Merge tag 'rproc-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/andersson/remoteproc

Pull remoteproc updates from Bjorn Andersson:
 "This introduces a new "detached" state for remote processors that are
  deemed to be running at the time Linux boots and the infrastructure
  for "attaching" to these. It then introduces the support for
  performing this operation for the STM32 platform.

  The coredump functionality is moved out from the core file and gains
  support for an optional mode where the recovery phase awaits the
  notification from devcoredump that the dump should be released. This
  allows userspace to grab the coredump in scenarios where vmalloc space
  is too low for creating a complete copy of the coredump before handing
  this to devcoredump.

  A new character device based interface is introduced to allow tying
  the stoppage of a remote processor to the termination of a user space
  process. This is useful in situations when such process provides
  crucial resources/operations for the firmware running on the remote
  processor.

  The Texas Instrument K3 driver gains support for the C66x and C71x
  DSPs.

  Qualcomm remoteprocs gains support for stashing relocation information
  in IMEM, to aid post mortem debugging and the crash notification
  mechanism is generalized to be reusable in cases where loosely coupled
  drivers needs to know about the status of a remote processor. One such
  example is the IPA hardware block, which is jointly owned with the
  modem and migrated to this improved interface.

  It also introduces a number of bug fixes and debug improvements for
  the Qualcomm modem remoteproc driver.

  And it cleans up the inconsistent interface for remoteproc drivers to
  implement power management"

* tag 'rproc-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/andersson/remoteproc: (56 commits)
  remoteproc: core: Register the character device interface
  remoteproc: Add remoteproc character device interface
  remoteproc: kill IPA notify code
  net: ipa: new notification infrastructure
  remoteproc: k3-dsp: Add support for C71x DSPs
  dt-bindings: remoteproc: k3-dsp: Update bindings for C71x DSPs
  remoteproc: k3-dsp: Add support for L2RAM loading on C66x DSPs
  remoteproc: k3-dsp: Add a remoteproc driver of K3 C66x DSPs
  dt-bindings: remoteproc: Add bindings for C66x DSPs on TI K3 SoCs
  remoteproc: k3: Add TI-SCI processor control helper functions
  remoteproc: Introduce rproc_of_parse_firmware() helper
  dt-bindings: arm: keystone: Add common TI SCI bindings
  remoteproc: qcom_q6v5_mss: Remove redundant running state
  remoteproc: qcom: q6v5: Update running state before requesting stop
  remoteproc: qcom_q6v5_mss: Add modem debug policy support
  remoteproc: qcom_q6v5_mss: Validate modem blob firmware size before load
  remoteproc: qcom_q6v5_mss: Validate MBA firmware size before load
  rpmsg: update documentation
  remoteproc: qcom_q6v5_mss: Add MBA log extraction support
  remoteproc: Add coredump debugfs entry
  ...

1 files changed, 90 insertions, 0 deletions

diff --git a/drivers/remoteproc/remoteproc_debugfs.c b/drivers/remoteproc/remoteproc_debugfs.c
index 732770e92b99..2e3b3e22e1d0 100644
--- a/drivers/remoteproc/remoteproc_debugfs.c
+++ b/drivers/remoteproc/remoteproc_debugfs.c
@@ -28,6 +28,94 @@
 static struct dentry *rproc_dbg;
 
 /*
+ * A coredump-configuration-to-string lookup table, for exposing a
+ * human readable configuration via debugfs. Always keep in sync with
+ * enum rproc_coredump_mechanism
+ */
+static const char * const rproc_coredump_str[] = {
+	[RPROC_COREDUMP_DEFAULT]	= "default",
+	[RPROC_COREDUMP_INLINE]		= "inline",
+	[RPROC_COREDUMP_DISABLED]	= "disabled",
+};
+
+/* Expose the current coredump configuration via debugfs */
+static ssize_t rproc_coredump_read(struct file *filp, char __user *userbuf,
+				   size_t count, loff_t *ppos)
+{
+	struct rproc *rproc = filp->private_data;
+	char buf[20];
+	int len;
+
+	len = scnprintf(buf, sizeof(buf), "%s\n",
+			rproc_coredump_str[rproc->dump_conf]);
+
+	return simple_read_from_buffer(userbuf, count, ppos, buf, len);
+}
+
+/*
+ * By writing to the 'coredump' debugfs entry, we control the behavior of the
+ * coredump mechanism dynamically. The default value of this entry is "default".
+ *
+ * The 'coredump' debugfs entry supports these commands:
+ *
+ * default:	This is the default coredump mechanism. When the remoteproc
+ *		crashes the entire coredump will be copied to a separate buffer
+ *		and exposed to userspace.
+ *
+ * inline:	The coredump will not be copied to a separate buffer and the
+ *		recovery process will have to wait until data is read by
+ *		userspace. But this avoid usage of extra memory.
+ *
+ * disabled:	This will disable coredump. Recovery will proceed without
+ *		collecting any dump.
+ */
+static ssize_t rproc_coredump_write(struct file *filp,
+				    const char __user *user_buf, size_t count,
+				    loff_t *ppos)
+{
+	struct rproc *rproc = filp->private_data;
+	int ret, err = 0;
+	char buf[20];
+
+	if (count > sizeof(buf))
+		return -EINVAL;
+
+	ret = copy_from_user(buf, user_buf, count);
+	if (ret)
+		return -EFAULT;
+
+	/* remove end of line */
+	if (buf[count - 1] == '\n')
+		buf[count - 1] = '\0';
+
+	if (rproc->state == RPROC_CRASHED) {
+		dev_err(&rproc->dev, "can't change coredump configuration\n");
+		err = -EBUSY;
+		goto out;
+	}
+
+	if (!strncmp(buf, "disable", count)) {
+		rproc->dump_conf = RPROC_COREDUMP_DISABLED;
+	} else if (!strncmp(buf, "inline", count)) {
+		rproc->dump_conf = RPROC_COREDUMP_INLINE;
+	} else if (!strncmp(buf, "default", count)) {
+		rproc->dump_conf = RPROC_COREDUMP_DEFAULT;
+	} else {
+		dev_err(&rproc->dev, "Invalid coredump configuration\n");
+		err = -EINVAL;
+	}
+out:
+	return err ? err : count;
+}
+
+static const struct file_operations rproc_coredump_fops = {
+	.read = rproc_coredump_read,
+	.write = rproc_coredump_write,
+	.open = simple_open,
+	.llseek = generic_file_llseek,
+};
+
+/*
  * Some remote processors may support dumping trace logs into a shared
  * memory buffer. We expose this trace buffer using debugfs, so users
  * can easily tell what's going on remotely.
@@ -337,6 +425,8 @@ void rproc_create_debug_dir(struct rproc *rproc)
 			    rproc, &rproc_rsc_table_fops);
 	debugfs_create_file("carveout_memories", 0400, rproc->dbg_dir,
 			    rproc, &rproc_carveouts_fops);
+	debugfs_create_file("coredump", 0600, rproc->dbg_dir,
+			    rproc, &rproc_coredump_fops);
 }
 
 void __init rproc_init_debugfs(void)