diff options
Diffstat (limited to 'arch/arm64/kernel/io.c')
| -rw-r--r-- | arch/arm64/kernel/io.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/arch/arm64/kernel/io.c b/arch/arm64/kernel/io.c new file mode 100644 index 000000000..fe86ada23 --- /dev/null +++ b/arch/arm64/kernel/io.c @@ -0,0 +1,52 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Based on arch/arm/kernel/io.c + * + * Copyright (C) 2012 ARM Ltd. + */ + +#include <linux/export.h> +#include <linux/types.h> +#include <linux/io.h> + +/* + * This generates a memcpy that works on a from/to address which is aligned to + * bits. Count is in terms of the number of bits sized quantities to copy. It + * optimizes to use the STR groupings when possible so that it is WC friendly. + */ +#define memcpy_toio_aligned(to, from, count, bits) \ + ({ \ + volatile u##bits __iomem *_to = to; \ + const u##bits *_from = from; \ + size_t _count = count; \ + const u##bits *_end_from = _from + ALIGN_DOWN(_count, 8); \ + \ + for (; _from < _end_from; _from += 8, _to += 8) \ + __const_memcpy_toio_aligned##bits(_to, _from, 8); \ + if ((_count % 8) >= 4) { \ + __const_memcpy_toio_aligned##bits(_to, _from, 4); \ + _from += 4; \ + _to += 4; \ + } \ + if ((_count % 4) >= 2) { \ + __const_memcpy_toio_aligned##bits(_to, _from, 2); \ + _from += 2; \ + _to += 2; \ + } \ + if (_count % 2) \ + __const_memcpy_toio_aligned##bits(_to, _from, 1); \ + }) + +void __iowrite64_copy_full(void __iomem *to, const void *from, size_t count) +{ + memcpy_toio_aligned(to, from, count, 64); + dgh(); +} +EXPORT_SYMBOL(__iowrite64_copy_full); + +void __iowrite32_copy_full(void __iomem *to, const void *from, size_t count) +{ + memcpy_toio_aligned(to, from, count, 32); + dgh(); +} +EXPORT_SYMBOL(__iowrite32_copy_full); |
