From b718989da7cf1f77ed5665dba0d2c73bd9dfe2d7 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Thu, 20 Dec 2007 15:28:08 +1100 Subject: [PATCH] PCI: Add pci_enable_device_{io,mem} intefaces The pci_enable_device_bars() interface isn't well suited to PCI because you can't actually enable/disable BARs individually on a device. So for example, if a device has 2 memory BARs 0 and 1, and one of them (let's say 1) has not been successfully allocated by the firmware or the kernel, then enabling memory decoding shouldn't be permitted for the entire device since it will decode whatever random address is still in that BAR 1. So a device must be either fully enabled for IO, for Memory, or for both. Not on a per-BAR basis. This provides two new functions, pci_enable_device_io() and pci_enable_device_mem() to replace pci_enable_device_bars(). The implementation internally builds a BAR mask in order to be able to use existing arch infrastructure. Signed-off-by: Benjamin Herrenschmidt Acked-by: Ivan Kokshaysky Signed-off-by: Greg Kroah-Hartman --- drivers/pci/pci.c | 49 ++++++++++++++++++++++++++++++++++++++++++++- include/linux/pci.h | 2 ++ 2 files changed, 50 insertions(+), 1 deletion(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 7248e9fb12b..5027e4d08b4 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -764,6 +764,51 @@ pci_enable_device_bars(struct pci_dev *dev, int bars) return err; } +static int __pci_enable_device_flags(struct pci_dev *dev, + resource_size_t flags) +{ + int err; + int i, bars = 0; + + if (atomic_add_return(1, &dev->enable_cnt) > 1) + return 0; /* already enabled */ + + for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) + if (dev->resource[i].flags & flags) + bars |= (1 << i); + + err = do_pci_enable_device(dev, bars); + if (err < 0) + atomic_dec(&dev->enable_cnt); + return err; +} + +/** + * pci_enable_device_io - Initialize a device for use with IO space + * @dev: PCI device to be initialized + * + * Initialize device before it's used by a driver. Ask low-level code + * to enable I/O resources. Wake up the device if it was suspended. + * Beware, this function can fail. + */ +int pci_enable_device_io(struct pci_dev *dev) +{ + return __pci_enable_device_flags(dev, IORESOURCE_IO); +} + +/** + * pci_enable_device_mem - Initialize a device for use with Memory space + * @dev: PCI device to be initialized + * + * Initialize device before it's used by a driver. Ask low-level code + * to enable Memory resources. Wake up the device if it was suspended. + * Beware, this function can fail. + */ +int pci_enable_device_mem(struct pci_dev *dev) +{ + return __pci_enable_device_flags(dev, IORESOURCE_MEM); +} + /** * pci_enable_device - Initialize device before it's used by a driver. * @dev: PCI device to be initialized @@ -777,7 +822,7 @@ pci_enable_device_bars(struct pci_dev *dev, int bars) */ int pci_enable_device(struct pci_dev *dev) { - return pci_enable_device_bars(dev, (1 << PCI_NUM_RESOURCES) - 1); + return __pci_enable_device_flags(dev, IORESOURCE_MEM | IORESOURCE_IO); } /* @@ -1651,6 +1696,8 @@ device_initcall(pci_init); EXPORT_SYMBOL(pci_reenable_device); EXPORT_SYMBOL(pci_enable_device_bars); +EXPORT_SYMBOL(pci_enable_device_io); +EXPORT_SYMBOL(pci_enable_device_mem); EXPORT_SYMBOL(pci_enable_device); EXPORT_SYMBOL(pcim_enable_device); EXPORT_SYMBOL(pcim_pin_device); diff --git a/include/linux/pci.h b/include/linux/pci.h index 4b4d711a5da..e4c1dacb663 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -544,6 +544,8 @@ static inline int pci_write_config_dword(struct pci_dev *dev, int where, u32 val int __must_check pci_enable_device(struct pci_dev *dev); int __must_check pci_enable_device_bars(struct pci_dev *dev, int mask); +int __must_check pci_enable_device_io(struct pci_dev *dev); +int __must_check pci_enable_device_mem(struct pci_dev *dev); int __must_check pci_reenable_device(struct pci_dev *); int __must_check pcim_enable_device(struct pci_dev *pdev); void pcim_pin_device(struct pci_dev *pdev); -- 2.41.1