1 files changed, 52 insertions, 17 deletions

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 4c2246fe5dbe..15579cba1a88 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1581,6 +1581,9 @@ static unsigned long *its_lpi_alloc(int nr_irqs, u32 *base, int *nr_ids)
 		nr_irqs /= 2;
 	} while (nr_irqs > 0);
 
+	if (!nr_irqs)
+		err = -ENOSPC;
+
 	if (err)
 		goto out;
 
@@ -1951,6 +1954,29 @@ static void its_free_pending_table(struct page *pt)
 		   get_order(max_t(u32, LPI_PENDBASE_SZ, SZ_64K)));
 }
 
+static u64 its_clear_vpend_valid(void __iomem *vlpi_base)
+{
+	u32 count = 1000000;	/* 1s! */
+	bool clean;
+	u64 val;
+
+	val = gits_read_vpendbaser(vlpi_base + GICR_VPENDBASER);
+	val &= ~GICR_VPENDBASER_Valid;
+	gits_write_vpendbaser(val, vlpi_base + GICR_VPENDBASER);
+
+	do {
+		val = gits_read_vpendbaser(vlpi_base + GICR_VPENDBASER);
+		clean = !(val & GICR_VPENDBASER_Dirty);
+		if (!clean) {
+			count--;
+			cpu_relax();
+			udelay(1);
+		}
+	} while (!clean && count);
+
+	return val;
+}
+
 static void its_cpu_init_lpis(void)
 {
 	void __iomem *rbase = gic_data_rdist_rd_base();
@@ -2024,6 +2050,30 @@ static void its_cpu_init_lpis(void)
 	val |= GICR_CTLR_ENABLE_LPIS;
 	writel_relaxed(val, rbase + GICR_CTLR);
 
+	if (gic_rdists->has_vlpis) {
+		void __iomem *vlpi_base = gic_data_rdist_vlpi_base();
+
+		/*
+		 * It's possible for CPU to receive VLPIs before it is
+		 * sheduled as a vPE, especially for the first CPU, and the
+		 * VLPI with INTID larger than 2^(IDbits+1) will be considered
+		 * as out of range and dropped by GIC.
+		 * So we initialize IDbits to known value to avoid VLPI drop.
+		 */
+		val = (LPI_NRBITS - 1) & GICR_VPROPBASER_IDBITS_MASK;
+		pr_debug("GICv4: CPU%d: Init IDbits to 0x%llx for GICR_VPROPBASER\n",
+			smp_processor_id(), val);
+		gits_write_vpropbaser(val, vlpi_base + GICR_VPROPBASER);
+
+		/*
+		 * Also clear Valid bit of GICR_VPENDBASER, in case some
+		 * ancient programming gets left in and has possibility of
+		 * corrupting memory.
+		 */
+		val = its_clear_vpend_valid(vlpi_base);
+		WARN_ON(val & GICR_VPENDBASER_Dirty);
+	}
+
 	/* Make sure the GIC has seen the above */
 	dsb(sy);
 }
@@ -2644,26 +2694,11 @@ static void its_vpe_schedule(struct its_vpe *vpe)
 static void its_vpe_deschedule(struct its_vpe *vpe)
 {
 	void __iomem *vlpi_base = gic_data_rdist_vlpi_base();
-	u32 count = 1000000;	/* 1s! */
-	bool clean;
 	u64 val;
 
-	/* We're being scheduled out */
-	val = gits_read_vpendbaser(vlpi_base + GICR_VPENDBASER);
-	val &= ~GICR_VPENDBASER_Valid;
-	gits_write_vpendbaser(val, vlpi_base + GICR_VPENDBASER);
-
-	do {
-		val = gits_read_vpendbaser(vlpi_base + GICR_VPENDBASER);
-		clean = !(val & GICR_VPENDBASER_Dirty);
-		if (!clean) {
-			count--;
-			cpu_relax();
-			udelay(1);
-		}
-	} while (!clean && count);
+	val = its_clear_vpend_valid(vlpi_base);
 
-	if (unlikely(!clean && !count)) {
+	if (unlikely(val & GICR_VPENDBASER_Dirty)) {
 		pr_err_ratelimited("ITS virtual pending table not cleaning\n");
 		vpe->idai = false;
 		vpe->pending_last = true;