[PATCH v2 0/2] ACPI: Arm Generic Diagnostic Dump and Reset device

[PATCH v2 0/2] ACPI: Arm Generic Diagnostic Dump and Reset device

[Ilkka Koskinen]

Arm Generic Diagnostic Dump and Reset device enables a maintainer to
request OS to perform a diagnostic dump and reset a system via SDEI
event or an interrupt. This patchset adds support for the SDEI path.

I do have a patch to enable the interrupt path as well but I'm holding
it back since AGDI table is missing interrupt configuration fields
(trigger type etc.).

The recently published specification is available at
https://developer.arm.com/documentation/den0093/latest

The patchset was tested on Ampere Altra/Mt. Jade.

The patchset applies on top of
  git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm master
  git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-next/core


It seems that the correct order to upstream ACPICA patch first and backport
it to kernel. Thus, I'm assuming this patchset should not get merged yet.

From v1:
     * Moved pdata to the stack and dropped unnecessary kzalloc() in agdi_init()
     * Changed the ACPICA patch upstreaming order comment in the paragraph above

Ilkka Koskinen (2):
  ACPI: AGDI: Add AGDI tables to drivers/acpi
  ACPI: AGDI: Add driver for Arm Generic Diagnostic Dump and Reset
    device

 drivers/acpi/arm64/Kconfig  |   8 +++
 drivers/acpi/arm64/Makefile |   1 +
 drivers/acpi/arm64/agdi.c   | 125 ++++++++++++++++++++++++++++++++++++
 drivers/acpi/tables.c       |   2 +-
 include/acpi/actbl2.h       |  20 ++++++
 5 files changed, 155 insertions(+), 1 deletion(-)
 create mode 100644 drivers/acpi/arm64/agdi.c

-- 
2.17.1

[PATCH v2 1/2] ACPI: AGDI: Add AGDI tables to drivers/acpi

[Ilkka Koskinen]

ACPI for Arm Components 1.1 Platform Design Document v1.1 [0] specifices
Arm Generic Diagnostic Device Interface (AGDI). It allows an admin to
issue diagnostic dump and reset via an SDEI event or an interrupt. This
patch adds support to ACPI/AGDI tables.

[0] https://developer.arm.com/documentation/den0093/latest/

Signed-off-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>
---
 drivers/acpi/tables.c |  2 +-
 include/acpi/actbl2.h | 20 ++++++++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c
index 71419eb16e09..5e3169bcb9fb 100644
--- a/drivers/acpi/tables.c
+++ b/drivers/acpi/tables.c
@@ -500,7 +500,7 @@ static const char table_sigs[][ACPI_NAMESEG_SIZE] __initconst = {
 	ACPI_SIG_WDDT, ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT,
 	ACPI_SIG_PSDT, ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT,
 	ACPI_SIG_IORT, ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT,
-	ACPI_SIG_NHLT };
+	ACPI_SIG_NHLT, ACPI_SIG_AGDI };
 
 #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
 
diff --git a/include/acpi/actbl2.h b/include/acpi/actbl2.h
index 71ca090fd61b..66ca85b9f5fe 100644
--- a/include/acpi/actbl2.h
+++ b/include/acpi/actbl2.h
@@ -24,6 +24,7 @@
  * file. Useful because they make it more difficult to inadvertently type in
  * the wrong signature.
  */
+#define ACPI_SIG_AGDI           "AGDI"	/* ARM Generic Diagnostic Dump and Reset Device Interface */
 #define ACPI_SIG_BDAT           "BDAT"	/* BIOS Data ACPI Table */
 #define ACPI_SIG_IORT           "IORT"	/* IO Remapping Table */
 #define ACPI_SIG_IVRS           "IVRS"	/* I/O Virtualization Reporting Structure */
@@ -237,6 +238,25 @@ typedef struct acpi_aest_node_interrupt {
 #define ACPI_AEST_NODE_ERROR_RECOVERY       1
 #define ACPI_AEST_XRUPT_RESERVED            2	/* 2 and above are reserved */
 
+/*******************************************************************************
+ * AGDI - Generic Diagnostic Dump and Reset Device Interface
+ *
+ * Document number: ARM DEN0093
+ *
+ *******************************************************************************/
+
+struct acpi_table_agdi {
+	struct acpi_table_header header;
+	u8 flags;
+	u8 reserved[3];
+	u32 sdei_event;
+	u32 gsiv;
+};
+
+/* Masks for Flags field above for AGDI table */
+
+#define ACPI_AGDI_SIGNALING_MODE (1)
+
 /*******************************************************************************
  *
  * BDAT - BIOS Data ACPI Table
-- 
2.17.1

[PATCH v2 2/2] ACPI: AGDI: Add driver for Arm Generic Diagnostic Dump and Reset device

[Ilkka Koskinen]

ACPI for Arm Components 1.1 Platform Design Document v1.1 [0] specifices
Arm Generic Diagnostic Device Interface (AGDI). It allows an admin to
issue diagnostic dump and reset via an SDEI event or an interrupt.
This patch implements SDEI path.

