remoteproc updates for v4.17

This adds support for generating coredumps for remoteprocs using
 devcoredump, adds the Qualcomm sysmon driver for intra-remoteproc crash
 handling and a number of fixes in Qualcomm and IMX drivers.
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Merge tag 'rproc-v4.17' of git://github.com/andersson/remoteproc

Pull remoteproc updates from Bjorn Andersson:

 - add support for generating coredumps for remoteprocs using
   devcoredump

 - add the Qualcomm sysmon driver for intra-remoteproc crash handling

 - a number of fixes in Qualcomm and IMX drivers

* tag 'rproc-v4.17' of git://github.com/andersson/remoteproc:
  remoteproc: fix null pointer dereference on glink only platforms
  soc: qcom: qmi: add CONFIG_NET dependency
  remoteproc: imx_rproc: Slightly simplify code in 'imx_rproc_probe()'
  remoteproc: imx_rproc: Re-use existing error handling path in 'imx_rproc_probe()'
  remoteproc: imx_rproc: Fix an error handling path in 'imx_rproc_probe()'
  samples: Introduce Qualcomm QMI sample client
  remoteproc: qcom: Introduce sysmon
  remoteproc: Pass type of shutdown to subdev remove
  remoteproc: qcom: Register segments for core dump
  soc: qcom: mdt-loader: Return relocation base
  remoteproc: Rename "load_rsc_table" to "parse_fw"
  remoteproc: Add remote processor coredump support
  remoteproc: Remove null character write of shared mem

drivers/gpu/drm/msm/adreno/a5xx_gpu.c

@@ -89,14 +89,14 @@ static int zap_shader_load_mdt(struct msm_gpu *gpu, const char *fwname)
 	 */
 	if (to_adreno_gpu(gpu)->fwloc == FW_LOCATION_LEGACY) {
 		ret = qcom_mdt_load(dev, fw, fwname, GPU_PAS_ID,
-				mem_region, mem_phys, mem_size);
+				mem_region, mem_phys, mem_size, NULL);
 	} else {
 		char newname[strlen("qcom/") + strlen(fwname) + 1];
 
 		sprintf(newname, "qcom/%s", fwname);
 
 		ret = qcom_mdt_load(dev, fw, newname, GPU_PAS_ID,
-				mem_region, mem_phys, mem_size);
+				mem_region, mem_phys, mem_size, NULL);
 	}
 	if (ret)
 		goto out;

drivers/media/platform/qcom/venus/firmware.c

@@ -76,7 +76,7 @@ int venus_boot(struct device *dev, const char *fwname)
 	}
 
 	ret = qcom_mdt_load(dev, mdt, fwname, VENUS_PAS_ID, mem_va, mem_phys,
-			    mem_size);
+			    mem_size, NULL);
 
 	release_firmware(mdt);
 

drivers/remoteproc/Kconfig

@@ -6,6 +6,7 @@ config REMOTEPROC
 	select CRC32
 	select FW_LOADER
 	select VIRTIO
+	select WANT_DEV_COREDUMP
 	help
 	  Support for remote processors (such as DSP coprocessors). These
 	  are mainly used on embedded systems.
@@ -90,6 +91,7 @@ config QCOM_ADSP_PIL
 	depends on QCOM_SMEM
 	depends on RPMSG_QCOM_SMD || (COMPILE_TEST && RPMSG_QCOM_SMD=n)
 	depends on RPMSG_QCOM_GLINK_SMEM || RPMSG_QCOM_GLINK_SMEM=n
+	depends on QCOM_SYSMON || QCOM_SYSMON=n
 	select MFD_SYSCON
 	select QCOM_MDT_LOADER
 	select QCOM_RPROC_COMMON
@@ -107,6 +109,7 @@ config QCOM_Q6V5_PIL
 	depends on QCOM_SMEM
 	depends on RPMSG_QCOM_SMD || (COMPILE_TEST && RPMSG_QCOM_SMD=n)
 	depends on RPMSG_QCOM_GLINK_SMEM || RPMSG_QCOM_GLINK_SMEM=n
+	depends on QCOM_SYSMON || QCOM_SYSMON=n
 	select MFD_SYSCON
 	select QCOM_RPROC_COMMON
 	select QCOM_SCM
@@ -114,12 +117,28 @@ config QCOM_Q6V5_PIL
 	  Say y here to support the Qualcomm Peripherial Image Loader for the
 	  Hexagon V5 based remote processors.
 
+config QCOM_SYSMON
+	tristate "Qualcomm sysmon driver"
+	depends on RPMSG
+	depends on ARCH_QCOM
+	depends on NET
+	select QCOM_QMI_HELPERS
+	help
+	  The sysmon driver implements a sysmon QMI client and a handler for
+	  the sys_mon SMD and GLINK channel, which are used for graceful
+	  shutdown, retrieving failure information and propagating information
+	  about other subsystems being shut down.
+
+	  Say y here if your system runs firmware on any other subsystems, e.g.
+	  modem or DSP.
+
 config QCOM_WCNSS_PIL
 	tristate "Qualcomm WCNSS Peripheral Image Loader"
 	depends on OF && ARCH_QCOM
 	depends on RPMSG_QCOM_SMD || (COMPILE_TEST && RPMSG_QCOM_SMD=n)
 	depends on RPMSG_QCOM_GLINK_SMEM || RPMSG_QCOM_GLINK_SMEM=n
 	depends on QCOM_SMEM
+	depends on QCOM_SYSMON || QCOM_SYSMON=n
 	select QCOM_MDT_LOADER
 	select QCOM_RPROC_COMMON
 	select QCOM_SCM

drivers/remoteproc/Makefile

@@ -17,6 +17,7 @@ obj-$(CONFIG_KEYSTONE_REMOTEPROC)	+= keystone_remoteproc.o
 obj-$(CONFIG_QCOM_ADSP_PIL)		+= qcom_adsp_pil.o
 obj-$(CONFIG_QCOM_RPROC_COMMON)		+= qcom_common.o
 obj-$(CONFIG_QCOM_Q6V5_PIL)		+= qcom_q6v5_pil.o
+obj-$(CONFIG_QCOM_SYSMON)		+= qcom_sysmon.o
 obj-$(CONFIG_QCOM_WCNSS_PIL)		+= qcom_wcnss_pil.o
 qcom_wcnss_pil-y			+= qcom_wcnss.o
 qcom_wcnss_pil-y			+= qcom_wcnss_iris.o

drivers/remoteproc/imx_rproc.c

@@ -333,14 +333,14 @@ static int imx_rproc_probe(struct platform_device *pdev)
 	/* set some other name then imx */
 	rproc = rproc_alloc(dev, "imx-rproc", &imx_rproc_ops,
 			    NULL, sizeof(*priv));
-	if (!rproc) {
+	if (!rproc)
-		ret = -ENOMEM;
+		return -ENOMEM;
-		goto err;
-	}
 
 	dcfg = of_device_get_match_data(dev);
-	if (!dcfg)
+	if (!dcfg) {
-		return -EINVAL;
+		ret = -EINVAL;
+		goto err_put_rproc;
+	}
 
 	priv = rproc->priv;
 	priv->rproc = rproc;
@@ -359,8 +359,8 @@ static int imx_rproc_probe(struct platform_device *pdev)
 	priv->clk = devm_clk_get(dev, NULL);
 	if (IS_ERR(priv->clk)) {
 		dev_err(dev, "Failed to get clock\n");
-		rproc_free(rproc);
+		ret = PTR_ERR(priv->clk);
-		return PTR_ERR(priv->clk);
+		goto err_put_rproc;
 	}
 
 	/*
@@ -370,8 +370,7 @@ static int imx_rproc_probe(struct platform_device *pdev)
 	ret = clk_prepare_enable(priv->clk);
 	if (ret) {
 		dev_err(&rproc->dev, "Failed to enable clock\n");
-		rproc_free(rproc);
+		goto err_put_rproc;
-		return ret;
 	}
 
 	ret = rproc_add(rproc);
@@ -380,13 +379,13 @@ static int imx_rproc_probe(struct platform_device *pdev)
 		goto err_put_clk;
 	}
 
-	return ret;
+	return 0;
 
 err_put_clk:
 	clk_disable_unprepare(priv->clk);
 err_put_rproc:
 	rproc_free(rproc);
-err:
+
 	return ret;
 }
 

drivers/remoteproc/qcom_adsp_pil.c

@@ -38,7 +38,10 @@ struct adsp_data {
 	const char *firmware_name;
 	int pas_id;
 	bool has_aggre2_clk;
+
 	const char *ssr_name;
+	const char *sysmon_name;
+	int ssctl_id;
 };
 
 struct qcom_adsp {
@@ -75,6 +78,7 @@ struct qcom_adsp {
 	struct qcom_rproc_glink glink_subdev;
 	struct qcom_rproc_subdev smd_subdev;
 	struct qcom_rproc_ssr ssr_subdev;
+	struct qcom_sysmon *sysmon;
 };
 
 static int adsp_load(struct rproc *rproc, const struct firmware *fw)
@@ -82,7 +86,9 @@ static int adsp_load(struct rproc *rproc, const struct firmware *fw)
 	struct qcom_adsp *adsp = (struct qcom_adsp *)rproc->priv;
 
 	return qcom_mdt_load(adsp->dev, fw, rproc->firmware, adsp->pas_id,
-			     adsp->mem_region, adsp->mem_phys, adsp->mem_size);
+			     adsp->mem_region, adsp->mem_phys, adsp->mem_size,
+			     &adsp->mem_reloc);
+
 }
 
 static int adsp_start(struct rproc *rproc)
@@ -177,6 +183,7 @@ static const struct rproc_ops adsp_ops = {
 	.start = adsp_start,
 	.stop = adsp_stop,
 	.da_to_va = adsp_da_to_va,
+	.parse_fw = qcom_register_dump_segments,
 	.load = adsp_load,
 };
 
