[PATCH v3 0/2] irqchip: gic-v3: fix unmet dependency on ARM_PSCI_FW

[PATCH v3 0/2] irqchip: gic-v3: fix unmet dependency on ARM_PSCI_FW

[Julian Braha]

ARM_GIC_V3 currently selects HAVE_ARM_SMCCC_DISCOVERY without ensuring its
dependency, ARM_PSCI_FW, is met.

Patch 1 of this series makes the select conditional on arm64, and patch 2
adds stubs for arm32.

---
Julian Braha (2):
  irqchip: gic-v3: fix unmet dependency on ARM_PSCI_FW
  firmware: smccc: provide stubs when discovery is disabled

 drivers/irqchip/Kconfig   | 2 +-
 include/linux/arm-smccc.h | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

-- 
2.55.0

[PATCH v3 1/2] irqchip: gic-v3: only select HAVE_ARM_SMCCC_DISCOVERY on arm64

[Julian Braha]

ARM_PSCI_FW is always enabled for arm64, and the GICv3 driver only
uses HAVE_ARM_SMCCC_DISCOVERY to identify the NVIDIA T241, which is
arm64 anyway.

For ARM_GIC_V3, let's only select HAVE_ARM_SMCCC_DISCOVERY on arm64.

Fixes: 35727af2b15d ("irqchip/gicv3: Workaround for NVIDIA erratum T241-FABRIC-4")
Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Julian Braha <julianbraha@gmail.com>
---
Changes since v2:
- split out changes into two patches

Link to v2:
https://lore.kernel.org/all/20260823180832.1246363-1-julianbraha@gmail.com/

Changes since v1:
- remove select and dependency on ARM_PSCI_FW,
- make the HAVE_ARM_SMCCC_DISCOVERY 'select' conditional on arm64

Link to v1: https://lore.kernel.org/all/20260801212235.2692694-1-julianbraha@gmail.com/
---
 drivers/irqchip/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index a8f8c423b795..31b7e4c90007 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -37,7 +37,7 @@ config ARM_GIC_V3
 	bool
 	select IRQ_DOMAIN_HIERARCHY
 	select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
-	select HAVE_ARM_SMCCC_DISCOVERY
+	select HAVE_ARM_SMCCC_DISCOVERY if ARM64
 	select IRQ_MSI_IOMMU
 
 config ARM_GIC_ITS_PARENT
-- 
2.55.0

[PATCH v3 2/2] firmware: smccc: provide stubs when discovery is disabled

[Julian Braha]

Add fallbacks for callers to avoid needing #ifdef guards when
HAVE_ARM_SMCCC_DISCOVERY is disabled (32-bit arm).

Fixes: 35727af2b15d ("irqchip/gicv3: Workaround for NVIDIA erratum T241-FABRIC-4")
Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Julian Braha <julianbraha@gmail.com>
---
Changes since v2:
- split out changes into two patches

Link to v2:
https://lore.kernel.org/all/20260823180832.1246363-1-julianbraha@gmail.com/

Changes since v1:
- remove select and dependency on ARM_PSCI_FW,
- make the HAVE_ARM_SMCCC_DISCOVERY 'select' conditional on arm64

Link to v1: https://lore.kernel.org/all/20260801212235.2692694-1-julianbraha@gmail.com/
---
 include/linux/arm-smccc.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
index 4de81848fe2e..75f9d3f1723b 100644
--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -324,6 +324,7 @@ enum arm_smccc_conduit {
 	SMCCC_CONDUIT_HVC,
 };
 
+#ifdef CONFIG_HAVE_ARM_SMCCC_DISCOVERY
 /**
  * arm_smccc_1_1_get_conduit()
  *
@@ -363,6 +364,12 @@ s32 arm_smccc_get_soc_id_version(void);
  * When ARM_SMCCC_ARCH_SOC_ID is not present, returns SMCCC_RET_NOT_SUPPORTED.
  */
 s32 arm_smccc_get_soc_id_revision(void);
+#else   /* CONFIG_HAVE_ARM_SMCCC_DISCOVERY */
+#define arm_smccc_1_1_get_conduit()	SMCCC_CONDUIT_NONE
+#define arm_smccc_get_version()		0
+#define arm_smccc_get_soc_id_version()	SMCCC_RET_NOT_SUPPORTED
+#define arm_smccc_get_soc_id_revision()	SMCCC_RET_NOT_SUPPORTED
+#endif	/* CONFIG_HAVE_ARM_SMCCC_DISCOVERY */
 
 #ifndef __ASSEMBLY__
 
-- 
2.55.0

Re: [PATCH v3 0/2] irqchip: gic-v3: fix unmet dependency on ARM_PSCI_FW

[Marc Zyngier]

On Wed, 14 Oct 2026 13:35:37 +0100,
Julian Braha <julianbraha@gmail.com> wrote:
> 
> ARM_GIC_V3 currently selects HAVE_ARM_SMCCC_DISCOVERY without ensuring its
> dependency, ARM_PSCI_FW, is met.
> 
> Patch 1 of this series makes the select conditional on arm64, and patch 2
> adds stubs for arm32.
> 
> ---
> Julian Braha (2):
>   irqchip: gic-v3: fix unmet dependency on ARM_PSCI_FW
>   firmware: smccc: provide stubs when discovery is disabled
> 
>  drivers/irqchip/Kconfig   | 2 +-
>  include/linux/arm-smccc.h | 7 +++++++
>  2 files changed, 8 insertions(+), 1 deletion(-)

This hasn't been correctly tested, I'm afraid.

The patches are in the wrong order, as applying patch #1 on its own
will break a 32bit ARM build without PSCI (HAVE_ARM_SMCCC_DISCOVERY
not selected, but the stubs that are supposed to save the day are in
patch #2...):

arm-linux-gnueabihf-ld: drivers/irqchip/irq-gic-v3.o: in function `gic_enable_quirk_nvidia_t241':
/home/maz/hot-poop/arm-platforms/drivers/irqchip/irq-gic-v3.c:1816:(.text+0xb04): undefined reference to `arm_smccc_get_soc_id_version'
make[2]: *** [scripts/Makefile.vmlinux:72: vmlinux.unstripped] Error 1
make[1]: *** [/home/maz/hot-poop/arm-platforms/Makefile:1387: vmlinux] Error 2
make: *** [Makefile:248: __sub-make] Error 2

With the patch ordering fixed and the whole thing applied to the same
tree:

Reviewed-by: Marc Zyngier <maz@kernel.org>

	M.

-- 
Without deviation from the norm, progress is not possible.