avoid endless loops in lib/swiotlb.c

[wrt350n-kernel.git] / arch / parisc / kernel / processor.c

/*    $Id: processor.c,v 1.1 2002/07/20 16:27:06 rhirst Exp $
 *
 *    Initial setup-routines for HP 9000 based hardware.
 *
 *    Copyright (C) 1991, 1992, 1995  Linus Torvalds
 *    Modifications for PA-RISC (C) 1999 Helge Deller <deller@gmx.de>
 *    Modifications copyright 1999 SuSE GmbH (Philipp Rumpf)
 *    Modifications copyright 2000 Martin K. Petersen <mkp@mkp.net>
 *    Modifications copyright 2000 Philipp Rumpf <prumpf@tux.org>
 *    Modifications copyright 2001 Ryan Bradetich <rbradetich@uswest.net>
 *
 *    Initial PA-RISC Version: 04-23-1999 by Helge Deller
 *
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2, or (at your option)
 *    any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/cpu.h>
#include <asm/param.h>
#include <asm/cache.h>
#include <asm/hardware.h>       /* for register_parisc_driver() stuff */
#include <asm/processor.h>
#include <asm/page.h>
#include <asm/pdc.h>
#include <asm/pdcpat.h>
#include <asm/irq.h>            /* for struct irq_region */
#include <asm/parisc-device.h>

struct system_cpuinfo_parisc boot_cpu_data __read_mostly;
EXPORT_SYMBOL(boot_cpu_data);

struct cpuinfo_parisc cpu_data[NR_CPUS] __read_mostly;

extern int update_cr16_clocksource(void);       /* from time.c */

/*
**      PARISC CPU driver - claim "device" and initialize CPU data structures.
**
** Consolidate per CPU initialization into (mostly) one module.
** Monarch CPU will initialize boot_cpu_data which shouldn't
** change once the system has booted.
**
** The callback *should* do per-instance initialization of
** everything including the monarch. "Per CPU" init code in
** setup.c:start_parisc() has migrated here and start_parisc()
** will call register_parisc_driver(&cpu_driver) before calling do_inventory().
**
** The goal of consolidating CPU initialization into one place is
** to make sure all CPUs get initialized the same way.
** The code path not shared is how PDC hands control of the CPU to the OS.
** The initialization of OS data structures is the same (done below).
*/

/**
 * processor_probe - Determine if processor driver should claim this device.
 * @dev: The device which has been found.
 *
 * Determine if processor driver should claim this chip (return 0) or not 
 * (return 1).  If so, initialize the chip and tell other partners in crime 
 * they have work to do.
 */
static int __cpuinit processor_probe(struct parisc_device *dev)
{
        unsigned long txn_addr;
        unsigned long cpuid;
        struct cpuinfo_parisc *p;

#ifdef CONFIG_SMP
        if (num_online_cpus() >= NR_CPUS) {
                printk(KERN_INFO "num_online_cpus() >= NR_CPUS\n");
                return 1;
        }
#else
        if (boot_cpu_data.cpu_count > 0) {
                printk(KERN_INFO "CONFIG_SMP=n  ignoring additional CPUs\n");
                return 1;
        }
#endif

        /* logical CPU ID and update global counter
         * May get overwritten by PAT code.
         */
        cpuid = boot_cpu_data.cpu_count;
        txn_addr = dev->hpa.start;      /* for legacy PDC */

#ifdef CONFIG_64BIT
        if (is_pdc_pat()) {
                ulong status;
                unsigned long bytecnt;
                pdc_pat_cell_mod_maddr_block_t pa_pdc_cell;
#undef USE_PAT_CPUID
#ifdef USE_PAT_CPUID
                struct pdc_pat_cpu_num cpu_info;
#endif

                status = pdc_pat_cell_module(&bytecnt, dev->pcell_loc,
                        dev->mod_index, PA_VIEW, &pa_pdc_cell);

                BUG_ON(PDC_OK != status);

                /* verify it's the same as what do_pat_inventory() found */
                BUG_ON(dev->mod_info != pa_pdc_cell.mod_info);
                BUG_ON(dev->pmod_loc != pa_pdc_cell.mod_location);

                txn_addr = pa_pdc_cell.mod[0];   /* id_eid for IO sapic */

#ifdef USE_PAT_CPUID
/* We need contiguous numbers for cpuid. Firmware's notion
 * of cpuid is for physical CPUs and we just don't care yet.
 * We'll care when we need to query PAT PDC about a CPU *after*
 * boot time (ie shutdown a CPU from an OS perspective).
 */
                /* get the cpu number */
                status = pdc_pat_cpu_get_number(&cpu_info, dev->hpa.start);

