From: Phani R Burra <[email protected]> Add memory related support functions for drivers to access MMIO space and allocate/free dma buffers.
Reviewed-by: Maciej Fijalkowski <[email protected]> Signed-off-by: Phani R Burra <[email protected]> Co-developed-by: Victor Raj <[email protected]> Signed-off-by: Victor Raj <[email protected]> Co-developed-by: Sridhar Samudrala <[email protected]> Signed-off-by: Sridhar Samudrala <[email protected]> Co-developed-by: Pavan Kumar Linga <[email protected]> Signed-off-by: Pavan Kumar Linga <[email protected]> Co-developed-by: Larysa Zaremba <[email protected]> Signed-off-by: Larysa Zaremba <[email protected]> --- drivers/net/ethernet/intel/libeth/Kconfig | 6 + drivers/net/ethernet/intel/libeth/Makefile | 4 + drivers/net/ethernet/intel/libeth/pci.c | 184 +++++++++++++++++++++ include/net/libeth/pci.h | 55 ++++++ 4 files changed, 249 insertions(+) create mode 100644 drivers/net/ethernet/intel/libeth/pci.c create mode 100644 include/net/libeth/pci.h diff --git a/drivers/net/ethernet/intel/libeth/Kconfig b/drivers/net/ethernet/intel/libeth/Kconfig index 480293b71dbc..070ad685fb74 100644 --- a/drivers/net/ethernet/intel/libeth/Kconfig +++ b/drivers/net/ethernet/intel/libeth/Kconfig @@ -7,3 +7,9 @@ config LIBETH help libeth is a common library containing routines shared between several drivers, but not yet promoted to the generic kernel API. + +config LIBETH_PCI + tristate + help + Helper functions for management of PCI resources belonging + to networking devices. diff --git a/drivers/net/ethernet/intel/libeth/Makefile b/drivers/net/ethernet/intel/libeth/Makefile index 52492b081132..5f0fc9446acb 100644 --- a/drivers/net/ethernet/intel/libeth/Makefile +++ b/drivers/net/ethernet/intel/libeth/Makefile @@ -4,3 +4,7 @@ obj-$(CONFIG_LIBETH) += libeth.o libeth-y := rx.o + +obj-$(CONFIG_LIBETH_PCI) += libeth_pci.o + +libeth_pci-y := pci.o diff --git a/drivers/net/ethernet/intel/libeth/pci.c b/drivers/net/ethernet/intel/libeth/pci.c new file mode 100644 index 000000000000..63cf56a07ce9 --- /dev/null +++ b/drivers/net/ethernet/intel/libeth/pci.c @@ -0,0 +1,184 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (C) 2025 Intel Corporation */ + +#include <net/libeth/pci.h> + +/** + * libeth_find_mmio_region - find if MMIO region is present in the list + * @mmio_list: list that contains MMIO region info + * @offset: MMIO region start offset + * @bar_idx: BAR index where the offset to search + * + * Return: MMIO region pointer or NULL if the region info is not present. + */ +static struct libeth_pci_mmio_region * +libeth_find_mmio_region(const struct list_head *mmio_list, + resource_size_t offset, int bar_idx) +{ + struct libeth_pci_mmio_region *mr; + + list_for_each_entry(mr, mmio_list, list) + if (mr->bar_idx == bar_idx && mr->offset == offset) + return mr; + + return NULL; +} + +/** + * __libeth_pci_get_mmio_addr - get the MMIO virtual address + * @mmio_info: contains list of MMIO regions + * @offset: register offset of find + * @num_args: number of additional arguments present + * + * This function finds the virtual address of a register offset by iterating + * through the non-linear MMIO regions that are mapped by the driver. + * + * Return: valid MMIO virtual address or NULL. + */ +void __iomem *__libeth_pci_get_mmio_addr(struct libeth_mmio_info *mmio_info, + resource_size_t offset, + int num_args, ...) +{ + struct libeth_pci_mmio_region *mr; + int bar_idx = 0; + va_list args; + + if (num_args) { + va_start(args, num_args); + bar_idx = va_arg(args, int); + va_end(args); + } + + list_for_each_entry(mr, &mmio_info->mmio_list, list) + if (bar_idx == mr->bar_idx && offset >= mr->offset && + offset < mr->offset + mr->size) { + offset -= mr->offset; + + return mr->addr + offset; + } + + return NULL; +} +EXPORT_SYMBOL_NS_GPL(__libeth_pci_get_mmio_addr, "LIBETH_PCI"); + +/** + * __libeth_pci_map_mmio_region - map PCI device MMIO region + * @mmio_info: struct to store the mapped MMIO region + * @offset: MMIO region start offset + * @size: MMIO region size + * @num_args: number of additional arguments present + * + * Return: true on success, false on memory map failure. + */ +bool __libeth_pci_map_mmio_region(struct libeth_mmio_info *mmio_info, + resource_size_t offset, + resource_size_t size, int num_args, ...) +{ + struct pci_dev *pdev = mmio_info->pdev; + struct libeth_pci_mmio_region *mr; + resource_size_t pa; + void __iomem *va; + int bar_idx = 0; + va_list args; + + if (num_args) { + va_start(args, num_args); + bar_idx = va_arg(args, int); + va_end(args); + } + + mr = libeth_find_mmio_region(&mmio_info->mmio_list, offset, bar_idx); + if (mr) { + pci_warn(pdev, "Mapping of BAR%u with offset %llu already exists\n", + bar_idx, offset); + return true; + } + + pa = pci_resource_start(pdev, bar_idx) + offset; + va = ioremap(pa, size); + if (!va) { + pci_err(pdev, "Failed to allocate BAR%u region\n", bar_idx); + return false; + } + + mr = kvzalloc(sizeof(*mr), GFP_KERNEL); + if (!mr) { + iounmap(va); + return false; + } + + mr->addr = va; + mr->offset = offset; + mr->size = size; + mr->bar_idx = bar_idx; + + list_add_tail(&mr->list, &mmio_info->mmio_list); + + return true; +} +EXPORT_SYMBOL_NS_GPL(__libeth_pci_map_mmio_region, "LIBETH_PCI"); + +/** + * libeth_pci_unmap_all_mmio_regions - unmap all PCI device MMIO regions + * @mmio_info: contains list of MMIO regions to unmap + */ +void libeth_pci_unmap_all_mmio_regions(struct libeth_mmio_info *mmio_info) +{ + struct libeth_pci_mmio_region *mr, *tmp; + + list_for_each_entry_safe(mr, tmp, &mmio_info->mmio_list, list) { + iounmap(mr->addr); + list_del(&mr->list); + kfree(mr); + } +} +EXPORT_SYMBOL_NS_GPL(libeth_pci_unmap_all_mmio_regions, "LIBETH_PCI"); + +/** + * libeth_pci_init_dev - enable and reserve PCI regions of the device + * @pdev: PCI device information + * + * Return: %0 on success, -%errno on failure. + */ +int libeth_pci_init_dev(struct pci_dev *pdev) +{ + int err; + + err = pci_enable_device(pdev); + if (err) + return err; + + err = pci_request_mem_regions(pdev, pci_name(pdev)); + if (err) + goto disable_dev; + + err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); + if (err) + goto rel_regions; + + pci_set_master(pdev); + + return 0; + +rel_regions: + pci_release_regions(pdev); +disable_dev: + pci_disable_device(pdev); + + return err; +} +EXPORT_SYMBOL_NS_GPL(libeth_pci_init_dev, "LIBETH_PCI"); + +/** + * libeth_pci_deinit_dev - disable and release the PCI regions of the device + * @pdev: PCI device information + */ +void libeth_pci_deinit_dev(struct pci_dev *pdev) +{ + pci_disable_device(pdev); + pci_release_regions(pdev); +} +EXPORT_SYMBOL_NS_GPL(libeth_pci_deinit_dev, "LIBETH_PCI"); + +MODULE_DESCRIPTION("Common Ethernet PCI library"); +MODULE_LICENSE("GPL"); diff --git a/include/net/libeth/pci.h b/include/net/libeth/pci.h new file mode 100644 index 000000000000..6ae8032c2c8a --- /dev/null +++ b/include/net/libeth/pci.h @@ -0,0 +1,55 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* Copyright (C) 2025 Intel Corporation */ + +#ifndef __LIBETH_PCI_H +#define __LIBETH_PCI_H + +#include <linux/pci.h> + +/** + * struct libeth_pci_mmio_region - structure for MMIO region info + * @list: used to add a MMIO region to the list of MMIO regions in + * libeth_mmio_info + * @addr: virtual address of MMIO region start + * @offset: start offset of the MMIO region + * @size: size of the MMIO region + * @bar_idx: BAR index to which the MMIO region belongs to + */ +struct libeth_pci_mmio_region { + struct list_head list; + void __iomem *addr; + resource_size_t offset; + resource_size_t size; + u16 bar_idx; +}; + +/** + * struct libeth_mmio_info - contains list of MMIO regions + * @pdev: PCI device pointer + * @mmio_list: list of MMIO regions + */ +struct libeth_mmio_info { + struct pci_dev *pdev; + struct list_head mmio_list; +}; + +#define libeth_pci_map_mmio_region(mmio_info, offset, size, ...) \ + __libeth_pci_map_mmio_region(mmio_info, offset, size, \ + COUNT_ARGS(__VA_ARGS__), ##__VA_ARGS__) + +#define libeth_pci_get_mmio_addr(mmio_info, offset, ...) \ + __libeth_pci_get_mmio_addr(mmio_info, offset, \ + COUNT_ARGS(__VA_ARGS__), ##__VA_ARGS__) + +bool __libeth_pci_map_mmio_region(struct libeth_mmio_info *mmio_info, + resource_size_t offset, + resource_size_t size, + int num_args, ...); +void __iomem *__libeth_pci_get_mmio_addr(struct libeth_mmio_info *mmio_info, + resource_size_t region_offset, + int num_args, ...); +void libeth_pci_unmap_all_mmio_regions(struct libeth_mmio_info *mmio_info); +int libeth_pci_init_dev(struct pci_dev *pdev); +void libeth_pci_deinit_dev(struct pci_dev *pdev); + +#endif /* __LIBETH_PCI_H */ -- 2.47.0
