diff options
| -rw-r--r-- | drivers/pci/rebar.c | 23 | ||||
| -rw-r--r-- | include/linux/pci.h | 1 |
2 files changed, 24 insertions, 0 deletions
diff --git a/drivers/pci/rebar.c b/drivers/pci/rebar.c index 1c90b606b8d4..e99b89bd5e51 100644 --- a/drivers/pci/rebar.c +++ b/drivers/pci/rebar.c @@ -5,6 +5,7 @@ #include <linux/bits.h> #include <linux/bitfield.h> +#include <linux/bitops.h> #include <linux/errno.h> #include <linux/export.h> #include <linux/ioport.h> @@ -143,6 +144,28 @@ bool pci_rebar_size_supported(struct pci_dev *pdev, int bar, int size) EXPORT_SYMBOL_GPL(pci_rebar_size_supported); /** + * pci_rebar_get_max_size - get the maximum supported size of a BAR + * @pdev: PCI device + * @bar: BAR to query + * + * Get the largest supported size of a resizable BAR as a size. + * + * Return: the encoded maximum BAR size as defined in the PCIe spec + * (0=1MB, 31=128TB), or %-NOENT on error. + */ +int pci_rebar_get_max_size(struct pci_dev *pdev, int bar) +{ + u32 sizes; + + sizes = pci_rebar_get_possible_sizes(pdev, bar); + if (!sizes) + return -ENOENT; + + return __fls(sizes); +} +EXPORT_SYMBOL_GPL(pci_rebar_get_max_size); + +/** * pci_rebar_get_current_size - get the current size of a Resizable BAR * @pdev: PCI device * @bar: BAR to get the size from diff --git a/include/linux/pci.h b/include/linux/pci.h index 0ef827cfaf0c..898bc3a4e8e7 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1425,6 +1425,7 @@ int pci_rebar_bytes_to_size(u64 bytes); resource_size_t pci_rebar_size_to_bytes(int size); u32 pci_rebar_get_possible_sizes(struct pci_dev *pdev, int bar); bool pci_rebar_size_supported(struct pci_dev *pdev, int bar, int size); +int pci_rebar_get_max_size(struct pci_dev *pdev, int bar); int __must_check pci_resize_resource(struct pci_dev *dev, int i, int size, int exclude_bars); |