]

On Mon, Feb 12, 2018 at 05:44:21PM +0000, Fabrizio Castro wrote:
> Due to commits:
> * "ARM: shmobile: Add watchdog support",
> * "ARM: shmobile: rcar-gen2: Add watchdog support", and
> * "soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2",
> we now have everything we needed for the watchdog to work on Gen2 and
> RZ/G1.
> 
> This commit adds "renesas,rcar-gen2-wdt" as compatible string for R-Car
> Gen2 and RZ/G1, and since on those platforms the rwdt clock needs to be
> always ON, when suspending to RAM we need to explicitly disable the
> counting by clearing TME from RWTCSRA.
> 
> Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
> Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>

Reviewed-by: Guenter Roeck <linux-0h96xk9xTtrk1uMJSBkQmQ@public.gmane.org>

> ---
> v4->v5:
> * various improvements suggested by Wolfram
> 
>  drivers/watchdog/renesas_wdt.c | 27 ++++++++++++++++++++++-----
>  1 file changed, 22 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/watchdog/renesas_wdt.c b/drivers/watchdog/renesas_wdt.c
> index 831ef83..e972b7b 100644
> --- a/drivers/watchdog/renesas_wdt.c
> +++ b/drivers/watchdog/renesas_wdt.c
> @@ -203,13 +203,29 @@ static int rwdt_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> -/*
> - * This driver does also fit for R-Car Gen2 (r8a779[0-4]) WDT. However, for SMP
> - * to work there, one also needs a RESET (RST) driver which does not exist yet
> - * due to HW issues. This needs to be solved before adding compatibles here.
> - */
> +static int __maybe_unused rwdt_suspend(struct device *dev)
> +{
> +	struct rwdt_priv *priv = dev_get_drvdata(dev);
> +
> +	if (watchdog_active(&priv->wdev))
> +		rwdt_write(priv, priv->cks, RWTCSRA);
> +	return 0;
> +}
> +
> +static int __maybe_unused rwdt_resume(struct device *dev)
> +{
> +	struct rwdt_priv *priv = dev_get_drvdata(dev);
> +
> +	if (watchdog_active(&priv->wdev))
> +		rwdt_write(priv, priv->cks | RWTCSRA_TME, RWTCSRA);
> +	return 0;
> +}
> +
> +static SIMPLE_DEV_PM_OPS(rwdt_pm_ops, rwdt_suspend, rwdt_resume);
> +
>  static const struct of_device_id rwdt_ids[] = {
>  	{ .compatible = "renesas,rcar-gen3-wdt", },
> +	{ .compatible = "renesas,rcar-gen2-wdt", },
>  	{ /* sentinel */ }
>  };
>  MODULE_DEVICE_TABLE(of, rwdt_ids);
> @@ -218,6 +234,7 @@ static struct platform_driver rwdt_driver = {
>  	.driver = {
>  		.name = "renesas_wdt",
>  		.of_match_table = rwdt_ids,
> +		.pm = &rwdt_pm_ops,
>  	},
>  	.probe = rwdt_probe,
>  	.remove = rwdt_remove,
> -- 
> 2.7.4
> 
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Re: [PATCH v5 12/26] watchdog: renesas_wdt: Add R-Car Gen2 support

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 985 bytes --]

On Mon, Feb 12, 2018 at 05:44:21PM +0000, Fabrizio Castro wrote:
> Due to commits:
> * "ARM: shmobile: Add watchdog support",
> * "ARM: shmobile: rcar-gen2: Add watchdog support", and
> * "soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2",
> we now have everything we needed for the watchdog to work on Gen2 and
> RZ/G1.
> 
> This commit adds "renesas,rcar-gen2-wdt" as compatible string for R-Car
> Gen2 and RZ/G1, and since on those platforms the rwdt clock needs to be
> always ON, when suspending to RAM we need to explicitly disable the
> counting by clearing TME from RWTCSRA.
> 
> Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
> Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRj3fQ9qLvQP4Q@public.gmane.orgs.com>
> ---
> v4->v5:
> * various improvements suggested by Wolfram
> 

Reviewed-by: Wolfram Sang <wsa+renesas-jBu1N2QxHDJrcw3mvpCnnVaTQe2KTcn/@public.gmane.org>


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Re: [PATCH v5 13/26] watchdog: renesas_wdt: Add restart handler

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 614 bytes --]

On Mon, Feb 12, 2018 at 05:44:22PM +0000, Fabrizio Castro wrote:
> On iWave's boards iwg20d and iwg22d the only way to reboot the system is
> by means of the watchdog.
> This patch adds a restart handler to rwdt_ops, and also makes sure we
> keep its priority to a medium level, in order to not override other more
> effective handlers.
> 
> Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
> Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
> Reviewed-by: Guenter Roeck <linux@roeck-us.net>

Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>


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Re: [PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1

[Simon Horman]

On Mon, Feb 12, 2018 at 05:44:09PM +0000, Fabrizio Castro wrote:
> Dear All,
> 
> this series has been around for some time as RFC, and it has collected
> useful comments from the community along the way.
> The solution proposed by this patch set works for most R-Car Gen2 and
> RZ/G1 devices, but not all of them. We now know that for some R-Car
> Gen2 early revisions there is no proper software fix. Anyway, no
> product has been built around early revisions, but development boards
> mounting early revisions (basically prototypes) are still out there.
> As a result, this series isn't enabling the internal watchdog on R-Car
> Gen2 boards, developers may enable it in board specific device trees
> if needed.
> This series has been tested by me on the iwg20d, iwg22d, Lager, Alt,
> and Koelsch boards.
> 
> The problem
> ===========
> To deal with SMP on R-Car Gen2 and RZ/G1, we install a reset vector
> to ICRAM1 and we program the [S]BAR registers so that when we turn ON
> the non-boot CPUs they are redirected to the reset vector installed by
> Linux in ICRAM1, and eventually they continue the execution to RAM,
> where the SMP bring-up code will take care of the rest.
> The content of the [S]BAR registers survives a watchdog triggered reset,
> and as such after the watchdog fires the boot core will try and execute
> the SMP bring-up code instead of jumping to the bootrom code.
> 
> The fix
> =======
> The main strategy for the solution is to let the reset vector decide
> if it needs to jump to shmobile_boot_fn or to the bootrom code.
> In a watchdog triggered reset scenario, since the [S]BAR registers keep
> their values, the boot CPU will jump into the newly designed reset
> vector, the assembly routine will eventually test WOVF (a bit in register
> RWTCSRA that indicates if the watchdog counter has overflown, the value
> of this bit gets retained in this scenario), and jump to the bootrom code
> which will in turn load up the bootloader, etc.
> When bringing up SMP or using CPU hotplug, the reset vector will jump
> to shmobile_boot_fn instead.
> 
> Thank you All for your help.
> 
> Best regards,
> 
> Fabrizio Castro (26):
>   ARM: shmobile: Add watchdog support
>   ARM: dts: r8a7743: Adjust SMP routine size
>   ARM: dts: r8a7745: Adjust SMP routine size
>   ARM: dts: r8a7790: Adjust SMP routine size
>   ARM: dts: r8a7791: Adjust SMP routine size
>   ARM: dts: r8a7792: Adjust SMP routine size
>   ARM: dts: r8a7793: Adjust SMP routine size
>   ARM: dts: r8a7794: Adjust SMP routine size
>   soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2
>   ARM: shmobile: rcar-gen2: Add watchdog support
>   dt-bindings: watchdog: renesas-wdt: Add R-Car Gen2 support
>   watchdog: renesas_wdt: Add R-Car Gen2 support
>   watchdog: renesas_wdt: Add restart handler
>   ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN
>   clk: renesas: r8a7743: Add rwdt clock
>   clk: renesas: r8a7745: Add rwdt clock
>   clk: renesas: r8a7790: Add rwdt clock
>   clk: renesas: r8a7791/r8a7793: Add rwdt clock
>   clk: renesas: r8a7794: Add rwdt clock
>   ARM: dts: r8a7743: Add watchdog support to SoC dtsi
>   ARM: dts: r8a7745: Add watchdog support to SoC dtsi
>   ARM: dts: r8a7790: Add watchdog support to SoC dtsi
>   ARM: dts: r8a7791: Add watchdog support to SoC dtsi
>   ARM: dts: r8a7794: Add watchdog support to SoC dtsi
>   ARM: dts: iwg20m: Add watchdog support to SoM dtsi
>   ARM: dts: iwg22m: Add watchdog support to SoM dtsi

Thanks, I have applied the above "dts" and "defconfig" patches for v4.17.

Re: [PATCH v5 09/26] soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2

[Simon Horman]

On Mon, Feb 12, 2018 at 05:44:18PM +0000, Fabrizio Castro wrote:
> This patch allows for platform specific quirks as some of the SoC need
> further customization for the watchdog to work properly, like for R-Car
> Gen2 and for RZ/G.
> 
> Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
> Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>

I am fine with this patch but please rebase it on top of
renesas-devel-20180212-v4.16-rc1 (or later).

Re: [PATCH v5 10/26] ARM: shmobile: rcar-gen2: Add watchdog support

[Simon Horman]

On Mon, Feb 12, 2018 at 05:44:19PM +0000, Fabrizio Castro wrote:
> This patch adds watchdog support by installing shmobile_boot_vector_gen2
> to ICRAM1 when enough memory is available, in which case we also keep a
> copy of MPIDR to complete the reset vector logic.
> 
> Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
> Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>

I am marking this patch as deferred as it has dependencies on watchdog driver
and in turn clock changes in this series.
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RE: [PATCH v5 09/26] soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2

[Fabrizio Castro]

Hello Simon,

> Subject: Re: [PATCH v5 09/26] soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2
>
> On Mon, Feb 12, 2018 at 05:44:18PM +0000, Fabrizio Castro wrote:
> > This patch allows for platform specific quirks as some of the SoC need
> > further customization for the watchdog to work properly, like for R-Car
> > Gen2 and for RZ/G.
> >
> > Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
> > Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
>
> I am fine with this patch but please rebase it on top of
> renesas-devel-20180212-v4.16-rc1 (or later).

sure, I will.

Thanks,
Fab



Renesas Electronics Europe Ltd, Dukes Meadow, Millboard Road, Bourne End, Buckinghamshire, SL8 5FH, UK. Registered in England & Wales under Registered No. 04586709.

[PATCH v6 09/26] soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2

[Fabrizio Castro]

This patch allows for platform specific quirks as some of the SoC need
further customization for the watchdog to work properly, like for R-Car
Gen2 and for RZ/G.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
---
v5->v6:
* rebased on top of renesas-devel-20180213-v4.16-rc1

 drivers/soc/renesas/rcar-rst.c | 37 ++++++++++++++++++++++++++++++-------
 1 file changed, 30 insertions(+), 7 deletions(-)

diff --git a/drivers/soc/renesas/rcar-rst.c b/drivers/soc/renesas/rcar-rst.c
index e2340eb..3413666 100644
--- a/drivers/soc/renesas/rcar-rst.c
+++ b/drivers/soc/renesas/rcar-rst.c
@@ -13,8 +13,18 @@
 #include <linux/of_address.h>
 #include <linux/soc/renesas/rcar-rst.h>
 
+#define WDTRSTCR_RESET		0xA55A0002
+#define WDTRSTCR		0x0054
+
+static int rcar_rst_enable_wdt_reset(void __iomem *base)
+{
+	iowrite32(WDTRSTCR_RESET, base + WDTRSTCR);
+	return 0;
+}
+
 struct rst_config {
-	unsigned int modemr;	/* Mode Monitoring Register Offset */
+	unsigned int modemr;		/* Mode Monitoring Register Offset */
+	int (*configure)(void *base);	/* Platform specific configuration */
 };
 
 static const struct rst_config rcar_rst_gen1 __initconst = {
@@ -23,6 +33,11 @@ static const struct rst_config rcar_rst_gen1 __initconst = {
 
 static const struct rst_config rcar_rst_gen2 __initconst = {
 	.modemr = 0x60,
+	.configure = rcar_rst_enable_wdt_reset,
+};
+
+static const struct rst_config rcar_rst_gen3 __initconst = {
+	.modemr = 0x60,
 };
 
 static const struct of_device_id rcar_rst_matches[] __initconst = {
@@ -38,12 +53,12 @@ static const struct of_device_id rcar_rst_matches[] __initconst = {
 	{ .compatible = "renesas,r8a7792-rst", .data = &rcar_rst_gen2 },
 	{ .compatible = "renesas,r8a7793-rst", .data = &rcar_rst_gen2 },
 	{ .compatible = "renesas,r8a7794-rst", .data = &rcar_rst_gen2 },
-	/* R-Car Gen3 is handled like R-Car Gen2 */
-	{ .compatible = "renesas,r8a7795-rst", .data = &rcar_rst_gen2 },
-	{ .compatible = "renesas,r8a7796-rst", .data = &rcar_rst_gen2 },
-	{ .compatible = "renesas,r8a77970-rst", .data = &rcar_rst_gen2 },
-	{ .compatible = "renesas,r8a77980-rst", .data = &rcar_rst_gen2 },
-	{ .compatible = "renesas,r8a77995-rst", .data = &rcar_rst_gen2 },
+	/* R-Car Gen3 */
+	{ .compatible = "renesas,r8a7795-rst", .data = &rcar_rst_gen3 },
+	{ .compatible = "renesas,r8a7796-rst", .data = &rcar_rst_gen3 },
+	{ .compatible = "renesas,r8a77970-rst", .data = &rcar_rst_gen3 },
+	{ .compatible = "renesas,r8a77980-rst", .data = &rcar_rst_gen3 },
+	{ .compatible = "renesas,r8a77995-rst", .data = &rcar_rst_gen3 },
 	{ /* sentinel */ }
 };
 
@@ -72,6 +87,14 @@ static int __init rcar_rst_init(void)
 	rcar_rst_base = base;
 	cfg = match->data;
 	saved_mode = ioread32(base + cfg->modemr);
+	if (cfg->configure) {
+		error = cfg->configure(base);
+		if (error) {
+			pr_warn("%pOF: Cannot run SoC specific configuration\n",
+				np);
+			goto out_put;
+		}
+	}
 
 	pr_debug("%pOF: MODE = 0x%08x\n", np, saved_mode);
 
-- 
2.7.4

RE: [PATCH v5 14/26] ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN

[Fabrizio Castro]

Hello Simon,

what do you think about enabling the watchdog in multi_v7_defconfig as a module?

Thanks,
Fab

> Subject: [PATCH v5 14/26] ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN
>
> R-Car Gen2 and RZ/G1 platforms come with a watchdog IP, therefore enable
> its driver by default.
>
> Signed-off-by: Fabrizio Castro <fabrizio.castro-kTT6dE0pTRh9uiUsa/gSgQ@public.gmane.org>
> Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram-kTT6dE0pTRj3fQ9qLvQP4Q@public.gmane.orgs.com>
> Reviewed-by: Wolfram Sang <wsa+renesas-jBu1N2QxHDJrcw3mvpCnnVaTQe2KTcn/@public.gmane.org>
> ---
> v4->v5:
> * no change
>
>  arch/arm/configs/shmobile_defconfig | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm/configs/shmobile_defconfig b/arch/arm/configs/shmobile_defconfig
> index 578434c..d5cdad8 100644
> --- a/arch/arm/configs/shmobile_defconfig
> +++ b/arch/arm/configs/shmobile_defconfig
> @@ -132,6 +132,7 @@ CONFIG_CPU_THERMAL=y
>  CONFIG_RCAR_THERMAL=y
>  CONFIG_WATCHDOG=y
>  CONFIG_DA9063_WATCHDOG=y
> +CONFIG_RENESAS_WDT=y
>  CONFIG_MFD_AS3711=y
>  CONFIG_MFD_DA9063=y
>  CONFIG_REGULATOR_FIXED_VOLTAGE=y
> --
> 2.7.4




Renesas Electronics Europe Ltd, Dukes Meadow, Millboard Road, Bourne End, Buckinghamshire, SL8 5FH, UK. Registered in England & Wales under Registered No. 04586709.
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Re: [PATCH v6 09/26] soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2

[Simon Horman]

On Tue, Feb 13, 2018 at 01:02:44PM +0000, Fabrizio Castro wrote:
> This patch allows for platform specific quirks as some of the SoC need
> further customization for the watchdog to work properly, like for R-Car
> Gen2 and for RZ/G.
> 
> Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
> Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
> ---
> v5->v6:
> * rebased on top of renesas-devel-20180213-v4.16-rc1

Thanks, applied.

