1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #include <linux/export.h> |
3 | #include <linux/types.h> |
4 | #include <linux/io.h> |
5 | #include <linux/spinlock.h> |
6 | |
7 | static DEFINE_RAW_SPINLOCK(__io_lock); |
8 | |
9 | /* |
10 | * Generic atomic MMIO modify. |
11 | * |
12 | * Allows thread-safe access to registers shared by unrelated subsystems. |
13 | * The access is protected by a single MMIO-wide lock. |
14 | */ |
15 | void atomic_io_modify_relaxed(void __iomem *reg, u32 mask, u32 set) |
16 | { |
17 | unsigned long flags; |
18 | u32 value; |
19 | |
20 | raw_spin_lock_irqsave(&__io_lock, flags); |
21 | value = readl_relaxed(reg) & ~mask; |
22 | value |= (set & mask); |
23 | writel_relaxed(value, reg); |
24 | raw_spin_unlock_irqrestore(&__io_lock, flags); |
25 | } |
26 | EXPORT_SYMBOL(atomic_io_modify_relaxed); |
27 | |
28 | void atomic_io_modify(void __iomem *reg, u32 mask, u32 set) |
29 | { |
30 | unsigned long flags; |
31 | u32 value; |
32 | |
33 | raw_spin_lock_irqsave(&__io_lock, flags); |
34 | value = readl_relaxed(reg) & ~mask; |
35 | value |= (set & mask); |
36 | writel(val: value, addr: reg); |
37 | raw_spin_unlock_irqrestore(&__io_lock, flags); |
38 | } |
39 | EXPORT_SYMBOL(atomic_io_modify); |
40 | |
41 | /* |
42 | * Copy data from IO memory space to "real" memory space. |
43 | * This needs to be optimized. |
44 | */ |
45 | void _memcpy_fromio(void *to, const volatile void __iomem *from, size_t count) |
46 | { |
47 | unsigned char *t = to; |
48 | while (count) { |
49 | count--; |
50 | *t = readb(addr: from); |
51 | t++; |
52 | from++; |
53 | } |
54 | } |
55 | EXPORT_SYMBOL(_memcpy_fromio); |
56 | |
57 | /* |
58 | * Copy data from "real" memory space to IO memory space. |
59 | * This needs to be optimized. |
60 | */ |
61 | void _memcpy_toio(volatile void __iomem *to, const void *from, size_t count) |
62 | { |
63 | const unsigned char *f = from; |
64 | while (count) { |
65 | count--; |
66 | writeb(val: *f, addr: to); |
67 | f++; |
68 | to++; |
69 | } |
70 | } |
71 | EXPORT_SYMBOL(_memcpy_toio); |
72 | |
73 | /* |
74 | * "memset" on IO memory space. |
75 | * This needs to be optimized. |
76 | */ |
77 | void _memset_io(volatile void __iomem *dst, int c, size_t count) |
78 | { |
79 | while (count) { |
80 | count--; |
81 | writeb(val: c, addr: dst); |
82 | dst++; |
83 | } |
84 | } |
85 | EXPORT_SYMBOL(_memset_io); |
86 | |