[0] https://developer.arm.com/documentation/den0093/latest/

Signed-off-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>
---
 drivers/acpi/arm64/Kconfig  |   8 +++
 drivers/acpi/arm64/Makefile |   1 +
 drivers/acpi/arm64/agdi.c   | 125 ++++++++++++++++++++++++++++++++++++
 3 files changed, 134 insertions(+)
 create mode 100644 drivers/acpi/arm64/agdi.c

diff --git a/drivers/acpi/arm64/Kconfig b/drivers/acpi/arm64/Kconfig
index 6dba187f4f2e..24869ba5b365 100644
--- a/drivers/acpi/arm64/Kconfig
+++ b/drivers/acpi/arm64/Kconfig
@@ -8,3 +8,11 @@ config ACPI_IORT
 
 config ACPI_GTDT
 	bool
+
+config ACPI_AGDI
+	bool "Arm Generic Diagnostic Dump and Reset Device Interface"
+	depends on ARM_SDE_INTERFACE
+	help
+	  Arm Generic Diagnostic Dump and Reset Device Interface (AGDI) is
+	  a standard that enables issuing a non-maskable diagnostic dump and
+	  reset command.
diff --git a/drivers/acpi/arm64/Makefile b/drivers/acpi/arm64/Makefile
index 66acbe77f46e..7b9e4045659d 100644
--- a/drivers/acpi/arm64/Makefile
+++ b/drivers/acpi/arm64/Makefile
@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_ACPI_AGDI) 	+= agdi.o
 obj-$(CONFIG_ACPI_IORT) 	+= iort.o
 obj-$(CONFIG_ACPI_GTDT) 	+= gtdt.o
 obj-y				+= dma.o
diff --git a/drivers/acpi/arm64/agdi.c b/drivers/acpi/arm64/agdi.c
new file mode 100644
index 000000000000..6525ccbae5c1
--- /dev/null
+++ b/drivers/acpi/arm64/agdi.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * This file implements handling of
+ * Arm Generic Diagnostic Dump and Reset Interface table (AGDI)
+ *
+ * Copyright (c) 2021, Ampere Computing LLC
+ */
+
+#define pr_fmt(fmt) "ACPI: AGDI: " fmt
+
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/acpi.h>
+#include <linux/arm_sdei.h>
+#include <linux/io.h>
+
+struct agdi_data {
+	int sdei_event;
+};
+
+static int agdi_sdei_handler(u32 sdei_event, struct pt_regs *regs, void *arg)
+{
+	nmi_panic(regs, "Arm Generic Diagnostic Dump and Reset SDEI event issued");
+	return 0;
+}
+
+static int agdi_sdei_probe(struct platform_device *pdev,
+			   struct agdi_data *adata)
+{
+	int err;
+
+	err = sdei_event_register(adata->sdei_event, agdi_sdei_handler, pdev);
+	if (err) {
+		dev_err(&pdev->dev, "Failed to register for SDEI event %d",
+			adata->sdei_event);
+		return err;
+	}
+
+	err = sdei_event_enable(adata->sdei_event);
+	if (err)  {
+		sdei_event_unregister(adata->sdei_event);
+		dev_err(&pdev->dev, "Failed to enable event %d\n",
+			adata->sdei_event);
+		return err;
+	}
+
+	return 0;
+}
+
+static int agdi_probe(struct platform_device *pdev)
+{
+	struct agdi_data *adata;
+
+	adata = dev_get_platdata(&pdev->dev);
+	if (!adata)
+		return -EINVAL;
+
+	return agdi_sdei_probe(pdev, adata);
+}
+
+static int agdi_remove(struct platform_device *pdev)
+{
+	struct agdi_data *adata = platform_get_drvdata(pdev);
+
+	sdei_event_disable(adata->sdei_event);
+	sdei_event_unregister(adata->sdei_event);
+
+	return 0;
+}
+
+static struct platform_driver agdi_driver = {
+	.driver = {
+		.name = "agdi",
+	},
+	.probe = agdi_probe,
+	.remove = agdi_remove,
+};
+
+static int __init agdi_init(void)
+{
+	int ret;
+	acpi_status status;
+	struct acpi_table_agdi *agdi_table;
+	struct agdi_data pdata;
+	struct platform_device *pdev;
+
+	if (acpi_disabled)
+		return 0;
+
+	status = acpi_get_table(ACPI_SIG_AGDI, 0,
+				(struct acpi_table_header **) &agdi_table);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	if (agdi_table->flags & ACPI_AGDI_SIGNALING_MODE) {
+		pr_warn("Interrupt signaling is not supported");
+		ret = -ENODEV;
+		goto err_put_table;
+	}
+
+	pdata.sdei_event = agdi_table->sdei_event;
+
+	pdev = platform_device_register_data(NULL, "agdi", 0, &pdata, sizeof(pdata));
+	if (IS_ERR(pdev)) {
+		ret = PTR_ERR(pdev);
+		goto err_put_table;
+	}
+
+	ret = platform_driver_register(&agdi_driver);
+	if (ret)
+		goto err_device_unregister;
+
+	acpi_put_table((struct acpi_table_header *)agdi_table);
+	return 0;
+
+err_device_unregister:
+	platform_device_unregister(pdev);
+err_put_table:
+	acpi_put_table((struct acpi_table_header *)agdi_table);
+	return ret;
+}
+device_initcall(agdi_init);
-- 
2.17.1

