From:   =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>
To:     Andrew Lunn <andrew@lunn.ch>,
        Gregory Clement <gregory.clement@bootlin.com>,
        Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Marc Zyngier <maz@kernel.org>,
        =?UTF-8?q?Marek=20Beh=C3=BAn?= <kabel@kernel.org>
Cc:     linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: [PATCH 2/2] irqchip/armada-370-xp: Fix support for Multi-MSI interrupts
Date:   Thu, 25 Nov 2021 14:00:57 +0100
Message-Id: <20211125130057.26705-2-pali@kernel.org>
In-Reply-To: <20211125130057.26705-1-pali@kernel.org>
References: <20211125130057.26705-1-pali@kernel.org>
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Precedence: bulk

irq-armada-370-xp driver already sets MSI_FLAG_MULTI_PCI_MSI flag into
msi_domain_info structure. But allocated interrupt numbers for Multi-MSI
needs to be properly aligned otherwise devices send MSI interrupt with
wrong number.

Fix this issue by using function bitmap_find_free_region() instead of
bitmap_find_next_zero_area() to allocate aligned interrupt numbers.

Signed-off-by: Pali Rohár <pali@kernel.org>
Fixes: a71b9412c90c ("irqchip/armada-370-xp: Allow allocation of multiple MSIs")
Cc: stable@vger.kernel.org
---
 drivers/irqchip/irq-armada-370-xp.c | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/drivers/irqchip/irq-armada-370-xp.c b/drivers/irqchip/irq-armada-370-xp.c
index 41ad745cf343..5b8d571c041d 100644
--- a/drivers/irqchip/irq-armada-370-xp.c
+++ b/drivers/irqchip/irq-armada-370-xp.c
@@ -232,16 +232,12 @@ static int armada_370_xp_msi_alloc(struct irq_domain *domain, unsigned int virq,
 	int hwirq, i;
 
 	mutex_lock(&msi_used_lock);
+	hwirq = bitmap_find_free_region(msi_used, PCI_MSI_DOORBELL_NR,
+					order_base_2(nr_irqs));
+	mutex_unlock(&msi_used_lock);
 
-	hwirq = bitmap_find_next_zero_area(msi_used, PCI_MSI_DOORBELL_NR,
-					   0, nr_irqs, 0);
-	if (hwirq >= PCI_MSI_DOORBELL_NR) {
-		mutex_unlock(&msi_used_lock);
+	if (hwirq < 0)
 		return -ENOSPC;
-	}
-
-	bitmap_set(msi_used, hwirq, nr_irqs);
-	mutex_unlock(&msi_used_lock);
 
 	for (i = 0; i < nr_irqs; i++) {
 		irq_domain_set_info(domain, virq + i, hwirq + i,
@@ -259,7 +255,7 @@ static void armada_370_xp_msi_free(struct irq_domain *domain,
 	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
 
 	mutex_lock(&msi_used_lock);
-	bitmap_clear(msi_used, d->hwirq, nr_irqs);
+	bitmap_release_region(msi_used, d->hwirq, order_base_2(nr_irqs));
 	mutex_unlock(&msi_used_lock);
 }
 
-- 
2.20.1