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authorFuad Tabba <fuad.tabba@linux.dev>2026-09-22 19:14:30 +0100
committerWill Deacon <will@kernel.org>2026-09-23 12:34:30 +0000
commit2bc6b218717b9d08f466f88209251d54bc09b207 (patch)
treecb91c941eccb15f94cbec4e96aa3a9c8736b5d66 /Documentation/PCI/endpoint/function
downloadlinux-stable-2bc6b218717b9d08f466f88209251d54bc09b207.tar.gz
linux-stable-2bc6b218717b9d08f466f88209251d54bc09b207.zip
arm64/boot: Disable trapping of PMZR_EL0 writes to EL2grafted
__init_el2_fgt2() writes one mask to both HDFGRTR2_EL2 and HDFGWTR2_EL2. PMZR_EL0 is write-only, so its trap bit, nPMZR_EL0, exists only in HDFGWTR2_EL2 and is therefore never set: a PMZR_EL0 write from the host traps to EL2, where the nVHE hypervisor has no handler and BUG()s. The kernel never writes PMZR_EL0, but kernel.perf_user_access=1 has the PMU driver set PMUSERENR_EL0.UEN for a task with a user-read event, so a write from EL0 reaches the trap and takes the host down without a panic message. Accumulate the HDFGWTR2_EL2 bits separately, as __init_el2_fgt() already does for HDFGWTR_EL2, and set nPMZR_EL0 with the other FEAT_PMUv3p9 bits. Fixes: 858c7bfcb35e1 ("arm64/boot: Enable EL2 requirements for FEAT_PMUv3p9") Cc: stable@vger.kernel.org Signed-off-by: Fuad Tabba <fuad.tabba@linux.dev> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Oliver Upton <oupton@kernel.org> Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'Documentation/PCI/endpoint/function')
-rw-r--r--Documentation/PCI/endpoint/function/binding/pci-ntb.rst38
-rw-r--r--Documentation/PCI/endpoint/function/binding/pci-test.rst26
2 files changed, 64 insertions, 0 deletions
diff --git a/Documentation/PCI/endpoint/function/binding/pci-ntb.rst b/Documentation/PCI/endpoint/function/binding/pci-ntb.rst
new file mode 100644
index 000000000..40253d3d5
--- /dev/null
+++ b/Documentation/PCI/endpoint/function/binding/pci-ntb.rst
@@ -0,0 +1,38 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+==========================
+PCI NTB Endpoint Function
+==========================
+
+1) Create a subdirectory to pci_epf_ntb directory in configfs.
+
+Standard EPF Configurable Fields:
+
+================ ===========================================================
+vendorid should be 0x104c
+deviceid should be 0xb00d for TI's J721E SoC
+revid don't care
+progif_code don't care
+subclass_code should be 0x00
+baseclass_code should be 0x5
+cache_line_size don't care
+subsys_vendor_id don't care
+subsys_id don't care
+interrupt_pin don't care
+msi_interrupts don't care
+msix_interrupts don't care
+================ ===========================================================
+
+2) Create a subdirectory to directory created in 1
+
+NTB EPF specific configurable fields:
+
+================ ===========================================================
+db_count Number of doorbells; default = 4
+mw1 size of memory window1
+mw2 size of memory window2
+mw3 size of memory window3
+mw4 size of memory window4
+num_mws Number of memory windows; max = 4
+spad_count Number of scratchpad registers; default = 64
+================ ===========================================================
diff --git a/Documentation/PCI/endpoint/function/binding/pci-test.rst b/Documentation/PCI/endpoint/function/binding/pci-test.rst
new file mode 100644
index 000000000..57ee866fb
--- /dev/null
+++ b/Documentation/PCI/endpoint/function/binding/pci-test.rst
@@ -0,0 +1,26 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+==========================
+PCI Test Endpoint Function
+==========================
+
+name: Should be "pci_epf_test" to bind to the pci_epf_test driver.
+
+Configurable Fields:
+
+================ ===========================================================
+vendorid should be 0x104c
+deviceid should be 0xb500 for DRA74x and 0xb501 for DRA72x
+revid don't care
+progif_code don't care
+subclass_code don't care
+baseclass_code should be 0xff
+cache_line_size don't care
+subsys_vendor_id don't care
+subsys_id don't care
+interrupt_pin Should be 1 - INTA, 2 - INTB, 3 - INTC, 4 -INTD
+msi_interrupts Should be 1 to 32 depending on the number of MSI interrupts
+ to test
+msix_interrupts Should be 1 to 2048 depending on the number of MSI-X
+ interrupts to test
+================ ===========================================================