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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/pci/endpoint/pci-epc-mem.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/pci/endpoint/pci-epc-mem.c')
-rw-r--r-- | drivers/pci/endpoint/pci-epc-mem.c | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/drivers/pci/endpoint/pci-epc-mem.c b/drivers/pci/endpoint/pci-epc-mem.c new file mode 100644 index 000000000..a97b56a6d --- /dev/null +++ b/drivers/pci/endpoint/pci-epc-mem.c @@ -0,0 +1,263 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PCI Endpoint *Controller* Address Space Management + * + * Copyright (C) 2017 Texas Instruments + * Author: Kishon Vijay Abraham I <kishon@ti.com> + */ + +#include <linux/io.h> +#include <linux/module.h> +#include <linux/slab.h> + +#include <linux/pci-epc.h> + +/** + * pci_epc_mem_get_order() - determine the allocation order of a memory size + * @mem: address space of the endpoint controller + * @size: the size for which to get the order + * + * Reimplement get_order() for mem->page_size since the generic get_order + * always gets order with a constant PAGE_SIZE. + */ +static int pci_epc_mem_get_order(struct pci_epc_mem *mem, size_t size) +{ + int order; + unsigned int page_shift = ilog2(mem->window.page_size); + + size--; + size >>= page_shift; +#if BITS_PER_LONG == 32 + order = fls(size); +#else + order = fls64(size); +#endif + return order; +} + +/** + * pci_epc_multi_mem_init() - initialize the pci_epc_mem structure + * @epc: the EPC device that invoked pci_epc_mem_init + * @windows: pointer to windows supported by the device + * @num_windows: number of windows device supports + * + * Invoke to initialize the pci_epc_mem structure used by the + * endpoint functions to allocate mapped PCI address. + */ +int pci_epc_multi_mem_init(struct pci_epc *epc, + struct pci_epc_mem_window *windows, + unsigned int num_windows) +{ + struct pci_epc_mem *mem = NULL; + unsigned long *bitmap = NULL; + unsigned int page_shift; + size_t page_size; + int bitmap_size; + int pages; + int ret; + int i; + + epc->num_windows = 0; + + if (!windows || !num_windows) + return -EINVAL; + + epc->windows = kcalloc(num_windows, sizeof(*epc->windows), GFP_KERNEL); + if (!epc->windows) + return -ENOMEM; + + for (i = 0; i < num_windows; i++) { + page_size = windows[i].page_size; + if (page_size < PAGE_SIZE) + page_size = PAGE_SIZE; + page_shift = ilog2(page_size); + pages = windows[i].size >> page_shift; + bitmap_size = BITS_TO_LONGS(pages) * sizeof(long); + + mem = kzalloc(sizeof(*mem), GFP_KERNEL); + if (!mem) { + ret = -ENOMEM; + i--; + goto err_mem; + } + + bitmap = kzalloc(bitmap_size, GFP_KERNEL); + if (!bitmap) { + ret = -ENOMEM; + kfree(mem); + i--; + goto err_mem; + } + + mem->window.phys_base = windows[i].phys_base; + mem->window.size = windows[i].size; + mem->window.page_size = page_size; + mem->bitmap = bitmap; + mem->pages = pages; + mutex_init(&mem->lock); + epc->windows[i] = mem; + } + + epc->mem = epc->windows[0]; + epc->num_windows = num_windows; + + return 0; + +err_mem: + for (; i >= 0; i--) { + mem = epc->windows[i]; + kfree(mem->bitmap); + kfree(mem); + } + kfree(epc->windows); + + return ret; +} +EXPORT_SYMBOL_GPL(pci_epc_multi_mem_init); + +int pci_epc_mem_init(struct pci_epc *epc, phys_addr_t base, + size_t size, size_t page_size) +{ + struct pci_epc_mem_window mem_window; + + mem_window.phys_base = base; + mem_window.size = size; + mem_window.page_size = page_size; + + return pci_epc_multi_mem_init(epc, &mem_window, 