--- zzzz-none-000/linux-4.19.183/drivers/tty/sysrq.c	2021-03-24 10:07:39.000000000 +0000
+++ bcm63-7530ax-756/linux-4.19.183/drivers/tty/sysrq.c	2023-06-28 08:54:20.000000000 +0000
@@ -50,6 +50,9 @@
 #include <linux/syscalls.h>
 #include <linux/of.h>
 #include <linux/rcupdate.h>
+#if defined(CONFIG_BCM_KF_WDT)
+#include <linux/watchdog.h>
+#endif
 
 #include <asm/ptrace.h>
 #include <asm/irq_regs.h>
@@ -431,6 +434,92 @@
 	.enable_mask	= SYSRQ_ENABLE_RTNICE,
 };
 
+#ifdef CONFIG_BCM_KF_CHAR_SYSRQ
+
+/*
+ * This function is a "safe" function to call at anytime.  It should only
+ * read data that do not require a lock and will not cause exceptions,
+ * i.e. reading statistics but not dereferencing pointers.  It should not
+ * assume interrupts are working on any of the CPU's.
+ * The 'L' option is also good.
+ */
+static void sysrq_handle_cpu_summary(int key)
+{
+	int cpu;
+	int max_cpu=1;
+#ifdef CONFIG_SMP
+	max_cpu=2;
+	cpumask_t available_cpus;
+
+        cpumask_copy(&available_cpus, cpu_present_mask);
+#endif
+
+
+	pr_info("CPU summary invoked on cpu %d\n", smp_processor_id());
+#ifdef CONFIG_SMP
+	for_each_cpu(cpu, &available_cpus) {
+#else
+	for (cpu=0; cpu < max_cpu; cpu++) {
+#endif
+		if (cpu_online(cpu)) {
+			pr_info("  cpu %d is online.\n", cpu);
+		}
+		else {
+			pr_info("  WARNING: cpu %d is offline!\n", cpu);
+		}
+	}
+	pr_info("\n\n");
+	// dump interrupt statistics
+	// print other CPU info that does not require getting a lock or
+	// interrupts to be enabled on that CPU
+}
+
+static struct sysrq_key_op sysrq_cpu_summary_op = {
+	.handler	= sysrq_handle_cpu_summary,
+	.help_msg	= "BRCM: show summary status on all CPUs(A)",
+	.action_msg	= "CPU Summary Status",
+	.enable_mask	= 0x4000,   /* typically all flags will be enabled */
+};
+
+
+#include <linux/seq_file.h>
+#include <linux/interrupt.h>
+
+static char intrs_output_buf[1024];
+
+static void sysrq_handle_show_intrs(int key)
+{
+	struct seq_file intrs_seq_file;
+	loff_t pos=0;
+
+	// Just initialize the parts of seq_file that seq_printf needs
+	memset(&intrs_seq_file, 0, sizeof(intrs_seq_file));
+	intrs_seq_file.buf = intrs_output_buf;
+	intrs_seq_file.size = sizeof(intrs_output_buf);
+
+	/*
+	 * Leverage the show_interrupts() function in kernel/mips/irq.c to dump
+	 * to our buffer.
+	 */
+	while (pos <= NR_IRQS)
+	{
+		memset(intrs_output_buf, 0, sizeof(intrs_output_buf));
+		intrs_seq_file.count = 0;
+		show_interrupts(&intrs_seq_file, &pos);
+		printk("%s", intrs_output_buf);
+		pos++;
+	}
+}
+
+static struct sysrq_key_op sysrq_show_intrs_op = {
+	.handler	= sysrq_handle_show_intrs,
+	.help_msg	= "BRCM: show interrupt counts on all CPUs(Y)",
+	.action_msg	= "Interrupt Counts",
+	.enable_mask	= 0x4000,   /* typically all flags will be enabled */
+};
+
+#endif /* CONFIG_BCM_KF_CHAR_SYSRQ */
+
 /* Key Operations table and lock */
 static DEFINE_SPINLOCK(sysrq_key_table_lock);
 
@@ -446,11 +535,15 @@
 	&sysrq_loglevel_op,		/* 8 */
 	&sysrq_loglevel_op,		/* 9 */
 
+#if defined(CONFIG_BCM_KF_CHAR_SYSRQ)
+	&sysrq_cpu_summary_op,		/* a*/
+#else
 	/*
 	 * a: Don't use for system provided sysrqs, it is handled specially on
 	 * sparc and will never arrive.
 	 */
 	NULL,				/* a */
+#endif
 	&sysrq_reboot_op,		/* b */
 	&sysrq_crash_op,		/* c */
 	&sysrq_showlocks_op,		/* d */
@@ -488,8 +581,12 @@
 	/* x: May be registered on ppc/powerpc for xmon */
 	/* x: May be registered on sparc64 for global PMU dump */
 	NULL,				/* x */
+#if defined(CONFIG_BCM_KF_CHAR_SYSRQ)
+	&sysrq_show_intrs_op,		/* y */
+#else
 	/* y: May be registered on sparc64 for global register dump */
 	NULL,				/* y */
+#endif
 	&sysrq_ftrace_dump_op,		/* z */
 };
 
@@ -502,6 +599,10 @@
 		retval = key - '0';
 	else if ((key >= 'a') && (key <= 'z'))
 		retval = key + 10 - 'a';
+#if defined(CONFIG_BCM_KF_CHAR_SYSRQ)
+	else if ((key >= 'A') && (key <= 'Z'))
+		retval = key + 10 - 'A';
+#endif
 	else
 		retval = -1;
 	return retval;
@@ -536,8 +637,19 @@
 	int orig_log_level;
 	int i;
 
+#if defined(CONFIG_BCM_KF_WDT)
+#if defined(CONFIG_WATCHDOG_CORE)
+	/* Kill the watchdog */
+	watchdog_force_disable();
+#endif	
+#endif
+
 	rcu_sysrq_start();
 	rcu_read_lock();
+#if defined(CONFIG_BCM_KF_CHAR_SYSRQ)
+	pr_info("SysRq: intr handled on CPU %d\n", smp_processor_id());
+#endif
+
 	/*
 	 * Raise the apparent loglevel to maximum so that the sysrq header
 	 * is shown to provide the user with positive feedback.  We do not
@@ -577,6 +689,9 @@
 			}
 		}
 		pr_cont("\n");
+#if defined(CONFIG_BCM_KF_CHAR_SYSRQ)
+		pr_info("All commands are case insensitive.\n");
+#endif
 		console_loglevel = orig_log_level;
 	}
 	rcu_read_unlock();