Add device tree support to the CMDQV driver to enable usage on Tegra264
SoCs. The implementation parses the nvidia,cmdqv phandle from the SMMU
device tree node to associate each SMMU with its corresponding CMDQV
instance based on compatible string.
Remove the dependency from Kconfig as the driver now supports both ACPI
and device tree initialization through conditional compilation and
ARM_SMMU_V3 depends on ARM64 which implies at least OF.
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Ashish Mhetre <amhetre@nvidia.com>
---
drivers/iommu/arm/Kconfig | 1 -
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 32 +++++++++++++++++++
.../iommu/arm/arm-smmu-v3/tegra241-cmdqv.c | 27 +++++++++++++++-
3 files changed, 58 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/arm/Kconfig b/drivers/iommu/arm/Kconfig
index ef42bbe07dbe..5fac08b89dee 100644
--- a/drivers/iommu/arm/Kconfig
+++ b/drivers/iommu/arm/Kconfig
@@ -121,7 +121,6 @@ config ARM_SMMU_V3_KUNIT_TEST
config TEGRA241_CMDQV
bool "NVIDIA Tegra241 CMDQ-V extension support for ARM SMMUv3"
- depends on ACPI
help
Support for NVIDIA CMDQ-Virtualization extension for ARM SMMUv3. The
CMDQ-V extension is similar to v3.3 ECMDQ for multi command queues
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index d16d35c78c06..9433cd91c68f 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -4530,6 +4530,35 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
return 0;
}
+#ifdef CONFIG_TEGRA241_CMDQV
+static void tegra_cmdqv_dt_probe(struct device_node *smmu_node,
+ struct arm_smmu_device *smmu)
+{
+ struct platform_device *pdev;
+ struct device_node *np;
+
+ np = of_parse_phandle(smmu_node, "nvidia,cmdqv", 0);
+ if (!np)
+ return;
+
+ pdev = of_find_device_by_node(np);
+ of_node_put(np);
+ if (!pdev)
+ return;
+
+ smmu->impl_dev = &pdev->dev;
+ smmu->options |= ARM_SMMU_OPT_TEGRA241_CMDQV;
+ dev_info(smmu->dev, "found companion CMDQV device: %s\n",
+ dev_name(smmu->impl_dev));
+ put_device(&pdev->dev);
+}
+#else
+static void tegra_cmdqv_dt_probe(struct device_node *smmu_node,
+ struct arm_smmu_device *smmu)
+{
+}
+#endif
+
#ifdef CONFIG_ACPI
#ifdef CONFIG_TEGRA241_CMDQV
static void acpi_smmu_dsdt_probe_tegra241_cmdqv(struct acpi_iort_node *node,
@@ -4634,6 +4663,9 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev,
if (of_dma_is_coherent(dev->of_node))
smmu->features |= ARM_SMMU_FEAT_COHERENCY;
+ if (of_device_is_compatible(dev->of_node, "nvidia,tegra264-smmu"))
+ tegra_cmdqv_dt_probe(dev->of_node, smmu);
+
return ret;
}
diff --git a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
index 378104cd395e..c096c8229c5d 100644
--- a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
+++ b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
@@ -11,6 +11,8 @@
#include <linux/iommufd.h>
#include <linux/iopoll.h>
#include <uapi/linux/iommufd.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
#include <acpi/acpixf.h>
@@ -917,6 +919,26 @@ tegra241_cmdqv_find_acpi_resource(struct device *dev, int *irq)
return res;
}
+static struct resource *
+tegra241_cmdqv_find_dt_resource(struct device *dev, int *irq)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct resource *res;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(dev, "no memory resource found for CMDQV\n");
+ return NULL;
+ }
+
+ if (irq)
+ *irq = platform_get_irq_optional(pdev, 0);
+ if (!irq || *irq <= 0)
+ dev_warn(dev, "no interrupt. errors will not be reported\n");
+
+ return res;
+}
+
static int tegra241_cmdqv_init_structures(struct arm_smmu_device *smmu)
{
struct tegra241_cmdqv *cmdqv =
@@ -1048,11 +1070,14 @@ struct arm_smmu_device *tegra241_cmdqv_probe(struct arm_smmu_device *smmu)
if (!smmu->dev->of_node)
res = tegra241_cmdqv_find_acpi_resource(smmu->impl_dev, &irq);
+ else
+ res = tegra241_cmdqv_find_dt_resource(smmu->impl_dev, &irq);
if (!res)
goto out_fallback;
new_smmu = __tegra241_cmdqv_probe(smmu, res, irq);
- kfree(res);
+ if (!smmu->dev->of_node)
+ kfree(res);
if (new_smmu)
return new_smmu;
--
2.25.1Hi Ashish,
kernel test robot noticed the following build warnings:
[auto build test WARNING on next-20251204]
[also build test WARNING on v6.18]
[cannot apply to robh/for-next linus/master v6.18 v6.18-rc7 v6.18-rc6]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Ashish-Mhetre/iommu-arm-smmu-v3-Add-device-tree-support-for-CMDQV-driver/20251205-151258
base: next-20251204
patch link: https://lore.kernel.org/r/20251205065850.3841834-2-amhetre%40nvidia.com