@@ -201,9 +208,6 @@ static irqreturn_t adsp_fatal_interrupt(int irq, void *dev)
 
 	rproc_report_crash(adsp->rproc, RPROC_FATAL_ERROR);
 
-	if (!IS_ERR(msg))
-		msg[0] = '\0';
-
 	return IRQ_HANDLED;
 }
 
@@ -398,6 +402,9 @@ static int adsp_probe(struct platform_device *pdev)
 	qcom_add_glink_subdev(rproc, &adsp->glink_subdev);
 	qcom_add_smd_subdev(rproc, &adsp->smd_subdev);
 	qcom_add_ssr_subdev(rproc, &adsp->ssr_subdev, desc->ssr_name);
+	adsp->sysmon = qcom_add_sysmon_subdev(rproc,
+					      desc->sysmon_name,
+					      desc->ssctl_id);
 
 	ret = rproc_add(rproc);
 	if (ret)
@@ -419,6 +426,7 @@ static int adsp_remove(struct platform_device *pdev)
 	rproc_del(adsp->rproc);
 
 	qcom_remove_glink_subdev(adsp->rproc, &adsp->glink_subdev);
+	qcom_remove_sysmon_subdev(adsp->sysmon);
 	qcom_remove_smd_subdev(adsp->rproc, &adsp->smd_subdev);
 	qcom_remove_ssr_subdev(adsp->rproc, &adsp->ssr_subdev);
 	rproc_free(adsp->rproc);
@@ -432,6 +440,8 @@ static const struct adsp_data adsp_resource_init = {
 		.pas_id = 1,
 		.has_aggre2_clk = false,
 		.ssr_name = "lpass",
+		.sysmon_name = "adsp",
+		.ssctl_id = 0x14,
 };
 
 static const struct adsp_data slpi_resource_init = {
@@ -440,6 +450,8 @@ static const struct adsp_data slpi_resource_init = {
 		.pas_id = 12,
 		.has_aggre2_clk = true,
 		.ssr_name = "dsps",
+		.sysmon_name = "slpi",
+		.ssctl_id = 0x16,
 };
 
 static const struct of_device_id adsp_of_match[] = {

drivers/remoteproc/qcom_common.c

@@ -22,6 +22,7 @@
 #include <linux/remoteproc.h>
 #include <linux/rpmsg/qcom_glink.h>
 #include <linux/rpmsg/qcom_smd.h>
+#include <linux/soc/qcom/mdt_loader.h>
 
 #include "remoteproc_internal.h"
 #include "qcom_common.h"
@@ -41,7 +42,7 @@ static int glink_subdev_probe(struct rproc_subdev *subdev)
 	return PTR_ERR_OR_ZERO(glink->edge);
 }
 
-static void glink_subdev_remove(struct rproc_subdev *subdev)
+static void glink_subdev_remove(struct rproc_subdev *subdev, bool crashed)
 {
 	struct qcom_rproc_glink *glink = to_glink_subdev(subdev);
 
@@ -74,11 +75,57 @@ EXPORT_SYMBOL_GPL(qcom_add_glink_subdev);
  */
 void qcom_remove_glink_subdev(struct rproc *rproc, struct qcom_rproc_glink *glink)
 {
+	if (!glink->node)
+		return;
+
 	rproc_remove_subdev(rproc, &glink->subdev);
 	of_node_put(glink->node);
 }
 EXPORT_SYMBOL_GPL(qcom_remove_glink_subdev);
 
+/**
+ * qcom_register_dump_segments() - register segments for coredump
+ * @rproc:	remoteproc handle
+ * @fw:		firmware header
+ *
+ * Register all segments of the ELF in the remoteproc coredump segment list
+ *
+ * Return: 0 on success, negative errno on failure.
+ */
+int qcom_register_dump_segments(struct rproc *rproc,
+				const struct firmware *fw)
+{
+	const struct elf32_phdr *phdrs;
+	const struct elf32_phdr *phdr;
+	const struct elf32_hdr *ehdr;
+	int ret;
+	int i;
+
+	ehdr = (struct elf32_hdr *)fw->data;
+	phdrs = (struct elf32_phdr *)(ehdr + 1);
+
+	for (i = 0; i < ehdr->e_phnum; i++) {
+		phdr = &phdrs[i];
+
+		if (phdr->p_type != PT_LOAD)
+			continue;
+
+		if ((phdr->p_flags & QCOM_MDT_TYPE_MASK) == QCOM_MDT_TYPE_HASH)
+			continue;
+
+		if (!phdr->p_memsz)
+			continue;
+
+		ret = rproc_coredump_add_segment(rproc, phdr->p_paddr,
+						 phdr->p_memsz);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(qcom_register_dump_segments);
+
 static int smd_subdev_probe(struct rproc_subdev *subdev)
 {
 	struct qcom_rproc_subdev *smd = to_smd_subdev(subdev);
@@ -88,7 +135,7 @@ static int smd_subdev_probe(struct rproc_subdev *subdev)
 	return PTR_ERR_OR_ZERO(smd->edge);
 }
 
-static void smd_subdev_remove(struct rproc_subdev *subdev)
+static void smd_subdev_remove(struct rproc_subdev *subdev, bool crashed)
 {
 	struct qcom_rproc_subdev *smd = to_smd_subdev(subdev);
 
@@ -121,6 +168,9 @@ EXPORT_SYMBOL_GPL(qcom_add_smd_subdev);
  */
 void qcom_remove_smd_subdev(struct rproc *rproc, struct qcom_rproc_subdev *smd)
 {
+	if (!smd->node)
+		return;
+
 	rproc_remove_subdev(rproc, &smd->subdev);
 	of_node_put(smd->node);
 }
@@ -157,7 +207,7 @@ static int ssr_notify_start(struct rproc_subdev *subdev)
 	return  0;
 }
 
-static void ssr_notify_stop(struct rproc_subdev *subdev)
+static void ssr_notify_stop(struct rproc_subdev *subdev, bool crashed)
 {
 	struct qcom_rproc_ssr *ssr = to_ssr_subdev(subdev);
 

drivers/remoteproc/qcom_common.h

@@ -4,6 +4,9 @@
 
 #include <linux/remoteproc.h>
 #include "remoteproc_internal.h"
+#include <linux/soc/qcom/qmi.h>
+
+struct qcom_sysmon;
 
 struct qcom_rproc_glink {
 	struct rproc_subdev subdev;
@@ -30,6 +33,8 @@ struct qcom_rproc_ssr {
 void qcom_add_glink_subdev(struct rproc *rproc, struct qcom_rproc_glink *glink);
 void qcom_remove_glink_subdev(struct rproc *rproc, struct qcom_rproc_glink *glink);
 
+int qcom_register_dump_segments(struct rproc *rproc, const struct firmware *fw);
+
 void qcom_add_smd_subdev(struct rproc *rproc, struct qcom_rproc_subdev *smd);
 void qcom_remove_smd_subdev(struct rproc *rproc, struct qcom_rproc_subdev *smd);
 
@@ -37,4 +42,22 @@ void qcom_add_ssr_subdev(struct rproc *rproc, struct qcom_rproc_ssr *ssr,
 			 const char *ssr_name);
 void qcom_remove_ssr_subdev(struct rproc *rproc, struct qcom_rproc_ssr *ssr);
 
+#if IS_ENABLED(CONFIG_QCOM_SYSMON)
+struct qcom_sysmon *qcom_add_sysmon_subdev(struct rproc *rproc,
+					   const char *name,
+					   int ssctl_instance);
+void qcom_remove_sysmon_subdev(struct qcom_sysmon *sysmon);
+#else
+static inline struct qcom_sysmon *qcom_add_sysmon_subdev(struct rproc *rproc,
+							 const char *name,
+							 int ssctl_instance)
+{
+	return NULL;
+}
+
+static inline void qcom_remove_sysmon_subdev(struct qcom_sysmon *sysmon)
+{
+}
+#endif
+
 #endif

drivers/remoteproc/qcom_q6v5_pil.c

@@ -168,6 +168,7 @@ struct q6v5 {
 
 	struct qcom_rproc_subdev smd_subdev;
 	struct qcom_rproc_ssr ssr_subdev;
+	struct qcom_sysmon *sysmon;
 	bool need_mem_protection;
 	int mpss_perm;
 	int mba_perm;
@@ -939,9 +940,6 @@ static irqreturn_t q6v5_wdog_interrupt(int irq, void *dev)
 
 	rproc_report_crash(qproc->rproc, RPROC_WATCHDOG);
 
-	if (!IS_ERR(msg))
-		msg[0] = '\0';
-
 	return IRQ_HANDLED;
 }
 
@@ -959,9 +957,6 @@ static irqreturn_t q6v5_fatal_interrupt(int irq, void *dev)
 
 	rproc_report_crash(qproc->rproc, RPROC_FATAL_ERROR);
 
-	if (!IS_ERR(msg))
-		msg[0] = '\0';
-
 	return IRQ_HANDLED;
 }
 
@@ -1215,6 +1210,7 @@ static int q6v5_probe(struct platform_device *pdev)
 	qproc->mba_perm = BIT(QCOM_SCM_VMID_HLOS);
 	qcom_add_smd_subdev(rproc, &qproc->smd_subdev);
 	qcom_add_ssr_subdev(rproc, &qproc->ssr_subdev, "mpss");
+	qproc->sysmon = qcom_add_sysmon_subdev(rproc, "modem", 0x12);
 
 	ret = rproc_add(rproc);
 	if (ret)
@@ -1234,6 +1230,7 @@ static int q6v5_remove(struct platform_device *pdev)
 
 	rproc_del(qproc->rproc);
 
