From 52c9285d47459cf241e144c7d8ef15941ba1b181 Mon Sep 17 00:00:00 2001 From: Kishon Vijay Abraham I Date: Fri, 18 Aug 2017 20:27:56 +0530 Subject: [PATCH] PCI: endpoint: Add support for configurable page size MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit pci-epc-mem uses a page size equal to *PAGE_SIZE* (usually 4KB) to manage the address space. However certain platforms like TI's K2G have a restriction that this address space should be either divided into 1MB/2MB/4MB or 8MB sizes (Ref: 11.14.4.9.1 Outbound Address Translation in K2G TRM SPRUHY8F January 2016 – Revised May 2017). Add support to handle different page sizes here. Signed-off-by: Kishon Vijay Abraham I Signed-off-by: Bjorn Helgaas --- drivers/pci/endpoint/pci-epc-mem.c | 59 ++++++++++++++++++++++++++++++++------ include/linux/pci-epc.h | 8 +++++- 2 files changed, 57 insertions(+), 10 deletions(-) diff --git a/drivers/pci/endpoint/pci-epc-mem.c b/drivers/pci/endpoint/pci-epc-mem.c index 3a94cc1..83b7d5d 100644 --- a/drivers/pci/endpoint/pci-epc-mem.c +++ b/drivers/pci/endpoint/pci-epc-mem.c @@ -24,21 +24,54 @@ #include /** - * pci_epc_mem_init() - initialize the pci_epc_mem structure + * 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->page_size); + + size--; + size >>= page_shift; +#if BITS_PER_LONG == 32 + order = fls(size); +#else + order = fls64(size); +#endif + return order; +} + +/** + * __pci_epc_mem_init() - initialize the pci_epc_mem structure * @epc: the EPC device that invoked pci_epc_mem_init * @phys_base: the physical address of the base * @size: the size of the address space + * @page_size: size of each page * * Invoke to initialize the pci_epc_mem structure used by the * endpoint functions to allocate mapped PCI address. */ -int pci_epc_mem_init(struct pci_epc *epc, phys_addr_t phys_base, size_t size) +int __pci_epc_mem_init(struct pci_epc *epc, phys_addr_t phys_base, size_t size, + size_t page_size) { int ret; struct pci_epc_mem *mem; unsigned long *bitmap; - int pages = size >> PAGE_SHIFT; - int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long); + unsigned int page_shift; + int pages; + int bitmap_size; + + if (page_size < PAGE_SIZE) + page_size = PAGE_SIZE; + + page_shift = ilog2(page_size); + pages = size >> page_shift; + bitmap_size = BITS_TO_LONGS(pages) * sizeof(long); mem = kzalloc(sizeof(*mem), GFP_KERNEL); if (!mem) { @@ -54,6 +87,7 @@ int pci_epc_mem_init(struct pci_epc *epc, phys_addr_t phys_base, size_t size) mem->bitmap = bitmap; mem->phys_base = phys_base; + mem->page_size = page_size; mem->pages = pages; mem->size = size; @@ -67,7 +101,7 @@ err_mem: err: return ret; } -EXPORT_SYMBOL_GPL(pci_epc_mem_init); +EXPORT_SYMBOL_GPL(__pci_epc_mem_init); /** * pci_epc_mem_exit() - cleanup the pci_epc_mem structure @@ -101,13 +135,17 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, int pageno; void __iomem *virt_addr; struct pci_epc_mem *mem = epc->mem; - int order = get_order(size); + unsigned int page_shift = ilog2(mem->page_size); + int order; + + size = ALIGN(size, mem->page_size); + order = pci_epc_mem_get_order(mem, size); pageno = bitmap_find_free_region(mem->bitmap, mem->pages, order); if (pageno < 0) return NULL; - *phys_addr = mem->phys_base + (pageno << PAGE_SHIFT); + *phys_addr = mem->phys_base + (pageno << page_shift); virt_addr = ioremap(*phys_addr, size); if (!virt_addr) bitmap_release_region(mem->bitmap, pageno, order); @@ -129,11 +167,14 @@ void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr, void __iomem *virt_addr, size_t size) { int pageno; - int order = get_order(size); struct pci_epc_mem *mem = epc->mem; + unsigned int page_shift = ilog2(mem->page_size); + int order; iounmap(virt_addr); - pageno = (phys_addr - mem->phys_base) >> PAGE_SHIFT; + pageno = (phys_addr - mem->phys_base) >> page_shift; + size = ALIGN(size, mem->page_size); + order = pci_epc_mem_get_order(mem, size); bitmap_release_region(mem->bitmap, pageno, order); } EXPORT_SYMBOL_GPL(pci_epc_mem_free_addr); diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index af5edbf..f7a04e1 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -62,11 +62,13 @@ struct pci_epc_ops { * @size: the size of the PCI address space * @bitmap: bitmap to manage the PCI address space * @pages: number of bits representing the address region + * @page_size: size of each page */ struct pci_epc_mem { phys_addr_t phys_base; size_t size; unsigned long *bitmap; + size_t page_size; int pages; }; @@ -98,6 +100,9 @@ struct pci_epc { #define devm_pci_epc_create(dev, ops) \ __devm_pci_epc_create((dev), (ops), THIS_MODULE) +#define pci_epc_mem_init(epc, phys_addr, size) \ + __pci_epc_mem_init((epc), (phys_addr), (size), PAGE_SIZE) + static inline void epc_set_drvdata(struct pci_epc *epc, void *data) { dev_set_drvdata(&epc->dev, data); @@ -135,7 +140,8 @@ void pci_epc_stop(struct pci_epc *epc); struct pci_epc *pci_epc_get(const char *epc_name); void pci_epc_put(struct pci_epc *epc); -int pci_epc_mem_init(struct pci_epc *epc, phys_addr_t phys_addr, size_t size); +int __pci_epc_mem_init(struct pci_epc *epc, phys_addr_t phys_addr, size_t size, + size_t page_size); void pci_epc_mem_exit(struct pci_epc *epc); void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, phys_addr_t *phys_addr, size_t size); -- 2.7.4