patch subject: [PATCH V4 1/3] iommu/arm-smmu-v3: Add device-tree support for CMDQV driver
config: arm64-randconfig-004-20251209 (https://download.01.org/0day-ci/archive/20251209/202512090331.QAFgb6vQ-lkp@intel.com/config)
compiler: aarch64-linux-gcc (GCC) 11.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251209/202512090331.QAFgb6vQ-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202512090331.QAFgb6vQ-lkp@intel.com/
All warnings (new ones prefixed by >>):
drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c: In function 'tegra241_cmdqv_acpi_is_memory':
drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c:863:17: error: implicit declaration of function 'acpi_dev_resource_address_space' [-Werror=implicit-function-declaration]
863 | return !acpi_dev_resource_address_space(res, &win);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c: In function 'tegra241_cmdqv_acpi_get_irqs':
drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c:871:26: error: implicit declaration of function 'acpi_dev_resource_interrupt' [-Werror=implicit-function-declaration]
871 | if (*irq <= 0 && acpi_dev_resource_interrupt(ares, 0, &r))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c: In function 'tegra241_cmdqv_find_acpi_resource':
drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c:879:36: error: implicit declaration of function 'to_acpi_device'; did you mean 'to_acpi_device_node'? [-Werror=implicit-function-declaration]
879 | struct acpi_device *adev = to_acpi_device(dev);
| ^~~~~~~~~~~~~~
| to_acpi_device_node
>> drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c:879:36: warning: initialization of 'struct acpi_device *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c:886:15: error: implicit declaration of function 'acpi_dev_get_resources'; did you mean 'acpi_get_event_resources'? [-Werror=implicit-function-declaration]
886 | ret = acpi_dev_get_resources(adev, &resource_list,
| ^~~~~~~~~~~~~~~~~~~~~~
| acpi_get_event_resources
drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c:907:9: error: implicit declaration of function 'acpi_dev_free_resource_list' [-Werror=implicit-function-declaration]
907 | acpi_dev_free_resource_list(&resource_list);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors
vim +879 drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
918eb5c856f6ce Nate Watterson 2024-08-29 875
918eb5c856f6ce Nate Watterson 2024-08-29 876 static struct resource *
918eb5c856f6ce Nate Watterson 2024-08-29 877 tegra241_cmdqv_find_acpi_resource(struct device *dev, int *irq)
918eb5c856f6ce Nate Watterson 2024-08-29 878 {
918eb5c856f6ce Nate Watterson 2024-08-29 @879 struct acpi_device *adev = to_acpi_device(dev);
918eb5c856f6ce Nate Watterson 2024-08-29 880 struct list_head resource_list;
918eb5c856f6ce Nate Watterson 2024-08-29 881 struct resource_entry *rentry;
918eb5c856f6ce Nate Watterson 2024-08-29 882 struct resource *res = NULL;
918eb5c856f6ce Nate Watterson 2024-08-29 883 int ret;
918eb5c856f6ce Nate Watterson 2024-08-29 884
918eb5c856f6ce Nate Watterson 2024-08-29 885 INIT_LIST_HEAD(&resource_list);
918eb5c856f6ce Nate Watterson 2024-08-29 886 ret = acpi_dev_get_resources(adev, &resource_list,
918eb5c856f6ce Nate Watterson 2024-08-29 887 tegra241_cmdqv_acpi_is_memory, NULL);
918eb5c856f6ce Nate Watterson 2024-08-29 888 if (ret < 0) {
918eb5c856f6ce Nate Watterson 2024-08-29 889 dev_err(dev, "failed to get memory resource: %d\n", ret);
918eb5c856f6ce Nate Watterson 2024-08-29 890 return NULL;
918eb5c856f6ce Nate Watterson 2024-08-29 891 }
918eb5c856f6ce Nate Watterson 2024-08-29 892
918eb5c856f6ce Nate Watterson 2024-08-29 893 rentry = list_first_entry_or_null(&resource_list,
918eb5c856f6ce Nate Watterson 2024-08-29 894 struct resource_entry, node);
918eb5c856f6ce Nate Watterson 2024-08-29 895 if (!rentry) {
918eb5c856f6ce Nate Watterson 2024-08-29 896 dev_err(dev, "failed to get memory resource entry\n");
918eb5c856f6ce Nate Watterson 2024-08-29 897 goto free_list;
918eb5c856f6ce Nate Watterson 2024-08-29 898 }
918eb5c856f6ce Nate Watterson 2024-08-29 899
918eb5c856f6ce Nate Watterson 2024-08-29 900 /* Caller must free the res */
918eb5c856f6ce Nate Watterson 2024-08-29 901 res = kzalloc(sizeof(*res), GFP_KERNEL);
918eb5c856f6ce Nate Watterson 2024-08-29 902 if (!res)
918eb5c856f6ce Nate Watterson 2024-08-29 903 goto free_list;
918eb5c856f6ce Nate Watterson 2024-08-29 904
918eb5c856f6ce Nate Watterson 2024-08-29 905 *res = *rentry->res;
918eb5c856f6ce Nate Watterson 2024-08-29 906
