xref: /haiku/src/system/kernel/arch/ppc/arch_cpu.cpp (revision badc7b674eca3e33d1c5f865a626966110790f8f)
1 /*
2  * Copyright 2003-2005, Axel Dörfler, axeld@pinc-software.de.
3  * Distributed under the terms of the MIT License.
4  *
5  * Copyright 2001, Travis Geiselbrecht. All rights reserved.
6  * Distributed under the terms of the NewOS License.
7  */
8 
9 
10 #include <KernelExport.h>
11 
12 #include <arch_platform.h>
13 #include <arch_thread.h>
14 #include <arch/cpu.h>
15 #include <boot/kernel_args.h>
16 
17 static bool sHasTlbia;
18 
19 status_t
20 arch_cpu_preboot_init_percpu(kernel_args *args, int curr_cpu)
21 {
22 	// enable FPU
23 	set_msr(get_msr() | MSR_FP_AVAILABLE);
24 
25 	// The current thread must be NULL for all CPUs till we have threads.
26 	// Some boot code relies on this.
27 	arch_thread_set_current_thread(NULL);
28 
29 	return B_OK;
30 }
31 
32 
33 status_t
34 arch_cpu_init(kernel_args *args)
35 {
36 	// TODO: Let the boot loader put that info into the kernel args
37 	// (property "tlbia" in the CPU node).
38 	sHasTlbia = false;
39 
40 	return B_OK;
41 }
42 
43 
44 status_t
45 arch_cpu_init_post_vm(kernel_args *args)
46 {
47 	return B_OK;
48 }
49 
50 status_t
51 arch_cpu_init_post_modules(kernel_args *args)
52 {
53 	return B_OK;
54 }
55 
56 #define CACHELINE 32
57 
58 void
59 arch_cpu_sync_icache(void *address, size_t len)
60 {
61 	int l, off;
62 	char *p;
63 
64 	off = (unsigned int)address & (CACHELINE - 1);
65 	len += off;
66 
67 	l = len;
68 	p = (char *)address - off;
69 	do {
70 		asm volatile ("dcbst 0,%0" :: "r"(p));
71 		p += CACHELINE;
72 	} while ((l -= CACHELINE) > 0);
73 	asm volatile ("sync");
74 
75 	p = (char *)address - off;
76 	do {
77 		asm volatile ("icbi 0,%0" :: "r"(p));
78 		p += CACHELINE;
79 	} while ((len -= CACHELINE) > 0);
80 	asm volatile ("sync");
81 	isync();
82 }
83 
84 
85 void
86 arch_cpu_invalidate_TLB_range(addr_t start, addr_t end)
87 {
88 	asm volatile("sync");
89 	while (start < end) {
90 		asm volatile("tlbie %0" :: "r" (start));
91 		asm volatile("eieio");
92 		asm volatile("sync");
93 		start += B_PAGE_SIZE;
94 	}
95 	asm volatile("tlbsync");
96 	asm volatile("sync");
97 }
98 
99 
100 void
101 arch_cpu_invalidate_TLB_list(addr_t pages[], int num_pages)
102 {
103 	int i;
104 
105 	asm volatile("sync");
106 	for (i = 0; i < num_pages; i++) {
107 		asm volatile("tlbie %0" :: "r" (pages[i]));
108 		asm volatile("eieio");
109 		asm volatile("sync");
110 	}
111 	asm volatile("tlbsync");
112 	asm volatile("sync");
113 }
114 
115 
116 void
117 arch_cpu_global_TLB_invalidate(void)
118 {
119 	if (sHasTlbia) {
120 		ppc_sync();
121 		tlbia();
122 		ppc_sync();
123 	} else {
124 		addr_t address = 0;
125 		unsigned long i;
126 
127 		ppc_sync();
128 		for (i = 0; i < 0x100000; i++) {
129 			tlbie(address);
130 			eieio();
131 			ppc_sync();
132 
133 			address += B_PAGE_SIZE;
134 		}
135 		tlbsync();
136 		ppc_sync();
137 	}
138 }
139 
140 
141 void
142 arch_cpu_user_TLB_invalidate(void)
143 {
144 	arch_cpu_global_TLB_invalidate();
145 }
146 
147 
148 status_t
149 arch_cpu_user_memcpy(void *to, const void *from, size_t size,
150 	addr_t *faultHandler)
151 {
152 	char *tmp = (char *)to;
153 	char *s = (char *)from;
154 
155 	if (ppc_set_fault_handler(faultHandler, (addr_t)&&error))
156 		goto error;
157 
158 	while (size--)
159 		*tmp++ = *s++;
160 
161 	*faultHandler = 0;
162 	return 0;
163 
164 error:
165 	*faultHandler = 0;
166 	return B_BAD_ADDRESS;
167 }
168 
169 
170 /**	\brief Copies at most (\a size - 1) characters from the string in \a from to
171  *	the string in \a to, NULL-terminating the result.
172  *
173  *	\param to Pointer to the destination C-string.
174  *	\param from Pointer to the source C-string.
175  *	\param size Size in bytes of the string buffer pointed to by \a to.
176  *
177  *	\return strlen(\a from).
178  */
179 
180 ssize_t
181 arch_cpu_user_strlcpy(char *to, const char *from, size_t size, addr_t *faultHandler)
182 {
183 	int from_length = 0;
184 
185 	if (ppc_set_fault_handler(faultHandler, (addr_t)&&error))
186 		goto error;
187 
188 	if (size > 0) {
189 		to[--size] = '\0';
190 		// copy
191 		for ( ; size; size--, from_length++, to++, from++) {
192 			if ((*to = *from) == '\0')
193 				break;
194 		}
195 	}
196 	// count any leftover from chars
197 	while (*from++ != '\0')
198 		from_length++;
199 
200 	*faultHandler = 0;
201 	return from_length;
202 
203 error:
204 	*faultHandler = 0;
205 	return B_BAD_ADDRESS;
206 }
207 
208 
209 status_t
210 arch_cpu_user_memset(void *s, char c, size_t count, addr_t *faultHandler)
211 {
212 	char *xs = (char *)s;
213 
214 	if (ppc_set_fault_handler(faultHandler, (addr_t)&&error))
215 		goto error;
216 
217 	while (count--)
218 		*xs++ = c;
219 
220 	*faultHandler = 0;
221 	return 0;
222 
223 error:
224 	*faultHandler = 0;
225 	return B_BAD_ADDRESS;
226 }
227 
228 
229 status_t
230 arch_cpu_shutdown(bool reboot)
231 {
232 	PPCPlatform::Default()->ShutDown(reboot);
233 	return B_ERROR;
234 }
235 
236 
237 void
238 arch_cpu_idle(void)
239 {
240 }
241 
242 
243 // The purpose of this function is to trick the compiler. When setting the
244 // page_handler to a label that is obviously (to the compiler) never used,
245 // it may reorganize the control flow, so that the labeled part is optimized
246 // away.
247 // By invoking the function like this
248 //
249 //	if (ppc_set_fault_handler(faultHandler, (addr_t)&&error))
250 //		goto error;
251 //
252 // the compiler has to keep the labeled code, since it can't guess the return
253 // value of this (non-inlinable) function. At least in my tests it worked that
254 // way, and I hope it will continue to work like this in the future.
255 //
256 bool
257 ppc_set_fault_handler(addr_t *handlerLocation, addr_t handler)
258 {
259 	*handlerLocation = handler;
260 	return false;
261 }
262