2 * Copyright (C) 2005,2006,2007,2008,2009,2010,2011 Imagination Technologies
4 * This file contains the architecture-dependent parts of process handling.
8 #include <linux/errno.h>
9 #include <linux/export.h>
10 #include <linux/sched.h>
11 #include <linux/kernel.h>
13 #include <linux/unistd.h>
14 #include <linux/ptrace.h>
15 #include <linux/user.h>
16 #include <linux/reboot.h>
17 #include <linux/elfcore.h>
19 #include <linux/tick.h>
20 #include <linux/slab.h>
21 #include <linux/mman.h>
23 #include <linux/syscalls.h>
24 #include <linux/uaccess.h>
25 #include <linux/smp.h>
26 #include <asm/core_reg.h>
27 #include <asm/user_gateway.h>
29 #include <asm/traps.h>
30 #include <asm/switch_to.h>
33 * Wait for the next interrupt and enable local interrupts
35 void arch_cpu_idle(void)
40 * Quickly jump straight into the interrupt entry point without actually
41 * triggering an interrupt. When TXSTATI gets read the processor will
42 * block until an interrupt is triggered.
44 asm volatile (/* Switch into ISTAT mode */
46 /* Enable local interrupts */
49 * We can't directly "SWAP PC, PCX", so we swap via a
50 * temporary. Essentially we do:
51 * PCX_new = 1f (the place to continue execution)
54 "ADD %0, CPC0, #(1f-.)\n\t"
57 /* Continue execution here with interrupts enabled */
60 : "r" (get_trigger_mask()));
63 #ifdef CONFIG_HOTPLUG_CPU
64 void arch_cpu_idle_dead(void)
70 void (*pm_power_off)(void);
71 EXPORT_SYMBOL(pm_power_off);
73 void (*soc_restart)(char *cmd);
74 void (*soc_halt)(void);
76 void machine_restart(char *cmd)
80 hard_processor_halt(HALT_OK);
83 void machine_halt(void)
88 hard_processor_halt(HALT_OK);
91 void machine_power_off(void)
96 hard_processor_halt(HALT_OK);
104 void show_regs(struct pt_regs *regs)
107 const char *AX0_names[] = {"A0StP", "A0FrP"};
108 const char *AX1_names[] = {"A1GbP", "A1LbP"};
110 const char *DX0_names[] = {
121 const char *DX1_names[] = {
132 show_regs_print_info(KERN_INFO);
134 pr_info(" pt_regs @ %p\n", regs);
135 pr_info(" SaveMask = 0x%04hx\n", regs->ctx.SaveMask);
136 pr_info(" Flags = 0x%04hx (%c%c%c%c)\n", regs->ctx.Flags,
137 regs->ctx.Flags & FLAG_Z ? 'Z' : 'z',
138 regs->ctx.Flags & FLAG_N ? 'N' : 'n',
139 regs->ctx.Flags & FLAG_O ? 'O' : 'o',
140 regs->ctx.Flags & FLAG_C ? 'C' : 'c');
141 pr_info(" TXRPT = 0x%08x\n", regs->ctx.CurrRPT);
142 pr_info(" PC = 0x%08x\n", regs->ctx.CurrPC);
145 for (i = 0; i < 2; i++) {
146 pr_info(" %s = 0x%08x ",
149 printk(" %s = 0x%08x\n",
154 if (regs->ctx.SaveMask & TBICTX_XEXT_BIT)
155 pr_warn(" Extended state present - AX2.[01] will be WRONG\n");
157 /* Special place with AXx.2 */
158 pr_info(" A0.2 = 0x%08x ",
159 regs->ctx.Ext.AX2.U0);
160 printk(" A1.2 = 0x%08x\n",
161 regs->ctx.Ext.AX2.U1);
163 /* 'extended' AX regs (nominally, just AXx.3) */
164 for (i = 0; i < (TBICTX_AX_REGS - 3); i++) {
165 pr_info(" A0.%d = 0x%08x ", i + 3, regs->ctx.AX3[i].U0);
166 printk(" A1.%d = 0x%08x\n", i + 3, regs->ctx.AX3[i].U1);
169 for (i = 0; i < 8; i++) {
170 pr_info(" %s = 0x%08x ", DX0_names[i], regs->ctx.DX[i].U0);
171 printk(" %s = 0x%08x\n", DX1_names[i], regs->ctx.DX[i].U1);
174 show_trace(NULL, (unsigned long *)regs->ctx.AX[0].U0, regs);
177 int copy_thread(unsigned long clone_flags, unsigned long usp,
178 unsigned long arg, struct task_struct *tsk)
180 struct pt_regs *childregs = task_pt_regs(tsk);
181 void *kernel_context = ((void *) childregs +
182 sizeof(struct pt_regs));
183 unsigned long global_base;
185 BUG_ON(((unsigned long)childregs) & 0x7);
186 BUG_ON(((unsigned long)kernel_context) & 0x7);
