diff options
Diffstat (limited to 'sys/arch/amd64/tss.c')
| -rw-r--r-- | sys/arch/amd64/tss.c | 158 |
1 files changed, 0 insertions, 158 deletions
diff --git a/sys/arch/amd64/tss.c b/sys/arch/amd64/tss.c deleted file mode 100644 index b1b5420..0000000 --- a/sys/arch/amd64/tss.c +++ /dev/null @@ -1,158 +0,0 @@ -/* - * Copyright (c) 2023 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. - */ - -#include <machine/tss.h> -#include <machine/cpu.h> -#include <lib/string.h> -#include <vm/dynalloc.h> -#include <sys/panic.h> -#include <sys/errno.h> -#include <assert.h> - -__MODULE_NAME("TSS"); -__KERNEL_META("$Hyra$: tss.c, Ian Marco Moffett, " - "AMD64 Task state segment code"); - -static void -alloc_resources(struct cpu_info *cpu) -{ - struct tss_entry *tss; - - /* - * Allocate TSS entries for this CPU - */ - if (cpu->tss == NULL) { - /* Allocate a TSS for this CPU */ - tss = dynalloc(sizeof(*tss)); - if (tss == NULL) - panic("Failed to alloc %d bytes for TSS\n", sizeof(*tss)); - memset(tss, 0, sizeof(*tss)); - cpu->tss = tss; - } -} - -/* - * Update interrupt stack table entry `istno' with `stack' - * - * @stack: Interrupt stack. - * @istno: IST number, must be 1-based. - * - * Returns 0 on success. - */ -int -tss_update_ist(struct cpu_info *ci, union tss_stack stack, uint8_t istno) -{ - volatile struct tss_entry *tss = ci->tss; - - __assert(tss != NULL); - - switch (istno) { - case 1: - tss->ist1_lo = stack.top_lo; - tss->ist1_hi = stack.top_hi; - break; - case 2: - tss->ist2_lo = stack.top_lo; - tss->ist2_hi = stack.top_hi; - break; - case 3: - tss->ist3_lo = stack.top_lo; - tss->ist3_hi = stack.top_hi; - break; - case 4: - tss->ist4_lo = stack.top_lo; - tss->ist4_hi = stack.top_hi; - break; - case 5: - tss->ist5_lo = stack.top_lo; - tss->ist5_hi = stack.top_hi; - break; - case 6: - tss->ist6_lo = stack.top_lo; - tss->ist6_hi = stack.top_hi; - break; - case 7: - tss->ist7_lo = stack.top_lo; - tss->ist7_hi = stack.top_hi; - break; - default: - return -EXIT_FAILURE; - }; - - return 0; -} - -/* - * Allocates TSS stack. - * - * Returns 0 on success. - * - * @entry_out: Pointer to location where allocated entry - * will be sent. - */ -int -tss_alloc_stack(union tss_stack *entry_out, size_t size) -{ - uintptr_t base = (uintptr_t)dynalloc(size); - - if (base == 0) { - return -EXIT_FAILURE; - } - - entry_out->top = base + size; - return 0; -} - -void -write_tss(struct cpu_info *cpu, struct tss_desc *desc) -{ - uintptr_t tss_base; - - alloc_resources(cpu); - - tss_base = (uintptr_t)cpu->tss; - - /* - * XXX: The AVL (Available for use by system software) - * bit is ignored by hardware and it is up to us - * to decide how to use it... As of now, it is useless - * to us and shall remain 0. - */ - desc->seglimit = sizeof(struct tss_entry); - desc->p = 1; /* Must be present to be valid! */ - desc->g = 0; /* Granularity -> 0 */ - desc->avl = 0; /* Not used */ - desc->dpl = 0; /* Descriptor Privilege Level -> 0 */ - desc->type = 0x9; /* For TSS -> 0x9 (0b1001) */ - - desc->base_lo16 = __SHIFTOUT(tss_base, __MASK(16)); - desc->base_mid8 = __SHIFTOUT(tss_base, __MASK(8) << 16); - desc->base_hi_mid8 = __SHIFTOUT(tss_base, __MASK(8) << 24); - desc->base_hi32 = __SHIFTOUT(tss_base, __MASK(32) << 32); -} |