918eb5c856f6ce Nate Watterson 2024-08-29 907 acpi_dev_free_resource_list(&resource_list);
918eb5c856f6ce Nate Watterson 2024-08-29 908
918eb5c856f6ce Nate Watterson 2024-08-29 909 INIT_LIST_HEAD(&resource_list);
918eb5c856f6ce Nate Watterson 2024-08-29 910
918eb5c856f6ce Nate Watterson 2024-08-29 911 if (irq)
918eb5c856f6ce Nate Watterson 2024-08-29 912 ret = acpi_dev_get_resources(adev, &resource_list,
918eb5c856f6ce Nate Watterson 2024-08-29 913 tegra241_cmdqv_acpi_get_irqs, irq);
918eb5c856f6ce Nate Watterson 2024-08-29 914 if (ret < 0 || !irq || *irq <= 0)
918eb5c856f6ce Nate Watterson 2024-08-29 915 dev_warn(dev, "no interrupt. errors will not be reported\n");
918eb5c856f6ce Nate Watterson 2024-08-29 916
918eb5c856f6ce Nate Watterson 2024-08-29 917 free_list:
918eb5c856f6ce Nate Watterson 2024-08-29 918 acpi_dev_free_resource_list(&resource_list);
918eb5c856f6ce Nate Watterson 2024-08-29 919 return res;
918eb5c856f6ce Nate Watterson 2024-08-29 920 }
918eb5c856f6ce Nate Watterson 2024-08-29 921
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
On 12/9/2025 1:13 AM, kernel test robot wrote:
> External email: Use caution opening links or attachments
>
>
> Hi Ashish,
>
> kernel test robot noticed the following build warnings:
>
> [auto build test WARNING on next-20251204]
> [also build test WARNING on v6.18]
> [cannot apply to robh/for-next linus/master v6.18 v6.18-rc7 v6.18-rc6]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch#_base_tree_information]
>
> url: https://github.com/intel-lab-lkp/linux/commits/Ashish-Mhetre/iommu-arm-smmu-v3-Add-device-tree-support-for-CMDQV-driver/20251205-151258
> base: next-20251204
> patch link: https://lore.kernel.org/r/20251205065850.3841834-2-amhetre%40nvidia.com
> patch subject: [PATCH V4 1/3] iommu/arm-smmu-v3: Add device-tree support for CMDQV driver
> config: arm64-randconfig-004-20251209 (https://download.01.org/0day-ci/archive/20251209/202512090331.QAFgb6vQ-lkp@intel.com/config)
> compiler: aarch64-linux-gcc (GCC) 11.5.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251209/202512090331.QAFgb6vQ-lkp@intel.com/reproduce)
>
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202512090331.QAFgb6vQ-lkp@intel.com/
>
> All warnings (new ones prefixed by >>):
>
> drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c: In function 'tegra241_cmdqv_acpi_is_memory':
> drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c:863:17: error: implicit declaration of function 'acpi_dev_resource_address_space' [-Werror=implicit-function-declaration]
> 863 | return !acpi_dev_resource_address_space(res, &win);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c: In function 'tegra241_cmdqv_acpi_get_irqs':
> drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c:871:26: error: implicit declaration of function 'acpi_dev_resource_interrupt' [-Werror=implicit-function-declaration]
> 871 | if (*irq <= 0 && acpi_dev_resource_interrupt(ares, 0, &r))
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c: In function 'tegra241_cmdqv_find_acpi_resource':
> drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c:879:36: error: implicit declaration of function 'to_acpi_device'; did you mean 'to_acpi_device_node'? [-Werror=implicit-function-declaration]
> 879 | struct acpi_device *adev = to_acpi_device(dev);
> | ^~~~~~~~~~~~~~
> | to_acpi_device_node
>>> drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c:879:36: warning: initialization of 'struct acpi_device *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
> drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c:886:15: error: implicit declaration of function 'acpi_dev_get_resources'; did you mean 'acpi_get_event_resources'? [-Werror=implicit-function-declaration]
> 886 | ret = acpi_dev_get_resources(adev, &resource_list,
> | ^~~~~~~~~~~~~~~~~~~~~~
> | acpi_get_event_resources
> drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c:907:9: error: implicit declaration of function 'acpi_dev_free_resource_list' [-Werror=implicit-function-declaration]
> 907 | acpi_dev_free_resource_list(&resource_list);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~
> cc1: some warnings being treated as errors
Hi Robin, Nic,
We removed ACPI dependency in Kconfig but driver still depends
on ACPI for these functions. I will be protecting ACPIspecific
tegra241-cmdqv code under CONFIG_ACPI similar to what is done
in arm-smmu-v3 driver. Is this the correct thing to do or do you
have any other suggestions?
