107 lines
		
	
	
	
		
			3.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			107 lines
		
	
	
	
		
			3.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | #ifndef __SPARC_SWITCH_TO_H
 | ||
|  | #define __SPARC_SWITCH_TO_H
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|  | 
 | ||
|  | #include <asm/smp.h>
 | ||
|  | 
 | ||
|  | extern struct thread_info *current_set[NR_CPUS]; | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Flush windows so that the VM switch which follows | ||
|  |  * would not pull the stack from under us. | ||
|  |  * | ||
|  |  * SWITCH_ENTER and SWITH_DO_LAZY_FPU do not work yet (e.g. SMP does not work) | ||
|  |  * XXX WTF is the above comment? Found in late teen 2.4.x. | ||
|  |  */ | ||
|  | #ifdef CONFIG_SMP
 | ||
|  | #define SWITCH_ENTER(prv) \
 | ||
|  | 	do {			\ | ||
|  | 	if (test_tsk_thread_flag(prv, TIF_USEDFPU)) { \ | ||
|  | 		put_psr(get_psr() | PSR_EF); \ | ||
|  | 		fpsave(&(prv)->thread.float_regs[0], &(prv)->thread.fsr, \ | ||
|  | 		       &(prv)->thread.fpqueue[0], &(prv)->thread.fpqdepth); \ | ||
|  | 		clear_tsk_thread_flag(prv, TIF_USEDFPU); \ | ||
|  | 		(prv)->thread.kregs->psr &= ~PSR_EF; \ | ||
|  | 	} \ | ||
|  | 	} while(0) | ||
|  | 
 | ||
|  | #define SWITCH_DO_LAZY_FPU(next)	/* */
 | ||
|  | #else
 | ||
|  | #define SWITCH_ENTER(prv)		/* */
 | ||
|  | #define SWITCH_DO_LAZY_FPU(nxt)	\
 | ||
|  | 	do {			\ | ||
|  | 	if (last_task_used_math != (nxt))		\ | ||
|  | 		(nxt)->thread.kregs->psr&=~PSR_EF;	\ | ||
|  | 	} while(0) | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #define prepare_arch_switch(next) do { \
 | ||
|  | 	__asm__ __volatile__( \ | ||
|  | 	".globl\tflush_patch_switch\nflush_patch_switch:\n\t" \ | ||
|  | 	"save %sp, -0x40, %sp; save %sp, -0x40, %sp; save %sp, -0x40, %sp\n\t" \ | ||
|  | 	"save %sp, -0x40, %sp; save %sp, -0x40, %sp; save %sp, -0x40, %sp\n\t" \ | ||
|  | 	"save %sp, -0x40, %sp\n\t" \ | ||
|  | 	"restore; restore; restore; restore; restore; restore; restore"); \ | ||
|  | } while(0) | ||
|  | 
 | ||
|  | 	/* Much care has gone into this code, do not touch it.
 | ||
|  | 	 * | ||
|  | 	 * We need to loadup regs l0/l1 for the newly forked child | ||
|  | 	 * case because the trap return path relies on those registers | ||
|  | 	 * holding certain values, gcc is told that they are clobbered. | ||
|  | 	 * Gcc needs registers for 3 values in and 1 value out, so we | ||
|  | 	 * clobber every non-fixed-usage register besides l2/l3/o4/o5.  -DaveM | ||
|  | 	 * | ||
|  | 	 * Hey Dave, that do not touch sign is too much of an incentive | ||
|  | 	 * - Anton & Pete | ||
|  | 	 */ | ||
|  | #define switch_to(prev, next, last) do {						\
 | ||
|  | 	SWITCH_ENTER(prev);								\ | ||
|  | 	SWITCH_DO_LAZY_FPU(next);							\ | ||
|  | 	cpumask_set_cpu(smp_processor_id(), mm_cpumask(next->active_mm));		\ | ||
|  | 	__asm__ __volatile__(								\ | ||
|  | 	"sethi	%%hi(here - 0x8), %%o7\n\t"						\ | ||
|  | 	"mov	%%g6, %%g3\n\t"								\ | ||
|  | 	"or	%%o7, %%lo(here - 0x8), %%o7\n\t"					\ | ||
|  | 	"rd	%%psr, %%g4\n\t"							\ | ||
|  | 	"std	%%sp, [%%g6 + %4]\n\t"							\ | ||
|  | 	"rd	%%wim, %%g5\n\t"							\ | ||
|  | 	"wr	%%g4, 0x20, %%psr\n\t"							\ | ||
|  | 	"nop\n\t"									\ | ||
|  | 	"std	%%g4, [%%g6 + %3]\n\t"							\ | ||
|  | 	"ldd	[%2 + %3], %%g4\n\t"							\ | ||
|  | 	"mov	%2, %%g6\n\t"								\ | ||
|  | 	".globl	patchme_store_new_current\n"						\ | ||
|  | "patchme_store_new_current:\n\t"							\ | ||
|  | 	"st	%2, [%1]\n\t"								\ | ||
|  | 	"wr	%%g4, 0x20, %%psr\n\t"							\ | ||
|  | 	"nop\n\t"									\ | ||
|  | 	"nop\n\t"									\ | ||
|  | 	"nop\n\t"	/* LEON needs all 3 nops: load to %sp depends on CWP. */		\ | ||
|  | 	"ldd	[%%g6 + %4], %%sp\n\t"							\ | ||
|  | 	"wr	%%g5, 0x0, %%wim\n\t"							\ | ||
|  | 	"ldd	[%%sp + 0x00], %%l0\n\t"						\ | ||
|  | 	"ldd	[%%sp + 0x38], %%i6\n\t"						\ | ||
|  | 	"wr	%%g4, 0x0, %%psr\n\t"							\ | ||
|  | 	"nop\n\t"									\ | ||
|  | 	"nop\n\t"									\ | ||
|  | 	"jmpl	%%o7 + 0x8, %%g0\n\t"							\ | ||
|  | 	" ld	[%%g3 + %5], %0\n\t"							\ | ||
|  | 	"here:\n"									\ | ||
|  |         : "=&r" (last)									\ | ||
|  |         : "r" (&(current_set[hard_smp_processor_id()])),	\ | ||
|  | 	  "r" (task_thread_info(next)),				\ | ||
|  | 	  "i" (TI_KPSR),					\ | ||
|  | 	  "i" (TI_KSP),						\ | ||
|  | 	  "i" (TI_TASK)						\ | ||
|  | 	:       "g1", "g2", "g3", "g4", "g5",       "g7",	\ | ||
|  | 	  "l0", "l1",       "l3", "l4", "l5", "l6", "l7",	\ | ||
|  | 	  "i0", "i1", "i2", "i3", "i4", "i5",			\ | ||
|  | 	  "o0", "o1", "o2", "o3",                   "o7");	\ | ||
|  | 	} while(0) | ||
|  | 
 | ||
|  | extern void fpsave(unsigned long *fpregs, unsigned long *fsr, | ||
|  | 		   void *fpqueue, unsigned long *fpqdepth); | ||
|  | extern void synchronize_user_stack(void); | ||
|  | 
 | ||
|  | #endif /* __SPARC_SWITCH_TO_H */
 |