+	qcom_remove_sysmon_subdev(qproc->sysmon);
 	qcom_remove_smd_subdev(qproc->rproc, &qproc->smd_subdev);
 	qcom_remove_ssr_subdev(qproc->rproc, &qproc->ssr_subdev);
 	rproc_free(qproc->rproc);

drivers/remoteproc/qcom_sysmon.c

@@ -0,0 +1,579 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2017, Linaro Ltd.
+ */
+#include <linux/firmware.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/notifier.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/remoteproc/qcom_rproc.h>
+#include <linux/rpmsg.h>
+
+#include "qcom_common.h"
+
+static BLOCKING_NOTIFIER_HEAD(sysmon_notifiers);
+
+struct qcom_sysmon {
+	struct rproc_subdev subdev;
+	struct rproc *rproc;
+
+	struct list_head node;
+
+	const char *name;
+
+	int ssctl_version;
+	int ssctl_instance;
+
+	struct notifier_block nb;
+
+	struct device *dev;
+
+	struct rpmsg_endpoint *ept;
+	struct completion comp;
+	struct mutex lock;
+
+	bool ssr_ack;
+
+	struct qmi_handle qmi;
+	struct sockaddr_qrtr ssctl;
+};
+
+static DEFINE_MUTEX(sysmon_lock);
+static LIST_HEAD(sysmon_list);
+
+/**
+ * sysmon_send_event() - send notification of other remote's SSR event
+ * @sysmon:	sysmon context
+ * @name:	other remote's name
+ */
+static void sysmon_send_event(struct qcom_sysmon *sysmon, const char *name)
+{
+	char req[50];
+	int len;
+	int ret;
+
+	len = snprintf(req, sizeof(req), "ssr:%s:before_shutdown", name);
+	if (len >= sizeof(req))
+		return;
+
+	mutex_lock(&sysmon->lock);
+	reinit_completion(&sysmon->comp);
+	sysmon->ssr_ack = false;
+
+	ret = rpmsg_send(sysmon->ept, req, len);
+	if (ret < 0) {
+		dev_err(sysmon->dev, "failed to send sysmon event\n");
+		goto out_unlock;
+	}
+
+	ret = wait_for_completion_timeout(&sysmon->comp,
+					  msecs_to_jiffies(5000));
+	if (!ret) {
+		dev_err(sysmon->dev, "timeout waiting for sysmon ack\n");
+		goto out_unlock;
+	}
+
+	if (!sysmon->ssr_ack)
+		dev_err(sysmon->dev, "unexpected response to sysmon event\n");
+
+out_unlock:
+	mutex_unlock(&sysmon->lock);
+}
+
+/**
+ * sysmon_request_shutdown() - request graceful shutdown of remote
+ * @sysmon:	sysmon context
+ */
+static void sysmon_request_shutdown(struct qcom_sysmon *sysmon)
+{
+	char *req = "ssr:shutdown";
+	int ret;
+
+	mutex_lock(&sysmon->lock);
+	reinit_completion(&sysmon->comp);
+	sysmon->ssr_ack = false;
+
+	ret = rpmsg_send(sysmon->ept, req, strlen(req) + 1);
+	if (ret < 0) {
+		dev_err(sysmon->dev, "send sysmon shutdown request failed\n");
+		goto out_unlock;
+	}
+
+	ret = wait_for_completion_timeout(&sysmon->comp,
+					  msecs_to_jiffies(5000));
+	if (!ret) {
+		dev_err(sysmon->dev, "timeout waiting for sysmon ack\n");
+		goto out_unlock;
+	}
+
+	if (!sysmon->ssr_ack)
+		dev_err(sysmon->dev,
+			"unexpected response to sysmon shutdown request\n");
+
+out_unlock:
+	mutex_unlock(&sysmon->lock);
+}
+
+static int sysmon_callback(struct rpmsg_device *rpdev, void *data, int count,
+			   void *priv, u32 addr)
+{
+	struct qcom_sysmon *sysmon = priv;
+	const char *ssr_ack = "ssr:ack";
+	const int ssr_ack_len = strlen(ssr_ack) + 1;
+
+	if (!sysmon)
+		return -EINVAL;
+
+	if (count >= ssr_ack_len && !memcmp(data, ssr_ack, ssr_ack_len))
+		sysmon->ssr_ack = true;
+
+	complete(&sysmon->comp);
+
+	return 0;
+}
+
+#define SSCTL_SHUTDOWN_REQ		0x21
+#define SSCTL_SUBSYS_EVENT_REQ		0x23
+
+#define SSCTL_MAX_MSG_LEN		7
+
+#define SSCTL_SUBSYS_NAME_LENGTH	15
+
+enum {
+	SSCTL_SSR_EVENT_BEFORE_POWERUP,
+	SSCTL_SSR_EVENT_AFTER_POWERUP,
+	SSCTL_SSR_EVENT_BEFORE_SHUTDOWN,
+	SSCTL_SSR_EVENT_AFTER_SHUTDOWN,
+};
+
+enum {
+	SSCTL_SSR_EVENT_FORCED,
+	SSCTL_SSR_EVENT_GRACEFUL,
+};
+
+struct ssctl_shutdown_resp {
+	struct qmi_response_type_v01 resp;
+};
+
+static struct qmi_elem_info ssctl_shutdown_resp_ei[] = {
+	{
+		.data_type	= QMI_STRUCT,
+		.elem_len	= 1,
+		.elem_size	= sizeof(struct qmi_response_type_v01),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= 0x02,
+		.offset		= offsetof(struct ssctl_shutdown_resp, resp),
+		.ei_array	= qmi_response_type_v01_ei,
+	},
+	{}
+};
+
+struct ssctl_subsys_event_req {
+	u8 subsys_name_len;
+	char subsys_name[SSCTL_SUBSYS_NAME_LENGTH];
+	u32 event;
+	u8 evt_driven_valid;
+	u32 evt_driven;
+};
+
+static struct qmi_elem_info ssctl_subsys_event_req_ei[] = {
+	{
+		.data_type	= QMI_DATA_LEN,
+		.elem_len	= 1,
+		.elem_size	= sizeof(uint8_t),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= 0x01,
+		.offset		= offsetof(struct ssctl_subsys_event_req,
+					   subsys_name_len),
+		.ei_array	= NULL,
+	},
+	{
+		.data_type	= QMI_UNSIGNED_1_BYTE,
+		.elem_len	= SSCTL_SUBSYS_NAME_LENGTH,
+		.elem_size	= sizeof(char),
+		.array_type	= VAR_LEN_ARRAY,
+		.tlv_type	= 0x01,
+		.offset		= offsetof(struct ssctl_subsys_event_req,
+					   subsys_name),
+		.ei_array	= NULL,
+	},
+	{
+		.data_type	= QMI_SIGNED_4_BYTE_ENUM,
+		.elem_len	= 1,
+		.elem_size	= sizeof(uint32_t),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= 0x02,
+		.offset		= offsetof(struct ssctl_subsys_event_req,
+					   event),
+		.ei_array	= NULL,
+	},
+	{
+		.data_type	= QMI_OPT_FLAG,
+		.elem_len	= 1,
+		.elem_size	= sizeof(uint8_t),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= 0x10,
+		.offset		= offsetof(struct ssctl_subsys_event_req,
+					   evt_driven_valid),
+		.ei_array	= NULL,
+	},
+	{
+		.data_type	= QMI_SIGNED_4_BYTE_ENUM,
+		.elem_len	= 1,
+		.elem_size	= sizeof(uint32_t),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= 0x10,
+		.offset		= offsetof(struct ssctl_subsys_event_req,
+					   evt_driven),
+		.ei_array	= NULL,
+	},
+	{}
+};
+
+struct ssctl_subsys_event_resp {
+	struct qmi_response_type_v01 resp;
+};
+
+static struct qmi_elem_info ssctl_subsys_event_resp_ei[] = {
+	{
+		.data_type	= QMI_STRUCT,
+		.elem_len	= 1,
+		.elem_size	= sizeof(struct qmi_response_type_v01),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= 0x02,
+		.offset		= offsetof(struct ssctl_subsys_event_resp,
+					   resp),
+		.ei_array	= qmi_response_type_v01_ei,
+	},
+	{}
+};
+
+/**
+ * ssctl_request_shutdown() - request shutdown via SSCTL QMI service
+ * @sysmon:	sysmon context
+ */
+static void ssctl_request_shutdown(struct qcom_sysmon *sysmon)
+{
+	struct ssctl_shutdown_resp resp;
+	struct qmi_txn txn;
+	int ret;
+
+	ret = qmi_txn_init(&sysmon->qmi, &txn, ssctl_shutdown_resp_ei, &resp);
+	if (ret < 0) {
+		dev_err(sysmon->dev, "failed to allocate QMI txn\n");
+		return;
+	}
+
+	ret = qmi_send_request(&sysmon->qmi, &sysmon->ssctl, &txn,
+			       SSCTL_SHUTDOWN_REQ, 0, NULL, NULL);
+	if (ret < 0) {
+		dev_err(sysmon->dev, "failed to send shutdown request\n");
+		qmi_txn_cancel(&txn);
+		return;
+	}
+
+	ret = qmi_txn_wait(&txn, 5 * HZ);
+	if (ret < 0)
+		dev_err(sysmon->dev, "failed receiving QMI response\n");
+	else if (resp.resp.result)
+		dev_err(sysmon->dev, "shutdown request failed\n");
+	else
+		dev_dbg(sysmon->dev, "shutdown request completed\n");
+}
+
+/**
+ * ssctl_send_event() - send notification of other remote's SSR event
+ * @sysmon:	sysmon context
+ * @name:	other remote's name
+ */
+static void ssctl_send_event(struct qcom_sysmon *sysmon, const char *name)
+{
+	struct ssctl_subsys_event_resp resp;
+	struct ssctl_subsys_event_req req;
+	struct qmi_txn txn;