> vim +879 drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
>
> 918eb5c856f6ce Nate Watterson 2024-08-29 875
> 918eb5c856f6ce Nate Watterson 2024-08-29 876 static struct resource *
> 918eb5c856f6ce Nate Watterson 2024-08-29 877 tegra241_cmdqv_find_acpi_resource(struct device *dev, int *irq)
> 918eb5c856f6ce Nate Watterson 2024-08-29 878 {
> 918eb5c856f6ce Nate Watterson 2024-08-29 @879 struct acpi_device *adev = to_acpi_device(dev);
> 918eb5c856f6ce Nate Watterson 2024-08-29 880 struct list_head resource_list;
> 918eb5c856f6ce Nate Watterson 2024-08-29 881 struct resource_entry *rentry;
> 918eb5c856f6ce Nate Watterson 2024-08-29 882 struct resource *res = NULL;
> 918eb5c856f6ce Nate Watterson 2024-08-29 883 int ret;
> 918eb5c856f6ce Nate Watterson 2024-08-29 884
> 918eb5c856f6ce Nate Watterson 2024-08-29 885 INIT_LIST_HEAD(&resource_list);
> 918eb5c856f6ce Nate Watterson 2024-08-29 886 ret = acpi_dev_get_resources(adev, &resource_list,
> 918eb5c856f6ce Nate Watterson 2024-08-29 887 tegra241_cmdqv_acpi_is_memory, NULL);
> 918eb5c856f6ce Nate Watterson 2024-08-29 888 if (ret < 0) {
> 918eb5c856f6ce Nate Watterson 2024-08-29 889 dev_err(dev, "failed to get memory resource: %d\n", ret);
> 918eb5c856f6ce Nate Watterson 2024-08-29 890 return NULL;
> 918eb5c856f6ce Nate Watterson 2024-08-29 891 }
> 918eb5c856f6ce Nate Watterson 2024-08-29 892
> 918eb5c856f6ce Nate Watterson 2024-08-29 893 rentry = list_first_entry_or_null(&resource_list,
> 918eb5c856f6ce Nate Watterson 2024-08-29 894 struct resource_entry, node);
> 918eb5c856f6ce Nate Watterson 2024-08-29 895 if (!rentry) {
> 918eb5c856f6ce Nate Watterson 2024-08-29 896 dev_err(dev, "failed to get memory resource entry\n");
> 918eb5c856f6ce Nate Watterson 2024-08-29 897 goto free_list;
> 918eb5c856f6ce Nate Watterson 2024-08-29 898 }
> 918eb5c856f6ce Nate Watterson 2024-08-29 899
> 918eb5c856f6ce Nate Watterson 2024-08-29 900 /* Caller must free the res */
> 918eb5c856f6ce Nate Watterson 2024-08-29 901 res = kzalloc(sizeof(*res), GFP_KERNEL);
> 918eb5c856f6ce Nate Watterson 2024-08-29 902 if (!res)
> 918eb5c856f6ce Nate Watterson 2024-08-29 903 goto free_list;
> 918eb5c856f6ce Nate Watterson 2024-08-29 904
> 918eb5c856f6ce Nate Watterson 2024-08-29 905 *res = *rentry->res;
> 918eb5c856f6ce Nate Watterson 2024-08-29 906
> 918eb5c856f6ce Nate Watterson 2024-08-29 907 acpi_dev_free_resource_list(&resource_list);
> 918eb5c856f6ce Nate Watterson 2024-08-29 908
> 918eb5c856f6ce Nate Watterson 2024-08-29 909 INIT_LIST_HEAD(&resource_list);
> 918eb5c856f6ce Nate Watterson 2024-08-29 910
> 918eb5c856f6ce Nate Watterson 2024-08-29 911 if (irq)
> 918eb5c856f6ce Nate Watterson 2024-08-29 912 ret = acpi_dev_get_resources(adev, &resource_list,
> 918eb5c856f6ce Nate Watterson 2024-08-29 913 tegra241_cmdqv_acpi_get_irqs, irq);
> 918eb5c856f6ce Nate Watterson 2024-08-29 914 if (ret < 0 || !irq || *irq <= 0)
> 918eb5c856f6ce Nate Watterson 2024-08-29 915 dev_warn(dev, "no interrupt. errors will not be reported\n");
> 918eb5c856f6ce Nate Watterson 2024-08-29 916
> 918eb5c856f6ce Nate Watterson 2024-08-29 917 free_list:
> 918eb5c856f6ce Nate Watterson 2024-08-29 918 acpi_dev_free_resource_list(&resource_list);
> 918eb5c856f6ce Nate Watterson 2024-08-29 919 return res;
> 918eb5c856f6ce Nate Watterson 2024-08-29 920 }
> 918eb5c856f6ce Nate Watterson 2024-08-29 921
>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki
On 2025-12-10 5:19 am, Ashish Mhetre wrote: [...] > Hi Robin, Nic, > We removed ACPI dependency in Kconfig but driver still depends > on ACPI for these functions. I will be protecting ACPIspecific > tegra241-cmdqv code under CONFIG_ACPI similar to what is done > in arm-smmu-v3 driver. Is this the correct thing to do or do you > have any other suggestions? Yes, when I commented that "depends on ACPI || OF" was functionally the same as just removing "depends on ACPI", I didn't mean to suggest that wasn't necessarily a genuine dependency still. I guess if you can wrap the ACPI-specific functions in a single #ifdef block that's reasonable, however I do now wonder whether things couldn't be factored out a bit more - if it's a standard DSDT/SSDT namespace device, shouldn't there also be a corresponding platform device created for it, which we could look up instead of delving directly into the _CRS of the ACPI node itself? (not sure off-hand if there's a straightforward inverse of ACPI_COMPANION()...) Thanks, Robin.
On Wed, Dec 10, 2025 at 12:39:49PM +0000, Robin Murphy wrote:
> On 2025-12-10 5:19 am, Ashish Mhetre wrote:
> [...]
> > Hi Robin, Nic,
> > We removed ACPI dependency in Kconfig but driver still depends
> > on ACPI for these functions. I will be protecting ACPIspecific
> > tegra241-cmdqv code under CONFIG_ACPI similar to what is done
> > in arm-smmu-v3 driver. Is this the correct thing to do or do you
> > have any other suggestions?
>
> Yes, when I commented that "depends on ACPI || OF" was functionally the same
> as just removing "depends on ACPI", I didn't mean to suggest that wasn't
> necessarily a genuine dependency still.
>
> I guess if you can wrap the ACPI-specific functions in a single #ifdef block
> that's reasonable, however I do now wonder whether things couldn't be
> factored out a bit more - if it's a standard DSDT/SSDT namespace device,
> shouldn't there also be a corresponding platform device created for it,
> which we could look up instead of delving directly into the _CRS of the ACPI
> node itself? (not sure off-hand if there's a straightforward inverse of
> ACPI_COMPANION()...)
Ah, I did a quick tracer at acpi_create_platform_device(). And I
do see platform devices being created. So, we could have made it
ACPI-independent from the beginning, as you expected :)
Ashish, let's attach the following patch in your series:
From 7b69a638276e66b16b923b0ce1743d3efc85a04c Mon Sep 17 00:00:00 2001
From: Nicolin Chen <nicolinc@nvidia.com>
Date: Thu, 11 Dec 2025 05:47:05 +0000
Subject: [PATCH] iommu/tegra241-cmdqv: Decouple driver from ACPI
A platform device is created by acpi_create_platform_device() per CMDQV's
adev. That means there is no point in going through _CRS of ACPI.
Replace all the ACPI functions with standard platform functions. And drop
all ACPI dependencies. This will make the driver compatible with DT also.