Re: [PATCH v5 14/26] ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN

[Simon Horman]

On Tue, Feb 13, 2018 at 01:08:19PM +0000, Fabrizio Castro wrote:
> Hello Simon,
> 
> what do you think about enabling the watchdog in multi_v7_defconfig as a module?

I think its a good idea.
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Re: [PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1

[Geert Uytterhoeven]

On Mon, Feb 12, 2018 at 6:44 PM, Fabrizio Castro
<fabrizio.castro@bp.renesas.com> wrote:
> this series has been around for some time as RFC, and it has collected
> useful comments from the community along the way.
> The solution proposed by this patch set works for most R-Car Gen2 and
> RZ/G1 devices, but not all of them. We now know that for some R-Car
> Gen2 early revisions there is no proper software fix. Anyway, no
> product has been built around early revisions, but development boards
> mounting early revisions (basically prototypes) are still out there.
> As a result, this series isn't enabling the internal watchdog on R-Car
> Gen2 boards, developers may enable it in board specific device trees
> if needed.
> This series has been tested by me on the iwg20d, iwg22d, Lager, Alt,
> and Koelsch boards.
>
> The problem
> ===========
> To deal with SMP on R-Car Gen2 and RZ/G1, we install a reset vector
> to ICRAM1 and we program the [S]BAR registers so that when we turn ON
> the non-boot CPUs they are redirected to the reset vector installed by
> Linux in ICRAM1, and eventually they continue the execution to RAM,
> where the SMP bring-up code will take care of the rest.
> The content of the [S]BAR registers survives a watchdog triggered reset,
> and as such after the watchdog fires the boot core will try and execute
> the SMP bring-up code instead of jumping to the bootrom code.
>
> The fix
> =======
> The main strategy for the solution is to let the reset vector decide
> if it needs to jump to shmobile_boot_fn or to the bootrom code.
> In a watchdog triggered reset scenario, since the [S]BAR registers keep
> their values, the boot CPU will jump into the newly designed reset
> vector, the assembly routine will eventually test WOVF (a bit in register
> RWTCSRA that indicates if the watchdog counter has overflown, the value
> of this bit gets retained in this scenario), and jump to the bootrom code
> which will in turn load up the bootloader, etc.
> When bringing up SMP or using CPU hotplug, the reset vector will jump
> to shmobile_boot_fn instead.
>
> Thank you All for your help.
>
> Best regards,
>
> Fabrizio Castro (26):
>   ARM: shmobile: Add watchdog support
>   ARM: dts: r8a7743: Adjust SMP routine size
>   ARM: dts: r8a7745: Adjust SMP routine size
>   ARM: dts: r8a7790: Adjust SMP routine size
>   ARM: dts: r8a7791: Adjust SMP routine size
>   ARM: dts: r8a7792: Adjust SMP routine size
>   ARM: dts: r8a7793: Adjust SMP routine size
>   ARM: dts: r8a7794: Adjust SMP routine size
>   soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2
>   ARM: shmobile: rcar-gen2: Add watchdog support
>   dt-bindings: watchdog: renesas-wdt: Add R-Car Gen2 support
>   watchdog: renesas_wdt: Add R-Car Gen2 support
>   watchdog: renesas_wdt: Add restart handler
>   ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN
>   clk: renesas: r8a7743: Add rwdt clock
>   clk: renesas: r8a7745: Add rwdt clock
>   clk: renesas: r8a7790: Add rwdt clock
>   clk: renesas: r8a7791/r8a7793: Add rwdt clock
>   clk: renesas: r8a7794: Add rwdt clock
>   ARM: dts: r8a7743: Add watchdog support to SoC dtsi
>   ARM: dts: r8a7745: Add watchdog support to SoC dtsi
>   ARM: dts: r8a7790: Add watchdog support to SoC dtsi
>   ARM: dts: r8a7791: Add watchdog support to SoC dtsi
>   ARM: dts: r8a7794: Add watchdog support to SoC dtsi
>   ARM: dts: iwg20m: Add watchdog support to SoM dtsi
>   ARM: dts: iwg22m: Add watchdog support to SoM dtsi
>
>  .../devicetree/bindings/watchdog/renesas-wdt.txt   | 19 ++++++--
>  arch/arm/boot/dts/r8a7743-iwg20m.dtsi              |  5 ++
>  arch/arm/boot/dts/r8a7743.dtsi                     | 12 ++++-
>  arch/arm/boot/dts/r8a7745-iwg22m.dtsi              |  5 ++
>  arch/arm/boot/dts/r8a7745.dtsi                     | 12 ++++-
>  arch/arm/boot/dts/r8a7790.dtsi                     | 12 ++++-
>  arch/arm/boot/dts/r8a7791.dtsi                     | 12 ++++-
>  arch/arm/boot/dts/r8a7792.dtsi                     |  2 +-
>  arch/arm/boot/dts/r8a7793.dtsi                     |  2 +-
>  arch/arm/boot/dts/r8a7794.dtsi                     | 12 ++++-
>  arch/arm/configs/shmobile_defconfig                |  1 +
>  arch/arm/mach-shmobile/common.h                    |  6 +++
>  arch/arm/mach-shmobile/headsmp.S                   | 55 ++++++++++++++++++++++
>  arch/arm/mach-shmobile/platsmp-apmu.c              |  1 +
>  arch/arm/mach-shmobile/pm-rcar-gen2.c              | 15 ++++--
>  drivers/clk/renesas/r8a7743-cpg-mssr.c             |  2 +
>  drivers/clk/renesas/r8a7745-cpg-mssr.c             |  2 +
>  drivers/clk/renesas/r8a7790-cpg-mssr.c             |  2 +
>  drivers/clk/renesas/r8a7791-cpg-mssr.c             |  2 +
>  drivers/clk/renesas/r8a7794-cpg-mssr.c             |  2 +
>  drivers/soc/renesas/rcar-rst.c                     | 35 +++++++++++---
>  drivers/watchdog/renesas_wdt.c                     | 39 +++++++++++++--

Thanks, I've queued the clock patches in clk-renesas-for-v4.17, as they are
a hard dependency for:
  (1) The new reset vector in arch/arm/mach-shmobile/
  (2) The watchdog driver.

Note that the watchdog driver itself (2) has a hard dependency on the
new reset vector (1).

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1

[Simon Horman]

On Tue, Feb 20, 2018 at 01:51:28PM +0100, Geert Uytterhoeven wrote:
> On Mon, Feb 12, 2018 at 6:44 PM, Fabrizio Castro
> <fabrizio.castro@bp.renesas.com> wrote:
> > this series has been around for some time as RFC, and it has collected
> > useful comments from the community along the way.
> > The solution proposed by this patch set works for most R-Car Gen2 and
> > RZ/G1 devices, but not all of them. We now know that for some R-Car
> > Gen2 early revisions there is no proper software fix. Anyway, no
> > product has been built around early revisions, but development boards
> > mounting early revisions (basically prototypes) are still out there.
> > As a result, this series isn't enabling the internal watchdog on R-Car
> > Gen2 boards, developers may enable it in board specific device trees
> > if needed.
> > This series has been tested by me on the iwg20d, iwg22d, Lager, Alt,
> > and Koelsch boards.
> >
> > The problem
> > ===========
> > To deal with SMP on R-Car Gen2 and RZ/G1, we install a reset vector
> > to ICRAM1 and we program the [S]BAR registers so that when we turn ON
> > the non-boot CPUs they are redirected to the reset vector installed by
> > Linux in ICRAM1, and eventually they continue the execution to RAM,
> > where the SMP bring-up code will take care of the rest.
> > The content of the [S]BAR registers survives a watchdog triggered reset,
> > and as such after the watchdog fires the boot core will try and execute
> > the SMP bring-up code instead of jumping to the bootrom code.
> >
> > The fix
> > =======
> > The main strategy for the solution is to let the reset vector decide
> > if it needs to jump to shmobile_boot_fn or to the bootrom code.
> > In a watchdog triggered reset scenario, since the [S]BAR registers keep
> > their values, the boot CPU will jump into the newly designed reset
> > vector, the assembly routine will eventually test WOVF (a bit in register
> > RWTCSRA that indicates if the watchdog counter has overflown, the value
> > of this bit gets retained in this scenario), and jump to the bootrom code
> > which will in turn load up the bootloader, etc.
> > When bringing up SMP or using CPU hotplug, the reset vector will jump
> > to shmobile_boot_fn instead.
> >
> > Thank you All for your help.
> >
> > Best regards,
> >
> > Fabrizio Castro (26):
> >   ARM: shmobile: Add watchdog support
> >   ARM: dts: r8a7743: Adjust SMP routine size
> >   ARM: dts: r8a7745: Adjust SMP routine size
> >   ARM: dts: r8a7790: Adjust SMP routine size
> >   ARM: dts: r8a7791: Adjust SMP routine size
> >   ARM: dts: r8a7792: Adjust SMP routine size
> >   ARM: dts: r8a7793: Adjust SMP routine size
> >   ARM: dts: r8a7794: Adjust SMP routine size
> >   soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2
> >   ARM: shmobile: rcar-gen2: Add watchdog support
> >   dt-bindings: watchdog: renesas-wdt: Add R-Car Gen2 support
> >   watchdog: renesas_wdt: Add R-Car Gen2 support
> >   watchdog: renesas_wdt: Add restart handler
> >   ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN
> >   clk: renesas: r8a7743: Add rwdt clock
> >   clk: renesas: r8a7745: Add rwdt clock
> >   clk: renesas: r8a7790: Add rwdt clock
> >   clk: renesas: r8a7791/r8a7793: Add rwdt clock
> >   clk: renesas: r8a7794: Add rwdt clock
> >   ARM: dts: r8a7743: Add watchdog support to SoC dtsi
> >   ARM: dts: r8a7745: Add watchdog support to SoC dtsi
> >   ARM: dts: r8a7790: Add watchdog support to SoC dtsi
> >   ARM: dts: r8a7791: Add watchdog support to SoC dtsi
> >   ARM: dts: r8a7794: Add watchdog support to SoC dtsi
> >   ARM: dts: iwg20m: Add watchdog support to SoM dtsi
> >   ARM: dts: iwg22m: Add watchdog support to SoM dtsi
> >
> >  .../devicetree/bindings/watchdog/renesas-wdt.txt   | 19 ++++++--
> >  arch/arm/boot/dts/r8a7743-iwg20m.dtsi              |  5 ++
> >  arch/arm/boot/dts/r8a7743.dtsi                     | 12 ++++-
> >  arch/arm/boot/dts/r8a7745-iwg22m.dtsi              |  5 ++
> >  arch/arm/boot/dts/r8a7745.dtsi                     | 12 ++++-
> >  arch/arm/boot/dts/r8a7790.dtsi                     | 12 ++++-
> >  arch/arm/boot/dts/r8a7791.dtsi                     | 12 ++++-
> >  arch/arm/boot/dts/r8a7792.dtsi                     |  2 +-
> >  arch/arm/boot/dts/r8a7793.dtsi                     |  2 +-
> >  arch/arm/boot/dts/r8a7794.dtsi                     | 12 ++++-
> >  arch/arm/configs/shmobile_defconfig                |  1 +
> >  arch/arm/mach-shmobile/common.h                    |  6 +++
> >  arch/arm/mach-shmobile/headsmp.S                   | 55 ++++++++++++++++++++++
> >  arch/arm/mach-shmobile/platsmp-apmu.c              |  1 +
> >  arch/arm/mach-shmobile/pm-rcar-gen2.c              | 15 ++++--
> >  drivers/clk/renesas/r8a7743-cpg-mssr.c             |  2 +
> >  drivers/clk/renesas/r8a7745-cpg-mssr.c             |  2 +
> >  drivers/clk/renesas/r8a7790-cpg-mssr.c             |  2 +
> >  drivers/clk/renesas/r8a7791-cpg-mssr.c             |  2 +
> >  drivers/clk/renesas/r8a7794-cpg-mssr.c             |  2 +
> >  drivers/soc/renesas/rcar-rst.c                     | 35 +++++++++++---
> >  drivers/watchdog/renesas_wdt.c                     | 39 +++++++++++++--
> 
> Thanks, I've queued the clock patches in clk-renesas-for-v4.17, as they are
> a hard dependency for:
>   (1) The new reset vector in arch/arm/mach-shmobile/
>   (2) The watchdog driver.
> 
> Note that the watchdog driver itself (2) has a hard dependency on the
> new reset vector (1).

Thanks, I have marked the watchdog driver patch as Deferred.
Please resubmit or otherwise ping me once they dependencies
are in an rc release.

Re: [PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1

[Geert Uytterhoeven]

