Add the SM6115 MDSS compatible to clients compatible list, as it also needs that workaround. Without this workaround, for example, QRB4210 RB2 which is based on SM4250/SM6115 generates a lot of smmu unhandled context faults during boot:

arm_smmu_context_fault: 116854 callbacks suppressed arm-smmu c600000.iommu: Unhandled context fault: fsr=0x402, iova=0x5c0ec600, fsynr=0x320021, cbfrsynra=0x420, cb=5 arm-smmu c600000.iommu: FSR = 00000402 [Format=2 TF], SID=0x420 arm-smmu c600000.iommu: FSYNR0 = 00320021 [S1CBNDX=50 PNU PLVL=1] arm-smmu c600000.iommu: Unhandled context fault: fsr=0x402, iova=0x5c0d7800, fsynr=0x320021, cbfrsynra=0x420, cb=5 arm-smmu c600000.iommu: FSR = 00000402 [Format=2 TF], SID=0x420

and also failed initialisation of lontium lt9611uxc, gpu and dpu is observed: (binding MDSS components triggered by lt9611uxc have failed)

------------[ cut here ]------------ !aspace WARNING: CPU: 6 PID: 324 at drivers/gpu/drm/msm/msm_gem_vma.c:130 msm_gem_vma_init+0x150/0x18c [msm] Modules linked in: ... (long list of modules) CPU: 6 UID: 0 PID: 324 Comm: (udev-worker) Not tainted 6.15.0-03037-gaacc73ceeb8b #4 PREEMPT Hardware name: Qualcomm Technologies, Inc. QRB4210 RB2 (DT) pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : msm_gem_vma_init+0x150/0x18c [msm] lr : msm_gem_vma_init+0x150/0x18c [msm] sp : ffff80008144b280 ... Call trace: msm_gem_vma_init+0x150/0x18c [msm] (P) get_vma_locked+0xc0/0x194 [msm] msm_gem_get_and_pin_iova_range+0x4c/0xdc [msm] msm_gem_kernel_new+0x48/0x160 [msm] msm_gpu_init+0x34c/0x53c [msm] adreno_gpu_init+0x1b0/0x2d8 [msm] a6xx_gpu_init+0x1e8/0x9e0 [msm] adreno_bind+0x2b8/0x348 [msm] component_bind_all+0x100/0x230 msm_drm_bind+0x13c/0x3d0 [msm] try_to_bring_up_aggregate_device+0x164/0x1d0 __component_add+0xa4/0x174 component_add+0x14/0x20 dsi_dev_attach+0x20/0x34 [msm] dsi_host_attach+0x58/0x98 [msm] devm_mipi_dsi_attach+0x34/0x90 lt9611uxc_attach_dsi.isra.0+0x94/0x124 [lontium_lt9611uxc] lt9611uxc_probe+0x540/0x5fc [lontium_lt9611uxc] i2c_device_probe+0x148/0x2a8 really_probe+0xbc/0x2c0 __driver_probe_device+0x78/0x120 driver_probe_device+0x3c/0x154 __driver_attach+0x90/0x1a0 bus_for_each_dev+0x68/0xb8 driver_attach+0x24/0x30 bus_add_driver+0xe4/0x208 driver_register+0x68/0x124 i2c_register_driver+0x48/0xcc lt9611uxc_driver_init+0x20/0x1000 [lontium_lt9611uxc] do_one_initcall+0x60/0x1d4 do_init_module+0x54/0x1fc load_module+0x1748/0x1c8c init_module_from_file+0x74/0xa0 __arm64_sys_finit_module+0x130/0x2f8 invoke_syscall+0x48/0x104 el0_svc_common.constprop.0+0xc0/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x2c/0x80 el0t_64_sync_handler+0x10c/0x138 el0t_64_sync+0x198/0x19c ---[ end trace 0000000000000000 ]--- msm_dpu 5e01000.display-controller: [drm:msm_gpu_init [msm]] *ERROR* could not allocate memptrs: -22 msm_dpu 5e01000.display-controller: failed to load adreno gpu platform a400000.remoteproc:glink-edge:apr:service@7:dais: Adding to iommu group 19 msm_dpu 5e01000.display-controller: failed to bind 5900000.gpu (ops a3xx_ops [msm]): -22 msm_dpu 5e01000.display-controller: adev bind failed: -22 lt9611uxc 0-002b: failed to attach dsi to host lt9611uxc 0-002b: probe with driver lt9611uxc failed with error -22

Suggested-by: Bjorn Andersson andersson@kernel.org Reviewed-by: Dmitry Baryshkov dmitry.baryshkov@oss.qualcomm.com Fixes: 3581b7062cec ("drm/msm/disp/dpu1: add support for display on SM6115") Cc: stable@vger.kernel.org Signed-off-by: Alexey Klimov alexey.klimov@linaro.org ---

v2: - added tags as suggested by Dmitry; - slightly updated text in the commit message.

Previous version: https://lore.kernel.org/linux-arm-msm/20250528003118.214093-1-alexey.klimov@...

drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c index 62874b18f645..c75023718595 100644 --- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c @@ -379,6 +379,7 @@ static const struct of_device_id qcom_smmu_client_of_match[] __maybe_unused = { { .compatible = "qcom,sdm670-mdss" }, { .compatible = "qcom,sdm845-mdss" }, { .compatible = "qcom,sdm845-mss-pil" }, + { .compatible = "qcom,sm6115-mdss" }, { .compatible = "qcom,sm6350-mdss" }, { .compatible = "qcom,sm6375-mdss" }, { .compatible = "qcom,sm8150-mdss" },