+	int ret;
+
+	memset(&resp, 0, sizeof(resp));
+	ret = qmi_txn_init(&sysmon->qmi, &txn, ssctl_subsys_event_resp_ei, &resp);
+	if (ret < 0) {
+		dev_err(sysmon->dev, "failed to allocate QMI txn\n");
+		return;
+	}
+
+	memset(&req, 0, sizeof(req));
+	strlcpy(req.subsys_name, name, sizeof(req.subsys_name));
+	req.subsys_name_len = strlen(req.subsys_name);
+	req.event = SSCTL_SSR_EVENT_BEFORE_SHUTDOWN;
+	req.evt_driven_valid = true;
+	req.evt_driven = SSCTL_SSR_EVENT_FORCED;
+
+	ret = qmi_send_request(&sysmon->qmi, &sysmon->ssctl, &txn,
+			       SSCTL_SUBSYS_EVENT_REQ, 40,
+			       ssctl_subsys_event_req_ei, &req);
+	if (ret < 0) {
+		dev_err(sysmon->dev, "failed to send shutdown request\n");
+		qmi_txn_cancel(&txn);
+		return;
+	}
+
+	ret = qmi_txn_wait(&txn, 5 * HZ);
+	if (ret < 0)
+		dev_err(sysmon->dev, "failed receiving QMI response\n");
+	else if (resp.resp.result)
+		dev_err(sysmon->dev, "ssr event send failed\n");
+	else
+		dev_dbg(sysmon->dev, "ssr event send completed\n");
+}
+
+/**
+ * ssctl_new_server() - QMI callback indicating a new service
+ * @qmi:	QMI handle
+ * @svc:	service information
+ *
+ * Return: 0 if we're interested in this service, -EINVAL otherwise.
+ */
+static int ssctl_new_server(struct qmi_handle *qmi, struct qmi_service *svc)
+{
+	struct qcom_sysmon *sysmon = container_of(qmi, struct qcom_sysmon, qmi);
+
+	switch (svc->version) {
+	case 1:
+		if (svc->instance != 0)
+			return -EINVAL;
+		if (strcmp(sysmon->name, "modem"))
+			return -EINVAL;
+		break;
+	case 2:
+		if (svc->instance != sysmon->ssctl_instance)
+			return -EINVAL;
+		break;
+	default:
+		return -EINVAL;
+	};
+
+	sysmon->ssctl_version = svc->version;
+
+	sysmon->ssctl.sq_family = AF_QIPCRTR;
+	sysmon->ssctl.sq_node = svc->node;
+	sysmon->ssctl.sq_port = svc->port;
+
+	svc->priv = sysmon;
+
+	return 0;
+}
+
+/**
+ * ssctl_del_server() - QMI callback indicating that @svc is removed
+ * @qmi:	QMI handle
+ * @svc:	service information
+ */
+static void ssctl_del_server(struct qmi_handle *qmi, struct qmi_service *svc)
+{
+	struct qcom_sysmon *sysmon = svc->priv;
+
+	sysmon->ssctl_version = 0;
+}
+
+static const struct qmi_ops ssctl_ops = {
+	.new_server = ssctl_new_server,
+	.del_server = ssctl_del_server,
+};
+
+static int sysmon_start(struct rproc_subdev *subdev)
+{
+	return 0;
+}
+
+static void sysmon_stop(struct rproc_subdev *subdev, bool crashed)
+{
+	struct qcom_sysmon *sysmon = container_of(subdev, struct qcom_sysmon, subdev);
+
+	blocking_notifier_call_chain(&sysmon_notifiers, 0, (void *)sysmon->name);
+
+	/* Don't request graceful shutdown if we've crashed */
+	if (crashed)
+		return;
+
+	if (sysmon->ssctl_version)
+		ssctl_request_shutdown(sysmon);
+	else if (sysmon->ept)
+		sysmon_request_shutdown(sysmon);
+}
+
+/**
+ * sysmon_notify() - notify sysmon target of another's SSR
+ * @nb:		notifier_block associated with sysmon instance
+ * @event:	unused
+ * @data:	SSR identifier of the remote that is going down
+ */
+static int sysmon_notify(struct notifier_block *nb, unsigned long event,
+			 void *data)
+{
+	struct qcom_sysmon *sysmon = container_of(nb, struct qcom_sysmon, nb);
+	struct rproc *rproc = sysmon->rproc;
+	const char *ssr_name = data;
+
+	/* Skip non-running rprocs and the originating instance */
+	if (rproc->state != RPROC_RUNNING || !strcmp(data, sysmon->name)) {
+		dev_dbg(sysmon->dev, "not notifying %s\n", sysmon->name);
+		return NOTIFY_DONE;
+	}
+
+	/* Only SSCTL version 2 supports SSR events */
+	if (sysmon->ssctl_version == 2)
+		ssctl_send_event(sysmon, ssr_name);
+	else if (sysmon->ept)
+		sysmon_send_event(sysmon, ssr_name);
+
+	return NOTIFY_DONE;
+}
+
+/**
+ * qcom_add_sysmon_subdev() - create a sysmon subdev for the given remoteproc
+ * @rproc:	rproc context to associate the subdev with
+ * @name:	name of this subdev, to use in SSR
+ * @ssctl_instance: instance id of the ssctl QMI service
+ *
+ * Return: A new qcom_sysmon object, or NULL on failure
+ */
+struct qcom_sysmon *qcom_add_sysmon_subdev(struct rproc *rproc,
+					   const char *name,
+					   int ssctl_instance)
+{
+	struct qcom_sysmon *sysmon;
+	int ret;
+
+	sysmon = kzalloc(sizeof(*sysmon), GFP_KERNEL);
+	if (!sysmon)
+		return NULL;
+
+	sysmon->dev = rproc->dev.parent;
+	sysmon->rproc = rproc;
+
+	sysmon->name = name;
+	sysmon->ssctl_instance = ssctl_instance;
+
+	init_completion(&sysmon->comp);
+	mutex_init(&sysmon->lock);
+
+	ret = qmi_handle_init(&sysmon->qmi, SSCTL_MAX_MSG_LEN, &ssctl_ops, NULL);
+	if (ret < 0) {
+		dev_err(sysmon->dev, "failed to initialize qmi handle\n");
+		kfree(sysmon);
+		return NULL;
+	}
+
+	qmi_add_lookup(&sysmon->qmi, 43, 0, 0);
+
+	rproc_add_subdev(rproc, &sysmon->subdev, sysmon_start, sysmon_stop);
+
+	sysmon->nb.notifier_call = sysmon_notify;
+	blocking_notifier_chain_register(&sysmon_notifiers, &sysmon->nb);
+
+	mutex_lock(&sysmon_lock);
+	list_add(&sysmon->node, &sysmon_list);
+	mutex_unlock(&sysmon_lock);
+
+	return sysmon;
+}
+EXPORT_SYMBOL_GPL(qcom_add_sysmon_subdev);
+
+/**
+ * qcom_remove_sysmon_subdev() - release a qcom_sysmon
+ * @sysmon:	sysmon context, as retrieved by qcom_add_sysmon_subdev()
+ */
+void qcom_remove_sysmon_subdev(struct qcom_sysmon *sysmon)
+{
+	if (!sysmon)
+		return;
+
+	mutex_lock(&sysmon_lock);
+	list_del(&sysmon->node);
+	mutex_unlock(&sysmon_lock);
+
+	blocking_notifier_chain_unregister(&sysmon_notifiers, &sysmon->nb);
+
+	rproc_remove_subdev(sysmon->rproc, &sysmon->subdev);
+
+	qmi_handle_release(&sysmon->qmi);
+
+	kfree(sysmon);
+}
+EXPORT_SYMBOL_GPL(qcom_remove_sysmon_subdev);
+
+/**
+ * sysmon_probe() - probe sys_mon channel
+ * @rpdev:	rpmsg device handle
+ *
+ * Find the sysmon context associated with the ancestor remoteproc and assign
+ * this rpmsg device with said sysmon context.
+ *
+ * Return: 0 on success, negative errno on failure.
+ */
+static int sysmon_probe(struct rpmsg_device *rpdev)
+{
+	struct qcom_sysmon *sysmon;
+	struct rproc *rproc;
+
+	rproc = rproc_get_by_child(&rpdev->dev);
+	if (!rproc) {
+		dev_err(&rpdev->dev, "sysmon device not child of rproc\n");
+		return -EINVAL;
+	}
+
+	mutex_lock(&sysmon_lock);
+	list_for_each_entry(sysmon, &sysmon_list, node) {
+		if (sysmon->rproc == rproc)
+			goto found;
+	}
+	mutex_unlock(&sysmon_lock);
+
+	dev_err(&rpdev->dev, "no sysmon associated with parent rproc\n");
+
+	return -EINVAL;
+
+found:
+	mutex_unlock(&sysmon_lock);
+
+	rpdev->ept->priv = sysmon;
+	sysmon->ept = rpdev->ept;
+
+	return 0;
+}
+
+/**
+ * sysmon_remove() - sys_mon channel remove handler
+ * @rpdev:	rpmsg device handle
+ *
+ * Disassociate the rpmsg device with the sysmon instance.
+ */
+static void sysmon_remove(struct rpmsg_device *rpdev)
+{
+	struct qcom_sysmon *sysmon = rpdev->ept->priv;
+
+	sysmon->ept = NULL;
+}
+
+static const struct rpmsg_device_id sysmon_match[] = {
+	{ "sys_mon" },
+	{}
+};
+
+static struct rpmsg_driver sysmon_driver = {
+	.probe = sysmon_probe,
+	.remove = sysmon_remove,
+	.callback = sysmon_callback,
+	.id_table = sysmon_match,
+	.drv = {
+		.name = "qcom_sysmon",
+	},
+};
+
+module_rpmsg_driver(sysmon_driver);
+
+MODULE_DESCRIPTION("Qualcomm sysmon driver");
+MODULE_LICENSE("GPL v2");