Hi Simon,

On Wed, Feb 21, 2018 at 5:13 PM, Simon Horman <horms@verge.net.au> wrote:
> On Tue, Feb 20, 2018 at 01:51:28PM +0100, Geert Uytterhoeven wrote:
>> On Mon, Feb 12, 2018 at 6:44 PM, Fabrizio Castro
>> <fabrizio.castro@bp.renesas.com> wrote:
>> > this series has been around for some time as RFC, and it has collected
>> > useful comments from the community along the way.
>> > The solution proposed by this patch set works for most R-Car Gen2 and
>> > RZ/G1 devices, but not all of them. We now know that for some R-Car
>> > Gen2 early revisions there is no proper software fix. Anyway, no
>> > product has been built around early revisions, but development boards
>> > mounting early revisions (basically prototypes) are still out there.
>> > As a result, this series isn't enabling the internal watchdog on R-Car
>> > Gen2 boards, developers may enable it in board specific device trees
>> > if needed.
>> > This series has been tested by me on the iwg20d, iwg22d, Lager, Alt,
>> > and Koelsch boards.
>> >
>> > The problem
>> > ===========
>> > To deal with SMP on R-Car Gen2 and RZ/G1, we install a reset vector
>> > to ICRAM1 and we program the [S]BAR registers so that when we turn ON
>> > the non-boot CPUs they are redirected to the reset vector installed by
>> > Linux in ICRAM1, and eventually they continue the execution to RAM,
>> > where the SMP bring-up code will take care of the rest.
>> > The content of the [S]BAR registers survives a watchdog triggered reset,
>> > and as such after the watchdog fires the boot core will try and execute
>> > the SMP bring-up code instead of jumping to the bootrom code.
>> >
>> > The fix
>> > =======
>> > The main strategy for the solution is to let the reset vector decide
>> > if it needs to jump to shmobile_boot_fn or to the bootrom code.
>> > In a watchdog triggered reset scenario, since the [S]BAR registers keep
>> > their values, the boot CPU will jump into the newly designed reset
>> > vector, the assembly routine will eventually test WOVF (a bit in register
>> > RWTCSRA that indicates if the watchdog counter has overflown, the value
>> > of this bit gets retained in this scenario), and jump to the bootrom code
>> > which will in turn load up the bootloader, etc.
>> > When bringing up SMP or using CPU hotplug, the reset vector will jump
>> > to shmobile_boot_fn instead.
>> >
>> > Thank you All for your help.
>> >
>> > Best regards,
>> >
>> > Fabrizio Castro (26):
>> >   ARM: shmobile: Add watchdog support
>> >   ARM: dts: r8a7743: Adjust SMP routine size
>> >   ARM: dts: r8a7745: Adjust SMP routine size
>> >   ARM: dts: r8a7790: Adjust SMP routine size
>> >   ARM: dts: r8a7791: Adjust SMP routine size
>> >   ARM: dts: r8a7792: Adjust SMP routine size
>> >   ARM: dts: r8a7793: Adjust SMP routine size
>> >   ARM: dts: r8a7794: Adjust SMP routine size
>> >   soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2
>> >   ARM: shmobile: rcar-gen2: Add watchdog support
>> >   dt-bindings: watchdog: renesas-wdt: Add R-Car Gen2 support
>> >   watchdog: renesas_wdt: Add R-Car Gen2 support
>> >   watchdog: renesas_wdt: Add restart handler
>> >   ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN
>> >   clk: renesas: r8a7743: Add rwdt clock
>> >   clk: renesas: r8a7745: Add rwdt clock
>> >   clk: renesas: r8a7790: Add rwdt clock
>> >   clk: renesas: r8a7791/r8a7793: Add rwdt clock
>> >   clk: renesas: r8a7794: Add rwdt clock
>> >   ARM: dts: r8a7743: Add watchdog support to SoC dtsi
>> >   ARM: dts: r8a7745: Add watchdog support to SoC dtsi
>> >   ARM: dts: r8a7790: Add watchdog support to SoC dtsi
>> >   ARM: dts: r8a7791: Add watchdog support to SoC dtsi
>> >   ARM: dts: r8a7794: Add watchdog support to SoC dtsi
>> >   ARM: dts: iwg20m: Add watchdog support to SoM dtsi
>> >   ARM: dts: iwg22m: Add watchdog support to SoM dtsi
>> >
>> >  .../devicetree/bindings/watchdog/renesas-wdt.txt   | 19 ++++++--
>> >  arch/arm/boot/dts/r8a7743-iwg20m.dtsi              |  5 ++
>> >  arch/arm/boot/dts/r8a7743.dtsi                     | 12 ++++-
>> >  arch/arm/boot/dts/r8a7745-iwg22m.dtsi              |  5 ++
>> >  arch/arm/boot/dts/r8a7745.dtsi                     | 12 ++++-
>> >  arch/arm/boot/dts/r8a7790.dtsi                     | 12 ++++-
>> >  arch/arm/boot/dts/r8a7791.dtsi                     | 12 ++++-
>> >  arch/arm/boot/dts/r8a7792.dtsi                     |  2 +-
>> >  arch/arm/boot/dts/r8a7793.dtsi                     |  2 +-
>> >  arch/arm/boot/dts/r8a7794.dtsi                     | 12 ++++-
>> >  arch/arm/configs/shmobile_defconfig                |  1 +
>> >  arch/arm/mach-shmobile/common.h                    |  6 +++
>> >  arch/arm/mach-shmobile/headsmp.S                   | 55 ++++++++++++++++++++++
>> >  arch/arm/mach-shmobile/platsmp-apmu.c              |  1 +
>> >  arch/arm/mach-shmobile/pm-rcar-gen2.c              | 15 ++++--
>> >  drivers/clk/renesas/r8a7743-cpg-mssr.c             |  2 +
>> >  drivers/clk/renesas/r8a7745-cpg-mssr.c             |  2 +
>> >  drivers/clk/renesas/r8a7790-cpg-mssr.c             |  2 +
>> >  drivers/clk/renesas/r8a7791-cpg-mssr.c             |  2 +
>> >  drivers/clk/renesas/r8a7794-cpg-mssr.c             |  2 +
>> >  drivers/soc/renesas/rcar-rst.c                     | 35 +++++++++++---
>> >  drivers/watchdog/renesas_wdt.c                     | 39 +++++++++++++--
>>
>> Thanks, I've queued the clock patches in clk-renesas-for-v4.17, as they are
>> a hard dependency for:
>>   (1) The new reset vector in arch/arm/mach-shmobile/
>>   (2) The watchdog driver.
>>
>> Note that the watchdog driver itself (2) has a hard dependency on the
>> new reset vector (1).
>
> Thanks, I have marked the watchdog driver patch as Deferred.
> Please resubmit or otherwise ping me once they dependencies
> are in an rc release.

I gave the dependencies a bit more thought.

I think we can gain once release cycle if you would postpone the DTS patches
(both SMP routine size adjustments and RWDT device node additions) to v4.18.
Then all other parts can be upstreamed in parallel in v4.17, as nothing
will be activated before the DTS parts are in.

Does this look sane?
Thanks!

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1

[Simon Horman]

On Wed, Feb 21, 2018 at 05:30:12PM +0100, Geert Uytterhoeven wrote:
> Hi Simon,
> 
> On Wed, Feb 21, 2018 at 5:13 PM, Simon Horman <horms@verge.net.au> wrote:
> > On Tue, Feb 20, 2018 at 01:51:28PM +0100, Geert Uytterhoeven wrote:
> >> On Mon, Feb 12, 2018 at 6:44 PM, Fabrizio Castro
> >> <fabrizio.castro@bp.renesas.com> wrote:
> >> > this series has been around for some time as RFC, and it has collected
> >> > useful comments from the community along the way.
> >> > The solution proposed by this patch set works for most R-Car Gen2 and
> >> > RZ/G1 devices, but not all of them. We now know that for some R-Car
> >> > Gen2 early revisions there is no proper software fix. Anyway, no
> >> > product has been built around early revisions, but development boards
> >> > mounting early revisions (basically prototypes) are still out there.
> >> > As a result, this series isn't enabling the internal watchdog on R-Car
> >> > Gen2 boards, developers may enable it in board specific device trees
> >> > if needed.
> >> > This series has been tested by me on the iwg20d, iwg22d, Lager, Alt,
> >> > and Koelsch boards.
> >> >
> >> > The problem
> >> > ===========
> >> > To deal with SMP on R-Car Gen2 and RZ/G1, we install a reset vector
> >> > to ICRAM1 and we program the [S]BAR registers so that when we turn ON
> >> > the non-boot CPUs they are redirected to the reset vector installed by
> >> > Linux in ICRAM1, and eventually they continue the execution to RAM,
> >> > where the SMP bring-up code will take care of the rest.
> >> > The content of the [S]BAR registers survives a watchdog triggered reset,
> >> > and as such after the watchdog fires the boot core will try and execute
> >> > the SMP bring-up code instead of jumping to the bootrom code.
> >> >
> >> > The fix
> >> > =======
> >> > The main strategy for the solution is to let the reset vector decide
> >> > if it needs to jump to shmobile_boot_fn or to the bootrom code.
> >> > In a watchdog triggered reset scenario, since the [S]BAR registers keep
> >> > their values, the boot CPU will jump into the newly designed reset
> >> > vector, the assembly routine will eventually test WOVF (a bit in register
> >> > RWTCSRA that indicates if the watchdog counter has overflown, the value
> >> > of this bit gets retained in this scenario), and jump to the bootrom code
> >> > which will in turn load up the bootloader, etc.
> >> > When bringing up SMP or using CPU hotplug, the reset vector will jump
> >> > to shmobile_boot_fn instead.
> >> >
> >> > Thank you All for your help.
> >> >
> >> > Best regards,
> >> >
> >> > Fabrizio Castro (26):
> >> >   ARM: shmobile: Add watchdog support
> >> >   ARM: dts: r8a7743: Adjust SMP routine size
> >> >   ARM: dts: r8a7745: Adjust SMP routine size
> >> >   ARM: dts: r8a7790: Adjust SMP routine size
> >> >   ARM: dts: r8a7791: Adjust SMP routine size
> >> >   ARM: dts: r8a7792: Adjust SMP routine size
> >> >   ARM: dts: r8a7793: Adjust SMP routine size
> >> >   ARM: dts: r8a7794: Adjust SMP routine size
> >> >   soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2
> >> >   ARM: shmobile: rcar-gen2: Add watchdog support
> >> >   dt-bindings: watchdog: renesas-wdt: Add R-Car Gen2 support
> >> >   watchdog: renesas_wdt: Add R-Car Gen2 support
> >> >   watchdog: renesas_wdt: Add restart handler
> >> >   ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN
> >> >   clk: renesas: r8a7743: Add rwdt clock
> >> >   clk: renesas: r8a7745: Add rwdt clock
> >> >   clk: renesas: r8a7790: Add rwdt clock
> >> >   clk: renesas: r8a7791/r8a7793: Add rwdt clock
> >> >   clk: renesas: r8a7794: Add rwdt clock
> >> >   ARM: dts: r8a7743: Add watchdog support to SoC dtsi
> >> >   ARM: dts: r8a7745: Add watchdog support to SoC dtsi
> >> >   ARM: dts: r8a7790: Add watchdog support to SoC dtsi
> >> >   ARM: dts: r8a7791: Add watchdog support to SoC dtsi
> >> >   ARM: dts: r8a7794: Add watchdog support to SoC dtsi
> >> >   ARM: dts: iwg20m: Add watchdog support to SoM dtsi
> >> >   ARM: dts: iwg22m: Add watchdog support to SoM dtsi
> >> >
> >> >  .../devicetree/bindings/watchdog/renesas-wdt.txt   | 19 ++++++--
> >> >  arch/arm/boot/dts/r8a7743-iwg20m.dtsi              |  5 ++
> >> >  arch/arm/boot/dts/r8a7743.dtsi                     | 12 ++++-
> >> >  arch/arm/boot/dts/r8a7745-iwg22m.dtsi              |  5 ++
> >> >  arch/arm/boot/dts/r8a7745.dtsi                     | 12 ++++-
> >> >  arch/arm/boot/dts/r8a7790.dtsi                     | 12 ++++-
> >> >  arch/arm/boot/dts/r8a7791.dtsi                     | 12 ++++-
> >> >  arch/arm/boot/dts/r8a7792.dtsi                     |  2 +-
> >> >  arch/arm/boot/dts/r8a7793.dtsi                     |  2 +-
> >> >  arch/arm/boot/dts/r8a7794.dtsi                     | 12 ++++-
> >> >  arch/arm/configs/shmobile_defconfig                |  1 +
> >> >  arch/arm/mach-shmobile/common.h                    |  6 +++
> >> >  arch/arm/mach-shmobile/headsmp.S                   | 55 ++++++++++++++++++++++
> >> >  arch/arm/mach-shmobile/platsmp-apmu.c              |  1 +
> >> >  arch/arm/mach-shmobile/pm-rcar-gen2.c              | 15 ++++--
> >> >  drivers/clk/renesas/r8a7743-cpg-mssr.c             |  2 +
> >> >  drivers/clk/renesas/r8a7745-cpg-mssr.c             |  2 +
> >> >  drivers/clk/renesas/r8a7790-cpg-mssr.c             |  2 +
> >> >  drivers/clk/renesas/r8a7791-cpg-mssr.c             |  2 +
> >> >  drivers/clk/renesas/r8a7794-cpg-mssr.c             |  2 +
> >> >  drivers/soc/renesas/rcar-rst.c                     | 35 +++++++++++---
> >> >  drivers/watchdog/renesas_wdt.c                     | 39 +++++++++++++--
> >>
> >> Thanks, I've queued the clock patches in clk-renesas-for-v4.17, as they are
> >> a hard dependency for:
> >>   (1) The new reset vector in arch/arm/mach-shmobile/
> >>   (2) The watchdog driver.
> >>
> >> Note that the watchdog driver itself (2) has a hard dependency on the
> >> new reset vector (1).
> >
> > Thanks, I have marked the watchdog driver patch as Deferred.
> > Please resubmit or otherwise ping me once they dependencies
> > are in an rc release.
> 
> I gave the dependencies a bit more thought.
> 
> I think we can gain once release cycle if you would postpone the DTS patches
> (both SMP routine size adjustments and RWDT device node additions) to v4.18.
> Then all other parts can be upstreamed in parallel in v4.17, as nothing
> will be activated before the DTS parts are in.
> 
> Does this look sane?

What about new DTS on old kernels of a specific vintage?

Re: [PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1

[Geert Uytterhoeven]