188 memset(&tsk->thread.kernel_context, 0,
189 sizeof(tsk->thread.kernel_context));
191 tsk->thread.kernel_context = __TBISwitchInit(kernel_context,
195 if (unlikely(tsk->flags & PF_KTHREAD)) {
197 * Make sure we don't leak any kernel data to child's regs
198 * if kernel thread becomes a userspace thread in the future
200 memset(childregs, 0 , sizeof(struct pt_regs));
202 global_base = __core_reg_get(A1GbP);
203 childregs->ctx.AX[0].U1 = (unsigned long) global_base;
204 childregs->ctx.AX[0].U0 = (unsigned long) kernel_context;
205 /* Set D1Ar1=arg and D1RtP=usp (fn) */
206 childregs->ctx.DX[4].U1 = usp;
207 childregs->ctx.DX[3].U1 = arg;
208 tsk->thread.int_depth = 2;
212 * Get a pointer to where the new child's register block should have
214 * The Meta's stack grows upwards, and the context is the the first
215 * thing to be pushed by TBX (phew)
217 *childregs = *current_pt_regs();
218 /* Set the correct stack for the clone mode */
220 childregs->ctx.AX[0].U0 = ALIGN(usp, 8);
221 tsk->thread.int_depth = 1;
223 /* set return value for child process */
224 childregs->ctx.DX[0].U0 = 0;
226 /* The TLS pointer is passed as an argument to sys_clone. */
227 if (clone_flags & CLONE_SETTLS)
228 tsk->thread.tls_ptr =
229 (__force void __user *)childregs->ctx.DX[1].U1;
231 #ifdef CONFIG_METAG_FPU
232 if (tsk->thread.fpu_context) {
233 struct meta_fpu_context *ctx;
235 ctx = kmemdup(tsk->thread.fpu_context,
236 sizeof(struct meta_fpu_context), GFP_ATOMIC);
237 tsk->thread.fpu_context = ctx;
241 #ifdef CONFIG_METAG_DSP
242 if (tsk->thread.dsp_context) {
243 struct meta_ext_context *ctx;
246 ctx = kmemdup(tsk->thread.dsp_context,
247 sizeof(struct meta_ext_context), GFP_ATOMIC);
248 for (i = 0; i < 2; i++)
249 ctx->ram[i] = kmemdup(ctx->ram[i], ctx->ram_sz[i],
251 tsk->thread.dsp_context = ctx;
258 #ifdef CONFIG_METAG_FPU
259 static void alloc_fpu_context(struct thread_struct *thread)
261 thread->fpu_context = kzalloc(sizeof(struct meta_fpu_context),
265 static void clear_fpu(struct thread_struct *thread)
267 thread->user_flags &= ~TBICTX_FPAC_BIT;
268 kfree(thread->fpu_context);
269 thread->fpu_context = NULL;
272 static void clear_fpu(struct thread_struct *thread)
277 #ifdef CONFIG_METAG_DSP
278 static void clear_dsp(struct thread_struct *thread)
280 if (thread->dsp_context) {
281 kfree(thread->dsp_context->ram[0]);
282 kfree(thread->dsp_context->ram[1]);
284 kfree(thread->dsp_context);
286 thread->dsp_context = NULL;
289 __core_reg_set(D0.8, 0);
292 static void clear_dsp(struct thread_struct *thread)
297 struct task_struct *__sched __switch_to(struct task_struct *prev,
298 struct task_struct *next)
302 to.Switch.pCtx = next->thread.kernel_context;
303 to.Switch.pPara = prev;
305 #ifdef CONFIG_METAG_FPU
306 if (prev->thread.user_flags & TBICTX_FPAC_BIT) {
307 struct pt_regs *regs = task_pt_regs(prev);
310 state.Sig.SaveMask = prev->thread.user_flags;
311 state.Sig.pCtx = ®s->ctx;
313 if (!prev->thread.fpu_context)
314 alloc_fpu_context(&prev->thread);
315 if (prev->thread.fpu_context)
316 __TBICtxFPUSave(state, prev->thread.fpu_context);
319 * Force a restore of the FPU context next time this process is
322 if (prev->thread.fpu_context)
323 prev->thread.fpu_context->needs_restore = true;
327 from = __TBISwitch(to, &prev->thread.kernel_context);
329 /* Restore TLS pointer for this process. */
330 set_gateway_tls(current->thread.tls_ptr);
332 return (struct task_struct *) from.Switch.pPara;
335 void flush_thread(void)
337 clear_fpu(¤t->thread);
338 clear_dsp(¤t->thread);
342 * Free current thread data structures etc.
