V4L/DVB (7069): Support for myTV.t
[linux-2.6] / include / asm-sparc / system.h
1 #ifndef __SPARC_SYSTEM_H
2 #define __SPARC_SYSTEM_H
3
4 #include <linux/kernel.h>
5 #include <linux/threads.h>      /* NR_CPUS */
6 #include <linux/thread_info.h>
7
8 #include <asm/page.h>
9 #include <asm/psr.h>
10 #include <asm/ptrace.h>
11 #include <asm/btfixup.h>
12 #include <asm/smp.h>
13
14 #ifndef __ASSEMBLY__
15
16 #include <linux/irqflags.h>
17
18 /*
19  * Sparc (general) CPU types
20  */
21 enum sparc_cpu {
22   sun4        = 0x00,
23   sun4c       = 0x01,
24   sun4m       = 0x02,
25   sun4d       = 0x03,
26   sun4e       = 0x04,
27   sun4u       = 0x05, /* V8 ploos ploos */
28   sun_unknown = 0x06,
29   ap1000      = 0x07, /* almost a sun4m */
30 };
31
32 /* Really, userland should not be looking at any of this... */
33 #ifdef __KERNEL__
34
35 extern enum sparc_cpu sparc_cpu_model;
36
37 #ifndef CONFIG_SUN4
38 #define ARCH_SUN4C_SUN4 (sparc_cpu_model==sun4c)
39 #define ARCH_SUN4 0
40 #else
41 #define ARCH_SUN4C_SUN4 1
42 #define ARCH_SUN4 1
43 #endif
44
45 #define SUN4M_NCPUS            4              /* Architectural limit of sun4m. */
46
47 extern struct thread_info *current_set[NR_CPUS];
48
49 extern unsigned long empty_bad_page;
50 extern unsigned long empty_bad_page_table;
51 extern unsigned long empty_zero_page;
52
53 extern void sun_do_break(void);
54 extern int serial_console;
55 extern int stop_a_enabled;
56
57 static inline int con_is_present(void)
58 {
59         return serial_console ? 0 : 1;
60 }
61
62 /* When a context switch happens we must flush all user windows so that
63  * the windows of the current process are flushed onto its stack. This
64  * way the windows are all clean for the next process and the stack
65  * frames are up to date.
66  */
67 extern void flush_user_windows(void);
68 extern void kill_user_windows(void);
69 extern void synchronize_user_stack(void);
70 extern void fpsave(unsigned long *fpregs, unsigned long *fsr,
71                    void *fpqueue, unsigned long *fpqdepth);
72
73 #ifdef CONFIG_SMP
74 #define SWITCH_ENTER(prv) \
75         do {                    \
76         if (test_tsk_thread_flag(prv, TIF_USEDFPU)) { \
77                 put_psr(get_psr() | PSR_EF); \
78                 fpsave(&(prv)->thread.float_regs[0], &(prv)->thread.fsr, \
79                        &(prv)->thread.fpqueue[0], &(prv)->thread.fpqdepth); \
80                 clear_tsk_thread_flag(prv, TIF_USEDFPU); \
81                 (prv)->thread.kregs->psr &= ~PSR_EF; \
82         } \
83         } while(0)
84
85 #define SWITCH_DO_LAZY_FPU(next)        /* */
86 #else
87 #define SWITCH_ENTER(prv)               /* */
88 #define SWITCH_DO_LAZY_FPU(nxt) \
89         do {                    \
90         if (last_task_used_math != (nxt))               \
91                 (nxt)->thread.kregs->psr&=~PSR_EF;      \
92         } while(0)
93 #endif
94
95 /*
96  * Flush windows so that the VM switch which follows
97  * would not pull the stack from under us.
98  *
99  * SWITCH_ENTER and SWITH_DO_LAZY_FPU do not work yet (e.g. SMP does not work)
100  * XXX WTF is the above comment? Found in late teen 2.4.x.
101  */
102 #define prepare_arch_switch(next) do { \
103         __asm__ __volatile__( \
104         ".globl\tflush_patch_switch\nflush_patch_switch:\n\t" \
105         "save %sp, -0x40, %sp; save %sp, -0x40, %sp; save %sp, -0x40, %sp\n\t" \
106         "save %sp, -0x40, %sp; save %sp, -0x40, %sp; save %sp, -0x40, %sp\n\t" \
107         "save %sp, -0x40, %sp\n\t" \
108         "restore; restore; restore; restore; restore; restore; restore"); \
109 } while(0)
110
111         /* Much care has gone into this code, do not touch it.
112          *
113          * We need to loadup regs l0/l1 for the newly forked child
114          * case because the trap return path relies on those registers
115          * holding certain values, gcc is told that they are clobbered.