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
drivers/iommu/arm/Kconfig | 1 -
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 2 +-
.../iommu/arm/arm-smmu-v3/tegra241-cmdqv.c | 84 +++----------------
3 files changed, 13 insertions(+), 74 deletions(-)
diff --git a/drivers/iommu/arm/Kconfig b/drivers/iommu/arm/Kconfig
index ef42bbe07dbef..5fac08b89deea 100644
--- a/drivers/iommu/arm/Kconfig
+++ b/drivers/iommu/arm/Kconfig
@@ -121,7 +121,6 @@ config ARM_SMMU_V3_KUNIT_TEST
config TEGRA241_CMDQV
bool "NVIDIA Tegra241 CMDQ-V extension support for ARM SMMUv3"
- depends on ACPI
help
Support for NVIDIA CMDQ-Virtualization extension for ARM SMMUv3. The
CMDQ-V extension is similar to v3.3 ECMDQ for multi command queues
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 38028e4a52f7f..0c98be3135c63 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -5280,7 +5280,7 @@ static void acpi_smmu_dsdt_probe_tegra241_cmdqv(struct acpi_iort_node *node,
adev = acpi_dev_get_first_match_dev("NVDA200C", uid, -1);
if (adev) {
/* Tegra241 CMDQV driver is responsible for put_device() */
- smmu->impl_dev = &adev->dev;
+ smmu->impl_dev = acpi_get_first_physical_node(adev);
smmu->options |= ARM_SMMU_OPT_TEGRA241_CMDQV;
dev_info(smmu->dev, "found companion CMDQV device: %s\n",
dev_name(smmu->impl_dev));
diff --git a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
index 378104cd395e5..1fc03b72beb88 100644
--- a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
+++ b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
@@ -3,17 +3,15 @@
#define dev_fmt(fmt) "tegra241_cmdqv: " fmt
-#include <linux/acpi.h>
#include <linux/debugfs.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/iommu.h>
#include <linux/iommufd.h>
#include <linux/iopoll.h>
+#include <linux/platform_device.h>
#include <uapi/linux/iommufd.h>
-#include <acpi/acpixf.h>
-
#include "arm-smmu-v3.h"
/* CMDQV register page base and size defines */
@@ -854,69 +852,6 @@ static struct arm_smmu_impl_ops tegra241_cmdqv_impl_ops = {
/* Probe Functions */
-static int tegra241_cmdqv_acpi_is_memory(struct acpi_resource *res, void *data)
-{
- struct resource_win win;
-
- return !acpi_dev_resource_address_space(res, &win);
-}
-
-static int tegra241_cmdqv_acpi_get_irqs(struct acpi_resource *ares, void *data)
-{
- struct resource r;
- int *irq = data;
-
- if (*irq <= 0 && acpi_dev_resource_interrupt(ares, 0, &r))
- *irq = r.start;
- return 1; /* No need to add resource to the list */
-}
-
-static struct resource *
-tegra241_cmdqv_find_acpi_resource(struct device *dev, int *irq)
-{
- struct acpi_device *adev = to_acpi_device(dev);
- struct list_head resource_list;
- struct resource_entry *rentry;
- struct resource *res = NULL;
- int ret;
-
- INIT_LIST_HEAD(&resource_list);
- ret = acpi_dev_get_resources(adev, &resource_list,
- tegra241_cmdqv_acpi_is_memory, NULL);
- if (ret < 0) {
- dev_err(dev, "failed to get memory resource: %d\n", ret);
- return NULL;
- }
-
- rentry = list_first_entry_or_null(&resource_list,
- struct resource_entry, node);
- if (!rentry) {
- dev_err(dev, "failed to get memory resource entry\n");
- goto free_list;
- }
-
- /* Caller must free the res */
- res = kzalloc(sizeof(*res), GFP_KERNEL);
- if (!res)
- goto free_list;
-
- *res = *rentry->res;
-
- acpi_dev_free_resource_list(&resource_list);
-
- INIT_LIST_HEAD(&resource_list);
-
- if (irq)
- ret = acpi_dev_get_resources(adev, &resource_list,
- tegra241_cmdqv_acpi_get_irqs, irq);
- if (ret < 0 || !irq || *irq <= 0)
- dev_warn(dev, "no interrupt. errors will not be reported\n");
-
-free_list:
- acpi_dev_free_resource_list(&resource_list);
- return res;
-}
-
static int tegra241_cmdqv_init_structures(struct arm_smmu_device *smmu)
{
struct tegra241_cmdqv *cmdqv =
@@ -1042,18 +977,23 @@ __tegra241_cmdqv_probe(struct arm_smmu_device *smmu, struct resource *res,
struct arm_smmu_device *tegra241_cmdqv_probe(struct arm_smmu_device *smmu)
{
+ struct platform_device *pdev = to_platform_device(smmu->impl_dev);
struct arm_smmu_device *new_smmu;
- struct resource *res = NULL;
+ struct resource *res;
int irq;
- if (!smmu->dev->of_node)
- res = tegra241_cmdqv_find_acpi_resource(smmu->impl_dev, &irq);
- if (!res)
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "no memory resource found for CMDQV\n");
goto out_fallback;
+ }
- new_smmu = __tegra241_cmdqv_probe(smmu, res, irq);
- kfree(res);
+ irq = platform_get_irq_optional(pdev, 0);
+ if (irq <= 0)
+ dev_warn(&pdev->dev,
+ "no interrupt. errors will not be reported\n");
+ new_smmu = __tegra241_cmdqv_probe(smmu, res, irq);
if (new_smmu)
return new_smmu;
--
2.43.0
On 12/11/2025 11:39 AM, Nicolin Chen wrote:
> On Wed, Dec 10, 2025 at 12:39:49PM +0000, Robin Murphy wrote:
>> On 2025-12-10 5:19 am, Ashish Mhetre wrote:
>> [...]
