platform_powermac.c

/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2008 Marcel Moolenaar
 * Copyright (c) 2009 Nathan Whitehorn
 * 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 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/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/bus.h>
#include <sys/pcpu.h>
#include <sys/proc.h>
#include <sys/smp.h>
#include <vm/vm.h>
#include <vm/pmap.h>

#include <machine/altivec.h>	/* For save_vec() */
#include <machine/bus.h>
#include <machine/cpu.h>
#include <machine/fpu.h>	/* For save_fpu() */
#include <machine/hid.h>
#include <machine/platformvar.h>
#include <machine/setjmp.h>
#include <machine/smp.h>
#include <machine/spr.h>

#include <dev/ofw/openfirm.h>
#include <machine/ofw_machdep.h>

#include <powerpc/powermac/platform_powermac.h>

#include "platform_if.h"

extern volatile void *ap_pcpu;

static void dummy_timebase(device_t, bool);
static device_t powermac_tb_dev;
static void (*freeze_timebase)(device_t, bool) = dummy_timebase;

static int powermac_probe(platform_t);
static int powermac_attach(platform_t);
void powermac_mem_regions(platform_t, struct mem_region *phys, int *physsz,
    struct mem_region *avail, int *availsz);
static u_long powermac_timebase_freq(platform_t, struct cpuref *cpuref);
static int powermac_smp_first_cpu(platform_t, struct cpuref *cpuref);
static int powermac_smp_next_cpu(platform_t, struct cpuref *cpuref);
static int powermac_smp_get_bsp(platform_t, struct cpuref *cpuref);
static int powermac_smp_start_cpu(platform_t, struct pcpu *cpu);
static void powermac_smp_timebase_sync(platform_t, u_long tb, int ap);
static void powermac_reset(platform_t);
#ifndef __powerpc64__
static void powermac_sleep(platform_t);
#endif

static platform_method_t powermac_methods[] = {
	PLATFORMMETHOD(platform_probe, 		powermac_probe),
	PLATFORMMETHOD(platform_attach,		powermac_attach),
	PLATFORMMETHOD(platform_mem_regions,	powermac_mem_regions),
	PLATFORMMETHOD(platform_timebase_freq,	powermac_timebase_freq),

	PLATFORMMETHOD(platform_smp_first_cpu,	powermac_smp_first_cpu),
	PLATFORMMETHOD(platform_smp_next_cpu,	powermac_smp_next_cpu),
	PLATFORMMETHOD(platform_smp_get_bsp,	powermac_smp_get_bsp),
	PLATFORMMETHOD(platform_smp_start_cpu,	powermac_smp_start_cpu),
	PLATFORMMETHOD(platform_smp_timebase_sync, powermac_smp_timebase_sync),

	PLATFORMMETHOD(platform_reset,		powermac_reset),
#ifndef __powerpc64__
	PLATFORMMETHOD(platform_sleep,		powermac_sleep),
#endif

	PLATFORMMETHOD_END
};

static platform_def_t powermac_platform = {
	"powermac",
	powermac_methods,
	0
};

PLATFORM_DEF(powermac_platform);

static int
powermac_probe(platform_t plat)
{
	char compat[255];
	ssize_t compatlen;
	char *curstr;
	phandle_t root;

	root = OF_peer(0);
	if (root == 0)
		return (ENXIO);

	compatlen = OF_getprop(root, "compatible", compat, sizeof(compat));

	for (curstr = compat; curstr < compat + compatlen;
	    curstr += strlen(curstr) + 1) {
		if (strncmp(curstr, "MacRISC", 7) == 0)
			return (BUS_PROBE_SPECIFIC);
	}

	return (ENXIO);
}

void
powermac_mem_regions(platform_t plat, struct mem_region *phys, int *physsz,
    struct mem_region *avail, int *availsz)
{
	phandle_t memory;
	cell_t memoryprop[PHYS_AVAIL_SZ * 2];
	ssize_t propsize, i, j;
	int physacells = 1;

	memory = OF_finddevice("/memory");
	if (memory == -1)
		memory = OF_finddevice("/memory@0");

	/* "reg" has variable #address-cells, but #size-cells is always 1 */
	OF_getprop(OF_parent(memory), "#address-cells", &physacells,
	    sizeof(physacells));

	propsize = OF_getprop(memory, "reg", memoryprop, sizeof(memoryprop));
	propsize /= sizeof(cell_t);
	for (i = 0, j = 0; i < propsize; i += physacells+1, j++) {
		phys[j].mr_start = memoryprop[i];
		if (physacells == 2) {
#ifndef __powerpc64__
			/* On 32-bit PPC, ignore regions starting above 4 GB */
			if (memoryprop[i] != 0) {
				j--;
				continue;
			}
#else
			phys[j].mr_start <<= 32;
#endif
			phys[j].mr_start |= memoryprop[i+1];
		}
		phys[j].mr_size = memoryprop[i + physacells];
	}
	*physsz = j;