drivers/remoteproc/qcom_wcnss.c

@@ -40,6 +40,7 @@
 #define WCNSS_CRASH_REASON_SMEM		422
 #define WCNSS_FIRMWARE_NAME		"wcnss.mdt"
 #define WCNSS_PAS_ID			6
+#define WCNSS_SSCTL_ID			0x13
 
 #define WCNSS_SPARE_NVBIN_DLND		BIT(25)
 
@@ -98,6 +99,7 @@ struct qcom_wcnss {
 	size_t mem_size;
 
 	struct qcom_rproc_subdev smd_subdev;
+	struct qcom_sysmon *sysmon;
 };
 
 static const struct wcnss_data riva_data = {
@@ -153,7 +155,8 @@ static int wcnss_load(struct rproc *rproc, const struct firmware *fw)
 	struct qcom_wcnss *wcnss = (struct qcom_wcnss *)rproc->priv;
 
 	return qcom_mdt_load(wcnss->dev, fw, rproc->firmware, WCNSS_PAS_ID,
-			     wcnss->mem_region, wcnss->mem_phys, wcnss->mem_size);
+			     wcnss->mem_region, wcnss->mem_phys,
+			     wcnss->mem_size, &wcnss->mem_reloc);
 }
 
 static void wcnss_indicate_nv_download(struct qcom_wcnss *wcnss)
@@ -308,6 +311,7 @@ static const struct rproc_ops wcnss_ops = {
 	.start = wcnss_start,
 	.stop = wcnss_stop,
 	.da_to_va = wcnss_da_to_va,
+	.parse_fw = qcom_register_dump_segments,
 	.load = wcnss_load,
 };
 
@@ -332,9 +336,6 @@ static irqreturn_t wcnss_fatal_interrupt(int irq, void *dev)
 
 	rproc_report_crash(wcnss->rproc, RPROC_FATAL_ERROR);
 
-	if (!IS_ERR(msg))
-		msg[0] = '\0';
-
 	return IRQ_HANDLED;
 }
 
@@ -551,6 +552,7 @@ static int wcnss_probe(struct platform_device *pdev)
 	}
 
 	qcom_add_smd_subdev(rproc, &wcnss->smd_subdev);
+	wcnss->sysmon = qcom_add_sysmon_subdev(rproc, "wcnss", WCNSS_SSCTL_ID);
 
 	ret = rproc_add(rproc);
 	if (ret)
@@ -573,6 +575,7 @@ static int wcnss_remove(struct platform_device *pdev)
 	qcom_smem_state_put(wcnss->state);
 	rproc_del(wcnss->rproc);
 
+	qcom_remove_sysmon_subdev(wcnss->sysmon);
 	qcom_remove_smd_subdev(wcnss->rproc, &wcnss->smd_subdev);
 	rproc_free(wcnss->rproc);
 

drivers/remoteproc/remoteproc_core.c

@@ -33,6 +33,7 @@
 #include <linux/firmware.h>
 #include <linux/string.h>
 #include <linux/debugfs.h>
+#include <linux/devcoredump.h>
 #include <linux/remoteproc.h>
 #include <linux/iommu.h>
 #include <linux/idr.h>
@@ -307,7 +308,7 @@ static int rproc_vdev_do_probe(struct rproc_subdev *subdev)
 	return rproc_add_virtio_dev(rvdev, rvdev->id);
 }
 
-static void rproc_vdev_do_remove(struct rproc_subdev *subdev)
+static void rproc_vdev_do_remove(struct rproc_subdev *subdev, bool crashed)
 {
 	struct rproc_vdev *rvdev = container_of(subdev, struct rproc_vdev, subdev);
 
@@ -788,17 +789,31 @@ static int rproc_probe_subdevices(struct rproc *rproc)
 
 unroll_registration:
 	list_for_each_entry_continue_reverse(subdev, &rproc->subdevs, node)
-		subdev->remove(subdev);
+		subdev->remove(subdev, true);
 
 	return ret;
 }
 
-static void rproc_remove_subdevices(struct rproc *rproc)
+static void rproc_remove_subdevices(struct rproc *rproc, bool crashed)
 {
 	struct rproc_subdev *subdev;
 
 	list_for_each_entry_reverse(subdev, &rproc->subdevs, node)
-		subdev->remove(subdev);
+		subdev->remove(subdev, crashed);
+}
+
+/**
+ * rproc_coredump_cleanup() - clean up dump_segments list
+ * @rproc: the remote processor handle
+ */
+static void rproc_coredump_cleanup(struct rproc *rproc)
+{
+	struct rproc_dump_segment *entry, *tmp;
+
+	list_for_each_entry_safe(entry, tmp, &rproc->dump_segments, node) {
+		list_del(&entry->node);
+		kfree(entry);
+	}
 }
 
 /**
@@ -848,6 +863,8 @@ static void rproc_resource_cleanup(struct rproc *rproc)
 	/* clean up remote vdev entries */
 	list_for_each_entry_safe(rvdev, rvtmp, &rproc->rvdevs, node)
 		kref_put(&rvdev->refcount, rproc_vdev_release);
+
+	rproc_coredump_cleanup(rproc);
 }
 
 static int rproc_start(struct rproc *rproc, const struct firmware *fw)
@@ -927,8 +944,8 @@ static int rproc_fw_boot(struct rproc *rproc, const struct firmware *fw)
 
 	rproc->bootaddr = rproc_get_boot_addr(rproc, fw);
 
-	/* load resource table */
+	/* Load resource table, core dump segment list etc from the firmware */
-	ret = rproc_load_rsc_table(rproc, fw);
+	ret = rproc_parse_fw(rproc, fw);
 	if (ret)
 		goto disable_iommu;
 
@@ -992,13 +1009,13 @@ static int rproc_trigger_auto_boot(struct rproc *rproc)
 	return ret;
 }
 
-static int rproc_stop(struct rproc *rproc)
+static int rproc_stop(struct rproc *rproc, bool crashed)
 {
 	struct device *dev = &rproc->dev;
 	int ret;
 
 	/* remove any subdevices for the remote processor */
-	rproc_remove_subdevices(rproc);
+	rproc_remove_subdevices(rproc, crashed);
 
 	/* the installed resource table is no longer accessible */
 	rproc->table_ptr = rproc->cached_table;
@@ -1017,6 +1034,113 @@ static int rproc_stop(struct rproc *rproc)
 	return 0;
 }
 
+/**
+ * rproc_coredump_add_segment() - add segment of device memory to coredump
+ * @rproc:	handle of a remote processor
+ * @da:		device address
+ * @size:	size of segment
+ *
+ * Add device memory to the list of segments to be included in a coredump for
+ * the remoteproc.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int rproc_coredump_add_segment(struct rproc *rproc, dma_addr_t da, size_t size)
+{
+	struct rproc_dump_segment *segment;
+
+	segment = kzalloc(sizeof(*segment), GFP_KERNEL);
+	if (!segment)
+		return -ENOMEM;
+
+	segment->da = da;
+	segment->size = size;
+
+	list_add_tail(&segment->node, &rproc->dump_segments);
+
+	return 0;
+}
+EXPORT_SYMBOL(rproc_coredump_add_segment);
+
+/**
+ * rproc_coredump() - perform coredump
+ * @rproc:	rproc handle
+ *
+ * This function will generate an ELF header for the registered segments
+ * and create a devcoredump device associated with rproc.
+ */
+static void rproc_coredump(struct rproc *rproc)
+{
+	struct rproc_dump_segment *segment;
+	struct elf32_phdr *phdr;
+	struct elf32_hdr *ehdr;
+	size_t data_size;
+	size_t offset;
+	void *data;
+	void *ptr;
+	int phnum = 0;
+
+	if (list_empty(&rproc->dump_segments))
+		return;
+
+	data_size = sizeof(*ehdr);
+	list_for_each_entry(segment, &rproc->dump_segments, node) {
+		data_size += sizeof(*phdr) + segment->size;
+
+		phnum++;
+	}
+
+	data = vmalloc(data_size);
+	if (!data)
+		return;
+
+	ehdr = data;
+
+	memset(ehdr, 0, sizeof(*ehdr));
+	memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
+	ehdr->e_ident[EI_CLASS] = ELFCLASS32;
+	ehdr->e_ident[EI_DATA] = ELFDATA2LSB;
+	ehdr->e_ident[EI_VERSION] = EV_CURRENT;
+	ehdr->e_ident[EI_OSABI] = ELFOSABI_NONE;
+	ehdr->e_type = ET_CORE;
+	ehdr->e_machine = EM_NONE;
+	ehdr->e_version = EV_CURRENT;
+	ehdr->e_entry = rproc->bootaddr;
+	ehdr->e_phoff = sizeof(*ehdr);
+	ehdr->e_ehsize = sizeof(*ehdr);
+	ehdr->e_phentsize = sizeof(*phdr);
+	ehdr->e_phnum = phnum;
+
+	phdr = data + ehdr->e_phoff;
+	offset = ehdr->e_phoff + sizeof(*phdr) * ehdr->e_phnum;
+	list_for_each_entry(segment, &rproc->dump_segments, node) {
+		memset(phdr, 0, sizeof(*phdr));
+		phdr->p_type = PT_LOAD;
+		phdr->p_offset = offset;
+		phdr->p_vaddr = segment->da;
+		phdr->p_paddr = segment->da;
+		phdr->p_filesz = segment->size;
+		phdr->p_memsz = segment->size;
+		phdr->p_flags = PF_R | PF_W | PF_X;
+		phdr->p_align = 0;
+
+		ptr = rproc_da_to_va(rproc, segment->da, segment->size);
+		if (!ptr) {
+			dev_err(&rproc->dev,
+				"invalid coredump segment (%pad, %zu)\n",
+				&segment->da, segment->size);
+			memset(data + offset, 0xff, segment->size);
+		} else {
+			memcpy(data + offset, ptr, segment->size);
+		}
+
+		offset += phdr->p_filesz;
+		phdr++;
+	}
+
+	dev_coredumpv(&rproc->dev, data, data_size, GFP_KERNEL);
+}
+
 /**
  * rproc_trigger_recovery() - recover a remoteproc
  * @rproc: the remote processor
@@ -1039,10 +1163,13 @@ int rproc_trigger_recovery(struct rproc *rproc)
 	if (ret)
 		return ret;
 
-	ret = rproc_stop(rproc);
+	ret = rproc_stop(rproc, false);
 	if (ret)
 		goto unlock_mutex;
 
