1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited 4 */ 5 #ifndef _ASM_IO_H 6 #define _ASM_IO_H 7 8 #define ARCH_HAS_IOREMAP_WC 9 10 #include <linux/compiler.h> 11 #include <linux/kernel.h> 12 #include <linux/types.h> 13 14 #include <asm/addrspace.h> 15 #include <asm/bug.h> 16 #include <asm/byteorder.h> 17 #include <asm/cpu.h> 18 #include <asm/page.h> 19 #include <asm/pgtable-bits.h> 20 #include <asm/string.h> 21 22 /* 23 * On LoongArch, I/O ports mappring is following: 24 * 25 * | .... | 26 * |-----------------------| 27 * | pci io ports(64K~32M) | 28 * |-----------------------| 29 * | isa io ports(0 ~16K) | 30 * PCI_IOBASE ->|-----------------------| 31 * | .... | 32 */ 33 #define PCI_IOBASE ((void __iomem *)(vm_map_base + (2 * PAGE_SIZE))) 34 #define PCI_IOSIZE SZ_32M 35 #define ISA_IOSIZE SZ_16K 36 #define IO_SPACE_LIMIT (PCI_IOSIZE - 1) 37 38 /* 39 * Change "struct page" to physical address. 40 */ 41 #define page_to_phys(page) ((phys_addr_t)page_to_pfn(page) << PAGE_SHIFT) 42 43 extern void __init __iomem *early_ioremap(u64 phys_addr, unsigned long size); 44 extern void __init early_iounmap(void __iomem *addr, unsigned long size); 45 46 #define early_memremap early_ioremap 47 #define early_memunmap early_iounmap 48 49 static inline void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size, 50 unsigned long prot_val) 51 { 52 if (prot_val == _CACHE_CC) 53 return (void __iomem *)(unsigned long)(CACHE_BASE + offset); 54 else 55 return (void __iomem *)(unsigned long)(UNCACHE_BASE + offset); 56 } 57 58 /* 59 * ioremap - map bus memory into CPU space 60 * @offset: bus address of the memory 61 * @size: size of the resource to map 62 * 63 * ioremap performs a platform specific sequence of operations to 64 * make bus memory CPU accessible via the readb/readw/readl/writeb/ 65 * writew/writel functions and the other mmio helpers. The returned 66 * address is not guaranteed to be usable directly as a virtual 67 * address. 68 */ 69 #define ioremap(offset, size) \ 70 ioremap_prot((offset), (size), _CACHE_SUC) 71 72 /* 73 * ioremap_wc - map bus memory into CPU space 74 * @offset: bus address of the memory 75 * @size: size of the resource to map 76 * 77 * ioremap_wc performs a platform specific sequence of operations to 78 * make bus memory CPU accessible via the readb/readw/readl/writeb/ 79 * writew/writel functions and the other mmio helpers. The returned 80 * address is not guaranteed to be usable directly as a virtual 81 * address. 82 * 83 * This version of ioremap ensures that the memory is marked uncachable 84 * but accelerated by means of write-combining feature. It is specifically 85 * useful for PCIe prefetchable windows, which may vastly improve a 86 * communications performance. If it was determined on boot stage, what 87 * CPU CCA doesn't support WUC, the method shall fall-back to the 88 * _CACHE_SUC option (see cpu_probe() method). 89 */ 90 #define ioremap_wc(offset, size) \ 91 ioremap_prot((offset), (size), _CACHE_WUC) 92 93 /* 94 * ioremap_cache - map bus memory into CPU space 95 * @offset: bus address of the memory 96 * @size: size of the resource to map 97 * 98 * ioremap_cache performs a platform specific sequence of operations to 99 * make bus memory CPU accessible via the readb/readw/readl/writeb/ 100 * writew/writel functions and the other mmio helpers. The returned 101 * address is not guaranteed to be usable directly as a virtual 102 * address. 103 * 104 * This version of ioremap ensures that the memory is marked cachable by 105 * the CPU. Also enables full write-combining. Useful for some 106 * memory-like regions on I/O busses. 107 */ 108 #define ioremap_cache(offset, size) \ 109 ioremap_prot((offset), (size), _CACHE_CC) 110 111 static inline void iounmap(const volatile void __iomem *addr) 112 { 113 } 114 115 #define mmiowb() asm volatile ("dbar 0" ::: "memory") 116 117 /* 118 * String version of I/O memory access operations. 119 */ 120 extern void __memset_io(volatile void __iomem *dst, int c, size_t count); 121 extern void __memcpy_toio(volatile void __iomem *to, const void *from, size_t count); 122 extern void __memcpy_fromio(void *to, const volatile void __iomem *from, size_t count); 123 #define memset_io(c, v, l) __memset_io((c), (v), (l)) 124 #define memcpy_fromio(a, c, l) __memcpy_fromio((a), (c), (l)) 125 #define memcpy_toio(c, a, l) __memcpy_toio((c), (a), (l)) 126 127 #include <asm-generic/io.h> 128 129 #endif /* _ASM_IO_H */ 130