	/* "available" always has #address-cells = 1 */
	propsize = OF_getprop(memory, "available", memoryprop,
	    sizeof(memoryprop));
	if (propsize <= 0) {
		for (i = 0; i < *physsz; i++) {
			avail[i].mr_start = phys[i].mr_start;
			avail[i].mr_size = phys[i].mr_size;
		}

		*availsz = *physsz;
	} else {
		propsize /= sizeof(cell_t);
		for (i = 0, j = 0; i < propsize; i += 2, j++) {
			avail[j].mr_start = memoryprop[i];
			avail[j].mr_size = memoryprop[i + 1];
		}

#ifdef __powerpc64__
		/* Add in regions above 4 GB to the available list */
		for (i = 0; i < *physsz; i++) {
			if (phys[i].mr_start > BUS_SPACE_MAXADDR_32BIT) {
				avail[j].mr_start = phys[i].mr_start;
				avail[j].mr_size = phys[i].mr_size;
				j++;
			}
		}
#endif
		*availsz = j;
	}
}

static int
powermac_attach(platform_t plat)
{
	phandle_t rootnode;
	char model[32];

	/*
	 * Quiesce Open Firmware on PowerMac11,2 and 12,1. It is
	 * necessary there to shut down a background thread doing fan
	 * management, and is harmful on other machines (it will make OF
	 * shut off power to various system components it had turned on).
	 *
	 * Note: we don't need to worry about which OF module we are
	 * using since this is called only from very early boot, within
	 * OF's boot context.
	 */

	rootnode = OF_finddevice("/");
	if (OF_getprop(rootnode, "model", model, sizeof(model)) > 0) {
		if (strcmp(model, "PowerMac11,2") == 0 ||
		    strcmp(model, "PowerMac12,1") == 0) {
			ofw_quiesce();
		}
	}

	return (0);
}

static u_long
powermac_timebase_freq(platform_t plat, struct cpuref *cpuref)
{
	phandle_t phandle;
	int32_t ticks = -1;

	phandle = cpuref->cr_hwref;

	OF_getprop(phandle, "timebase-frequency", &ticks, sizeof(ticks));

	if (ticks <= 0)
		panic("Unable to determine timebase frequency!");

	return (ticks);
}

static int
powermac_smp_fill_cpuref(struct cpuref *cpuref, phandle_t cpu)
{
	cell_t cpuid;
	int res;

	cpuref->cr_hwref = cpu;
	res = OF_getprop(cpu, "reg", &cpuid, sizeof(cpuid));

	/*
	 * psim doesn't have a reg property, so assume 0 as for the
	 * uniprocessor case in the CHRP spec. 
	 */
	if (res < 0) {
		cpuid = 0;
	}

	cpuref->cr_cpuid = cpuid & 0xff;
	return (0);
}

static int
powermac_smp_first_cpu(platform_t plat, struct cpuref *cpuref)
{
	char buf[8];
	phandle_t cpu, dev, root;
	int res;

	root = OF_peer(0);

	dev = OF_child(root);
	while (dev != 0) {
		res = OF_getprop(dev, "name", buf, sizeof(buf));
		if (res > 0 && strcmp(buf, "cpus") == 0)
			break;
		dev = OF_peer(dev);
	}
	if (dev == 0) {
		/*
		 * psim doesn't have a name property on the /cpus node,
		 * but it can be found directly
		 */
		dev = OF_finddevice("/cpus");
		if (dev == -1)
			return (ENOENT);
	}

	cpu = OF_child(dev);

	while (cpu != 0) {
		res = OF_getprop(cpu, "device_type", buf, sizeof(buf));
		if (res > 0 && strcmp(buf, "cpu") == 0)
			break;
		cpu = OF_peer(cpu);
	}
	if (cpu == 0)
		return (ENOENT);

	return (powermac_smp_fill_cpuref(cpuref, cpu));
}

static int
powermac_smp_next_cpu(platform_t plat, struct cpuref *cpuref)
{
	char buf[8];
	phandle_t cpu;
	int res;