>>> Hi Robin, Nic,
>>> We removed ACPI dependency in Kconfig but driver still depends
>>> on ACPI for these functions. I will be protecting ACPIspecific
>>> tegra241-cmdqv code under CONFIG_ACPI similar to what is done
>>> in arm-smmu-v3 driver. Is this the correct thing to do or do you
>>> have any other suggestions?
>> Yes, when I commented that "depends on ACPI || OF" was functionally the same
>> as just removing "depends on ACPI", I didn't mean to suggest that wasn't
>> necessarily a genuine dependency still.
>>
>> I guess if you can wrap the ACPI-specific functions in a single #ifdef block
>> that's reasonable, however I do now wonder whether things couldn't be
>> factored out a bit more - if it's a standard DSDT/SSDT namespace device,
>> shouldn't there also be a corresponding platform device created for it,
>> which we could look up instead of delving directly into the _CRS of the ACPI
>> node itself? (not sure off-hand if there's a straightforward inverse of
>> ACPI_COMPANION()...)
> Ah, I did a quick tracer at acpi_create_platform_device(). And I
> do see platform devices being created. So, we could have made it
> ACPI-independent from the beginning, as you expected :)
>
> Ashish, let's attach the following patch in your series:
Ack, thanks Robin and Nic. I'll update my patches on top of Nic's patch
and re-post.
> From 7b69a638276e66b16b923b0ce1743d3efc85a04c Mon Sep 17 00:00:00 2001
> From: Nicolin Chen <nicolinc@nvidia.com>
> Date: Thu, 11 Dec 2025 05:47:05 +0000
> Subject: [PATCH] iommu/tegra241-cmdqv: Decouple driver from ACPI
>
> A platform device is created by acpi_create_platform_device() per CMDQV's
> adev. That means there is no point in going through _CRS of ACPI.
>
> Replace all the ACPI functions with standard platform functions. And drop
> all ACPI dependencies. This will make the driver compatible with DT also.
>
> Suggested-by: Robin Murphy <robin.murphy@arm.com>
> Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
> ---
> drivers/iommu/arm/Kconfig | 1 -
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 2 +-
> .../iommu/arm/arm-smmu-v3/tegra241-cmdqv.c | 84 +++----------------
> 3 files changed, 13 insertions(+), 74 deletions(-)
>
> diff --git a/drivers/iommu/arm/Kconfig b/drivers/iommu/arm/Kconfig
> index ef42bbe07dbef..5fac08b89deea 100644
> --- a/drivers/iommu/arm/Kconfig
> +++ b/drivers/iommu/arm/Kconfig
> @@ -121,7 +121,6 @@ config ARM_SMMU_V3_KUNIT_TEST
>
> config TEGRA241_CMDQV
> bool "NVIDIA Tegra241 CMDQ-V extension support for ARM SMMUv3"
> - depends on ACPI
> help
> Support for NVIDIA CMDQ-Virtualization extension for ARM SMMUv3. The
> CMDQ-V extension is similar to v3.3 ECMDQ for multi command queues
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> index 38028e4a52f7f..0c98be3135c63 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -5280,7 +5280,7 @@ static void acpi_smmu_dsdt_probe_tegra241_cmdqv(struct acpi_iort_node *node,
> adev = acpi_dev_get_first_match_dev("NVDA200C", uid, -1);
> if (adev) {
> /* Tegra241 CMDQV driver is responsible for put_device() */
> - smmu->impl_dev = &adev->dev;
> + smmu->impl_dev = acpi_get_first_physical_node(adev);
> smmu->options |= ARM_SMMU_OPT_TEGRA241_CMDQV;
> dev_info(smmu->dev, "found companion CMDQV device: %s\n",
> dev_name(smmu->impl_dev));
> diff --git a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
> index 378104cd395e5..1fc03b72beb88 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
