1 /*
2 * Copyright 2021-2022 Haiku, Inc. All rights reserved.
3 * Released under the terms of the MIT License.
4 *
5 * Copyright 2008, Dustin Howett, dustin.howett@gmail.com. All rights reserved.
6 * Copyright 2004-2010, Axel Dörfler, axeld@pinc-software.de.
7 * Distributed under the terms of the MIT License.
8 *
9 * Copyright 2001, Travis Geiselbrecht. All rights reserved.
10 * Distributed under the terms of the NewOS License.
11 */
12
13
14 #include "arch_smp.h"
15
16 #include <boot/stage2.h>
17
18
19 //#define TRACE_SMP
20 #ifdef TRACE_SMP
21 # define TRACE(x...) dprintf(x)
22 #else
23 # define TRACE(x...) ;
24 #endif
25
26
27 extern "C" void long_smp_trampoline(void);
28 extern "C" void long_smp_trampoline_args(void);
29 extern "C" void long_smp_trampoline_end(void);
30 extern "C" uint64 gLongGDTR;
31
32 struct gdtr {
33 uint16 limit;
34 uint32 base;
35 unsigned char null[8];
36 unsigned char code[8];
37 unsigned char data[8];
38 } __attribute__((packed));
39
40 // Arguments passed to the SMP trampoline.
41 struct long_trampoline_args {
42 uint32 trampoline; // Trampoline address
43 uint32 gdt32; // 32-bit GDTR
44 uint32 pml4; // 64-bit PML4
45 uint32 gdt64; // 64-bit GDTR
46 uint64 kernel_entry; // Kernel entry point
47 uint64 kernel_args; // Kernel arguments
48 uint64 current_cpu; // CPU number
49 uint64 stack_top; // Kernel stack
50 volatile uint64 sentinel; // Sentinel, AP sets to 0 when finished
51
52 // smp_boot_other_cpus puts the GDTR here.
53 struct gdtr gdtr;
54 };
55
56
57 void
copy_trampoline_code(uint64 trampolineCode,uint64 trampolineStack)58 copy_trampoline_code(uint64 trampolineCode, uint64 trampolineStack)
59 {
60 TRACE("copying the trampoline code to %p from %p\n", (char*)trampolineCode, (const void*)&long_smp_trampoline);
61 TRACE("size of trampoline code = %" PRIu64 " bytes\n", (uint64)&long_smp_trampoline_end - (uint64)&long_smp_trampoline);
62 memcpy((char *)trampolineCode, (const void*)&long_smp_trampoline,
63 (uint64)&long_smp_trampoline_end - (uint64)&long_smp_trampoline);
64 }
65
66
67 void
prepare_trampoline_args(uint64 trampolineCode,uint64 trampolineStack,uint32 pagedir,uint64 kernelEntry,addr_t virtKernelArgs,uint32 currentCpu)68 prepare_trampoline_args(uint64 trampolineCode, uint64 trampolineStack,
69 uint32 pagedir, uint64 kernelEntry, addr_t virtKernelArgs,
70 uint32 currentCpu)
71 {
72 long_trampoline_args* args = (long_trampoline_args *)trampolineStack;
73 args->trampoline = trampolineCode;
74
75 args->gdt32 = (uint64) &args->gdtr;
76 args->gdtr.limit = 23;
77 args->gdtr.base = (uint32)(uint64)args->gdtr.null;
78 #define COPY_ARRAY(A, X0, X1, X2, X3, X4, X5, X6, X7) \
79 { A[0] = X0; A[1] = X1; A[2] = X2; A[3] = X3; A[4] = X4; A[5] = X5; A[6] = X6; A[7] = X7; }
80 COPY_ARRAY(args->gdtr.null, 0, 0, 0, 0, 0, 0, 0, 0);
81 COPY_ARRAY(args->gdtr.code, 0xff, 0xff, 0, 0, 0, 0x9a, 0xcf, 0);
82 COPY_ARRAY(args->gdtr.data, 0xff, 0xff, 0, 0, 0, 0x92, 0xcf, 0);
83 #undef COPY_ARRAY
84 args->gdt64 = (uint32_t)(uint64_t)&gLongGDTR;
85
86 args->pml4 = pagedir;
87 args->kernel_entry = kernelEntry;
88 args->kernel_args = virtKernelArgs;
89 args->current_cpu = currentCpu;
90 args->stack_top = gKernelArgs.cpu_kstack[currentCpu].start
91 + gKernelArgs.cpu_kstack[currentCpu].size;
92 args->sentinel = 1;
93
94 // put the args in the right place
95 uint32 * args_ptr =
96 (uint32 *)(trampolineCode + (uint64)long_smp_trampoline_args - (uint64)long_smp_trampoline);
97 *args_ptr = (uint32)trampolineStack;
98 }
99
100
101 uint32
get_sentinel(uint64 trampolineStack)102 get_sentinel(uint64 trampolineStack)
103 {
104 long_trampoline_args* args = (long_trampoline_args *)trampolineStack;
105 return args->sentinel;
106 }
107