From 1e9efe6c9976552e88c6e6feaca3a78b8cf5aaf6 Mon Sep 17 00:00:00 2001 From: Kishon Vijay Abraham I Date: Mon, 14 Jan 2019 16:45:05 +0530 Subject: [PATCH] PCI: endpoint: Add helper to get first unreserved BAR Add a helper function pci_epc_get_first_free_bar() to get the first unreserved BAR that can be used for endpoint function. Tested-by: Gustavo Pimentel Signed-off-by: Kishon Vijay Abraham I Signed-off-by: Lorenzo Pieralisi --- drivers/pci/endpoint/pci-epc-core.c | 23 +++++++++++++++++++++++ include/linux/pci-epc.h | 2 ++ 2 files changed, 25 insertions(+) diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c index 5a099479d9ab..e4712a0f249c 100644 --- a/drivers/pci/endpoint/pci-epc-core.c +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -83,6 +83,29 @@ err: } EXPORT_SYMBOL_GPL(pci_epc_get); +/** + * pci_epc_get_first_free_bar() - helper to get first unreserved BAR + * @epc_features: pci_epc_features structure that holds the reserved bar bitmap + * + * Invoke to get the first unreserved BAR that can be used for endpoint + * function. For any incorrect value in reserved_bar return '0'. + */ +unsigned int pci_epc_get_first_free_bar(const struct pci_epc_features + *epc_features) +{ + int free_bar; + + if (!epc_features) + return 0; + + free_bar = ffz(epc_features->reserved_bar); + if (free_bar > 5) + return 0; + + return free_bar; +} +EXPORT_SYMBOL_GPL(pci_epc_get_first_free_bar); + /** * pci_epc_get_features() - get the features supported by EPC * @epc: the features supported by *this* EPC device will be returned diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index 79fbcf94e14d..94e1ecff98ce 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -180,6 +180,8 @@ int pci_epc_start(struct pci_epc *epc); void pci_epc_stop(struct pci_epc *epc); const struct pci_epc_features *pci_epc_get_features(struct pci_epc *epc, u8 func_no); +unsigned int pci_epc_get_first_free_bar(const struct pci_epc_features + *epc_features); struct pci_epc *pci_epc_get(const char *epc_name); void pci_epc_put(struct pci_epc *epc);