From c38ba8e13a554d0bcc7a99d8ada5216ebc449b81 Mon Sep 17 00:00:00 2001 From: Ian Moffett Date: Tue, 4 Jun 2024 14:56:48 -0400 Subject: kernel: Add mmio(9) Signed-off-by: Ian Moffett --- sys/include/sys/mmio.h | 118 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 118 insertions(+) create mode 100644 sys/include/sys/mmio.h (limited to 'sys/include') diff --git a/sys/include/sys/mmio.h b/sys/include/sys/mmio.h new file mode 100644 index 0000000..8f573c3 --- /dev/null +++ b/sys/include/sys/mmio.h @@ -0,0 +1,118 @@ +/* + * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Hyra nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +/* + * For documentation: See mmio(9) + */ + +#ifndef _SYS_MMIO_H_ +#define _SYS_MMIO_H_ + +#include +#include +#if defined(_KERNEL) +#include +#endif + +#if defined(_KERNEL) + + +/* + * mmio_write - Writes to MMIO address with specific size + * + * @addr: Address to write to. + * @val: Value to write. + * + * These functions will add the higher half + * offset (VM_HIGHER_HALF) if the MMIO address + * is less than VM_HIGHER_HALF as it'll be safe + * to assume it's a physical address. Page faults + * from writes could be due to the resulting virtual + * address not being mapped. + */ +#define _MMIO_WRITE_TYPE(TYPE, SUFFIX) \ + static inline void \ + mmio_write##SUFFIX(volatile void *addr, TYPE val) \ + { \ + uintptr_t tmp; \ + \ + tmp = (uintptr_t)addr; \ + if (tmp < VM_HIGHER_HALF) { \ + tmp += VM_HIGHER_HALF; \ + } \ + *(volatile TYPE *)tmp = val; \ + __ASMV("" ::: "memory"); \ + } + +/* + * mmio_read - Does the same as mmio_write but for reading + * + * @addr: Address to read from. + */ +#define _MMIO_READ_TYPE(TYPE, SUFFIX) \ + static inline TYPE \ + mmio_read##SUFFIX(volatile void *addr) \ + { \ + uintptr_t tmp; \ + \ + tmp = (uintptr_t)addr; \ + if (tmp < VM_HIGHER_HALF) { \ + tmp += VM_HIGHER_HALF; \ + } \ + \ + __ASMV("" ::: "memory"); \ + return *(volatile TYPE *)tmp; \ + } + +/* + * To write to an MMIO address of, for example, + * 8 bits, use mmio_write8(addr, val) + */ +_MMIO_WRITE_TYPE(uint8_t, 8) +_MMIO_WRITE_TYPE(uint16_t, 16) +_MMIO_WRITE_TYPE(uint32_t, 32) +#if __SIZEOF_SIZE_T__ == 8 +_MMIO_WRITE_TYPE(uint64_t, 64) +#endif +__extension__ + +/* + * To read from an MMIO address of, for example, + * 8 bits, use mmio_read8(addr) + */ +_MMIO_READ_TYPE(uint8_t, 8) +_MMIO_READ_TYPE(uint16_t, 16) +_MMIO_READ_TYPE(uint32_t, 32) +#if __SIZEOF_SIZE_T__ == 8 +_MMIO_READ_TYPE(uint64_t, 64) +#endif +__extension__ + +#endif /* _KERNEL */ +#endif /* !_SYS_MMIO_H_ */ -- cgit v1.2.3