+	/* generate coredump */
+	rproc_coredump(rproc);
+
 	/* load firmware */
 	ret = request_firmware(&firmware_p, rproc->firmware, dev);
 	if (ret < 0) {
@@ -1189,7 +1316,7 @@ void rproc_shutdown(struct rproc *rproc)
 	if (!atomic_dec_and_test(&rproc->power))
 		goto out;
 
-	ret = rproc_stop(rproc);
+	ret = rproc_stop(rproc, true);
 	if (ret) {
 		atomic_inc(&rproc->power);
 		goto out;
@@ -1428,7 +1555,7 @@ struct rproc *rproc_alloc(struct device *dev, const char *name,
 	/* Default to ELF loader if no load function is specified */
 	if (!rproc->ops->load) {
 		rproc->ops->load = rproc_elf_load_segments;
-		rproc->ops->load_rsc_table = rproc_elf_load_rsc_table;
+		rproc->ops->parse_fw = rproc_elf_load_rsc_table;
 		rproc->ops->find_loaded_rsc_table = rproc_elf_find_loaded_rsc_table;
 		rproc->ops->sanity_check = rproc_elf_sanity_check;
 		rproc->ops->get_boot_addr = rproc_elf_get_boot_addr;
@@ -1443,6 +1570,7 @@ struct rproc *rproc_alloc(struct device *dev, const char *name,
 	INIT_LIST_HEAD(&rproc->traces);
 	INIT_LIST_HEAD(&rproc->rvdevs);
 	INIT_LIST_HEAD(&rproc->subdevs);
+	INIT_LIST_HEAD(&rproc->dump_segments);
 
 	INIT_WORK(&rproc->crash_handler, rproc_crash_handler_work);
 
@@ -1535,7 +1663,7 @@ EXPORT_SYMBOL(rproc_del);
 void rproc_add_subdev(struct rproc *rproc,
 		      struct rproc_subdev *subdev,
 		      int (*probe)(struct rproc_subdev *subdev),
-		      void (*remove)(struct rproc_subdev *subdev))
+		      void (*remove)(struct rproc_subdev *subdev, bool crashed))
 {
 	subdev->probe = probe;
 	subdev->remove = remove;

drivers/remoteproc/remoteproc_internal.h

@@ -88,11 +88,10 @@ int rproc_load_segments(struct rproc *rproc, const struct firmware *fw)
 	return -EINVAL;
 }
 
-static inline int rproc_load_rsc_table(struct rproc *rproc,
+static inline int rproc_parse_fw(struct rproc *rproc, const struct firmware *fw)
-				       const struct firmware *fw)
 {
-	if (rproc->ops->load_rsc_table)
+	if (rproc->ops->parse_fw)
-		return rproc->ops->load_rsc_table(rproc, fw);
+		return rproc->ops->parse_fw(rproc, fw);
 
 	return 0;
 }

drivers/soc/qcom/Kconfig

@@ -37,7 +37,7 @@ config QCOM_PM
 
 config QCOM_QMI_HELPERS
 	tristate
-	depends on ARCH_QCOM
+	depends on ARCH_QCOM && NET
 	help
 	  Helper library for handling QMI encoded messages.  QMI encoded
 	  messages are used in communication between the majority of QRTR

drivers/soc/qcom/mdt_loader.c

@@ -83,12 +83,14 @@ EXPORT_SYMBOL_GPL(qcom_mdt_get_size);
  * @mem_region:	allocated memory region to load firmware into
  * @mem_phys:	physical address of allocated memory region
  * @mem_size:	size of the allocated memory region
+ * @reloc_base:	adjusted physical address after relocation
  *
  * Returns 0 on success, negative errno otherwise.
  */
 int qcom_mdt_load(struct device *dev, const struct firmware *fw,
 		  const char *firmware, int pas_id, void *mem_region,
-		  phys_addr_t mem_phys, size_t mem_size)
+		  phys_addr_t mem_phys, size_t mem_size,
+		  phys_addr_t *reloc_base)
 {
 	const struct elf32_phdr *phdrs;
 	const struct elf32_phdr *phdr;
@@ -192,6 +194,9 @@ int qcom_mdt_load(struct device *dev, const struct firmware *fw,
 			memset(ptr + phdr->p_filesz, 0, phdr->p_memsz - phdr->p_filesz);
 	}
 
+	if (reloc_base)
+		*reloc_base = mem_reloc;
+
 out:
 	kfree(fw_name);
 

include/linux/remoteproc.h

@@ -344,7 +344,7 @@ struct rproc_ops {
 	int (*stop)(struct rproc *rproc);
 	void (*kick)(struct rproc *rproc, int vqid);
 	void * (*da_to_va)(struct rproc *rproc, u64 da, int len);
-	int (*load_rsc_table)(struct rproc *rproc, const struct firmware *fw);
+	int (*parse_fw)(struct rproc *rproc, const struct firmware *fw);
 	struct resource_table *(*find_loaded_rsc_table)(
 				struct rproc *rproc, const struct firmware *fw);
 	int (*load)(struct rproc *rproc, const struct firmware *fw);
@@ -394,6 +394,21 @@ enum rproc_crash_type {
 	RPROC_FATAL_ERROR,
 };
 
+/**
+ * struct rproc_dump_segment - segment info from ELF header
+ * @node:	list node related to the rproc segment list
+ * @da:		device address of the segment
+ * @size:	size of the segment
+ */
+struct rproc_dump_segment {
+	struct list_head node;
+
+	dma_addr_t da;
+	size_t size;
+
+	loff_t offset;
+};
+
 /**
  * struct rproc - represents a physical remote processor device
  * @node: list node of this rproc object
@@ -424,6 +439,7 @@ enum rproc_crash_type {
  * @cached_table: copy of the resource table
  * @table_sz: size of @cached_table
  * @has_iommu: flag to indicate if remote processor is behind an MMU
+ * @dump_segments: list of segments in the firmware
  */
 struct rproc {
 	struct list_head node;
@@ -455,19 +471,21 @@ struct rproc {
 	size_t table_sz;
 	bool has_iommu;
 	bool auto_boot;
+	struct list_head dump_segments;
 };
 
 /**
  * struct rproc_subdev - subdevice tied to a remoteproc
  * @node: list node related to the rproc subdevs list
  * @probe: probe function, called as the rproc is started
- * @remove: remove function, called as the rproc is stopped
+ * @remove: remove function, called as the rproc is being stopped, the @crashed
+ *	    parameter indicates if this originates from the a recovery
  */
 struct rproc_subdev {
 	struct list_head node;
 
 	int (*probe)(struct rproc_subdev *subdev);
-	void (*remove)(struct rproc_subdev *subdev);
+	void (*remove)(struct rproc_subdev *subdev, bool crashed);
 };
 
 /* we currently support only two vrings per rvdev */
@@ -534,6 +552,7 @@ void rproc_free(struct rproc *rproc);
 int rproc_boot(struct rproc *rproc);
 void rproc_shutdown(struct rproc *rproc);
 void rproc_report_crash(struct rproc *rproc, enum rproc_crash_type type);
+int rproc_coredump_add_segment(struct rproc *rproc, dma_addr_t da, size_t size);
 
 static inline struct rproc_vdev *vdev_to_rvdev(struct virtio_device *vdev)
 {
@@ -550,7 +569,7 @@ static inline struct rproc *vdev_to_rproc(struct virtio_device *vdev)
 void rproc_add_subdev(struct rproc *rproc,
 		      struct rproc_subdev *subdev,
 		      int (*probe)(struct rproc_subdev *subdev),
-		      void (*remove)(struct rproc_subdev *subdev));
+		      void (*remove)(struct rproc_subdev *subdev, bool graceful));
 
 void rproc_remove_subdev(struct rproc *rproc, struct rproc_subdev *subdev);
 

include/linux/soc/qcom/mdt_loader.h

@@ -14,6 +14,7 @@ struct firmware;
 ssize_t qcom_mdt_get_size(const struct firmware *fw);
 int qcom_mdt_load(struct device *dev, const struct firmware *fw,
 		  const char *fw_name, int pas_id, void *mem_region,
-		  phys_addr_t mem_phys, size_t mem_size);
+		  phys_addr_t mem_phys, size_t mem_size,
+		  phys_addr_t *reloc_base);
 
 #endif

samples/Kconfig

@@ -62,6 +62,16 @@ config SAMPLE_KDB
 	  Build an example of how to dynamically add the hello
 	  command to the kdb shell.
 