Hi Simon,

On Wed, Feb 21, 2018 at 7:32 PM, Simon Horman <horms@verge.net.au> wrote:
> On Wed, Feb 21, 2018 at 05:30:12PM +0100, Geert Uytterhoeven wrote:
>> On Wed, Feb 21, 2018 at 5:13 PM, Simon Horman <horms@verge.net.au> wrote:
>> > On Tue, Feb 20, 2018 at 01:51:28PM +0100, Geert Uytterhoeven wrote:
>> >> On Mon, Feb 12, 2018 at 6:44 PM, Fabrizio Castro
>> >> <fabrizio.castro@bp.renesas.com> wrote:
>> >> > this series has been around for some time as RFC, and it has collected
>> >> > useful comments from the community along the way.
>> >> > The solution proposed by this patch set works for most R-Car Gen2 and
>> >> > RZ/G1 devices, but not all of them. We now know that for some R-Car
>> >> > Gen2 early revisions there is no proper software fix. Anyway, no
>> >> > product has been built around early revisions, but development boards
>> >> > mounting early revisions (basically prototypes) are still out there.
>> >> > As a result, this series isn't enabling the internal watchdog on R-Car
>> >> > Gen2 boards, developers may enable it in board specific device trees
>> >> > if needed.
>> >> > This series has been tested by me on the iwg20d, iwg22d, Lager, Alt,
>> >> > and Koelsch boards.
>> >> >
>> >> > The problem
>> >> > ===========
>> >> > To deal with SMP on R-Car Gen2 and RZ/G1, we install a reset vector
>> >> > to ICRAM1 and we program the [S]BAR registers so that when we turn ON
>> >> > the non-boot CPUs they are redirected to the reset vector installed by
>> >> > Linux in ICRAM1, and eventually they continue the execution to RAM,
>> >> > where the SMP bring-up code will take care of the rest.
>> >> > The content of the [S]BAR registers survives a watchdog triggered reset,
>> >> > and as such after the watchdog fires the boot core will try and execute
>> >> > the SMP bring-up code instead of jumping to the bootrom code.
>> >> >
>> >> > The fix
>> >> > =======
>> >> > The main strategy for the solution is to let the reset vector decide
>> >> > if it needs to jump to shmobile_boot_fn or to the bootrom code.
>> >> > In a watchdog triggered reset scenario, since the [S]BAR registers keep
>> >> > their values, the boot CPU will jump into the newly designed reset
>> >> > vector, the assembly routine will eventually test WOVF (a bit in register
>> >> > RWTCSRA that indicates if the watchdog counter has overflown, the value
>> >> > of this bit gets retained in this scenario), and jump to the bootrom code
>> >> > which will in turn load up the bootloader, etc.
>> >> > When bringing up SMP or using CPU hotplug, the reset vector will jump
>> >> > to shmobile_boot_fn instead.
>> >> >
>> >> > Thank you All for your help.
>> >> >
>> >> > Best regards,
>> >> >
>> >> > Fabrizio Castro (26):
>> >> >   ARM: shmobile: Add watchdog support
>> >> >   ARM: dts: r8a7743: Adjust SMP routine size
>> >> >   ARM: dts: r8a7745: Adjust SMP routine size
>> >> >   ARM: dts: r8a7790: Adjust SMP routine size
>> >> >   ARM: dts: r8a7791: Adjust SMP routine size
>> >> >   ARM: dts: r8a7792: Adjust SMP routine size
>> >> >   ARM: dts: r8a7793: Adjust SMP routine size
>> >> >   ARM: dts: r8a7794: Adjust SMP routine size
>> >> >   soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2
>> >> >   ARM: shmobile: rcar-gen2: Add watchdog support
>> >> >   dt-bindings: watchdog: renesas-wdt: Add R-Car Gen2 support
>> >> >   watchdog: renesas_wdt: Add R-Car Gen2 support
>> >> >   watchdog: renesas_wdt: Add restart handler
>> >> >   ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN
>> >> >   clk: renesas: r8a7743: Add rwdt clock
>> >> >   clk: renesas: r8a7745: Add rwdt clock
>> >> >   clk: renesas: r8a7790: Add rwdt clock
>> >> >   clk: renesas: r8a7791/r8a7793: Add rwdt clock
>> >> >   clk: renesas: r8a7794: Add rwdt clock
>> >> >   ARM: dts: r8a7743: Add watchdog support to SoC dtsi
>> >> >   ARM: dts: r8a7745: Add watchdog support to SoC dtsi
>> >> >   ARM: dts: r8a7790: Add watchdog support to SoC dtsi
>> >> >   ARM: dts: r8a7791: Add watchdog support to SoC dtsi
>> >> >   ARM: dts: r8a7794: Add watchdog support to SoC dtsi
>> >> >   ARM: dts: iwg20m: Add watchdog support to SoM dtsi
>> >> >   ARM: dts: iwg22m: Add watchdog support to SoM dtsi
>> >> >
>> >> >  .../devicetree/bindings/watchdog/renesas-wdt.txt   | 19 ++++++--
>> >> >  arch/arm/boot/dts/r8a7743-iwg20m.dtsi              |  5 ++
>> >> >  arch/arm/boot/dts/r8a7743.dtsi                     | 12 ++++-
>> >> >  arch/arm/boot/dts/r8a7745-iwg22m.dtsi              |  5 ++
>> >> >  arch/arm/boot/dts/r8a7745.dtsi                     | 12 ++++-
>> >> >  arch/arm/boot/dts/r8a7790.dtsi                     | 12 ++++-
>> >> >  arch/arm/boot/dts/r8a7791.dtsi                     | 12 ++++-
>> >> >  arch/arm/boot/dts/r8a7792.dtsi                     |  2 +-
>> >> >  arch/arm/boot/dts/r8a7793.dtsi                     |  2 +-
>> >> >  arch/arm/boot/dts/r8a7794.dtsi                     | 12 ++++-
>> >> >  arch/arm/configs/shmobile_defconfig                |  1 +
>> >> >  arch/arm/mach-shmobile/common.h                    |  6 +++
>> >> >  arch/arm/mach-shmobile/headsmp.S                   | 55 ++++++++++++++++++++++
>> >> >  arch/arm/mach-shmobile/platsmp-apmu.c              |  1 +
>> >> >  arch/arm/mach-shmobile/pm-rcar-gen2.c              | 15 ++++--
>> >> >  drivers/clk/renesas/r8a7743-cpg-mssr.c             |  2 +
>> >> >  drivers/clk/renesas/r8a7745-cpg-mssr.c             |  2 +
>> >> >  drivers/clk/renesas/r8a7790-cpg-mssr.c             |  2 +
>> >> >  drivers/clk/renesas/r8a7791-cpg-mssr.c             |  2 +
>> >> >  drivers/clk/renesas/r8a7794-cpg-mssr.c             |  2 +
>> >> >  drivers/soc/renesas/rcar-rst.c                     | 35 +++++++++++---
>> >> >  drivers/watchdog/renesas_wdt.c                     | 39 +++++++++++++--
>> >>
>> >> Thanks, I've queued the clock patches in clk-renesas-for-v4.17, as they are
>> >> a hard dependency for:
>> >>   (1) The new reset vector in arch/arm/mach-shmobile/
>> >>   (2) The watchdog driver.
>> >>
>> >> Note that the watchdog driver itself (2) has a hard dependency on the
>> >> new reset vector (1).
>> >
>> > Thanks, I have marked the watchdog driver patch as Deferred.
>> > Please resubmit or otherwise ping me once they dependencies
>> > are in an rc release.
>>
>> I gave the dependencies a bit more thought.
>>
>> I think we can gain once release cycle if you would postpone the DTS patches
>> (both SMP routine size adjustments and RWDT device node additions) to v4.18.
>> Then all other parts can be upstreamed in parallel in v4.17, as nothing
>> will be activated before the DTS parts are in.
>>
>> Does this look sane?
>
> What about new DTS on old kernels of a specific vintage?

New DTS would work fine on v4.16 and older, which don't have any of the
other patches from this series.
New DTS would work fine on v4.17, assumed all other patches from this
series get into v4.17.

The only issue would be a new DTS on a kernel that has some but not all
other patches from this series.

If we want to fast-track everything into v4.17, we need a stable branch, to be
pulled by all 5 actors (clk-renesas, mach-shmobile, soc-renesas, watchdog,
renesas-dts).

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1

[Simon Horman]

On Thu, Feb 22, 2018 at 09:38:39AM +0100, Geert Uytterhoeven wrote:
> Hi Simon,
> 
> On Wed, Feb 21, 2018 at 7:32 PM, Simon Horman <horms@verge.net.au> wrote:
> > On Wed, Feb 21, 2018 at 05:30:12PM +0100, Geert Uytterhoeven wrote:
> >> On Wed, Feb 21, 2018 at 5:13 PM, Simon Horman <horms@verge.net.au> wrote:
> >> > On Tue, Feb 20, 2018 at 01:51:28PM +0100, Geert Uytterhoeven wrote:
> >> >> On Mon, Feb 12, 2018 at 6:44 PM, Fabrizio Castro
> >> >> <fabrizio.castro@bp.renesas.com> wrote:
> >> >> > this series has been around for some time as RFC, and it has collected
> >> >> > useful comments from the community along the way.
> >> >> > The solution proposed by this patch set works for most R-Car Gen2 and
> >> >> > RZ/G1 devices, but not all of them. We now know that for some R-Car
> >> >> > Gen2 early revisions there is no proper software fix. Anyway, no
> >> >> > product has been built around early revisions, but development boards
> >> >> > mounting early revisions (basically prototypes) are still out there.
> >> >> > As a result, this series isn't enabling the internal watchdog on R-Car
> >> >> > Gen2 boards, developers may enable it in board specific device trees
> >> >> > if needed.
> >> >> > This series has been tested by me on the iwg20d, iwg22d, Lager, Alt,
> >> >> > and Koelsch boards.
> >> >> >
> >> >> > The problem
> >> >> > ===========
> >> >> > To deal with SMP on R-Car Gen2 and RZ/G1, we install a reset vector
> >> >> > to ICRAM1 and we program the [S]BAR registers so that when we turn ON
> >> >> > the non-boot CPUs they are redirected to the reset vector installed by
> >> >> > Linux in ICRAM1, and eventually they continue the execution to RAM,
> >> >> > where the SMP bring-up code will take care of the rest.
> >> >> > The content of the [S]BAR registers survives a watchdog triggered reset,
> >> >> > and as such after the watchdog fires the boot core will try and execute
> >> >> > the SMP bring-up code instead of jumping to the bootrom code.
> >> >> >
> >> >> > The fix
> >> >> > =======
> >> >> > The main strategy for the solution is to let the reset vector decide
> >> >> > if it needs to jump to shmobile_boot_fn or to the bootrom code.
> >> >> > In a watchdog triggered reset scenario, since the [S]BAR registers keep
> >> >> > their values, the boot CPU will jump into the newly designed reset
> >> >> > vector, the assembly routine will eventually test WOVF (a bit in register
> >> >> > RWTCSRA that indicates if the watchdog counter has overflown, the value
> >> >> > of this bit gets retained in this scenario), and jump to the bootrom code
> >> >> > which will in turn load up the bootloader, etc.
> >> >> > When bringing up SMP or using CPU hotplug, the reset vector will jump
> >> >> > to shmobile_boot_fn instead.
> >> >> >
> >> >> > Thank you All for your help.
> >> >> >
> >> >> > Best regards,
> >> >> >
> >> >> > Fabrizio Castro (26):
> >> >> >   ARM: shmobile: Add watchdog support
> >> >> >   ARM: dts: r8a7743: Adjust SMP routine size
> >> >> >   ARM: dts: r8a7745: Adjust SMP routine size
> >> >> >   ARM: dts: r8a7790: Adjust SMP routine size
> >> >> >   ARM: dts: r8a7791: Adjust SMP routine size
> >> >> >   ARM: dts: r8a7792: Adjust SMP routine size
> >> >> >   ARM: dts: r8a7793: Adjust SMP routine size
> >> >> >   ARM: dts: r8a7794: Adjust SMP routine size
> >> >> >   soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2
> >> >> >   ARM: shmobile: rcar-gen2: Add watchdog support
> >> >> >   dt-bindings: watchdog: renesas-wdt: Add R-Car Gen2 support
> >> >> >   watchdog: renesas_wdt: Add R-Car Gen2 support
> >> >> >   watchdog: renesas_wdt: Add restart handler
> >> >> >   ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN
> >> >> >   clk: renesas: r8a7743: Add rwdt clock
> >> >> >   clk: renesas: r8a7745: Add rwdt clock
> >> >> >   clk: renesas: r8a7790: Add rwdt clock
> >> >> >   clk: renesas: r8a7791/r8a7793: Add rwdt clock
> >> >> >   clk: renesas: r8a7794: Add rwdt clock
> >> >> >   ARM: dts: r8a7743: Add watchdog support to SoC dtsi
> >> >> >   ARM: dts: r8a7745: Add watchdog support to SoC dtsi
> >> >> >   ARM: dts: r8a7790: Add watchdog support to SoC dtsi
> >> >> >   ARM: dts: r8a7791: Add watchdog support to SoC dtsi
> >> >> >   ARM: dts: r8a7794: Add watchdog support to SoC dtsi
> >> >> >   ARM: dts: iwg20m: Add watchdog support to SoM dtsi
> >> >> >   ARM: dts: iwg22m: Add watchdog support to SoM dtsi
> >> >> >
> >> >> >  .../devicetree/bindings/watchdog/renesas-wdt.txt   | 19 ++++++--
> >> >> >  arch/arm/boot/dts/r8a7743-iwg20m.dtsi              |  5 ++
> >> >> >  arch/arm/boot/dts/r8a7743.dtsi                     | 12 ++++-
> >> >> >  arch/arm/boot/dts/r8a7745-iwg22m.dtsi              |  5 ++
> >> >> >  arch/arm/boot/dts/r8a7745.dtsi                     | 12 ++++-
> >> >> >  arch/arm/boot/dts/r8a7790.dtsi                     | 12 ++++-
> >> >> >  arch/arm/boot/dts/r8a7791.dtsi                     | 12 ++++-
> >> >> >  arch/arm/boot/dts/r8a7792.dtsi                     |  2 +-
> >> >> >  arch/arm/boot/dts/r8a7793.dtsi                     |  2 +-
> >> >> >  arch/arm/boot/dts/r8a7794.dtsi                     | 12 ++++-
> >> >> >  arch/arm/configs/shmobile_defconfig                |  1 +
> >> >> >  arch/arm/mach-shmobile/common.h                    |  6 +++
> >> >> >  arch/arm/mach-shmobile/headsmp.S                   | 55 ++++++++++++++++++++++
> >> >> >  arch/arm/mach-shmobile/platsmp-apmu.c              |  1 +
> >> >> >  arch/arm/mach-shmobile/pm-rcar-gen2.c              | 15 ++++--
> >> >> >  drivers/clk/renesas/r8a7743-cpg-mssr.c             |  2 +
> >> >> >  drivers/clk/renesas/r8a7745-cpg-mssr.c             |  2 +
> >> >> >  drivers/clk/renesas/r8a7790-cpg-mssr.c             |  2 +
> >> >> >  drivers/clk/renesas/r8a7791-cpg-mssr.c             |  2 +
> >> >> >  drivers/clk/renesas/r8a7794-cpg-mssr.c             |  2 +
> >> >> >  drivers/soc/renesas/rcar-rst.c                     | 35 +++++++++++---
> >> >> >  drivers/watchdog/renesas_wdt.c                     | 39 +++++++++++++--
> >> >>
> >> >> Thanks, I've queued the clock patches in clk-renesas-for-v4.17, as they are
> >> >> a hard dependency for:
> >> >>   (1) The new reset vector in arch/arm/mach-shmobile/
> >> >>   (2) The watchdog driver.
> >> >>
> >> >> Note that the watchdog driver itself (2) has a hard dependency on the
> >> >> new reset vector (1).
> >> >
> >> > Thanks, I have marked the watchdog driver patch as Deferred.
> >> > Please resubmit or otherwise ping me once they dependencies
> >> > are in an rc release.
> >>
> >> I gave the dependencies a bit more thought.
> >>
> >> I think we can gain once release cycle if you would postpone the DTS patches
> >> (both SMP routine size adjustments and RWDT device node additions) to v4.18.
> >> Then all other parts can be upstreamed in parallel in v4.17, as nothing
> >> will be activated before the DTS parts are in.
> >>
> >> Does this look sane?
> >
> > What about new DTS on old kernels of a specific vintage?
> 
> New DTS would work fine on v4.16 and older, which don't have any of the
> other patches from this series.
> New DTS would work fine on v4.17, assumed all other patches from this
> series get into v4.17.
> 
> The only issue would be a new DTS on a kernel that has some but not all
> other patches from this series.

Thanks for the analysis. I think this is the key point. What is the risk of
that happening?

> If we want to fast-track everything into v4.17, we need a stable branch, to be
> pulled by all 5 actors (clk-renesas, mach-shmobile, soc-renesas, watchdog,
> renesas-dts).

It seems that watchdog is the only item on that list that neither you nor I
sign off on. So I conclude that if the watchdog patch goes in early enough
in the cycle then we ought to be in good shape.

None the less, is it worth the risk?

Re: [PATCH v5 01/26] ARM: shmobile: Add watchdog support

[Geert Uytterhoeven]

Hi Fabrizio,

On Mon, Feb 12, 2018 at 6:44 PM, Fabrizio Castro
<fabrizio.castro@bp.renesas.com> wrote:
> On R-Car Gen2 and RZ/G1 platforms, we use the SBAR registers to make non
> boot CPUs run a routine designed to bring up SMP and deal with hot plug.
> The value contained in the SBAR registers is not initialized by a WDT
> triggered reset, which means that after a WDT triggered reset we jump
> to the SMP bring up routine, preventing the system from executing the
> bootrom code.
>
> The purpose of this patch is to jump to the bootrom code in case of a
> WDT triggered reset, and keep the SMP functionality untouched.
> In order to tell if the code had been called due to the WDT overflowing
> we are testing WOVF from register RWTCSRA.
>
> The new function shmobile_boot_vector_gen2 isn't replacing
> shmobile_boot_vector for backward compatibility reasons. The kernel
> will install the best option (either shmobile_boot_vector or
> shmobile_boot_vector_gen2) to ICRAM1 after parsing the device tree,
> according to the amount of memory available.
>
> Since shmobile_boot_vector has become bigger, "reg" property of nodes
> compatible with "renesas,smp-sram" now need to be set to a value
> greater or equal to "<0 0x60>".
>
> Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
> Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>

> --- a/arch/arm/mach-shmobile/common.h
> +++ b/arch/arm/mach-shmobile/common.h
> @@ -7,6 +7,12 @@ extern void shmobile_init_delay(void);
>  extern void shmobile_boot_vector(void);
>  extern unsigned long shmobile_boot_fn;
>  extern unsigned long shmobile_boot_size;
> +#ifdef CONFIG_ARCH_RCAR_GEN2

I think this #ifdef can be removed.

> +extern void shmobile_boot_vector_gen2(void);
> +extern unsigned long shmobile_boot_fn_gen2;
> +extern unsigned long shmobile_boot_cpu_gen2;
> +extern unsigned long shmobile_boot_size_gen2;
> +#endif /* CONFIG_ARCH_RCAR_GEN2 */
>  extern void shmobile_smp_boot(void);
>  extern void shmobile_smp_sleep(void);
>  extern void shmobile_smp_hook(unsigned int cpu, unsigned long fn,

Apart from that:
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

RE: [PATCH v5 01/26] ARM: shmobile: Add watchdog support

[Fabrizio Castro]

Hi Geert,

thank you for your feedback!