116          * Gcc needs registers for 3 values in and 1 value out, so we
117          * clobber every non-fixed-usage register besides l2/l3/o4/o5.  -DaveM
118          *
119          * Hey Dave, that do not touch sign is too much of an incentive
120          * - Anton & Pete
121          */
122 #define switch_to(prev, next, last) do {                                                \
123         SWITCH_ENTER(prev);                                                             \
124         SWITCH_DO_LAZY_FPU(next);                                                       \
125         cpu_set(smp_processor_id(), next->active_mm->cpu_vm_mask);                      \
126         __asm__ __volatile__(                                                           \
127         "sethi  %%hi(here - 0x8), %%o7\n\t"                                             \
128         "mov    %%g6, %%g3\n\t"                                                         \
129         "or     %%o7, %%lo(here - 0x8), %%o7\n\t"                                       \
130         "rd     %%psr, %%g4\n\t"                                                        \
131         "std    %%sp, [%%g6 + %4]\n\t"                                                  \
132         "rd     %%wim, %%g5\n\t"                                                        \
133         "wr     %%g4, 0x20, %%psr\n\t"                                                  \
134         "nop\n\t"                                                                       \
135         "std    %%g4, [%%g6 + %3]\n\t"                                                  \
136         "ldd    [%2 + %3], %%g4\n\t"                                                    \
137         "mov    %2, %%g6\n\t"                                                           \
138         ".globl patchme_store_new_current\n"                                            \
139 "patchme_store_new_current:\n\t"                                                        \
140         "st     %2, [%1]\n\t"                                                           \
141         "wr     %%g4, 0x20, %%psr\n\t"                                                  \
142         "nop\n\t"                                                                       \
143         "nop\n\t"                                                                       \
144         "nop\n\t"       /* LEON needs all 3 nops: load to %sp depends on CWP. */                \
145         "ldd    [%%g6 + %4], %%sp\n\t"                                                  \
146         "wr     %%g5, 0x0, %%wim\n\t"                                                   \
147         "ldd    [%%sp + 0x00], %%l0\n\t"                                                \
148         "ldd    [%%sp + 0x38], %%i6\n\t"                                                \
149         "wr     %%g4, 0x0, %%psr\n\t"                                                   \
150         "nop\n\t"                                                                       \
151         "nop\n\t"                                                                       \
152         "jmpl   %%o7 + 0x8, %%g0\n\t"                                                   \
153         " ld    [%%g3 + %5], %0\n\t"                                                    \
154         "here:\n"                                                                       \
155         : "=&r" (last)                                                                  \
156         : "r" (&(current_set[hard_smp_processor_id()])),        \
157           "r" (task_thread_info(next)),                         \
158           "i" (TI_KPSR),                                        \
159           "i" (TI_KSP),                                         \
160           "i" (TI_TASK)                                         \
161         :       "g1", "g2", "g3", "g4", "g5",       "g7",       \
162           "l0", "l1",       "l3", "l4", "l5", "l6", "l7",       \
163           "i0", "i1", "i2", "i3", "i4", "i5",                   \
164           "o0", "o1", "o2", "o3",                   "o7");      \
165         } while(0)
166
167 /* XXX Change this if we ever use a PSO mode kernel. */
168 #define mb()    __asm__ __volatile__ ("" : : : "memory")
169 #define rmb()   mb()
170 #define wmb()   mb()
171 #define read_barrier_depends()  do { } while(0)
172 #define set_mb(__var, __value)  do { __var = __value; mb(); } while(0)
173 #define smp_mb()        __asm__ __volatile__("":::"memory")
174 #define smp_rmb()       __asm__ __volatile__("":::"memory")
175 #define smp_wmb()       __asm__ __volatile__("":::"memory")
176 #define smp_read_barrier_depends()      do { } while(0)
177
178 #define nop() __asm__ __volatile__ ("nop")
179
180 /* This has special calling conventions */
181 #ifndef CONFIG_SMP
182 BTFIXUPDEF_CALL(void, ___xchg32, void)
183 #endif
184
185 static inline unsigned long xchg_u32(__volatile__ unsigned long *m, unsigned long val)
186 {
187 #ifdef CONFIG_SMP
188         __asm__ __volatile__("swap [%2], %0"
189                              : "=&r" (val)
190                              : "0" (val), "r" (m)
191                              : "memory");
192         return val;
193 #else
194         register unsigned long *ptr asm("g1");
195         register unsigned long ret asm("g2");
196
197         ptr = (unsigned long *) m;
198         ret = val;
199
200         /* Note: this is magic and the nop there is
201            really needed. */
202         __asm__ __volatile__(
203         "mov    %%o7, %%g4\n\t"
204         "call   ___f____xchg32\n\t"
205         " nop\n\t"
206         : "=&r" (ret)
207         : "0" (ret), "r" (ptr)
208         : "g3", "g4", "g7", "memory", "cc");
209
210         return ret;
211 #endif
212 }
213
214 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
215
216 extern void __xchg_called_with_bad_pointer(void);
217
218 static inline unsigned long __xchg(unsigned long x, __volatile__ void * ptr, int size)
219 {
220         switch (size) {
221         case 4:
222                 return xchg_u32(ptr, x);
223         };
224         __xchg_called_with_bad_pointer();
225         return x;
226 }
227
228 extern void die_if_kernel(char *str, struct pt_regs *regs) __attribute__ ((noreturn));
229
230 #endif /* __KERNEL__ */
231
232 #endif /* __ASSEMBLY__ */
233
234 #define arch_align_stack(x) (x)
235
236 #endif /* !(__SPARC_SYSTEM_H) */