1); +} +EXPORT_SYMBOL_GPL(pci_epc_mem_init); + +/** + * pci_epc_mem_exit() - cleanup the pci_epc_mem structure + * @epc: the EPC device that invoked pci_epc_mem_exit + * + * Invoke to cleanup the pci_epc_mem structure allocated in + * pci_epc_mem_init(). + */ +void pci_epc_mem_exit(struct pci_epc *epc) +{ + struct pci_epc_mem *mem; + int i; + + if (!epc->num_windows) + return; + + for (i = 0; i < epc->num_windows; i++) { + mem = epc->windows[i]; + kfree(mem->bitmap); + kfree(mem); + } + kfree(epc->windows); + + epc->windows = NULL; + epc->mem = NULL; + epc->num_windows = 0; +} +EXPORT_SYMBOL_GPL(pci_epc_mem_exit); + +/** + * pci_epc_mem_alloc_addr() - allocate memory address from EPC addr space + * @epc: the EPC device on which memory has to be allocated + * @phys_addr: populate the allocated physical address here + * @size: the size of the address space that has to be allocated + * + * Invoke to allocate memory address from the EPC address space. This + * is usually done to map the remote RC address into the local system. + */ +void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, + phys_addr_t *phys_addr, size_t size) +{ + void __iomem *virt_addr = NULL; + struct pci_epc_mem *mem; + unsigned int page_shift; + size_t align_size; + int pageno; + int order; + int i; + + for (i = 0; i < epc->num_windows; i++) { + mem = epc->windows[i]; + mutex_lock(&mem->lock); + align_size = ALIGN(size, mem->window.page_size); + order = pci_epc_mem_get_order(mem, align_size); + + pageno = bitmap_find_free_region(mem->bitmap, mem->pages, + order); + if (pageno >= 0) { + page_shift = ilog2(mem->window.page_size); + *phys_addr = mem->window.phys_base + + ((phys_addr_t)pageno << page_shift); + virt_addr = ioremap(*phys_addr, align_size); + if (!virt_addr) { + bitmap_release_region(mem->bitmap, + pageno, order); + mutex_unlock(&mem->lock); + continue; + } + mutex_unlock(&mem->lock); + return virt_addr; + } + mutex_unlock(&mem->lock); + } + + return virt_addr; +} +EXPORT_SYMBOL_GPL(pci_epc_mem_alloc_addr); + +static struct pci_epc_mem *pci_epc_get_matching_window(struct pci_epc *epc, + phys_addr_t phys_addr) +{ + struct pci_epc_mem *mem; + int i; + + for (i = 0; i < epc->num_windows; i++) { + mem = epc->windows[i]; + + if (phys_addr >= mem->window.phys_base && + phys_addr < (mem->window.phys_base + mem->window.size)) + return mem; + } + + return NULL; +} + +/** + * pci_epc_mem_free_addr() - free the allocated memory address + * @epc: the EPC device on which memory was allocated + * @phys_addr: the allocated physical address + * @virt_addr: virtual address of the allocated mem space + * @size: the size of the allocated address space + * + * Invoke to free the memory allocated using pci_epc_mem_alloc_addr. + */ +void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr, + void __iomem *virt_addr, size_t size) +{ + struct pci_epc_mem *mem; + unsigned int page_shift; + size_t page_size; + int pageno; + int order; + + mem = pci_epc_get_matching_window(epc, phys_addr); + if (!mem) { + pr_err("failed to get matching window\n"); + return; + } + + page_size = mem->window.page_size; + page_shift = ilog2(page_size); + iounmap(virt_addr); + pageno = (phys_addr - mem->window.phys_base) >> page_shift; + size = ALIGN(size, page_size); + order = pci_epc_mem_get_order(mem, size); + mutex_lock(&mem->lock); + bitmap_release_region(mem->bitmap, pageno, order); + mutex_unlock(&mem->lock); +} +EXPORT_SYMBOL_GPL(pci_epc_mem_free_addr); + +MODULE_DESCRIPTION("PCI EPC Address Space Management"); +MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>"); +MODULE_LICENSE("GPL v2"); |