/*	$NetBSD: hppa_machdep.c,v 1.29.34.1 2022/05/14 11:32:43 martin Exp $	*/

/*-
 * Copyright (c) 1997 The NetBSD Foundation, Inc.
 * 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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``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 FOUNDATION OR CONTRIBUTORS
 * 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 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/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: hppa_machdep.c,v 1.29.34.1 2022/05/14 11:32:43 martin Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/lwp.h>
#include <sys/proc.h>
#include <sys/ras.h>
#include <sys/cpu.h>

#include <sys/kernel.h>

#include <uvm/uvm_extern.h>

#include <machine/cpufunc.h>
#include <machine/pcb.h>
#include <machine/mcontext.h>
#include <hppa/hppa/machdep.h>

/* the following is used externally (sysctl_hw) */
char	machine_arch[] = MACHINE_ARCH;	/* from <machine/param.h> */

/*
 * XXX fredette - much of the TLB trap handler setup should
 * probably be moved here from hppa/hppa/machdep.c, seeing
 * that there's related code already in hppa/hppa/trap.S.
 */

void
cpu_getmcontext(struct lwp *l, mcontext_t *mcp, unsigned int *flags)
{
	struct trapframe *tf = l->l_md.md_regs;
	struct pcb *pcb = lwp_getpcb(l);
	__greg_t *gr = mcp->__gregs;
	__greg_t ras_pc;

	gr[0]  = tf->tf_ipsw;
	gr[1]  = tf->tf_r1;
	gr[2]  = tf->tf_rp;
	gr[3]  = tf->tf_r3;
	gr[4]  = tf->tf_r4;
	gr[5]  = tf->tf_r5;
	gr[6]  = tf->tf_r6;
	gr[7]  = tf->tf_r7;
	gr[8]  = tf->tf_r8;
	gr[9]  = tf->tf_r9;
	gr[10] = tf->tf_r10;
	gr[11] = tf->tf_r11;
	gr[12] = tf->tf_r12;
	gr[13] = tf->tf_r13;
	gr[14] = tf->tf_r14;
	gr[15] = tf->tf_r15;
	gr[16] = tf->tf_r16;
	gr[17] = tf->tf_r17;
	gr[18] = tf->tf_r18;
	gr[19] = tf->tf_t4;
	gr[20] = tf->tf_t3;
	gr[21] = tf->tf_t2;
	gr[22] = tf->tf_t1;
	gr[23] = tf->tf_arg3;
	gr[24] = tf->tf_arg2;
	gr[25] = tf->tf_arg1;
	gr[26] = tf->tf_arg0;
	gr[27] = tf->tf_dp;
	gr[28] = tf->tf_ret0;
	gr[29] = tf->tf_ret1;
	gr[30] = tf->tf_sp;
	gr[31] = tf->tf_r31;

	gr[_REG_SAR] = tf->tf_sar;
	gr[_REG_PCSQH] = tf->tf_iisq_head;
	gr[_REG_PCSQT] = tf->tf_iisq_tail;
	gr[_REG_PCOQH] = tf->tf_iioq_head;
	gr[_REG_PCOQT] = tf->tf_iioq_tail;
	gr[_REG_SR0] = tf->tf_sr0;
	gr[_REG_SR1] = tf->tf_sr1;
	gr[_REG_SR2] = tf->tf_sr2;
	gr[_REG_SR3] = tf->tf_sr3;
	gr[_REG_SR4] = tf->tf_sr4;
	gr[_REG_CR27] = tf->tf_cr27;
#if 0
	gr[_REG_CR26] = tf->tf_cr26;
#endif

	ras_pc = (__greg_t)ras_lookup(l->l_proc,
	    (void *)(gr[_REG_PCOQH] & ~HPPA_PC_PRIV_MASK));
	if (ras_pc != -1) {
		ras_pc |= HPPA_PC_PRIV_USER;
		gr[_REG_PCOQH] = ras_pc;
		gr[_REG_PCOQT] = ras_pc + 4;
	}

	*flags |= _UC_CPU | _UC_TLSBASE;

	if (l->l_md.md_flags & 0) {
		return;
	}

	hppa_fpu_flush(l);
	memcpy(&mcp->__fpregs, pcb->pcb_fpregs, sizeof(mcp->__fpregs));
	*flags |= _UC_FPU;
}

int
cpu_mcontext_validate(struct lwp *l, const mcontext_t *mcp)
{
	const __greg_t *gr = mcp->__gregs;

	if ((gr[_REG_PSW] & (PSW_MBS|PSW_MBZ)) != PSW_MBS) {
		return EINVAL;
	}

#if 0
	/*
	 * XXX
	 * Force the space regs and priviledge bits to
	 * the right values in the trapframe for now.
	 */

	if (gr[_REG_PCSQH] != pmap_sid(pmap, gr[_REG_PCOQH])) {
		return EINVAL;
	}

	if (gr[_REG_PCSQT] != pmap_sid(pmap, gr[_REG_PCOQT])) {
		return EINVAL;
	}

	if (gr[_REG_PCOQH] < 0xc0000020 &&
	    (gr[_REG_PCOQH] & HPPA_PC_PRIV_MASK) != HPPA_PC_PRIV_USER) {
		return EINVAL;
	}

	if (gr[_REG_PCOQT] < 0xc0000020 &&
	    (gr[_REG_PCOQT] & HPPA_PC_PRIV_MASK) != HPPA_PC_PRIV_USER) {
		return EINVAL;
	}
#endif