> @@ -3,17 +3,15 @@
>
> #define dev_fmt(fmt) "tegra241_cmdqv: " fmt
>
> -#include <linux/acpi.h>
> #include <linux/debugfs.h>
> #include <linux/dma-mapping.h>
> #include <linux/interrupt.h>
> #include <linux/iommu.h>
> #include <linux/iommufd.h>
> #include <linux/iopoll.h>
> +#include <linux/platform_device.h>
> #include <uapi/linux/iommufd.h>
>
> -#include <acpi/acpixf.h>
> -
> #include "arm-smmu-v3.h"
>
> /* CMDQV register page base and size defines */
> @@ -854,69 +852,6 @@ static struct arm_smmu_impl_ops tegra241_cmdqv_impl_ops = {
>
> /* Probe Functions */
>
> -static int tegra241_cmdqv_acpi_is_memory(struct acpi_resource *res, void *data)
> -{
> - struct resource_win win;
> -
> - return !acpi_dev_resource_address_space(res, &win);
> -}
> -
> -static int tegra241_cmdqv_acpi_get_irqs(struct acpi_resource *ares, void *data)
> -{
> - struct resource r;
> - int *irq = data;
> -
> - if (*irq <= 0 && acpi_dev_resource_interrupt(ares, 0, &r))
> - *irq = r.start;
> - return 1; /* No need to add resource to the list */
> -}
> -
> -static struct resource *
> -tegra241_cmdqv_find_acpi_resource(struct device *dev, int *irq)
> -{
> - struct acpi_device *adev = to_acpi_device(dev);
> - struct list_head resource_list;
> - struct resource_entry *rentry;
> - struct resource *res = NULL;
> - int ret;
> -
> - INIT_LIST_HEAD(&resource_list);
> - ret = acpi_dev_get_resources(adev, &resource_list,
> - tegra241_cmdqv_acpi_is_memory, NULL);
> - if (ret < 0) {
> - dev_err(dev, "failed to get memory resource: %d\n", ret);
> - return NULL;
> - }
> -
> - rentry = list_first_entry_or_null(&resource_list,
> - struct resource_entry, node);
> - if (!rentry) {
> - dev_err(dev, "failed to get memory resource entry\n");
> - goto free_list;
> - }
> -
> - /* Caller must free the res */
> - res = kzalloc(sizeof(*res), GFP_KERNEL);
> - if (!res)
> - goto free_list;
> -
> - *res = *rentry->res;
> -
> - acpi_dev_free_resource_list(&resource_list);
> -
> - INIT_LIST_HEAD(&resource_list);
> -
> - if (irq)
> - ret = acpi_dev_get_resources(adev, &resource_list,
> - tegra241_cmdqv_acpi_get_irqs, irq);
> - if (ret < 0 || !irq || *irq <= 0)
> - dev_warn(dev, "no interrupt. errors will not be reported\n");
> -
> -free_list:
> - acpi_dev_free_resource_list(&resource_list);
> - return res;
> -}
> -
> static int tegra241_cmdqv_init_structures(struct arm_smmu_device *smmu)
> {
> struct tegra241_cmdqv *cmdqv =
> @@ -1042,18 +977,23 @@ __tegra241_cmdqv_probe(struct arm_smmu_device *smmu, struct resource *res,
>
> struct arm_smmu_device *tegra241_cmdqv_probe(struct arm_smmu_device *smmu)
> {
> + struct platform_device *pdev = to_platform_device(smmu->impl_dev);
> struct arm_smmu_device *new_smmu;
> - struct resource *res = NULL;
> + struct resource *res;
> int irq;
>
> - if (!smmu->dev->of_node)
> - res = tegra241_cmdqv_find_acpi_resource(smmu->impl_dev, &irq);
> - if (!res)
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!res) {
> + dev_err(&pdev->dev, "no memory resource found for CMDQV\n");
> goto out_fallback;
> + }
>
> - new_smmu = __tegra241_cmdqv_probe(smmu, res, irq);
> - kfree(res);
> + irq = platform_get_irq_optional(pdev, 0);
> + if (irq <= 0)
> + dev_warn(&pdev->dev,
> + "no interrupt. errors will not be reported\n");
>
> + new_smmu = __tegra241_cmdqv_probe(smmu, res, irq);
> if (new_smmu)
> return new_smmu;
>
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