> Subject: Re: [PATCH v5 01/26] ARM: shmobile: Add watchdog support
>
> Hi Fabrizio,
>
> On Mon, Feb 12, 2018 at 6:44 PM, Fabrizio Castro
> <fabrizio.castro@bp.renesas.com> wrote:
> > On R-Car Gen2 and RZ/G1 platforms, we use the SBAR registers to make non
> > boot CPUs run a routine designed to bring up SMP and deal with hot plug.
> > The value contained in the SBAR registers is not initialized by a WDT
> > triggered reset, which means that after a WDT triggered reset we jump
> > to the SMP bring up routine, preventing the system from executing the
> > bootrom code.
> >
> > The purpose of this patch is to jump to the bootrom code in case of a
> > WDT triggered reset, and keep the SMP functionality untouched.
> > In order to tell if the code had been called due to the WDT overflowing
> > we are testing WOVF from register RWTCSRA.
> >
> > The new function shmobile_boot_vector_gen2 isn't replacing
> > shmobile_boot_vector for backward compatibility reasons. The kernel
> > will install the best option (either shmobile_boot_vector or
> > shmobile_boot_vector_gen2) to ICRAM1 after parsing the device tree,
> > according to the amount of memory available.
> >
> > Since shmobile_boot_vector has become bigger, "reg" property of nodes
> > compatible with "renesas,smp-sram" now need to be set to a value
> > greater or equal to "<0 0x60>".
> >
> > Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
> > Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
>
> > --- a/arch/arm/mach-shmobile/common.h
> > +++ b/arch/arm/mach-shmobile/common.h
> > @@ -7,6 +7,12 @@ extern void shmobile_init_delay(void);
> >  extern void shmobile_boot_vector(void);
> >  extern unsigned long shmobile_boot_fn;
> >  extern unsigned long shmobile_boot_size;
> > +#ifdef CONFIG_ARCH_RCAR_GEN2
>
> I think this #ifdef can be removed.

I'll send a new version of this patch without ifdefs.

Thanks,
Fab

>
> > +extern void shmobile_boot_vector_gen2(void);
> > +extern unsigned long shmobile_boot_fn_gen2;
> > +extern unsigned long shmobile_boot_cpu_gen2;
> > +extern unsigned long shmobile_boot_size_gen2;
> > +#endif /* CONFIG_ARCH_RCAR_GEN2 */
> >  extern void shmobile_smp_boot(void);
> >  extern void shmobile_smp_sleep(void);
> >  extern void shmobile_smp_hook(unsigned int cpu, unsigned long fn,
>
> Apart from that:
> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
>
> Gr{oetje,eeting}s,
>
>                         Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds



Renesas Electronics Europe Ltd, Dukes Meadow, Millboard Road, Bourne End, Buckinghamshire, SL8 5FH, UK. Registered in England & Wales under Registered No. 04586709.

[PATCH v6 01/26] ARM: shmobile: Add watchdog support

[Fabrizio Castro]

On R-Car Gen2 and RZ/G1 platforms, we use the SBAR registers to make non
boot CPUs run a routine designed to bring up SMP and deal with hot plug.
The value contained in the SBAR registers is not initialized by a WDT
triggered reset, which means that after a WDT triggered reset we jump
to the SMP bring up routine, preventing the system from executing the
bootrom code.

The purpose of this patch is to jump to the bootrom code in case of a
WDT triggered reset, and keep the SMP functionality untouched.
In order to tell if the code had been called due to the WDT overflowing
we are testing WOVF from register RWTCSRA.

The new function shmobile_boot_vector_gen2 isn't replacing
shmobile_boot_vector for backward compatibility reasons. The kernel
will install the best option (either shmobile_boot_vector or
shmobile_boot_vector_gen2) to ICRAM1 after parsing the device tree,
according to the amount of memory available.

Since shmobile_boot_vector has become bigger, "reg" property of nodes
compatible with "renesas,smp-sram" now need to be set to a value
greater or equal to "<0 0x60>".

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
v5->v6:
* taken ifdefs out as per Geert's suggestion.

 arch/arm/mach-shmobile/common.h  |  4 +++
 arch/arm/mach-shmobile/headsmp.S | 53 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 57 insertions(+)

diff --git a/arch/arm/mach-shmobile/common.h b/arch/arm/mach-shmobile/common.h
index a8fa4f7..43c1ac69 100644
--- a/arch/arm/mach-shmobile/common.h
+++ b/arch/arm/mach-shmobile/common.h
@@ -7,6 +7,10 @@ extern void shmobile_init_delay(void);
 extern void shmobile_boot_vector(void);
 extern unsigned long shmobile_boot_fn;
 extern unsigned long shmobile_boot_size;
+extern void shmobile_boot_vector_gen2(void);
+extern unsigned long shmobile_boot_fn_gen2;
+extern unsigned long shmobile_boot_cpu_gen2;
+extern unsigned long shmobile_boot_size_gen2;
 extern void shmobile_smp_boot(void);
 extern void shmobile_smp_sleep(void);
 extern void shmobile_smp_hook(unsigned int cpu, unsigned long fn,
diff --git a/arch/arm/mach-shmobile/headsmp.S b/arch/arm/mach-shmobile/headsmp.S
index 32e0bf6..2ece67c 100644
--- a/arch/arm/mach-shmobile/headsmp.S
+++ b/arch/arm/mach-shmobile/headsmp.S
@@ -16,6 +16,11 @@
 #include <asm/assembler.h>
 #include <asm/memory.h>
 
+#define SCTLR_MMU	0x01
+#define BOOTROM_ADDRESS	0xE6340000
+#define RWTCSRA_ADDRESS 0xE6020004
+#define RWTCSRA_WOVF	0x10
+
 /*
  * Reset vector for secondary CPUs.
  * This will be mapped at address 0 by SBAR register.
@@ -38,6 +43,54 @@ shmobile_boot_size:
 	.long	. - shmobile_boot_vector
 
 /*
+ * Reset vector for R-Car Gen2 and RZ/G1 secondary CPUs.
+ * This will be mapped at address 0 by SBAR register.
+ */
+ENTRY(shmobile_boot_vector_gen2)
+	mrc	p15, 0, r0, c0, c0, 5		@ r0 = MPIDR
+	ldr	r1, shmobile_boot_cpu_gen2
+	cmp	r0, r1
+	bne	shmobile_smp_continue_gen2
+
+	mrc	p15, 0, r1, c1, c0, 0		@ r1 = SCTLR
+	and	r0, r1, #SCTLR_MMU
+	cmp	r0, #SCTLR_MMU
+	beq	shmobile_smp_continue_gen2
+
+	ldr	r0, rwtcsra
+	mov	r1, #0
+	ldrb	r1, [r0]
+	and	r0, r1, #RWTCSRA_WOVF
+	cmp	r0, #RWTCSRA_WOVF
+	bne	shmobile_smp_continue_gen2
+
+	ldr	r0, bootrom
+	bx	r0
+
+shmobile_smp_continue_gen2:
+	ldr     r1, shmobile_boot_fn_gen2
+	bx	r1
+
+ENDPROC(shmobile_boot_vector_gen2)
+
+	.align	4
+rwtcsra:
+	.word	RWTCSRA_ADDRESS
+bootrom:
+	.word	BOOTROM_ADDRESS
+	.globl	shmobile_boot_cpu_gen2
+shmobile_boot_cpu_gen2:
+	.word	0x00000000
+
+	.align	2
+	.globl	shmobile_boot_fn_gen2
+shmobile_boot_fn_gen2:
+	.space	4
+	.globl	shmobile_boot_size_gen2
+shmobile_boot_size_gen2:
+	.long	. - shmobile_boot_vector_gen2
+
+/*
  * Per-CPU SMP boot function/argument selection code based on MPIDR
  */
 
-- 
2.7.4

Re: [PATCH v5 12/26] watchdog: renesas_wdt: Add R-Car Gen2 support

[Geert Uytterhoeven]

Hi Fabrizio,

On Mon, Feb 12, 2018 at 6:44 PM, Fabrizio Castro
<fabrizio.castro@bp.renesas.com> wrote:
> Due to commits:
> * "ARM: shmobile: Add watchdog support",
> * "ARM: shmobile: rcar-gen2: Add watchdog support", and
> * "soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2",
> we now have everything we needed for the watchdog to work on Gen2 and
> RZ/G1.
>
> This commit adds "renesas,rcar-gen2-wdt" as compatible string for R-Car
> Gen2 and RZ/G1, and since on those platforms the rwdt clock needs to be
> always ON, when suspending to RAM we need to explicitly disable the
> counting by clearing TME from RWTCSRA.
>
> Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
> Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>

Thanks for your patch!

I verified this works on R-Car Gen2, so
Reviewed-and-Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>

Still, more comments below...

> --- a/drivers/watchdog/renesas_wdt.c
> +++ b/drivers/watchdog/renesas_wdt.c
> @@ -203,13 +203,29 @@ static int rwdt_remove(struct platform_device *pdev)
>         return 0;
>  }
>
> -/*
> - * This driver does also fit for R-Car Gen2 (r8a779[0-4]) WDT. However, for SMP
> - * to work there, one also needs a RESET (RST) driver which does not exist yet
> - * due to HW issues. This needs to be solved before adding compatibles here.
> - */
> +static int __maybe_unused rwdt_suspend(struct device *dev)
> +{
> +       struct rwdt_priv *priv = dev_get_drvdata(dev);
> +
> +       if (watchdog_active(&priv->wdev))
> +               rwdt_write(priv, priv->cks, RWTCSRA);
> +       return 0;
> +}
> +
> +static int __maybe_unused rwdt_resume(struct device *dev)
> +{
> +       struct rwdt_priv *priv = dev_get_drvdata(dev);
> +
> +       if (watchdog_active(&priv->wdev))
> +               rwdt_write(priv, priv->cks | RWTCSRA_TME, RWTCSRA);

Writing to this register is not sufficient on R-Car Gen3, where PSCI
suspend powers down the whole SoC.  Hence all WDT register content is lost,
causing the watchdog timeout never to trigger.
Note that this issue is pre-existing, and not caused by your patch.

This can be fixed by replacing the RWTCSRA register writes in the
suspend/resume handlers by calls to rwdt_stop() resp. rwdt_start(), like is
done in the BSP in commit e406980763f18f38 ("watchdog: renesas-wdt: Support
the suspend/resume"). Note that this would cause a small change in behavior
on R-Car Gen2, where the timeout would be reset on resume, instead of
continuing where stopped before. I don't think that hurts, though.

Since I was always a bit uncomfortable with this patch doing two things at
once (1. suspend/resume, 2. "renesas,rcar-gen2-wdt" matching), I think it
would be better to take the patch from the BSP first, and add support for
"renesas,rcar-gen2-wdt" in a subsequent patch.

Does the above make sense?
Do you agree?

Thanks!

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v6 01/26] ARM: shmobile: Add watchdog support

[Simon Horman]

On Wed, Feb 28, 2018 at 05:40:22PM +0000, Fabrizio Castro wrote:
> On R-Car Gen2 and RZ/G1 platforms, we use the SBAR registers to make non
> boot CPUs run a routine designed to bring up SMP and deal with hot plug.
> The value contained in the SBAR registers is not initialized by a WDT
> triggered reset, which means that after a WDT triggered reset we jump
> to the SMP bring up routine, preventing the system from executing the
> bootrom code.
> 
> The purpose of this patch is to jump to the bootrom code in case of a
> WDT triggered reset, and keep the SMP functionality untouched.
> In order to tell if the code had been called due to the WDT overflowing
> we are testing WOVF from register RWTCSRA.
> 
> The new function shmobile_boot_vector_gen2 isn't replacing
> shmobile_boot_vector for backward compatibility reasons. The kernel
> will install the best option (either shmobile_boot_vector or
> shmobile_boot_vector_gen2) to ICRAM1 after parsing the device tree,
> according to the amount of memory available.
> 
> Since shmobile_boot_vector has become bigger, "reg" property of nodes
> compatible with "renesas,smp-sram" now need to be set to a value
> greater or equal to "<0 0x60>".
> 
> Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
> Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>

Thanks, I have marked this as deferred as I would like dependencies to
be merged first.

Re: [PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1

[Geert Uytterhoeven]