	return 0;
}

int
cpu_setmcontext(struct lwp *l, const mcontext_t *mcp, unsigned int flags)
{
	struct trapframe *tf = l->l_md.md_regs;
	struct proc *p = l->l_proc;
	struct pmap *pmap = p->p_vmspace->vm_map.pmap;
	const __greg_t *gr = mcp->__gregs;
	int error;

	if ((flags & _UC_CPU) != 0) {
		error = cpu_mcontext_validate(l, mcp);
		if (error)
			return error;

		tf->tf_ipsw	= gr[0] |
		    (hppa_cpu_ispa20_p() ? PSW_O : 0);
		tf->tf_r1	= gr[1];
		tf->tf_rp	= gr[2];
		tf->tf_r3	= gr[3];
		tf->tf_r4	= gr[4];
		tf->tf_r5	= gr[5];
		tf->tf_r6	= gr[6];
		tf->tf_r7	= gr[7];
		tf->tf_r8	= gr[8];
		tf->tf_r9	= gr[9];
		tf->tf_r10	= gr[10];
		tf->tf_r11	= gr[11];
		tf->tf_r12	= gr[12];
		tf->tf_r13	= gr[13];
		tf->tf_r14	= gr[14];
		tf->tf_r15	= gr[15];
		tf->tf_r16	= gr[16];
		tf->tf_r17	= gr[17];
		tf->tf_r18	= gr[18];
		tf->tf_t4	= gr[19];
		tf->tf_t3	= gr[20];
		tf->tf_t2	= gr[21];
		tf->tf_t1	= gr[22];
		tf->tf_arg3	= gr[23];
		tf->tf_arg2	= gr[24];
		tf->tf_arg1	= gr[25];
		tf->tf_arg0	= gr[26];
		tf->tf_dp	= gr[27];
		tf->tf_ret0	= gr[28];
		tf->tf_ret1	= gr[29];
		tf->tf_sp	= gr[30];
		tf->tf_r31	= gr[31];
		tf->tf_sar	= gr[_REG_SAR];
		tf->tf_iisq_head = pmap_sid(pmap, gr[_REG_PCOQH]);
		tf->tf_iisq_tail = pmap_sid(pmap, gr[_REG_PCOQT]);

		tf->tf_iioq_head = gr[_REG_PCOQH];
		tf->tf_iioq_tail = gr[_REG_PCOQT];

		if (tf->tf_iioq_head >= 0xc0000020) {
			tf->tf_iioq_head &= ~HPPA_PC_PRIV_MASK;
		} else {
			tf->tf_iioq_head |= HPPA_PC_PRIV_USER;
		}
		if (tf->tf_iioq_tail >= 0xc0000020) {
			tf->tf_iioq_tail &= ~HPPA_PC_PRIV_MASK;
		} else {
			tf->tf_iioq_tail |= HPPA_PC_PRIV_USER;
		}

#if 0
		tf->tf_sr0	= gr[_REG_SR0];
		tf->tf_sr1	= gr[_REG_SR1];
		tf->tf_sr2	= gr[_REG_SR2];
		tf->tf_sr3	= gr[_REG_SR3];
		tf->tf_sr4	= gr[_REG_SR4];
		tf->tf_cr26	= gr[_REG_CR26];
#endif
	}

	/* Restore the private thread context */
	if (flags & _UC_TLSBASE) {
		lwp_setprivate(l, (void *)(uintptr_t)gr[_REG_CR27]);
		tf->tf_cr27	= gr[_REG_CR27];
	}

	/* Restore the floating point registers */
	if ((flags & _UC_FPU) != 0) {
		struct pcb *pcb = lwp_getpcb(l);

		hppa_fpu_flush(l);
		memcpy(pcb->pcb_fpregs, &mcp->__fpregs, sizeof(mcp->__fpregs));
	}

	mutex_enter(p->p_lock);
	if (flags & _UC_SETSTACK)
		l->l_sigstk.ss_flags |= SS_ONSTACK;
	if (flags & _UC_CLRSTACK)
		l->l_sigstk.ss_flags &= ~SS_ONSTACK;
	mutex_exit(p->p_lock);

	return 0;
}

/*
 * Do RAS processing.
 */

void
hppa_ras(struct lwp *l)
{
	struct proc *p;
	struct trapframe *tf;
	intptr_t rasaddr;

	p = l->l_proc;
	tf = l->l_md.md_regs;

	rasaddr = (intptr_t)ras_lookup(p,
	    (void *)(tf->tf_iioq_head & ~HPPA_PC_PRIV_MASK));
	if (rasaddr != -1) {
		rasaddr |= HPPA_PC_PRIV_USER;
		tf->tf_iioq_head = rasaddr;
		tf->tf_iioq_tail = rasaddr + 4;
	}
}

/*
 * Preempt the current LWP if in interrupt from user mode,
 * or after the current trap/syscall if in system mode.
 */
void
cpu_need_resched(struct cpu_info *ci, int flags)
{
	bool immed = (flags & RESCHED_IMMED) != 0;

	if (ci->ci_want_resched && !immed)
		return;
	ci->ci_want_resched = 1;
	setsoftast(ci->ci_data.cpu_onproc);

#ifdef MULTIPROCESSOR
	if (ci->ci_curlwp != ci->ci_data.cpu_idlelwp) {
		if (immed && ci != curcpu()) {
			/* XXX send IPI */
		}
	}
#endif
}