	cpu = OF_peer(cpuref->cr_hwref);
	while (cpu != 0) {
		res = OF_getprop(cpu, "device_type", buf, sizeof(buf));
		if (res > 0 && strcmp(buf, "cpu") == 0)
			break;
		cpu = OF_peer(cpu);
	}
	if (cpu == 0)
		return (ENOENT);

	return (powermac_smp_fill_cpuref(cpuref, cpu));
}

static int
powermac_smp_get_bsp(platform_t plat, struct cpuref *cpuref)
{
	ihandle_t inst;
	phandle_t bsp, chosen;
	int res;

	chosen = OF_finddevice("/chosen");
	if (chosen == -1)
		return (ENXIO);

	res = OF_getprop(chosen, "cpu", &inst, sizeof(inst));
	if (res < 0)
		return (ENXIO);

	bsp = OF_instance_to_package(inst);
	return (powermac_smp_fill_cpuref(cpuref, bsp));
}

static int
powermac_smp_start_cpu(platform_t plat, struct pcpu *pc)
{
#ifdef SMP
	phandle_t cpu;
	volatile uint8_t *rstvec;
	static volatile uint8_t *rstvec_virtbase = NULL;
	int res, reset, timeout;

	cpu = pc->pc_hwref;
	res = OF_getprop(cpu, "soft-reset", &reset, sizeof(reset));
	if (res < 0) {
		reset = 0x58;

		switch (pc->pc_cpuid) {
		case 0:
			reset += 0x03;
			break;
		case 1:
			reset += 0x04;
			break;
		case 2:
			reset += 0x0f;
			break;
		case 3:
			reset += 0x10;
			break;
		default:
			return (ENXIO);
		}
	}

	ap_pcpu = pc;

	if (rstvec_virtbase == NULL)
		rstvec_virtbase = pmap_mapdev(0x80000000, PAGE_SIZE);

	rstvec = rstvec_virtbase + reset;

	*rstvec = 4;
	powerpc_sync();
	(void)(*rstvec);
	powerpc_sync();
	DELAY(1);
	*rstvec = 0;
	powerpc_sync();
	(void)(*rstvec);
	powerpc_sync();

	timeout = 10000;
	while (!pc->pc_awake && timeout--)
		DELAY(100);

	return ((pc->pc_awake) ? 0 : EBUSY);
#else
	/* No SMP support */
	return (ENXIO);
#endif
}

void
powermac_register_timebase(device_t dev, powermac_tb_disable_t cb)
{
	powermac_tb_dev = dev;
	freeze_timebase = cb;
}

static void
powermac_smp_timebase_sync(platform_t plat, u_long tb, int ap)
{
	static volatile bool tb_ready;
	static volatile int cpu_done;

	/*
	 * XXX Temporary fallback for platforms we don't know how to freeze.
	 *
	 * This needs to be replaced with a cpu-to-cpu software sync
	 * protocol, because this is not a consistent way to sync timebase.
	 */
	mttb(tb);
	if (freeze_timebase == dummy_timebase)
		return;

	if (ap) {
		/* APs.  Hold off until we get a stable timebase. */
		critical_enter();
		while (!tb_ready)
			atomic_thread_fence_seq_cst();
		mttb(tb);
		atomic_add_int(&cpu_done, 1);
		while (cpu_done < mp_ncpus)
			atomic_thread_fence_seq_cst();
		critical_exit();
	} else {
		/* BSP */
		critical_enter();
		/* Ensure cpu_done is zeroed so we can resync at runtime */
		atomic_set_int(&cpu_done, 0);
		freeze_timebase(powermac_tb_dev, true);
		tb_ready = true;
		mttb(tb);
		atomic_add_int(&cpu_done, 1);
		while (cpu_done < mp_ncpus)
			atomic_thread_fence_seq_cst();
		freeze_timebase(powermac_tb_dev, false);
		/* Reset tb_ready so we can resync at runtime */
		tb_ready = false;
		critical_exit();
	}
}

/* Fallback freeze. In case no real handler is found in the device tree. */
static void
dummy_timebase(device_t dev, bool freeze)
{
	/* Nothing to do here, move along. */
}

static void
powermac_reset(platform_t platform)
{
	OF_reboot();
}

#ifndef __powerpc64__
void
powermac_sleep(platform_t platform)
{
	/* Only supports MPC745x for now. */
	if (!MPC745X_P(mfspr(SPR_PVR) >> 16)) {
		printf("sleep only supported for G4 PowerMac hardware.\n");
		return;
	}

	*(unsigned long *)0x80 = 0x100;
	mpc745x_sleep();
}
#endif