--- /dev/null
+#ifndef __SPARC_SWITCH_TO_H
+#define __SPARC_SWITCH_TO_H
+
+#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)
+
+void fpsave(unsigned long *fpregs, unsigned long *fsr,
+ void *fpqueue, unsigned long *fpqdepth);
+void synchronize_user_stack(void);
+
+#endif /* __SPARC_SWITCH_TO_H */
Code Review / kvmfornfv.git / blobdiff