From 4e2f95b789d8f3b505f52c42b634401dd5f718a2 Mon Sep 17 00:00:00 2001 From: Patrick Rudolph Date: Wed, 16 May 2018 14:56:22 +0200 Subject: device/pci: Add MSI-X helper functions Basic PCI MSI-X table helper functions. Imported from GNU/Linux kernel PCI subsystem. To be used on Cavium to configure MSI-X tables. Change-Id: I94413712e7986efd17e6b11ba59f6eb390384c8c Signed-off-by: Patrick Rudolph Reviewed-on: https://review.coreboot.org/26329 Reviewed-by: Philipp Deppenwiese Tested-by: build bot (Jenkins) --- src/device/pci_device.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) (limited to 'src/device') diff --git a/src/device/pci_device.c b/src/device/pci_device.c index c18f529fbe..593838909c 100644 --- a/src/device/pci_device.c +++ b/src/device/pci_device.c @@ -337,6 +337,74 @@ static void pci_get_rom_resource(struct device *dev, unsigned long index) compact_resources(dev); } +/** + * Given a device, read the size of the MSI-X table. + * + * @param dev Pointer to the device structure. + * @return MSI-X table size or 0 if not MSI-X capable device + */ +size_t pci_msix_table_size(struct device *dev) +{ + const size_t pos = pci_find_capability(dev, PCI_CAP_ID_MSIX); + if (!pos) + return 0; + + const u16 control = pci_read_config16(dev, pos + PCI_MSIX_FLAGS); + return (control & PCI_MSIX_FLAGS_QSIZE) + 1; +} + +/** + * Given a device, return the table offset and bar the MSI-X tables resides in. + * + * @param dev Pointer to the device structure. + * @param offset Returned value gives the offset in bytes inside the PCI BAR. + * @param idx The returned value is the index of the PCI_BASE_ADDRESS register + * the MSI-X table is located in. + * @return Zero on success + */ +int pci_msix_table_bar(struct device *dev, u32 *offset, u8 *idx) +{ + const size_t pos = pci_find_capability(dev, PCI_CAP_ID_MSIX); + if (!pos || !offset || !idx) + return 1; + + *offset = pci_read_config32(dev, pos + PCI_MSIX_TABLE); + *idx = (u8)(*offset & PCI_MSIX_PBA_BIR); + *offset &= PCI_MSIX_PBA_OFFSET; + + return 0; +} + +/** + * Given a device, return a msix_entry pointer or NULL if no table was found. + * + * @param dev Pointer to the device structure. + * + * @return NULL on error + */ +struct msix_entry *pci_msix_get_table(struct device *dev) +{ + struct resource *res; + u32 offset; + u8 idx; + + if (pci_msix_table_bar(dev, &offset, &idx)) + return NULL; + + if (idx > 5) + return NULL; + + res = probe_resource(dev, idx * 4 + PCI_BASE_ADDRESS_0); + if (!res || !res->base || offset >= res->size) + return NULL; + + if ((res->flags & IORESOURCE_PCI64) && + (uintptr_t)res->base != res->base) + return NULL; + + return (struct msix_entry *)((uintptr_t)res->base + offset); +} + /** * Read the base address registers for a given device. * -- cgit v1.2.3