Re: [PATCH v2 1/2] ACPI: AGDI: Add AGDI tables to drivers/acpi

[Rafael J. Wysocki]

On Tue, Dec 14, 2021 at 5:41 AM Ilkka Koskinen
<ilkka@os.amperecomputing.com> wrote:
>
> ACPI for Arm Components 1.1 Platform Design Document v1.1 [0] specifices
> Arm Generic Diagnostic Device Interface (AGDI). It allows an admin to
> issue diagnostic dump and reset via an SDEI event or an interrupt. This
> patch adds support to ACPI/AGDI tables.
>
> [0] https://developer.arm.com/documentation/den0093/latest/
>
> Signed-off-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>
> ---
>  drivers/acpi/tables.c |  2 +-
>  include/acpi/actbl2.h | 20 ++++++++++++++++++++
>  2 files changed, 21 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c
> index 71419eb16e09..5e3169bcb9fb 100644
> --- a/drivers/acpi/tables.c
> +++ b/drivers/acpi/tables.c
> @@ -500,7 +500,7 @@ static const char table_sigs[][ACPI_NAMESEG_SIZE] __initconst = {
>         ACPI_SIG_WDDT, ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT,
>         ACPI_SIG_PSDT, ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT,
>         ACPI_SIG_IORT, ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT,
> -       ACPI_SIG_NHLT };
> +       ACPI_SIG_NHLT, ACPI_SIG_AGDI };
>
>  #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
>
> diff --git a/include/acpi/actbl2.h b/include/acpi/actbl2.h
> index 71ca090fd61b..66ca85b9f5fe 100644
> --- a/include/acpi/actbl2.h
> +++ b/include/acpi/actbl2.h

The changes in actbl2.h are ACPICA material and so they need to be
routed through the upstream ACPICA project.

Moreover, you have already submitted a pull request with them to the
upstream: https://github.com/acpica/acpica/pull/737/commits/cf36a6d658ca5aa8c329c2edfc3322c095ffd844

Please wait until this gets integrated and repost the rest of the
patches as incremental changes on top of that.

Re: [PATCH v2 1/2] ACPI: AGDI: Add AGDI tables to drivers/acpi

[Ilkka Koskinen]

On Wed, 15 Dec 2021, Rafael J. Wysocki wrote:

> On Tue, Dec 14, 2021 at 5:41 AM Ilkka Koskinen
> <ilkka@os.amperecomputing.com> wrote:
>>
>> ACPI for Arm Components 1.1 Platform Design Document v1.1 [0] specifices
>> Arm Generic Diagnostic Device Interface (AGDI). It allows an admin to
>> issue diagnostic dump and reset via an SDEI event or an interrupt. This
>> patch adds support to ACPI/AGDI tables.
>>
>> [0] https://developer.arm.com/documentation/den0093/latest/
>>
>> Signed-off-by: Ilkka Koskinen <ilkka@os.amperecomputing.com>
>> ---
>>  drivers/acpi/tables.c |  2 +-
>>  include/acpi/actbl2.h | 20 ++++++++++++++++++++
>>  2 files changed, 21 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c
>> index 71419eb16e09..5e3169bcb9fb 100644
>> --- a/drivers/acpi/tables.c
>> +++ b/drivers/acpi/tables.c
>> @@ -500,7 +500,7 @@ static const char table_sigs[][ACPI_NAMESEG_SIZE] __initconst = {
>>         ACPI_SIG_WDDT, ACPI_SIG_WDRT, ACPI_SIG_DSDT, ACPI_SIG_FADT,
>>         ACPI_SIG_PSDT, ACPI_SIG_RSDT, ACPI_SIG_XSDT, ACPI_SIG_SSDT,
>>         ACPI_SIG_IORT, ACPI_SIG_NFIT, ACPI_SIG_HMAT, ACPI_SIG_PPTT,
>> -       ACPI_SIG_NHLT };
>> +       ACPI_SIG_NHLT, ACPI_SIG_AGDI };
>>
>>  #define ACPI_HEADER_SIZE sizeof(struct acpi_table_header)
>>
>> diff --git a/include/acpi/actbl2.h b/include/acpi/actbl2.h
>> index 71ca090fd61b..66ca85b9f5fe 100644
>> --- a/include/acpi/actbl2.h
>> +++ b/include/acpi/actbl2.h
>
> The changes in actbl2.h are ACPICA material and so they need to be
> routed through the upstream ACPICA project.
>
> Moreover, you have already submitted a pull request with them to the
> upstream: https://github.com/acpica/acpica/pull/737/commits/cf36a6d658ca5aa8c329c2edfc3322c095ffd844
>
> Please wait until this gets integrated and repost the rest of the
> patches as incremental changes on top of that.

Thanks for clarifying the process, that makes sense to me. I'll wait until
the patch gets merged into the kernel and submit what's left from the
patchset as v3 then.

Thanks,
Ilkka