Hi Simon,

On Fri, Feb 23, 2018 at 9:14 AM, Simon Horman <horms@verge.net.au> wrote:
> On Thu, Feb 22, 2018 at 09:38:39AM +0100, Geert Uytterhoeven wrote:
>> On Wed, Feb 21, 2018 at 7:32 PM, Simon Horman <horms@verge.net.au> wrote:
>> > On Wed, Feb 21, 2018 at 05:30:12PM +0100, Geert Uytterhoeven wrote:
>> >> On Wed, Feb 21, 2018 at 5:13 PM, Simon Horman <horms@verge.net.au> wrote:
>> >> > On Tue, Feb 20, 2018 at 01:51:28PM +0100, Geert Uytterhoeven wrote:
>> >> >> On Mon, Feb 12, 2018 at 6:44 PM, Fabrizio Castro
>> >> >> <fabrizio.castro@bp.renesas.com> wrote:
>> >> >> > this series has been around for some time as RFC, and it has collected
>> >> >> > useful comments from the community along the way.
>> >> >> > The solution proposed by this patch set works for most R-Car Gen2 and
>> >> >> > RZ/G1 devices, but not all of them. We now know that for some R-Car
>> >> >> > Gen2 early revisions there is no proper software fix. Anyway, no
>> >> >> > product has been built around early revisions, but development boards
>> >> >> > mounting early revisions (basically prototypes) are still out there.
>> >> >> > As a result, this series isn't enabling the internal watchdog on R-Car
>> >> >> > Gen2 boards, developers may enable it in board specific device trees
>> >> >> > if needed.
>> >> >> > This series has been tested by me on the iwg20d, iwg22d, Lager, Alt,
>> >> >> > and Koelsch boards.
>> >> >> >
>> >> >> > The problem
>> >> >> > ===========
>> >> >> > To deal with SMP on R-Car Gen2 and RZ/G1, we install a reset vector
>> >> >> > to ICRAM1 and we program the [S]BAR registers so that when we turn ON
>> >> >> > the non-boot CPUs they are redirected to the reset vector installed by
>> >> >> > Linux in ICRAM1, and eventually they continue the execution to RAM,
>> >> >> > where the SMP bring-up code will take care of the rest.
>> >> >> > The content of the [S]BAR registers survives a watchdog triggered reset,
>> >> >> > and as such after the watchdog fires the boot core will try and execute
>> >> >> > the SMP bring-up code instead of jumping to the bootrom code.
>> >> >> >
>> >> >> > The fix
>> >> >> > =======
>> >> >> > The main strategy for the solution is to let the reset vector decide
>> >> >> > if it needs to jump to shmobile_boot_fn or to the bootrom code.
>> >> >> > In a watchdog triggered reset scenario, since the [S]BAR registers keep
>> >> >> > their values, the boot CPU will jump into the newly designed reset
>> >> >> > vector, the assembly routine will eventually test WOVF (a bit in register
>> >> >> > RWTCSRA that indicates if the watchdog counter has overflown, the value
>> >> >> > of this bit gets retained in this scenario), and jump to the bootrom code
>> >> >> > which will in turn load up the bootloader, etc.
>> >> >> > When bringing up SMP or using CPU hotplug, the reset vector will jump
>> >> >> > to shmobile_boot_fn instead.
>> >> >> >
>> >> >> > Thank you All for your help.
>> >> >> >
>> >> >> > Best regards,
>> >> >> >
>> >> >> > Fabrizio Castro (26):
>> >> >> >   ARM: shmobile: Add watchdog support
>> >> >> >   ARM: dts: r8a7743: Adjust SMP routine size
>> >> >> >   ARM: dts: r8a7745: Adjust SMP routine size
>> >> >> >   ARM: dts: r8a7790: Adjust SMP routine size
>> >> >> >   ARM: dts: r8a7791: Adjust SMP routine size
>> >> >> >   ARM: dts: r8a7792: Adjust SMP routine size
>> >> >> >   ARM: dts: r8a7793: Adjust SMP routine size
>> >> >> >   ARM: dts: r8a7794: Adjust SMP routine size
>> >> >> >   soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2
>> >> >> >   ARM: shmobile: rcar-gen2: Add watchdog support
>> >> >> >   dt-bindings: watchdog: renesas-wdt: Add R-Car Gen2 support
>> >> >> >   watchdog: renesas_wdt: Add R-Car Gen2 support
>> >> >> >   watchdog: renesas_wdt: Add restart handler
>> >> >> >   ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN
>> >> >> >   clk: renesas: r8a7743: Add rwdt clock
>> >> >> >   clk: renesas: r8a7745: Add rwdt clock
>> >> >> >   clk: renesas: r8a7790: Add rwdt clock
>> >> >> >   clk: renesas: r8a7791/r8a7793: Add rwdt clock
>> >> >> >   clk: renesas: r8a7794: Add rwdt clock
>> >> >> >   ARM: dts: r8a7743: Add watchdog support to SoC dtsi
>> >> >> >   ARM: dts: r8a7745: Add watchdog support to SoC dtsi
>> >> >> >   ARM: dts: r8a7790: Add watchdog support to SoC dtsi
>> >> >> >   ARM: dts: r8a7791: Add watchdog support to SoC dtsi
>> >> >> >   ARM: dts: r8a7794: Add watchdog support to SoC dtsi
>> >> >> >   ARM: dts: iwg20m: Add watchdog support to SoM dtsi
>> >> >> >   ARM: dts: iwg22m: Add watchdog support to SoM dtsi
>> >> >> >
>> >> >> >  .../devicetree/bindings/watchdog/renesas-wdt.txt   | 19 ++++++--
>> >> >> >  arch/arm/boot/dts/r8a7743-iwg20m.dtsi              |  5 ++
>> >> >> >  arch/arm/boot/dts/r8a7743.dtsi                     | 12 ++++-
>> >> >> >  arch/arm/boot/dts/r8a7745-iwg22m.dtsi              |  5 ++
>> >> >> >  arch/arm/boot/dts/r8a7745.dtsi                     | 12 ++++-
>> >> >> >  arch/arm/boot/dts/r8a7790.dtsi                     | 12 ++++-
>> >> >> >  arch/arm/boot/dts/r8a7791.dtsi                     | 12 ++++-
>> >> >> >  arch/arm/boot/dts/r8a7792.dtsi                     |  2 +-
>> >> >> >  arch/arm/boot/dts/r8a7793.dtsi                     |  2 +-
>> >> >> >  arch/arm/boot/dts/r8a7794.dtsi                     | 12 ++++-
>> >> >> >  arch/arm/configs/shmobile_defconfig                |  1 +
>> >> >> >  arch/arm/mach-shmobile/common.h                    |  6 +++
>> >> >> >  arch/arm/mach-shmobile/headsmp.S                   | 55 ++++++++++++++++++++++
>> >> >> >  arch/arm/mach-shmobile/platsmp-apmu.c              |  1 +
>> >> >> >  arch/arm/mach-shmobile/pm-rcar-gen2.c              | 15 ++++--
>> >> >> >  drivers/clk/renesas/r8a7743-cpg-mssr.c             |  2 +
>> >> >> >  drivers/clk/renesas/r8a7745-cpg-mssr.c             |  2 +
>> >> >> >  drivers/clk/renesas/r8a7790-cpg-mssr.c             |  2 +
>> >> >> >  drivers/clk/renesas/r8a7791-cpg-mssr.c             |  2 +
>> >> >> >  drivers/clk/renesas/r8a7794-cpg-mssr.c             |  2 +
>> >> >> >  drivers/soc/renesas/rcar-rst.c                     | 35 +++++++++++---
>> >> >> >  drivers/watchdog/renesas_wdt.c                     | 39 +++++++++++++--
>> >> >>
>> >> >> Thanks, I've queued the clock patches in clk-renesas-for-v4.17, as they are
>> >> >> a hard dependency for:
>> >> >>   (1) The new reset vector in arch/arm/mach-shmobile/
>> >> >>   (2) The watchdog driver.
>> >> >>
>> >> >> Note that the watchdog driver itself (2) has a hard dependency on the
>> >> >> new reset vector (1).
>> >> >
>> >> > Thanks, I have marked the watchdog driver patch as Deferred.
>> >> > Please resubmit or otherwise ping me once they dependencies
>> >> > are in an rc release.
>> >>
>> >> I gave the dependencies a bit more thought.
>> >>
>> >> I think we can gain once release cycle if you would postpone the DTS patches
>> >> (both SMP routine size adjustments and RWDT device node additions) to v4.18.
>> >> Then all other parts can be upstreamed in parallel in v4.17, as nothing
>> >> will be activated before the DTS parts are in.
>> >>
>> >> Does this look sane?
>> >
>> > What about new DTS on old kernels of a specific vintage?
>>
>> New DTS would work fine on v4.16 and older, which don't have any of the
>> other patches from this series.
>> New DTS would work fine on v4.17, assumed all other patches from this
>> series get into v4.17.
>>
>> The only issue would be a new DTS on a kernel that has some but not all
>> other patches from this series.
>
> Thanks for the analysis. I think this is the key point. What is the risk of
> that happening?

I think the risk is fairly low.
You control when the DTS changes go in, and also when they are backported
to LTSI.

>> If we want to fast-track everything into v4.17, we need a stable branch, to be
>> pulled by all 5 actors (clk-renesas, mach-shmobile, soc-renesas, watchdog,
>> renesas-dts).
>
> It seems that watchdog is the only item on that list that neither you nor I
> sign off on. So I conclude that if the watchdog patch goes in early enough
> in the cycle then we ought to be in good shape.
>
> None the less, is it worth the risk?

Do we want the functionality early, or can we wait until v4.19?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

RE: [PATCH v5 12/26] watchdog: renesas_wdt: Add R-Car Gen2 support

[Fabrizio Castro]

Hi Geert,

thank you for your feedback!

> Subject: Re: [PATCH v5 12/26] watchdog: renesas_wdt: Add R-Car Gen2 support
>
> Hi Fabrizio,
>
> On Mon, Feb 12, 2018 at 6:44 PM, Fabrizio Castro
> <fabrizio.castro@bp.renesas.com> wrote:
> > Due to commits:
> > * "ARM: shmobile: Add watchdog support",
> > * "ARM: shmobile: rcar-gen2: Add watchdog support", and
> > * "soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2",
> > we now have everything we needed for the watchdog to work on Gen2 and
> > RZ/G1.
> >
> > This commit adds "renesas,rcar-gen2-wdt" as compatible string for R-Car
> > Gen2 and RZ/G1, and since on those platforms the rwdt clock needs to be
> > always ON, when suspending to RAM we need to explicitly disable the
> > counting by clearing TME from RWTCSRA.
> >
> > Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
> > Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
>
> Thanks for your patch!
>
> I verified this works on R-Car Gen2, so
> Reviewed-and-Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
>
> Still, more comments below...
>
> > --- a/drivers/watchdog/renesas_wdt.c
> > +++ b/drivers/watchdog/renesas_wdt.c
> > @@ -203,13 +203,29 @@ static int rwdt_remove(struct platform_device *pdev)
> >         return 0;
> >  }
> >
> > -/*
> > - * This driver does also fit for R-Car Gen2 (r8a779[0-4]) WDT. However, for SMP
> > - * to work there, one also needs a RESET (RST) driver which does not exist yet
> > - * due to HW issues. This needs to be solved before adding compatibles here.
> > - */
> > +static int __maybe_unused rwdt_suspend(struct device *dev)
> > +{
> > +       struct rwdt_priv *priv = dev_get_drvdata(dev);
> > +
> > +       if (watchdog_active(&priv->wdev))
> > +               rwdt_write(priv, priv->cks, RWTCSRA);
> > +       return 0;
> > +}
> > +
> > +static int __maybe_unused rwdt_resume(struct device *dev)
> > +{
> > +       struct rwdt_priv *priv = dev_get_drvdata(dev);
> > +
> > +       if (watchdog_active(&priv->wdev))
> > +               rwdt_write(priv, priv->cks | RWTCSRA_TME, RWTCSRA);
>
> Writing to this register is not sufficient on R-Car Gen3, where PSCI
> suspend powers down the whole SoC.  Hence all WDT register content is lost,
> causing the watchdog timeout never to trigger.
> Note that this issue is pre-existing, and not caused by your patch.
>
> This can be fixed by replacing the RWTCSRA register writes in the
> suspend/resume handlers by calls to rwdt_stop() resp. rwdt_start(), like is
> done in the BSP in commit e406980763f18f38 ("watchdog: renesas-wdt: Support
> the suspend/resume"). Note that this would cause a small change in behavior
> on R-Car Gen2, where the timeout would be reset on resume, instead of
> continuing where stopped before. I don't think that hurts, though.

I see, well I believe we can make both of us happy by addressing Gen3
problems and preserving the original behaviour  from Gen2.

I am going to send a new series to address this shortly.

>
> Since I was always a bit uncomfortable with this patch doing two things at
> once (1. suspend/resume, 2. "renesas,rcar-gen2-wdt" matching), I think it
> would be better to take the patch from the BSP first, and add support for
> "renesas,rcar-gen2-wdt" in a subsequent patch.

I agree, I'll split the patch and submit suspend/resume first, Gen2 compatibility
next.

Thanks,
Fab

>
> Does the above make sense?
> Do you agree?
>
> Thanks!
>
> Gr{oetje,eeting}s,
>
>                         Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds



Renesas Electronics Europe Ltd, Dukes Meadow, Millboard Road, Bourne End, Buckinghamshire, SL8 5FH, UK. Registered in England & Wales under Registered No. 04586709.

Re: [PATCH v6 01/26] ARM: shmobile: Add watchdog support

[Geert Uytterhoeven]

Hi Fabrizio,

On Wed, Feb 28, 2018 at 6:40 PM, Fabrizio Castro
<fabrizio.castro@bp.renesas.com> wrote:
> On R-Car Gen2 and RZ/G1 platforms, we use the SBAR registers to make non
> boot CPUs run a routine designed to bring up SMP and deal with hot plug.
> The value contained in the SBAR registers is not initialized by a WDT
> triggered reset, which means that after a WDT triggered reset we jump
> to the SMP bring up routine, preventing the system from executing the
> bootrom code.
>
> The purpose of this patch is to jump to the bootrom code in case of a
> WDT triggered reset, and keep the SMP functionality untouched.
> In order to tell if the code had been called due to the WDT overflowing
> we are testing WOVF from register RWTCSRA.
>
> The new function shmobile_boot_vector_gen2 isn't replacing
> shmobile_boot_vector for backward compatibility reasons. The kernel
> will install the best option (either shmobile_boot_vector or
> shmobile_boot_vector_gen2) to ICRAM1 after parsing the device tree,
> according to the amount of memory available.
>
> Since shmobile_boot_vector has become bigger, "reg" property of nodes
> compatible with "renesas,smp-sram" now need to be set to a value
> greater or equal to "<0 0x60>".
>
> Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
> Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> v5->v6:
> * taken ifdefs out as per Geert's suggestion.

My intention was to remove the #ifdefs from the header file only, not
from arch/arm/mach-shmobile/headsmp.S, as the latter is used for
other SoC families, too.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1

[Simon Horman]

