From 0328947c50324cf4b2d8b181bf948edb8101f59f Mon Sep 17 00:00:00 2001 From: Manivannan Sadhasivam Date: Wed, 28 Aug 2024 21:16:15 +0530 Subject: PCI: endpoint: Assign PCI domain number for endpoint controllers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Right now, PCI endpoint subsystem doesn't assign PCI domain number for the PCI endpoint controllers. But this domain number could be useful to the EPC drivers to uniquely identify each controller based on the hardware instance when there are multiple ones present in an SoC (even multiple RC/EP). So let's make use of the existing pci_bus_find_domain_nr() API to allocate domain numbers based on either devicetree (linux,pci-domain) property or dynamic domain number allocation scheme. It should be noted that the domain number allocated by this API will be based on both RC and EP controllers in a SoC. If the 'linux,pci-domain' DT property is present, then the domain number represents the actual hardware instance of the PCI endpoint controller. If not, then the domain number will be allocated based on the PCI EP/RC controller probe order. If the architecture doesn't support CONFIG_PCI_DOMAINS_GENERIC (rare), then currently a warning is thrown to indicate that the architecture specific implementation is needed. Link: https://lore.kernel.org/linux-pci/20240828-pci-qcom-hotplug-v4-5-263a385fbbcb@linaro.org Signed-off-by: Manivannan Sadhasivam Signed-off-by: Krzysztof Wilczyński Reviewed-by: Frank Li --- include/linux/pci-epc.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux') diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index 85bdf2adb760..8e3dcac55dcd 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -128,6 +128,7 @@ struct pci_epc_mem { * @group: configfs group representing the PCI EPC device * @lock: mutex to protect pci_epc ops * @function_num_map: bitmap to manage physical function number + * @domain_nr: PCI domain number of the endpoint controller * @init_complete: flag to indicate whether the EPC initialization is complete * or not */ @@ -145,6 +146,7 @@ struct pci_epc { /* mutex to protect against concurrent access of EP controller */ struct mutex lock; unsigned long function_num_map; + int domain_nr; bool init_complete; }; -- cgit v1.2.3 From 0cca961a026177af69044f10d6ae76d8ce043764 Mon Sep 17 00:00:00 2001 From: Manivannan Sadhasivam Date: Thu, 12 Sep 2024 11:00:25 +0530 Subject: PCI: Pass domain number to pci_bus_release_domain_nr() explicitly MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The pci_bus_release_domain_nr() API is supposed to free the domain number allocated by pci_bus_find_domain_nr(). Most of the callers of pci_bus_find_domain_nr(), store the domain number in pci_bus::domain_nr. As such, the pci_bus_release_domain_nr() implicitly frees the domain number by dereferencing 'struct pci_bus'. However, one of the callers of this API, the PCI endpoint subsystem, doesn't have 'struct pci_bus', so it only passes NULL. Due to this, the API will end up dereferencing the NULL pointer. To fix this issue, pass the domain number to this API explicitly. Since 'struct pci_bus' is not used for anything else other than extracting the domain number, it makes sense to pass the domain number directly. Fixes: 0328947c5032 ("PCI: endpoint: Assign PCI domain number for endpoint controllers") Closes: https://lore.kernel.org/linux-pci/c0c40ddb-bf64-4b22-9dd1-8dbb18aa2813@stanley.mountain Link: https://lore.kernel.org/linux-pci/20240912053025.25314-1-manivannan.sadhasivam@linaro.org Reported-by: Dan Carpenter Signed-off-by: Manivannan Sadhasivam [kwilczynski: commit log] Signed-off-by: Krzysztof Wilczyński --- include/linux/pci.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/pci.h b/include/linux/pci.h index 4cf89a4b4cbc..37d97bef060f 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1884,7 +1884,7 @@ static inline int acpi_pci_bus_find_domain_nr(struct pci_bus *bus) { return 0; } #endif int pci_bus_find_domain_nr(struct pci_bus *bus, struct device *parent); -void pci_bus_release_domain_nr(struct pci_bus *bus, struct device *parent); +void pci_bus_release_domain_nr(struct device *parent, int domain_nr); #endif /* Some architectures require additional setup to direct VGA traffic */ -- cgit v1.2.3