+config SAMPLE_QMI_CLIENT
+	tristate "Build qmi client sample -- loadable modules only"
+	depends on m
+	depends on ARCH_QCOM
+	depends on NET
+	select QCOM_QMI_HELPERS
+	help
+	  Build an QMI client sample driver, which demonstrates how to
+	  communicate with a remote QRTR service, using QMI encoded messages.
+
 config SAMPLE_RPMSG_CLIENT
 	tristate "Build rpmsg client sample -- loadable modules only"
 	depends on RPMSG && m

samples/Makefile

@@ -3,4 +3,4 @@
 obj-$(CONFIG_SAMPLES)	+= kobject/ kprobes/ trace_events/ livepatch/ \
 			   hw_breakpoint/ kfifo/ kdb/ hidraw/ rpmsg/ seccomp/ \
 			   configfs/ connector/ v4l/ trace_printk/ \
-			   vfio-mdev/ statx/
+			   vfio-mdev/ statx/ qmi/

samples/qmi/Makefile

@@ -0,0 +1 @@
+obj-$(CONFIG_SAMPLE_QMI_CLIENT) += qmi_sample_client.o

samples/qmi/qmi_sample_client.c

@@ -0,0 +1,622 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Sample in-kernel QMI client driver
+ *
+ * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved.
+ * Copyright (C) 2017 Linaro Ltd.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/qrtr.h>
+#include <linux/net.h>
+#include <linux/completion.h>
+#include <linux/idr.h>
+#include <linux/string.h>
+#include <net/sock.h>
+#include <linux/soc/qcom/qmi.h>
+
+#define PING_REQ1_TLV_TYPE		0x1
+#define PING_RESP1_TLV_TYPE		0x2
+#define PING_OPT1_TLV_TYPE		0x10
+#define PING_OPT2_TLV_TYPE		0x11
+
+#define DATA_REQ1_TLV_TYPE		0x1
+#define DATA_RESP1_TLV_TYPE		0x2
+#define DATA_OPT1_TLV_TYPE		0x10
+#define DATA_OPT2_TLV_TYPE		0x11
+
+#define TEST_MED_DATA_SIZE_V01		8192
+#define TEST_MAX_NAME_SIZE_V01		255
+
+#define TEST_PING_REQ_MSG_ID_V01	0x20
+#define TEST_DATA_REQ_MSG_ID_V01	0x21
+
+#define TEST_PING_REQ_MAX_MSG_LEN_V01	266
+#define TEST_DATA_REQ_MAX_MSG_LEN_V01	8456
+
+struct test_name_type_v01 {
+	u32 name_len;
+	char name[TEST_MAX_NAME_SIZE_V01];
+};
+
+static struct qmi_elem_info test_name_type_v01_ei[] = {
+	{
+		.data_type	= QMI_DATA_LEN,
+		.elem_len	= 1,
+		.elem_size	= sizeof(u8),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= QMI_COMMON_TLV_TYPE,
+		.offset		= offsetof(struct test_name_type_v01,
+					   name_len),
+	},
+	{
+		.data_type	= QMI_UNSIGNED_1_BYTE,
+		.elem_len	= TEST_MAX_NAME_SIZE_V01,
+		.elem_size	= sizeof(char),
+		.array_type	= VAR_LEN_ARRAY,
+		.tlv_type	= QMI_COMMON_TLV_TYPE,
+		.offset		= offsetof(struct test_name_type_v01,
+					   name),
+	},
+	{}
+};
+
+struct test_ping_req_msg_v01 {
+	char ping[4];
+
+	u8 client_name_valid;
+	struct test_name_type_v01 client_name;
+};
+
+static struct qmi_elem_info test_ping_req_msg_v01_ei[] = {
+	{
+		.data_type	= QMI_UNSIGNED_1_BYTE,
+		.elem_len	= 4,
+		.elem_size	= sizeof(char),
+		.array_type	= STATIC_ARRAY,
+		.tlv_type	= PING_REQ1_TLV_TYPE,
+		.offset		= offsetof(struct test_ping_req_msg_v01,
+					   ping),
+	},
+	{
+		.data_type	= QMI_OPT_FLAG,
+		.elem_len	= 1,
+		.elem_size	= sizeof(u8),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= PING_OPT1_TLV_TYPE,
+		.offset		= offsetof(struct test_ping_req_msg_v01,
+					   client_name_valid),
+	},
+	{
+		.data_type	= QMI_STRUCT,
+		.elem_len	= 1,
+		.elem_size	= sizeof(struct test_name_type_v01),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= PING_OPT1_TLV_TYPE,
+		.offset		= offsetof(struct test_ping_req_msg_v01,
+					   client_name),
+		.ei_array	= test_name_type_v01_ei,
+	},
+	{}
+};
+
+struct test_ping_resp_msg_v01 {
+	struct qmi_response_type_v01 resp;
+
+	u8 pong_valid;
+	char pong[4];
+
+	u8 service_name_valid;
+	struct test_name_type_v01 service_name;
+};
+
+static struct qmi_elem_info test_ping_resp_msg_v01_ei[] = {
+	{
+		.data_type	= QMI_STRUCT,
+		.elem_len	= 1,
+		.elem_size	= sizeof(struct qmi_response_type_v01),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= PING_RESP1_TLV_TYPE,
+		.offset		= offsetof(struct test_ping_resp_msg_v01,
+					   resp),
+		.ei_array	= qmi_response_type_v01_ei,
+	},
+	{
+		.data_type	= QMI_OPT_FLAG,
+		.elem_len	= 1,
+		.elem_size	= sizeof(u8),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= PING_OPT1_TLV_TYPE,
+		.offset		= offsetof(struct test_ping_resp_msg_v01,
+					   pong_valid),
+	},
+	{
+		.data_type	= QMI_UNSIGNED_1_BYTE,
+		.elem_len	= 4,
+		.elem_size	= sizeof(char),
+		.array_type	= STATIC_ARRAY,
+		.tlv_type	= PING_OPT1_TLV_TYPE,
+		.offset		= offsetof(struct test_ping_resp_msg_v01,
+					   pong),
+	},
+	{
+		.data_type	= QMI_OPT_FLAG,
+		.elem_len	= 1,
+		.elem_size	= sizeof(u8),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= PING_OPT2_TLV_TYPE,
+		.offset		= offsetof(struct test_ping_resp_msg_v01,
+					   service_name_valid),
+	},
+	{
+		.data_type	= QMI_STRUCT,
+		.elem_len	= 1,
+		.elem_size	= sizeof(struct test_name_type_v01),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= PING_OPT2_TLV_TYPE,
+		.offset		= offsetof(struct test_ping_resp_msg_v01,
+					   service_name),
+		.ei_array	= test_name_type_v01_ei,
+	},
+	{}
+};
+
+struct test_data_req_msg_v01 {
+	u32 data_len;
+	u8 data[TEST_MED_DATA_SIZE_V01];
+
+	u8 client_name_valid;
+	struct test_name_type_v01 client_name;
+};
+
+static struct qmi_elem_info test_data_req_msg_v01_ei[] = {
+	{
+		.data_type	= QMI_DATA_LEN,
+		.elem_len	= 1,
+		.elem_size	= sizeof(u32),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= DATA_REQ1_TLV_TYPE,
+		.offset		= offsetof(struct test_data_req_msg_v01,
+					   data_len),
+	},
+	{
+		.data_type	= QMI_UNSIGNED_1_BYTE,
+		.elem_len	= TEST_MED_DATA_SIZE_V01,
+		.elem_size	= sizeof(u8),
+		.array_type	= VAR_LEN_ARRAY,
+		.tlv_type	= DATA_REQ1_TLV_TYPE,
+		.offset		= offsetof(struct test_data_req_msg_v01,
+					   data),
+	},
+	{
+		.data_type	= QMI_OPT_FLAG,
+		.elem_len	= 1,
+		.elem_size	= sizeof(u8),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= DATA_OPT1_TLV_TYPE,
+		.offset		= offsetof(struct test_data_req_msg_v01,
+					   client_name_valid),
+	},
+	{
+		.data_type	= QMI_STRUCT,
+		.elem_len	= 1,
+		.elem_size	= sizeof(struct test_name_type_v01),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= DATA_OPT1_TLV_TYPE,
+		.offset		= offsetof(struct test_data_req_msg_v01,
+					   client_name),
+		.ei_array	= test_name_type_v01_ei,
+	},
+	{}
+};
+
+struct test_data_resp_msg_v01 {
+	struct qmi_response_type_v01 resp;
+
+	u8 data_valid;
+	u32 data_len;
+	u8 data[TEST_MED_DATA_SIZE_V01];
+
+	u8 service_name_valid;
+	struct test_name_type_v01 service_name;
+};
+
+static struct qmi_elem_info test_data_resp_msg_v01_ei[] = {
+	{
+		.data_type	= QMI_STRUCT,
+		.elem_len	= 1,
+		.elem_size	= sizeof(struct qmi_response_type_v01),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= DATA_RESP1_TLV_TYPE,
+		.offset		= offsetof(struct test_data_resp_msg_v01,
+					   resp),
+		.ei_array	= qmi_response_type_v01_ei,
+	},
+	{
+		.data_type	= QMI_OPT_FLAG,
+		.elem_len	= 1,
+		.elem_size	= sizeof(u8),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= DATA_OPT1_TLV_TYPE,
+		.offset		= offsetof(struct test_data_resp_msg_v01,
+					   data_valid),
+	},
+	{
+		.data_type	= QMI_DATA_LEN,
+		.elem_len	= 1,
+		.elem_size	= sizeof(u32),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= DATA_OPT1_TLV_TYPE,
+		.offset		= offsetof(struct test_data_resp_msg_v01,
+					   data_len),
+	},
+	{
+		.data_type	= QMI_UNSIGNED_1_BYTE,
+		.elem_len	= TEST_MED_DATA_SIZE_V01,
+		.elem_size	= sizeof(u8),
+		.array_type	= VAR_LEN_ARRAY,
+		.tlv_type	= DATA_OPT1_TLV_TYPE,
+		.offset		= offsetof(struct test_data_resp_msg_v01,
+					   data),
+	},
+	{
+		.data_type	= QMI_OPT_FLAG,
+		.elem_len	= 1,
+		.elem_size	= sizeof(u8),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= DATA_OPT2_TLV_TYPE,
+		.offset		= offsetof(struct test_data_resp_msg_v01,
+					   service_name_valid),
+	},
+	{
+		.data_type	= QMI_STRUCT,
+		.elem_len	= 1,
+		.elem_size	= sizeof(struct test_name_type_v01),
+		.array_type	= NO_ARRAY,
+		.tlv_type	= DATA_OPT2_TLV_TYPE,
+		.offset		= offsetof(struct test_data_resp_msg_v01,
+					   service_name),
+		.ei_array	= test_name_type_v01_ei,
+	},
+	{}
+};
+
+/*