On Thu, Mar 01, 2018 at 11:20:11AM +0100, Geert Uytterhoeven wrote:
> Hi Simon,
> 
> On Fri, Feb 23, 2018 at 9:14 AM, Simon Horman <horms@verge.net.au> wrote:
> > On Thu, Feb 22, 2018 at 09:38:39AM +0100, Geert Uytterhoeven wrote:
> >> On Wed, Feb 21, 2018 at 7:32 PM, Simon Horman <horms@verge.net.au> wrote:
> >> > On Wed, Feb 21, 2018 at 05:30:12PM +0100, Geert Uytterhoeven wrote:
> >> >> On Wed, Feb 21, 2018 at 5:13 PM, Simon Horman <horms@verge.net.au> wrote:
> >> >> > On Tue, Feb 20, 2018 at 01:51:28PM +0100, Geert Uytterhoeven wrote:
> >> >> >> On Mon, Feb 12, 2018 at 6:44 PM, Fabrizio Castro
> >> >> >> <fabrizio.castro@bp.renesas.com> wrote:
> >> >> >> > this series has been around for some time as RFC, and it has collected
> >> >> >> > useful comments from the community along the way.
> >> >> >> > The solution proposed by this patch set works for most R-Car Gen2 and
> >> >> >> > RZ/G1 devices, but not all of them. We now know that for some R-Car
> >> >> >> > Gen2 early revisions there is no proper software fix. Anyway, no
> >> >> >> > product has been built around early revisions, but development boards
> >> >> >> > mounting early revisions (basically prototypes) are still out there.
> >> >> >> > As a result, this series isn't enabling the internal watchdog on R-Car
> >> >> >> > Gen2 boards, developers may enable it in board specific device trees
> >> >> >> > if needed.
> >> >> >> > This series has been tested by me on the iwg20d, iwg22d, Lager, Alt,
> >> >> >> > and Koelsch boards.
> >> >> >> >
> >> >> >> > The problem
> >> >> >> > ===========
> >> >> >> > To deal with SMP on R-Car Gen2 and RZ/G1, we install a reset vector
> >> >> >> > to ICRAM1 and we program the [S]BAR registers so that when we turn ON
> >> >> >> > the non-boot CPUs they are redirected to the reset vector installed by
> >> >> >> > Linux in ICRAM1, and eventually they continue the execution to RAM,
> >> >> >> > where the SMP bring-up code will take care of the rest.
> >> >> >> > The content of the [S]BAR registers survives a watchdog triggered reset,
> >> >> >> > and as such after the watchdog fires the boot core will try and execute
> >> >> >> > the SMP bring-up code instead of jumping to the bootrom code.
> >> >> >> >
> >> >> >> > The fix
> >> >> >> > =======
> >> >> >> > The main strategy for the solution is to let the reset vector decide
> >> >> >> > if it needs to jump to shmobile_boot_fn or to the bootrom code.
> >> >> >> > In a watchdog triggered reset scenario, since the [S]BAR registers keep
> >> >> >> > their values, the boot CPU will jump into the newly designed reset
> >> >> >> > vector, the assembly routine will eventually test WOVF (a bit in register
> >> >> >> > RWTCSRA that indicates if the watchdog counter has overflown, the value
> >> >> >> > of this bit gets retained in this scenario), and jump to the bootrom code
> >> >> >> > which will in turn load up the bootloader, etc.
> >> >> >> > When bringing up SMP or using CPU hotplug, the reset vector will jump
> >> >> >> > to shmobile_boot_fn instead.
> >> >> >> >
> >> >> >> > Thank you All for your help.
> >> >> >> >
> >> >> >> > Best regards,
> >> >> >> >
> >> >> >> > Fabrizio Castro (26):
> >> >> >> >   ARM: shmobile: Add watchdog support
> >> >> >> >   ARM: dts: r8a7743: Adjust SMP routine size
> >> >> >> >   ARM: dts: r8a7745: Adjust SMP routine size
> >> >> >> >   ARM: dts: r8a7790: Adjust SMP routine size
> >> >> >> >   ARM: dts: r8a7791: Adjust SMP routine size
> >> >> >> >   ARM: dts: r8a7792: Adjust SMP routine size
> >> >> >> >   ARM: dts: r8a7793: Adjust SMP routine size
> >> >> >> >   ARM: dts: r8a7794: Adjust SMP routine size
> >> >> >> >   soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2
> >> >> >> >   ARM: shmobile: rcar-gen2: Add watchdog support
> >> >> >> >   dt-bindings: watchdog: renesas-wdt: Add R-Car Gen2 support
> >> >> >> >   watchdog: renesas_wdt: Add R-Car Gen2 support
> >> >> >> >   watchdog: renesas_wdt: Add restart handler
> >> >> >> >   ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN
> >> >> >> >   clk: renesas: r8a7743: Add rwdt clock
> >> >> >> >   clk: renesas: r8a7745: Add rwdt clock
> >> >> >> >   clk: renesas: r8a7790: Add rwdt clock
> >> >> >> >   clk: renesas: r8a7791/r8a7793: Add rwdt clock
> >> >> >> >   clk: renesas: r8a7794: Add rwdt clock
> >> >> >> >   ARM: dts: r8a7743: Add watchdog support to SoC dtsi
> >> >> >> >   ARM: dts: r8a7745: Add watchdog support to SoC dtsi
> >> >> >> >   ARM: dts: r8a7790: Add watchdog support to SoC dtsi
> >> >> >> >   ARM: dts: r8a7791: Add watchdog support to SoC dtsi
> >> >> >> >   ARM: dts: r8a7794: Add watchdog support to SoC dtsi
> >> >> >> >   ARM: dts: iwg20m: Add watchdog support to SoM dtsi
> >> >> >> >   ARM: dts: iwg22m: Add watchdog support to SoM dtsi
> >> >> >> >
> >> >> >> >  .../devicetree/bindings/watchdog/renesas-wdt.txt   | 19 ++++++--
> >> >> >> >  arch/arm/boot/dts/r8a7743-iwg20m.dtsi              |  5 ++
> >> >> >> >  arch/arm/boot/dts/r8a7743.dtsi                     | 12 ++++-
> >> >> >> >  arch/arm/boot/dts/r8a7745-iwg22m.dtsi              |  5 ++
> >> >> >> >  arch/arm/boot/dts/r8a7745.dtsi                     | 12 ++++-
> >> >> >> >  arch/arm/boot/dts/r8a7790.dtsi                     | 12 ++++-
> >> >> >> >  arch/arm/boot/dts/r8a7791.dtsi                     | 12 ++++-
> >> >> >> >  arch/arm/boot/dts/r8a7792.dtsi                     |  2 +-
> >> >> >> >  arch/arm/boot/dts/r8a7793.dtsi                     |  2 +-
> >> >> >> >  arch/arm/boot/dts/r8a7794.dtsi                     | 12 ++++-
> >> >> >> >  arch/arm/configs/shmobile_defconfig                |  1 +
> >> >> >> >  arch/arm/mach-shmobile/common.h                    |  6 +++
> >> >> >> >  arch/arm/mach-shmobile/headsmp.S                   | 55 ++++++++++++++++++++++
> >> >> >> >  arch/arm/mach-shmobile/platsmp-apmu.c              |  1 +
> >> >> >> >  arch/arm/mach-shmobile/pm-rcar-gen2.c              | 15 ++++--
> >> >> >> >  drivers/clk/renesas/r8a7743-cpg-mssr.c             |  2 +
> >> >> >> >  drivers/clk/renesas/r8a7745-cpg-mssr.c             |  2 +
> >> >> >> >  drivers/clk/renesas/r8a7790-cpg-mssr.c             |  2 +
> >> >> >> >  drivers/clk/renesas/r8a7791-cpg-mssr.c             |  2 +
> >> >> >> >  drivers/clk/renesas/r8a7794-cpg-mssr.c             |  2 +
> >> >> >> >  drivers/soc/renesas/rcar-rst.c                     | 35 +++++++++++---
> >> >> >> >  drivers/watchdog/renesas_wdt.c                     | 39 +++++++++++++--
> >> >> >>
> >> >> >> Thanks, I've queued the clock patches in clk-renesas-for-v4.17, as they are
> >> >> >> a hard dependency for:
> >> >> >>   (1) The new reset vector in arch/arm/mach-shmobile/
> >> >> >>   (2) The watchdog driver.
> >> >> >>
> >> >> >> Note that the watchdog driver itself (2) has a hard dependency on the
> >> >> >> new reset vector (1).
> >> >> >
> >> >> > Thanks, I have marked the watchdog driver patch as Deferred.
> >> >> > Please resubmit or otherwise ping me once they dependencies
> >> >> > are in an rc release.
> >> >>
> >> >> I gave the dependencies a bit more thought.
> >> >>
> >> >> I think we can gain once release cycle if you would postpone the DTS patches
> >> >> (both SMP routine size adjustments and RWDT device node additions) to v4.18.
> >> >> Then all other parts can be upstreamed in parallel in v4.17, as nothing
> >> >> will be activated before the DTS parts are in.
> >> >>
> >> >> Does this look sane?
> >> >
> >> > What about new DTS on old kernels of a specific vintage?
> >>
> >> New DTS would work fine on v4.16 and older, which don't have any of the
> >> other patches from this series.
> >> New DTS would work fine on v4.17, assumed all other patches from this
> >> series get into v4.17.
> >>
> >> The only issue would be a new DTS on a kernel that has some but not all
> >> other patches from this series.
> >
> > Thanks for the analysis. I think this is the key point. What is the risk of
> > that happening?
> 
> I think the risk is fairly low.
> You control when the DTS changes go in, and also when they are backported
> to LTSI.
> 
> >> If we want to fast-track everything into v4.17, we need a stable branch, to be
> >> pulled by all 5 actors (clk-renesas, mach-shmobile, soc-renesas, watchdog,
> >> renesas-dts).
> >
> > It seems that watchdog is the only item on that list that neither you nor I
> > sign off on. So I conclude that if the watchdog patch goes in early enough
> > in the cycle then we ought to be in good shape.
> >
> > None the less, is it worth the risk?
> 
> Do we want the functionality early, or can we wait until v4.19?

I understand that the watchdog driver has been accepted and that as things
currently stand if it is enabled in the build it will be enabled in DT and
a crash will result. From my POV that is a regression so I have decided
to adopt the alternate plan proposed by Geert above: in short drop DT
patches (to avoid enabling broken driver) and enqueue mach-shmobile
patches (which don't make things any worse.

Patch-by-patch things are as follows.

Dropped from "[PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1":

979d28f29742 ARM: dts: r8a7743: Adjust SMP routine size
0b205f679f5d ARM: dts: r8a7745: Adjust SMP routine size
2ad21a1d78b3 ARM: dts: r8a7790: Adjust SMP routine size
82c978459c77 ARM: dts: r8a7791: Adjust SMP routine size
d303698e6ff3 ARM: dts: r8a7792: Adjust SMP routine size
d8b8b9a1e295 ARM: dts: r8a7793: Adjust SMP routine size
70b3ab369773 ARM: dts: r8a7794: Adjust SMP routine size

ebf26cf1b1de ARM: dts: r8a7743: Add watchdog support to SoC dtsi
5a4566ab3777 ARM: dts: r8a7745: Add watchdog support to SoC dtsi
acd58e2bb1e5 ARM: dts: r8a7790: Add watchdog support to SoC dtsi
e3f89168e72f ARM: dts: r8a7791: Add watchdog support to SoC dtsi
e76a6a69a1fc ARM: dts: r8a7794: Add watchdog support to SoC dtsi
242cc1ab7f7c ARM: dts: iwg20m: Add watchdog support to SoM dtsi
748ed07f6c7c ARM: dts: iwg22m: Add watchdog support to SoM dtsi


Dropped from "[PATCH/RFC 00/11] ARM: dts: rcar-gen2: Enable watchdog support":

c257202482e2 ARM: dts: r8a7792: Add RWDT node
01ec04dec8eb ARM: dts: r8a7793: Add RWDT node
8e6ebe4f2f94 ARM: dts: lager: Enable watchdog support
f223ad0198f6 ARM: dts: koelsch: Enable watchdog support
1d14d2bb700d ARM: dts: porter: Enable watchdog support
bf71652fc955 ARM: dts: blanche: Enable watchdog support
13a0b10aeea4 ARM: dts: wheat: Enable watchdog support
4e247bf110b8 ARM: dts: gose: Enable watchdog support
2dcbd24bbf5e ARM: dts: alt: Enable watchdog support
7f6844c900b4 ARM: dts: silk: Enable watchdog support

And applied:

[v5] ARM: shmobile: rcar-gen2: Add watchdog support
[v5] ARM: shmobile: Add watchdog support

In the case of the last patch above I removed the #ifdef from the header file.

Re: [PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1

[Geert Uytterhoeven]

Hi Simon,

On Tue, Mar 13, 2018 at 9:05 PM, Simon Horman <horms@verge.net.au> wrote:
> On Thu, Mar 01, 2018 at 11:20:11AM +0100, Geert Uytterhoeven wrote:
>> On Fri, Feb 23, 2018 at 9:14 AM, Simon Horman <horms@verge.net.au> wrote:
>> > On Thu, Feb 22, 2018 at 09:38:39AM +0100, Geert Uytterhoeven wrote:
>> >> On Wed, Feb 21, 2018 at 7:32 PM, Simon Horman <horms@verge.net.au> wrote:
>> >> > On Wed, Feb 21, 2018 at 05:30:12PM +0100, Geert Uytterhoeven wrote:
>> >> >> On Wed, Feb 21, 2018 at 5:13 PM, Simon Horman <horms@verge.net.au> wrote:
>> >> >> > On Tue, Feb 20, 2018 at 01:51:28PM +0100, Geert Uytterhoeven wrote:
>> >> >> >> On Mon, Feb 12, 2018 at 6:44 PM, Fabrizio Castro
>> >> >> >> <fabrizio.castro@bp.renesas.com> wrote:
>> >> >> >> > this series has been around for some time as RFC, and it has collected
>> >> >> >> > useful comments from the community along the way.
>> >> >> >> > The solution proposed by this patch set works for most R-Car Gen2 and
>> >> >> >> > RZ/G1 devices, but not all of them. We now know that for some R-Car
>> >> >> >> > Gen2 early revisions there is no proper software fix. Anyway, no
>> >> >> >> > product has been built around early revisions, but development boards
>> >> >> >> > mounting early revisions (basically prototypes) are still out there.
>> >> >> >> > As a result, this series isn't enabling the internal watchdog on R-Car
>> >> >> >> > Gen2 boards, developers may enable it in board specific device trees
>> >> >> >> > if needed.
>> >> >> >> > This series has been tested by me on the iwg20d, iwg22d, Lager, Alt,
>> >> >> >> > and Koelsch boards.
>> >> >> >> >
>> >> >> >> > The problem
>> >> >> >> > ===========
>> >> >> >> > To deal with SMP on R-Car Gen2 and RZ/G1, we install a reset vector
>> >> >> >> > to ICRAM1 and we program the [S]BAR registers so that when we turn ON
>> >> >> >> > the non-boot CPUs they are redirected to the reset vector installed by
>> >> >> >> > Linux in ICRAM1, and eventually they continue the execution to RAM,
>> >> >> >> > where the SMP bring-up code will take care of the rest.
>> >> >> >> > The content of the [S]BAR registers survives a watchdog triggered reset,
>> >> >> >> > and as such after the watchdog fires the boot core will try and execute
>> >> >> >> > the SMP bring-up code instead of jumping to the bootrom code.
>> >> >> >> >
>> >> >> >> > The fix
>> >> >> >> > =======
>> >> >> >> > The main strategy for the solution is to let the reset vector decide
>> >> >> >> > if it needs to jump to shmobile_boot_fn or to the bootrom code.
>> >> >> >> > In a watchdog triggered reset scenario, since the [S]BAR registers keep
>> >> >> >> > their values, the boot CPU will jump into the newly designed reset
>> >> >> >> > vector, the assembly routine will eventually test WOVF (a bit in register
>> >> >> >> > RWTCSRA that indicates if the watchdog counter has overflown, the value
>> >> >> >> > of this bit gets retained in this scenario), and jump to the bootrom code
>> >> >> >> > which will in turn load up the bootloader, etc.
>> >> >> >> > When bringing up SMP or using CPU hotplug, the reset vector will jump
>> >> >> >> > to shmobile_boot_fn instead.
>> >> >> >> >
>> >> >> >> > Thank you All for your help.
>> >> >> >> >
>> >> >> >> > Best regards,
>> >> >> >> >
>> >> >> >> > Fabrizio Castro (26):
>> >> >> >> >   ARM: shmobile: Add watchdog support
>> >> >> >> >   ARM: dts: r8a7743: Adjust SMP routine size
>> >> >> >> >   ARM: dts: r8a7745: Adjust SMP routine size
>> >> >> >> >   ARM: dts: r8a7790: Adjust SMP routine size
>> >> >> >> >   ARM: dts: r8a7791: Adjust SMP routine size
>> >> >> >> >   ARM: dts: r8a7792: Adjust SMP routine size
>> >> >> >> >   ARM: dts: r8a7793: Adjust SMP routine size
>> >> >> >> >   ARM: dts: r8a7794: Adjust SMP routine size
>> >> >> >> >   soc: renesas: rcar-rst: Enable watchdog as reset trigger for Gen2
>> >> >> >> >   ARM: shmobile: rcar-gen2: Add watchdog support
>> >> >> >> >   dt-bindings: watchdog: renesas-wdt: Add R-Car Gen2 support
>> >> >> >> >   watchdog: renesas_wdt: Add R-Car Gen2 support
>> >> >> >> >   watchdog: renesas_wdt: Add restart handler
>> >> >> >> >   ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN
>> >> >> >> >   clk: renesas: r8a7743: Add rwdt clock
>> >> >> >> >   clk: renesas: r8a7745: Add rwdt clock
>> >> >> >> >   clk: renesas: r8a7790: Add rwdt clock
>> >> >> >> >   clk: renesas: r8a7791/r8a7793: Add rwdt clock
>> >> >> >> >   clk: renesas: r8a7794: Add rwdt clock
>> >> >> >> >   ARM: dts: r8a7743: Add watchdog support to SoC dtsi
>> >> >> >> >   ARM: dts: r8a7745: Add watchdog support to SoC dtsi
>> >> >> >> >   ARM: dts: r8a7790: Add watchdog support to SoC dtsi
>> >> >> >> >   ARM: dts: r8a7791: Add watchdog support to SoC dtsi
>> >> >> >> >   ARM: dts: r8a7794: Add watchdog support to SoC dtsi
>> >> >> >> >   ARM: dts: iwg20m: Add watchdog support to SoM dtsi
>> >> >> >> >   ARM: dts: iwg22m: Add watchdog support to SoM dtsi
>> >> >> >> >
>> >> >> >> >  .../devicetree/bindings/watchdog/renesas-wdt.txt   | 19 ++++++--
>> >> >> >> >  arch/arm/boot/dts/r8a7743-iwg20m.dtsi              |  5 ++
>> >> >> >> >  arch/arm/boot/dts/r8a7743.dtsi                     | 12 ++++-
>> >> >> >> >  arch/arm/boot/dts/r8a7745-iwg22m.dtsi              |  5 ++
>> >> >> >> >  arch/arm/boot/dts/r8a7745.dtsi                     | 12 ++++-
>> >> >> >> >  arch/arm/boot/dts/r8a7790.dtsi                     | 12 ++++-
>> >> >> >> >  arch/arm/boot/dts/r8a7791.dtsi                     | 12 ++++-
>> >> >> >> >  arch/arm/boot/dts/r8a7792.dtsi                     |  2 +-
>> >> >> >> >  arch/arm/boot/dts/r8a7793.dtsi                     |  2 +-
>> >> >> >> >  arch/arm/boot/dts/r8a7794.dtsi                     | 12 ++++-
>> >> >> >> >  arch/arm/configs/shmobile_defconfig                |  1 +
>> >> >> >> >  arch/arm/mach-shmobile/common.h                    |  6 +++
>> >> >> >> >  arch/arm/mach-shmobile/headsmp.S                   | 55 ++++++++++++++++++++++
>> >> >> >> >  arch/arm/mach-shmobile/platsmp-apmu.c              |  1 +
>> >> >> >> >  arch/arm/mach-shmobile/pm-rcar-gen2.c              | 15 ++++--
>> >> >> >> >  drivers/clk/renesas/r8a7743-cpg-mssr.c             |  2 +
>> >> >> >> >  drivers/clk/renesas/r8a7745-cpg-mssr.c             |  2 +
>> >> >> >> >  drivers/clk/renesas/r8a7790-cpg-mssr.c             |  2 +
>> >> >> >> >  drivers/clk/renesas/r8a7791-cpg-mssr.c             |  2 +
>> >> >> >> >  drivers/clk/renesas/r8a7794-cpg-mssr.c             |  2 +
>> >> >> >> >  drivers/soc/renesas/rcar-rst.c                     | 35 +++++++++++---
>> >> >> >> >  drivers/watchdog/renesas_wdt.c                     | 39 +++++++++++++--
>> >> >> >>
>> >> >> >> Thanks, I've queued the clock patches in clk-renesas-for-v4.17, as they are
>> >> >> >> a hard dependency for:
>> >> >> >>   (1) The new reset vector in arch/arm/mach-shmobile/
>> >> >> >>   (2) The watchdog driver.
>> >> >> >>
>> >> >> >> Note that the watchdog driver itself (2) has a hard dependency on the
>> >> >> >> new reset vector (1).
>> >> >> >
>> >> >> > Thanks, I have marked the watchdog driver patch as Deferred.
>> >> >> > Please resubmit or otherwise ping me once they dependencies
>> >> >> > are in an rc release.
>> >> >>
>> >> >> I gave the dependencies a bit more thought.
>> >> >>
>> >> >> I think we can gain once release cycle if you would postpone the DTS patches
>> >> >> (both SMP routine size adjustments and RWDT device node additions) to v4.18.
>> >> >> Then all other parts can be upstreamed in parallel in v4.17, as nothing
>> >> >> will be activated before the DTS parts are in.
>> >> >>
>> >> >> Does this look sane?
>> >> >
>> >> > What about new DTS on old kernels of a specific vintage?
>> >>
>> >> New DTS would work fine on v4.16 and older, which don't have any of the
>> >> other patches from this series.
>> >> New DTS would work fine on v4.17, assumed all other patches from this
>> >> series get into v4.17.
>> >>
>> >> The only issue would be a new DTS on a kernel that has some but not all
>> >> other patches from this series.
>> >
>> > Thanks for the analysis. I think this is the key point. What is the risk of
>> > that happening?
>>
>> I think the risk is fairly low.
>> You control when the DTS changes go in, and also when they are backported
>> to LTSI.
>>
>> >> If we want to fast-track everything into v4.17, we need a stable branch, to be
>> >> pulled by all 5 actors (clk-renesas, mach-shmobile, soc-renesas, watchdog,
>> >> renesas-dts).
>> >
>> > It seems that watchdog is the only item on that list that neither you nor I
>> > sign off on. So I conclude that if the watchdog patch goes in early enough
>> > in the cycle then we ought to be in good shape.
>> >
>> > None the less, is it worth the risk?
>>
>> Do we want the functionality early, or can we wait until v4.19?
>
> I understand that the watchdog driver has been accepted and that as things
> currently stand if it is enabled in the build it will be enabled in DT and
> a crash will result. From my POV that is a regression so I have decided
> to adopt the alternate plan proposed by Geert above: in short drop DT
> patches (to avoid enabling broken driver) and enqueue mach-shmobile
> patches (which don't make things any worse.
>
> Patch-by-patch things are as follows.
>
> Dropped from "[PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1":
>
> 979d28f29742 ARM: dts: r8a7743: Adjust SMP routine size
> 0b205f679f5d ARM: dts: r8a7745: Adjust SMP routine size
> 2ad21a1d78b3 ARM: dts: r8a7790: Adjust SMP routine size
> 82c978459c77 ARM: dts: r8a7791: Adjust SMP routine size
> d303698e6ff3 ARM: dts: r8a7792: Adjust SMP routine size
> d8b8b9a1e295 ARM: dts: r8a7793: Adjust SMP routine size
> 70b3ab369773 ARM: dts: r8a7794: Adjust SMP routine size
>
> ebf26cf1b1de ARM: dts: r8a7743: Add watchdog support to SoC dtsi
> 5a4566ab3777 ARM: dts: r8a7745: Add watchdog support to SoC dtsi
> acd58e2bb1e5 ARM: dts: r8a7790: Add watchdog support to SoC dtsi
> e3f89168e72f ARM: dts: r8a7791: Add watchdog support to SoC dtsi
> e76a6a69a1fc ARM: dts: r8a7794: Add watchdog support to SoC dtsi
> 242cc1ab7f7c ARM: dts: iwg20m: Add watchdog support to SoM dtsi
> 748ed07f6c7c ARM: dts: iwg22m: Add watchdog support to SoM dtsi
>
>
> Dropped from "[PATCH/RFC 00/11] ARM: dts: rcar-gen2: Enable watchdog support":
>
> c257202482e2 ARM: dts: r8a7792: Add RWDT node
> 01ec04dec8eb ARM: dts: r8a7793: Add RWDT node
> 8e6ebe4f2f94 ARM: dts: lager: Enable watchdog support
> f223ad0198f6 ARM: dts: koelsch: Enable watchdog support
> 1d14d2bb700d ARM: dts: porter: Enable watchdog support
> bf71652fc955 ARM: dts: blanche: Enable watchdog support
> 13a0b10aeea4 ARM: dts: wheat: Enable watchdog support
> 4e247bf110b8 ARM: dts: gose: Enable watchdog support
> 2dcbd24bbf5e ARM: dts: alt: Enable watchdog support
> 7f6844c900b4 ARM: dts: silk: Enable watchdog support
>
> And applied:
>
> [v5] ARM: shmobile: rcar-gen2: Add watchdog support
> [v5] ARM: shmobile: Add watchdog support
>
> In the case of the last patch above I removed the #ifdef from the header file.

