1 files changed, 29 insertions, 7 deletions

diff --git a/drivers/irqchip/irq-riscv-imsic-early.c b/drivers/irqchip/irq-riscv-imsic-early.c
index c5c2e6929a2f..2709cacf4855 100644
--- a/drivers/irqchip/irq-riscv-imsic-early.c
+++ b/drivers/irqchip/irq-riscv-imsic-early.c
@@ -8,6 +8,7 @@
 #include <linux/acpi.h>
 #include <linux/cpu.h>
 #include <linux/interrupt.h>
+#include <linux/init.h>
 #include <linux/io.h>
 #include <linux/irq.h>
 #include <linux/irqchip.h>
@@ -21,23 +22,37 @@
 #include "irq-riscv-imsic-state.h"
 
 static int imsic_parent_irq;
+bool imsic_noipi __ro_after_init;
+
+static int __init imsic_noipi_cfg(char *buf)
+{
+	imsic_noipi = true;
+	return 0;
+}
+early_param("irqchip.riscv_imsic_noipi", imsic_noipi_cfg);
 
 #ifdef CONFIG_SMP
 static void imsic_ipi_send(unsigned int cpu)
 {
 	struct imsic_local_config *local = per_cpu_ptr(imsic->global.local, cpu);
 
-	writel_relaxed(IMSIC_IPI_ID, local->msi_va);
+	writel(IMSIC_IPI_ID, local->msi_va);
 }
 
 static void imsic_ipi_starting_cpu(void)
 {
+	if (imsic_noipi)
+		return;
+
 	/* Enable IPIs for current CPU. */
 	__imsic_id_set_enable(IMSIC_IPI_ID);
 }
 
 static void imsic_ipi_dying_cpu(void)
 {
+	if (imsic_noipi)
+		return;
+
 	/* Disable IPIs for current CPU. */
 	__imsic_id_clear_enable(IMSIC_IPI_ID);
 }
@@ -46,6 +61,9 @@ static int __init imsic_ipi_domain_init(void)
 {
 	int virq;
 
+	if (imsic_noipi)
+		return 0;
+
 	/* Create IMSIC IPI multiplexing */
 	virq = ipi_mux_create(IMSIC_NR_IPI, imsic_ipi_send);
 	if (virq <= 0)
@@ -73,16 +91,22 @@ static int __init imsic_ipi_domain_init(void) { return 0; }
 static void imsic_handle_irq(struct irq_desc *desc)
 {
 	struct irq_chip *chip = irq_desc_get_chip(desc);
-	int err, cpu = smp_processor_id();
+	int cpu = smp_processor_id();
 	struct imsic_vector *vec;
 	unsigned long local_id;
 
+	/*
+	 * Process pending local synchronization instead of waiting
+	 * for per-CPU local timer to expire.
+	 */
+	imsic_local_sync_all(false);
+
 	chained_irq_enter(chip, desc);
 
 	while ((local_id = csr_swap(CSR_TOPEI, 0))) {
 		local_id >>= TOPEI_ID_SHIFT;
 
-		if (local_id == IMSIC_IPI_ID) {
+		if (!imsic_noipi && local_id == IMSIC_IPI_ID) {
 			if (IS_ENABLED(CONFIG_SMP))
 				ipi_mux_process();
 			continue;
@@ -97,9 +121,7 @@ static void imsic_handle_irq(struct irq_desc *desc)
 			continue;
 		}
 
-		err = generic_handle_domain_irq(imsic->base_domain, vec->hwirq);
-		if (unlikely(err))
-			pr_warn_ratelimited("hwirq 0x%x mapping not found\n", vec->hwirq);
+		generic_handle_irq(vec->irq);
 	}
 
 	chained_irq_exit(chip, desc);
@@ -120,7 +142,7 @@ static int imsic_starting_cpu(unsigned int cpu)
 	 * Interrupts identities might have been enabled/disabled while
 	 * this CPU was not running so sync-up local enable/disable state.
 	 */
-	imsic_local_sync_all();
+	imsic_local_sync_all(true);
 
 	/* Enable local interrupt delivery */
 	imsic_local_delivery(true);