[PATCH v3 09/18] soc: qcom: Add qcom's pstore minidump driver support

From: Mukesh Ojha
Date: Wed May 03 2023 - 13:06:45 EST


This driver was inspired from the fact pstore ram region should be
fixed and boot firmware need to have awarness about this region,
so that it will be persistent across boot. But, there are many
QCOM SoC which does not support warm boot from hardware but they
have minidump support from the software, and for them, there is
no need of this pstore ram region to be fixed, but at the same
time have interest in the pstore frontends. So, this driver
get the dynamic reserved region from the ram and register the
ramoops platform device.

+---------+ +---------+ +--------+ +---------+
| console | | pmsg | | ftrace | | dmesg |
+---------+ +---------+ +--------+ +---------+
| | | |
| | | |
+------------------------------------------+
|
\ /
+----------------+
(1) |pstore frontends|
+----------------+
|
\ /
+------------------- +
(2) | pstore backend(ram)|
+--------------------+
|
\ /
+--------------------+
(3) |qcom_pstore_minidump|
+--------------------+
|
\ /
+---------------+
(4) | qcom_minidump |
+---------------+

This driver will route all the pstore front data to the stored
in qcom pstore reserved region and the reason of showing an
arrow from (3) to (4) as qcom_pstore_minidump driver will register
all the available frontends region with qcom minidump driver
in upcoming patch.

Signed-off-by: Mukesh Ojha <quic_mojha@xxxxxxxxxxx>
---
drivers/soc/qcom/Kconfig | 11 +++
drivers/soc/qcom/Makefile | 1 +
drivers/soc/qcom/qcom_pstore_minidump.c | 116 ++++++++++++++++++++++++++++++++
3 files changed, 128 insertions(+)
create mode 100644 drivers/soc/qcom/qcom_pstore_minidump.c

diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index 15c931e..afdc634 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -293,4 +293,15 @@ config QCOM_MINIDUMP
these selective regions will be dumped instead of the entire DDR.
This saves significant amount of time and/or storage space.

+config QCOM_PSTORE_MINIDUMP
+ tristate "Pstore support for QCOM Minidump"
+ depends on ARCH_QCOM
+ depends on PSTORE_RAM
+ depends on QCOM_MINIDUMP
+ help
+ Enablement of this driver ensures that ramoops region can be anywhere
+ reserved in ram instead of being fixed address which needs boot firmware
+ awareness. So, this driver creates plaform device and registers available
+ frontend region with the Qualcomm's minidump driver.
+
endmenu
diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index 1ebe081..02d30d7 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -34,3 +34,4 @@ obj-$(CONFIG_QCOM_KRYO_L2_ACCESSORS) += kryo-l2-accessors.o
obj-$(CONFIG_QCOM_ICC_BWMON) += icc-bwmon.o
obj-$(CONFIG_QCOM_INLINE_CRYPTO_ENGINE) += ice.o
obj-$(CONFIG_QCOM_MINIDUMP) += qcom_minidump.o
+obj-$(CONFIG_QCOM_PSTORE_MINIDUMP) += qcom_pstore_minidump.o
diff --git a/drivers/soc/qcom/qcom_pstore_minidump.c b/drivers/soc/qcom/qcom_pstore_minidump.c
new file mode 100644
index 0000000..8d58500
--- /dev/null
+++ b/drivers/soc/qcom/qcom_pstore_minidump.c
@@ -0,0 +1,116 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/*
+ * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/platform_device.h>
+#include <linux/pstore_ram.h>
+#include <soc/qcom/qcom_minidump.h>
+
+struct qcom_ramoops_config {
+ unsigned long record_size;
+ unsigned long console_size;
+ unsigned long ftrace_size;
+ unsigned long pmsg_size;
+ unsigned int mem_type;
+ unsigned int flags;
+ int max_reason;
+};
+
+struct qcom_ramoops_dd {
+ struct ramoops_platform_data qcom_ramoops_pdata;
+ struct platform_device *ramoops_pdev;
+};
+
+static struct qcom_ramoops_config default_ramoops_config = {
+ .mem_type = 2,
+ .record_size = 0x0,
+ .console_size = 0x200000,
+ .ftrace_size = 0x0,
+ .pmsg_size = 0x0,
+};
+
+static struct qcom_ramoops_dd *qcom_rdd;
+static int qcom_ramoops_probe(struct platform_device *pdev)
+{
+ struct device_node *of_node = pdev->dev.of_node;
+ struct device_node *node;
+ const struct qcom_ramoops_config *cfg;
+ struct ramoops_platform_data *pdata;
+ struct reserved_mem *rmem;
+ long ret;
+
+ node = of_parse_phandle(of_node, "memory-region", 0);
+ if (!node)
+ return -ENODEV;
+
+ rmem = of_reserved_mem_lookup(node);
+ of_node_put(node);
+ if (!rmem) {
+ dev_err(&pdev->dev, "failed to locate DT /reserved-memory resource\n");
+ return -EINVAL;
+ }
+
+ qcom_rdd = devm_kzalloc(&pdev->dev, sizeof(*qcom_rdd), GFP_KERNEL);
+ if (!qcom_rdd)
+ return -ENOMEM;
+
+ cfg = of_device_get_match_data(&pdev->dev);
+ if (!cfg) {
+ dev_err(&pdev->dev, "failed to get supported matched data\n");
+ return -ENOENT;
+ }
+
+ pdata = &qcom_rdd->qcom_ramoops_pdata;
+ pdata->mem_size = rmem->size;
+ pdata->mem_address = rmem->base;
+ pdata->mem_type = cfg->mem_type;
+ pdata->record_size = cfg->record_size;
+ pdata->console_size = cfg->console_size;
+ pdata->ftrace_size = cfg->ftrace_size;
+ pdata->pmsg_size = cfg->pmsg_size;
+ pdata->max_reason = KMSG_DUMP_PANIC;
+
+ qcom_rdd->ramoops_pdev = platform_device_register_data(NULL, "ramoops", -1,
+ pdata, sizeof(*pdata));
+ if (IS_ERR(qcom_rdd->ramoops_pdev)) {
+ ret = PTR_ERR(qcom_rdd->ramoops_pdev);
+ dev_err(&pdev->dev, "could not create platform device: %ld\n", ret);
+ qcom_rdd->ramoops_pdev = NULL;
+ }
+
+ return ret;
+}
+
+static int qcom_ramoops_remove(struct platform_device *pdev)
+{
+ platform_device_unregister(qcom_rdd->ramoops_pdev);
+ qcom_rdd->ramoops_pdev = NULL;
+
+ return 0;
+}
+
+static const struct of_device_id qcom_ramoops_of_match[] = {
+ { .compatible = "qcom,sm8450-ramoops-minidump", .data = &default_ramoops_config },
+ { .compatible = "qcom,ramoops-minidump", .data = &default_ramoops_config },
+ {}
+};
+
+MODULE_DEVICE_TABLE(of, qcom_ramoops_of_match);
+static struct platform_driver qcom_ramoops_drv = {
+ .driver = {
+ .name = "qcom,ramoops-minidump",
+ .of_match_table = qcom_ramoops_of_match,
+ },
+ .probe = qcom_ramoops_probe,
+ .remove = qcom_ramoops_remove,
+};
+
+module_platform_driver(qcom_ramoops_drv);
+
+MODULE_DESCRIPTION("Qualcomm minidump pstore driver");
+MODULE_LICENSE("GPL");
--
2.7.4