[PATCH 1/3] arm: smmu: allow SMMU to have more IRQs than context banks

From: Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>
To: "xen-devel@lists.xenproject.org" <xen-devel@lists.xenproject.org>
Cc: Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>,
	Julien Grall <julien@xen.org>, Rahul Singh <rahul.singh@arm.com>,
	Stefano Stabellini <sstabellini@kernel.org>,
	Bertrand Marquis <bertrand.marquis@arm.com>,
	Michal Orzel <michal.orzel@amd.com>,
	Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>
Subject: [PATCH 1/3] arm: smmu: allow SMMU to have more IRQs than context banks
Date: Fri, 29 Mar 2024 00:08:57 +0000	[thread overview]
Message-ID: <20240329000822.3363568-2-volodymyr_babchuk@epam.com> (raw)
In-Reply-To: <20240329000822.3363568-1-volodymyr_babchuk@epam.com>

I encountered platform, namely Qualcomm SA8155P where SMMU-compatible
IO-MMU advertises more context IQRs than there are context banks. This
should not be an issue, we need to relax the check in the SMMU driver
to allow such configuration.

Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
---
 xen/drivers/passthrough/arm/smmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xen/drivers/passthrough/arm/smmu.c b/xen/drivers/passthrough/arm/smmu.c
index 32e2ff279b..2dd3688f3b 100644
--- a/xen/drivers/passthrough/arm/smmu.c
+++ b/xen/drivers/passthrough/arm/smmu.c
@@ -2550,7 +2550,7 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev)
 	parse_driver_options(smmu);
 
 	if (smmu->version > ARM_SMMU_V1 &&
-	    smmu->num_context_banks != smmu->num_context_irqs) {
+	    smmu->num_context_banks > smmu->num_context_irqs) {
 		dev_err(dev,
 			"found only %d context interrupt(s) but %d required\n",
 			smmu->num_context_irqs, smmu->num_context_banks);
-- 
2.43.0

