/*	$OpenBSD: vm_machdep.c,v 1.85 2022/10/25 15:15:38 guenther Exp $	*/

/*
 * Copyright (c) 1999-2004 Michael Shalayeff
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR OR HIS RELATIVES BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF MIND, USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */


#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/signalvar.h>
#include <sys/malloc.h>
#include <sys/buf.h>
#include <sys/vnode.h>
#include <sys/user.h>
#include <sys/ptrace.h>
#include <sys/exec.h>
#include <sys/pool.h>

#include <uvm/uvm_extern.h>

#include <machine/cpufunc.h>
#include <machine/fpu.h>
#include <machine/pmap.h>
#include <machine/pcb.h>

extern struct pool hppa_fppl;

void
cpu_fork(struct proc *p1, struct proc *p2, void *stack, void *tcb,
    void (*func)(void *), void *arg)
{
	struct pcb *pcbp;
	struct trapframe *tf;
	register_t sp;

#ifdef DIAGNOSTIC
	if (round_page(sizeof(struct user)) > NBPG)
		panic("USPACE too small for user");
#endif
	fpu_proc_save(p1);

	pcbp = &p2->p_addr->u_pcb;
	bcopy(&p1->p_addr->u_pcb, pcbp, sizeof(*pcbp));
	/* space is cached for the copy{in,out}'s pleasure */
	pcbp->pcb_space = p2->p_vmspace->vm_map.pmap->pm_space;
	pcbp->pcb_fpstate = pool_get(&hppa_fppl, PR_WAITOK);
	*pcbp->pcb_fpstate = *p1->p_addr->u_pcb.pcb_fpstate;
	/* reset any of the pending FPU exceptions from parent */
	pcbp->pcb_fpstate->hfp_regs.fpr_regs[0] =
	    HPPA_FPU_FORK(pcbp->pcb_fpstate->hfp_regs.fpr_regs[0]);
	pcbp->pcb_fpstate->hfp_regs.fpr_regs[1] = 0;
	pcbp->pcb_fpstate->hfp_regs.fpr_regs[2] = 0;
	pcbp->pcb_fpstate->hfp_regs.fpr_regs[3] = 0;

	p2->p_md.md_bpva = p1->p_md.md_bpva;
	p2->p_md.md_bpsave[0] = p1->p_md.md_bpsave[0];
	p2->p_md.md_bpsave[1] = p1->p_md.md_bpsave[1];

	sp = (register_t)p2->p_addr + NBPG;
	p2->p_md.md_regs = tf = (struct trapframe *)sp;
	sp += sizeof(struct trapframe);
	bcopy(p1->p_md.md_regs, tf, sizeof(*tf));

	tf->tf_cr30 = (paddr_t)pcbp->pcb_fpstate;

	tf->tf_sr0 = tf->tf_sr1 = tf->tf_sr2 = tf->tf_sr3 =
	tf->tf_sr4 = tf->tf_sr5 = tf->tf_sr6 =
	tf->tf_iisq_head = tf->tf_iisq_tail =
		p2->p_vmspace->vm_map.pmap->pm_space;
	tf->tf_pidr1 = tf->tf_pidr2 = pmap_sid2pid(tf->tf_sr0);

	/*
	 * theoretically these could be inherited from the father,
	 * but just in case.
	 */
	tf->tf_sr7 = HPPA_SID_KERNEL;
	mfctl(CR_EIEM, tf->tf_eiem);
	tf->tf_ipsw = PSL_C | PSL_Q | PSL_P | PSL_D | PSL_I /* | PSL_L */ |
	    (curcpu()->ci_psw & PSL_O);

	/*
	 * If specified, give the child a different stack and/or TCB
	 */
	if (stack != NULL)
		setstack(tf, (u_long)stack, 0);	/* XXX ignore error? */
	if (tcb != NULL)
		tf->tf_cr27 = (u_long)tcb;

	/*
	 * Build stack frames for the cpu_switchto & co.
	 */
	sp += HPPA_FRAME_SIZE;
	*(register_t*)(sp - HPPA_FRAME_SIZE) = 0;
	*(register_t*)(sp + HPPA_FRAME_CRP) = (register_t)&proc_trampoline;
	*(register_t*)(sp) = (sp - HPPA_FRAME_SIZE);

	sp += HPPA_FRAME_SIZE + 16*4; /* frame + callee-saved registers */
	*HPPA_FRAME_CARG(0, sp) = (register_t)arg;
	*HPPA_FRAME_CARG(1, sp) = KERNMODE(func);
	pcbp->pcb_ksp = sp;
}

void
cpu_exit(struct proc *p)
{
	struct pcb *pcb = &p->p_addr->u_pcb;

	fpu_proc_flush(p);

	pool_put(&hppa_fppl, pcb->pcb_fpstate);

	pmap_deactivate(p);
	sched_exit(p);
}

struct kmem_va_mode kv_physwait = {
	.kv_map = &phys_map,
	.kv_wait = 1,
};

/*
 * Map an IO request into kernel virtual address space.
 */
void
vmapbuf(struct buf *bp, vsize_t len)
{
	struct kmem_dyn_mode kd_prefer = { .kd_waitok = 1 };
	struct pmap *pm = vm_map_pmap(&bp->b_proc->p_vmspace->vm_map);
	vaddr_t kva, uva;
	vsize_t size, off;

#ifdef DIAGNOSTIC
	if ((bp->b_flags & B_PHYS) == 0)
		panic("vmapbuf");
#endif
	bp->b_saveaddr = bp->b_data;
	uva = trunc_page((vaddr_t)bp->b_data);
	off = (vaddr_t)bp->b_data - uva;
	size = round_page(off + len);

	kd_prefer.kd_prefer = uva;
	kva = (vaddr_t)km_alloc(size, &kv_physwait, &kp_none, &kd_prefer);
	bp->b_data = (caddr_t)(kva + off);
	while (size > 0) {
		paddr_t pa;

		if (pmap_extract(pm, uva, &pa) == FALSE)
			panic("vmapbuf: null page frame");
		else
			pmap_kenter_pa(kva, pa, PROT_READ | PROT_WRITE);
		uva += PAGE_SIZE;
		kva += PAGE_SIZE;
		size -= PAGE_SIZE;
	}
	pmap_update(pmap_kernel());
}

/*
 * Unmap IO request from the kernel virtual address space.
 */
void
vunmapbuf(struct buf *bp, vsize_t len)
{
	vaddr_t addr, off;

#ifdef DIAGNOSTIC
	if ((bp->b_flags & B_PHYS) == 0)
		panic("vunmapbuf");
#endif
	addr = trunc_page((vaddr_t)bp->b_data);
	off = (vaddr_t)bp->b_data - addr;
	len = round_page(off + len);
	pmap_kremove(addr, len);
	pmap_update(pmap_kernel());
	km_free((void *)addr, len, &kv_physwait, &kp_none);
	bp->b_data = bp->b_saveaddr;
	bp->b_saveaddr = NULL;
}