344 void exit_thread(void)
346 clear_fpu(¤t->thread);
347 clear_dsp(¤t->thread);
350 /* TODO: figure out how to unwind the kernel stack here to figure out
351 * where we went to sleep. */
352 unsigned long get_wchan(struct task_struct *p)
357 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
359 /* Returning 0 indicates that the FPU state was not stored (as it was
364 #ifdef CONFIG_METAG_USER_TCM
366 #define ELF_MIN_ALIGN PAGE_SIZE
368 #define ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(ELF_MIN_ALIGN-1))
369 #define ELF_PAGEOFFSET(_v) ((_v) & (ELF_MIN_ALIGN-1))
370 #define ELF_PAGEALIGN(_v) (((_v) + ELF_MIN_ALIGN - 1) & ~(ELF_MIN_ALIGN - 1))
372 #define BAD_ADDR(x) ((unsigned long)(x) >= TASK_SIZE)
374 unsigned long __metag_elf_map(struct file *filep, unsigned long addr,
375 struct elf_phdr *eppnt, int prot, int type,
376 unsigned long total_size)
378 unsigned long map_addr, size;
379 unsigned long page_off = ELF_PAGEOFFSET(eppnt->p_vaddr);
380 unsigned long raw_size = eppnt->p_filesz + page_off;
381 unsigned long off = eppnt->p_offset - page_off;
382 unsigned int tcm_tag;
383 addr = ELF_PAGESTART(addr);
384 size = ELF_PAGEALIGN(raw_size);
386 /* mmap() will return -EINVAL if given a zero size, but a
387 * segment with zero filesize is perfectly valid */
391 tcm_tag = tcm_lookup_tag(addr);
393 if (tcm_tag != TCM_INVALID_TAG)
397 * total_size is the size of the ELF (interpreter) image.
398 * The _first_ mmap needs to know the full size, otherwise
399 * randomization might put this image into an overlapping
400 * position with the ELF binary image. (since size < total_size)
401 * So we first map the 'big' image - and unmap the remainder at
402 * the end. (which unmap is needed for ELF images with holes.)
405 total_size = ELF_PAGEALIGN(total_size);
406 map_addr = vm_mmap(filep, addr, total_size, prot, type, off);
407 if (!BAD_ADDR(map_addr))
408 vm_munmap(map_addr+size, total_size-size);
410 map_addr = vm_mmap(filep, addr, size, prot, type, off);
412 if (!BAD_ADDR(map_addr) && tcm_tag != TCM_INVALID_TAG) {
413 struct tcm_allocation *tcm;
414 unsigned long tcm_addr;
416 tcm = kmalloc(sizeof(*tcm), GFP_KERNEL);
420 tcm_addr = tcm_alloc(tcm_tag, raw_size);
421 if (tcm_addr != addr) {
427 tcm->addr = tcm_addr;
428 tcm->size = raw_size;
430 list_add(&tcm->list, ¤t->mm->context.tcm);
432 eppnt->p_vaddr = map_addr;
433 if (copy_from_user((void *) addr, (void __user *) map_addr,