+ * ping_write() - ping_pong debugfs file write handler
+ * @file:	debugfs file context
+ * @user_buf:	reference to the user data (ignored)
+ * @count:	number of bytes in @user_buf
+ * @ppos:	offset in @file to write
+ *
+ * This function allows user space to send out a ping_pong QMI encoded message
+ * to the associated remote test service and will return with the result of the
+ * transaction. It serves as an example of how to provide a custom response
+ * handler.
+ *
+ * Return: @count, or negative errno on failure.
+ */
+static ssize_t ping_write(struct file *file, const char __user *user_buf,
+			  size_t count, loff_t *ppos)
+{
+	struct qmi_handle *qmi = file->private_data;
+	struct test_ping_req_msg_v01 req = {};
+	struct qmi_txn txn;
+	int ret;
+
+	memcpy(req.ping, "ping", sizeof(req.ping));
+
+	ret = qmi_txn_init(qmi, &txn, NULL, NULL);
+	if (ret < 0)
+		return ret;
+
+	ret = qmi_send_request(qmi, NULL, &txn,
+			       TEST_PING_REQ_MSG_ID_V01,
+			       TEST_PING_REQ_MAX_MSG_LEN_V01,
+			       test_ping_req_msg_v01_ei, &req);
+	if (ret < 0) {
+		qmi_txn_cancel(&txn);
+		return ret;
+	}
+
+	ret = qmi_txn_wait(&txn, 5 * HZ);
+	if (ret < 0)
+		count = ret;
+
+	return count;
+}
+
+static const struct file_operations ping_fops = {
+	.open = simple_open,
+	.write = ping_write,
+};
+
+static void ping_pong_cb(struct qmi_handle *qmi, struct sockaddr_qrtr *sq,
+			 struct qmi_txn *txn, const void *data)
+{
+	const struct test_ping_resp_msg_v01 *resp = data;
+
+	if (!txn) {
+		pr_err("spurious ping response\n");
+		return;
+	}
+
+	if (resp->resp.result == QMI_RESULT_FAILURE_V01)
+		txn->result = -ENXIO;
+	else if (!resp->pong_valid || memcmp(resp->pong, "pong", 4))
+		txn->result = -EINVAL;
+
+	complete(&txn->completion);
+}
+
+/*
+ * data_write() - data debugfs file write handler
+ * @file:	debugfs file context
+ * @user_buf:	reference to the user data
+ * @count:	number of bytes in @user_buf
+ * @ppos:	offset in @file to write
+ *
+ * This function allows user space to send out a data QMI encoded message to
+ * the associated remote test service and will return with the result of the
+ * transaction. It serves as an example of how to have the QMI helpers decode a
+ * transaction response into a provided object automatically.
+ *
+ * Return: @count, or negative errno on failure.
+ */
+static ssize_t data_write(struct file *file, const char __user *user_buf,
+			  size_t count, loff_t *ppos)
+
+{
+	struct qmi_handle *qmi = file->private_data;
+	struct test_data_resp_msg_v01 *resp;
+	struct test_data_req_msg_v01 *req;
+	struct qmi_txn txn;
+	int ret;
+
+	req = kzalloc(sizeof(*req), GFP_KERNEL);
+	if (!req)
+		return -ENOMEM;
+
+	resp = kzalloc(sizeof(*resp), GFP_KERNEL);
+	if (!resp) {
+		kfree(req);
+		return -ENOMEM;
+	}
+
+	req->data_len = min_t(size_t, sizeof(req->data), count);
+	if (copy_from_user(req->data, user_buf, req->data_len)) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+	ret = qmi_txn_init(qmi, &txn, test_data_resp_msg_v01_ei, resp);
+	if (ret < 0)
+		goto out;
+
+	ret = qmi_send_request(qmi, NULL, &txn,
+			       TEST_DATA_REQ_MSG_ID_V01,
+			       TEST_DATA_REQ_MAX_MSG_LEN_V01,
+			       test_data_req_msg_v01_ei, req);
+	if (ret < 0) {
+		qmi_txn_cancel(&txn);
+		goto out;
+	}
+
+	ret = qmi_txn_wait(&txn, 5 * HZ);
+	if (ret < 0) {
+		goto out;
+	} else if (!resp->data_valid ||
+		   resp->data_len != req->data_len ||
+		   memcmp(resp->data, req->data, req->data_len)) {
+		pr_err("response data doesn't match expectation\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = count;
+
+out:
+	kfree(resp);
+	kfree(req);
+
+	return ret;
+}
+
+static const struct file_operations data_fops = {
+	.open = simple_open,
+	.write = data_write,
+};
+
+static struct qmi_msg_handler qmi_sample_handlers[] = {
+	{
+		.type = QMI_RESPONSE,
+		.msg_id = TEST_PING_REQ_MSG_ID_V01,
+		.ei = test_ping_resp_msg_v01_ei,
+		.decoded_size = sizeof(struct test_ping_req_msg_v01),
+		.fn = ping_pong_cb
+	},
+	{}
+};
+
+struct qmi_sample {
+	struct qmi_handle qmi;
+
+	struct dentry *de_dir;
+	struct dentry *de_data;
+	struct dentry *de_ping;
+};
+
+static struct dentry *qmi_debug_dir;
+
+static int qmi_sample_probe(struct platform_device *pdev)
+{
+	struct sockaddr_qrtr *sq;
+	struct qmi_sample *sample;
+	char path[20];
+	int ret;
+
+	sample = devm_kzalloc(&pdev->dev, sizeof(*sample), GFP_KERNEL);
+	if (!sample)
+		return -ENOMEM;
+
+	ret = qmi_handle_init(&sample->qmi, TEST_DATA_REQ_MAX_MSG_LEN_V01,
+			      NULL,
+			      qmi_sample_handlers);
+	if (ret < 0)
+		return ret;
+
+	sq = dev_get_platdata(&pdev->dev);
+	ret = kernel_connect(sample->qmi.sock, (struct sockaddr *)sq,
+			     sizeof(*sq), 0);
+	if (ret < 0) {
+		pr_err("failed to connect to remote service port\n");
+		goto err_release_qmi_handle;
+	}
+
+	snprintf(path, sizeof(path), "%d:%d", sq->sq_node, sq->sq_port);
+
+	sample->de_dir = debugfs_create_dir(path, qmi_debug_dir);
+	if (IS_ERR(sample->de_dir)) {
+		ret = PTR_ERR(sample->de_dir);
+		goto err_release_qmi_handle;
+	}
+
+	sample->de_data = debugfs_create_file("data", 0600, sample->de_dir,
+					      sample, &data_fops);
+	if (IS_ERR(sample->de_data)) {
+		ret = PTR_ERR(sample->de_data);
+		goto err_remove_de_dir;
+	}
+
+	sample->de_ping = debugfs_create_file("ping", 0600, sample->de_dir,
+					      sample, &ping_fops);
+	if (IS_ERR(sample->de_ping)) {
+		ret = PTR_ERR(sample->de_ping);
+		goto err_remove_de_data;
+	}
+
+	platform_set_drvdata(pdev, sample);
+
+	return 0;
+
+err_remove_de_data:
+	debugfs_remove(sample->de_data);
+err_remove_de_dir:
+	debugfs_remove(sample->de_dir);
+err_release_qmi_handle:
+	qmi_handle_release(&sample->qmi);
+
+	return ret;
+}
+
+static int qmi_sample_remove(struct platform_device *pdev)
+{
+	struct qmi_sample *sample = platform_get_drvdata(pdev);
+
+	debugfs_remove(sample->de_ping);
+	debugfs_remove(sample->de_data);
+	debugfs_remove(sample->de_dir);
+
+	qmi_handle_release(&sample->qmi);
+
+	return 0;
+}
+
+static struct platform_driver qmi_sample_driver = {
+	.probe = qmi_sample_probe,
+	.remove = qmi_sample_remove,
+	.driver = {
+		.name = "qmi_sample_client",
+	},
+};
+
+static int qmi_sample_new_server(struct qmi_handle *qmi,
+				 struct qmi_service *service)
+{
+	struct platform_device *pdev;
+	struct sockaddr_qrtr sq = { AF_QIPCRTR, service->node, service->port };
+	int ret;
+
+	pdev = platform_device_alloc("qmi_sample_client", PLATFORM_DEVID_AUTO);
+	if (!pdev)
+		return -ENOMEM;
+
+	ret = platform_device_add_data(pdev, &sq, sizeof(sq));
+	if (ret)
+		goto err_put_device;
+
+	ret = platform_device_add(pdev);
+	if (ret)
+		goto err_put_device;
+
+	service->priv = pdev;
+
+	return 0;
+
+err_put_device:
+	platform_device_put(pdev);
+
+	return ret;
+}
+
+static void qmi_sample_del_server(struct qmi_handle *qmi,
+				  struct qmi_service *service)
+{
+	struct platform_device *pdev = service->priv;
+
+	platform_device_unregister(pdev);
+}
+
+static struct qmi_handle lookup_client;
+
+static struct qmi_ops lookup_ops = {
+	.new_server = qmi_sample_new_server,
+	.del_server = qmi_sample_del_server,
+};
+
+static int qmi_sample_init(void)
+{
+	int ret;
+
+	qmi_debug_dir = debugfs_create_dir("qmi_sample", NULL);
+	if (IS_ERR(qmi_debug_dir)) {
+		pr_err("failed to create qmi_sample dir\n");
+		return PTR_ERR(qmi_debug_dir);
+	}
+
+	ret = platform_driver_register(&qmi_sample_driver);
+	if (ret)
+		goto err_remove_debug_dir;
+
+	ret = qmi_handle_init(&lookup_client, 0, &lookup_ops, NULL);
+	if (ret < 0)
+		goto err_unregister_driver;
+
+	qmi_add_lookup(&lookup_client, 15, 0, 0);
+
+	return 0;
+
+err_unregister_driver:
+	platform_driver_unregister(&qmi_sample_driver);
+err_remove_debug_dir:
+	debugfs_remove(qmi_debug_dir);
+
+	return ret;
+}
+
+static void qmi_sample_exit(void)
+{
+	qmi_handle_release(&lookup_client);
+
+	platform_driver_unregister(&qmi_sample_driver);
+
+	debugfs_remove(qmi_debug_dir);
+}
+
+module_init(qmi_sample_init);
+module_exit(qmi_sample_exit);
+
+MODULE_DESCRIPTION("Sample QMI client driver");
+MODULE_LICENSE("GPL v2");