Thank you, sounds good to me.

BTW, who will take "dt-bindings: watchdog: renesas-wdt: Add R-Car Gen2 support"?
Günter, Wim: will you take this through the watchdog tree, too?

Thanks again!

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

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RE: [PATCH v6 01/26] ARM: shmobile: Add watchdog support

[Fabrizio Castro]

Hi Geert,

> Subject: Re: [PATCH v6 01/26] ARM: shmobile: Add watchdog support
>
> Hi Fabrizio,
>
> On Wed, Feb 28, 2018 at 6:40 PM, Fabrizio Castro
> <fabrizio.castro@bp.renesas.com> wrote:
> > On R-Car Gen2 and RZ/G1 platforms, we use the SBAR registers to make non
> > boot CPUs run a routine designed to bring up SMP and deal with hot plug.
> > The value contained in the SBAR registers is not initialized by a WDT
> > triggered reset, which means that after a WDT triggered reset we jump
> > to the SMP bring up routine, preventing the system from executing the
> > bootrom code.
> >
> > The purpose of this patch is to jump to the bootrom code in case of a
> > WDT triggered reset, and keep the SMP functionality untouched.
> > In order to tell if the code had been called due to the WDT overflowing
> > we are testing WOVF from register RWTCSRA.
> >
> > The new function shmobile_boot_vector_gen2 isn't replacing
> > shmobile_boot_vector for backward compatibility reasons. The kernel
> > will install the best option (either shmobile_boot_vector or
> > shmobile_boot_vector_gen2) to ICRAM1 after parsing the device tree,
> > according to the amount of memory available.
> >
> > Since shmobile_boot_vector has become bigger, "reg" property of nodes
> > compatible with "renesas,smp-sram" now need to be set to a value
> > greater or equal to "<0 0x60>".
> >
> > Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
> > Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
> > Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
> > ---
> > v5->v6:
> > * taken ifdefs out as per Geert's suggestion.
>
> My intention was to remove the #ifdefs from the header file only, not
> from arch/arm/mach-shmobile/headsmp.S, as the latter is used for
> other SoC families, too.

Ah ok, I'll send another version to restore the ifdef within headsmp.S then.

Thanks,
Fab

>
> Gr{oetje,eeting}s,
>
>                         Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds



Renesas Electronics Europe Ltd, Dukes Meadow, Millboard Road, Bourne End, Buckinghamshire, SL8 5FH, UK. Registered in England & Wales under Registered No. 04586709.

Re: [PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1

[Geert Uytterhoeven]

Hi Simon,

On Tue, Mar 13, 2018 at 9:05 PM, Simon Horman <horms@verge.net.au> wrote:
> I understand that the watchdog driver has been accepted and that as things
> currently stand if it is enabled in the build it will be enabled in DT and
> a crash will result. From my POV that is a regression so I have decided
> to adopt the alternate plan proposed by Geert above: in short drop DT
> patches (to avoid enabling broken driver) and enqueue mach-shmobile
> patches (which don't make things any worse.
>
> Patch-by-patch things are as follows.
>
> Dropped from "[PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1":
>
> 979d28f29742 ARM: dts: r8a7743: Adjust SMP routine size
> 0b205f679f5d ARM: dts: r8a7745: Adjust SMP routine size
> 2ad21a1d78b3 ARM: dts: r8a7790: Adjust SMP routine size
> 82c978459c77 ARM: dts: r8a7791: Adjust SMP routine size
> d303698e6ff3 ARM: dts: r8a7792: Adjust SMP routine size
> d8b8b9a1e295 ARM: dts: r8a7793: Adjust SMP routine size
> 70b3ab369773 ARM: dts: r8a7794: Adjust SMP routine size
>
> ebf26cf1b1de ARM: dts: r8a7743: Add watchdog support to SoC dtsi
> 5a4566ab3777 ARM: dts: r8a7745: Add watchdog support to SoC dtsi
> acd58e2bb1e5 ARM: dts: r8a7790: Add watchdog support to SoC dtsi
> e3f89168e72f ARM: dts: r8a7791: Add watchdog support to SoC dtsi
> e76a6a69a1fc ARM: dts: r8a7794: Add watchdog support to SoC dtsi
> 242cc1ab7f7c ARM: dts: iwg20m: Add watchdog support to SoM dtsi
> 748ed07f6c7c ARM: dts: iwg22m: Add watchdog support to SoM dtsi
>
>
> Dropped from "[PATCH/RFC 00/11] ARM: dts: rcar-gen2: Enable watchdog support":
>
> c257202482e2 ARM: dts: r8a7792: Add RWDT node
> 01ec04dec8eb ARM: dts: r8a7793: Add RWDT node
> 8e6ebe4f2f94 ARM: dts: lager: Enable watchdog support
> f223ad0198f6 ARM: dts: koelsch: Enable watchdog support
> 1d14d2bb700d ARM: dts: porter: Enable watchdog support
> bf71652fc955 ARM: dts: blanche: Enable watchdog support
> 13a0b10aeea4 ARM: dts: wheat: Enable watchdog support
> 4e247bf110b8 ARM: dts: gose: Enable watchdog support
> 2dcbd24bbf5e ARM: dts: alt: Enable watchdog support
> 7f6844c900b4 ARM: dts: silk: Enable watchdog support
>
> And applied:
>
> [v5] ARM: shmobile: rcar-gen2: Add watchdog support
> [v5] ARM: shmobile: Add watchdog support
>
> In the case of the last patch above I removed the #ifdef from the header file.

I guess the time is ripe to apply the DTS patches again, in the following order:
  1. SMP routine size adjustments,
  2. Watchdog support additions to dtsi,
  3. Watchdog enablement for dts?

Thanks!

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1

[Simon Horman]

On Wed, Apr 18, 2018 at 03:37:29PM +0200, Geert Uytterhoeven wrote:
> Hi Simon,
> 
> On Tue, Mar 13, 2018 at 9:05 PM, Simon Horman <horms@verge.net.au> wrote:
> > I understand that the watchdog driver has been accepted and that as things
> > currently stand if it is enabled in the build it will be enabled in DT and
> > a crash will result. From my POV that is a regression so I have decided
> > to adopt the alternate plan proposed by Geert above: in short drop DT
> > patches (to avoid enabling broken driver) and enqueue mach-shmobile
> > patches (which don't make things any worse.
> >
> > Patch-by-patch things are as follows.
> >
> > Dropped from "[PATCH v5 00/26] Fix watchdog on Renesas R-Car Gen2 and RZ/G1":
> >
> > 979d28f29742 ARM: dts: r8a7743: Adjust SMP routine size
> > 0b205f679f5d ARM: dts: r8a7745: Adjust SMP routine size
> > 2ad21a1d78b3 ARM: dts: r8a7790: Adjust SMP routine size
> > 82c978459c77 ARM: dts: r8a7791: Adjust SMP routine size
> > d303698e6ff3 ARM: dts: r8a7792: Adjust SMP routine size
> > d8b8b9a1e295 ARM: dts: r8a7793: Adjust SMP routine size
> > 70b3ab369773 ARM: dts: r8a7794: Adjust SMP routine size
> >
> > ebf26cf1b1de ARM: dts: r8a7743: Add watchdog support to SoC dtsi
> > 5a4566ab3777 ARM: dts: r8a7745: Add watchdog support to SoC dtsi
> > acd58e2bb1e5 ARM: dts: r8a7790: Add watchdog support to SoC dtsi
> > e3f89168e72f ARM: dts: r8a7791: Add watchdog support to SoC dtsi
> > e76a6a69a1fc ARM: dts: r8a7794: Add watchdog support to SoC dtsi
> > 242cc1ab7f7c ARM: dts: iwg20m: Add watchdog support to SoM dtsi
> > 748ed07f6c7c ARM: dts: iwg22m: Add watchdog support to SoM dtsi
> >
> >
> > Dropped from "[PATCH/RFC 00/11] ARM: dts: rcar-gen2: Enable watchdog support":
> >
> > c257202482e2 ARM: dts: r8a7792: Add RWDT node
> > 01ec04dec8eb ARM: dts: r8a7793: Add RWDT node
> > 8e6ebe4f2f94 ARM: dts: lager: Enable watchdog support
> > f223ad0198f6 ARM: dts: koelsch: Enable watchdog support
> > 1d14d2bb700d ARM: dts: porter: Enable watchdog support
> > bf71652fc955 ARM: dts: blanche: Enable watchdog support
> > 13a0b10aeea4 ARM: dts: wheat: Enable watchdog support
> > 4e247bf110b8 ARM: dts: gose: Enable watchdog support
> > 2dcbd24bbf5e ARM: dts: alt: Enable watchdog support
> > 7f6844c900b4 ARM: dts: silk: Enable watchdog support
> >
> > And applied:
> >
> > [v5] ARM: shmobile: rcar-gen2: Add watchdog support
> > [v5] ARM: shmobile: Add watchdog support
> >
> > In the case of the last patch above I removed the #ifdef from the header file.
> 
> I guess the time is ripe to apply the DTS patches again, in the following order:
>   1. SMP routine size adjustments,
>   2. Watchdog support additions to dtsi,
>   3. Watchdog enablement for dts?
> 
> Thanks!

Thanks, I have tentatively reapplied all of the above.

Re: [PATCH v5 14/26] ARM: shmobile: defconfig: Enable RENESAS_WDT_GEN

[Simon Horman]

On Mon, Feb 12, 2018 at 05:44:23PM +0000, Fabrizio Castro wrote:
> R-Car Gen2 and RZ/G1 platforms come with a watchdog IP, therefore enable
> its driver by default.
> 
> Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
> Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
> Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Thanks, applied.