                BUG_ON(PDC_OK != status);

                if (cpu_info.cpu_num >= NR_CPUS) {
                        printk(KERN_WARNING "IGNORING CPU at 0x%x,"
                                " cpu_slot_id > NR_CPUS"
                                " (%ld > %d)\n",
                                dev->hpa.start, cpu_info.cpu_num, NR_CPUS);
                        /* Ignore CPU since it will only crash */
                        boot_cpu_data.cpu_count--;
                        return 1;
                } else {
                        cpuid = cpu_info.cpu_num;
                }
#endif
        }
#endif

        p = &cpu_data[cpuid];
        boot_cpu_data.cpu_count++;

        /* initialize counters - CPU 0 gets it_value set in time_init() */
        if (cpuid)
                memset(p, 0, sizeof(struct cpuinfo_parisc));

        p->loops_per_jiffy = loops_per_jiffy;
        p->dev = dev;           /* Save IODC data in case we need it */
        p->hpa = dev->hpa.start;        /* save CPU hpa */
        p->cpuid = cpuid;       /* save CPU id */
        p->txn_addr = txn_addr; /* save CPU IRQ address */
#ifdef CONFIG_SMP
        /*
        ** FIXME: review if any other initialization is clobbered
        **      for boot_cpu by the above memset().
        */

        /* stolen from init_percpu_prof() */
        cpu_data[cpuid].prof_counter = 1;
        cpu_data[cpuid].prof_multiplier = 1;
#endif

        /*
        ** CONFIG_SMP: init_smp_config() will attempt to get CPUs into
        ** OS control. RENDEZVOUS is the default state - see mem_set above.
        **      p->state = STATE_RENDEZVOUS;
        */

#if 0
        /* CPU 0 IRQ table is statically allocated/initialized */
        if (cpuid) {
                struct irqaction actions[];

                /*
                ** itimer and ipi IRQ handlers are statically initialized in
                ** arch/parisc/kernel/irq.c. ie Don't need to register them.
                */
                actions = kmalloc(sizeof(struct irqaction)*MAX_CPU_IRQ, GFP_ATOMIC);
                if (!actions) {
                        /* not getting it's own table, share with monarch */
                        actions = cpu_irq_actions[0];
                }

                cpu_irq_actions[cpuid] = actions;
        }
#endif

        /* 
         * Bring this CPU up now! (ignore bootstrap cpuid == 0)
         */
#ifdef CONFIG_SMP
        if (cpuid) {
                cpu_set(cpuid, cpu_present_map);
                cpu_up(cpuid);
        }
#endif

        /* If we've registered more than one cpu,
         * we'll use the jiffies clocksource since cr16
         * is not synchronized between CPUs.
         */
        update_cr16_clocksource();

        return 0;
}

/**
 * collect_boot_cpu_data - Fill the boot_cpu_data structure.
 *
 * This function collects and stores the generic processor information
 * in the boot_cpu_data structure.
 */
void __init collect_boot_cpu_data(void)
{
        memset(&boot_cpu_data, 0, sizeof(boot_cpu_data));

        boot_cpu_data.cpu_hz = 100 * PAGE0->mem_10msec; /* Hz of this PARISC */

        /* get CPU-Model Information... */
#define p ((unsigned long *)&boot_cpu_data.pdc.model)
        if (pdc_model_info(&boot_cpu_data.pdc.model) == PDC_OK)
                printk(KERN_INFO 
                        "model %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
                        p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8]);
#undef p

        if (pdc_model_versions(&boot_cpu_data.pdc.versions, 0) == PDC_OK)
                printk(KERN_INFO "vers  %08lx\n", 
                        boot_cpu_data.pdc.versions);

        if (pdc_model_cpuid(&boot_cpu_data.pdc.cpuid) == PDC_OK)
                printk(KERN_INFO "CPUID vers %ld rev %ld (0x%08lx)\n",
                        (boot_cpu_data.pdc.cpuid >> 5) & 127,
                        boot_cpu_data.pdc.cpuid & 31,
                        boot_cpu_data.pdc.cpuid);

        if (pdc_model_capabilities(&boot_cpu_data.pdc.capabilities) == PDC_OK)
                printk(KERN_INFO "capabilities 0x%lx\n",
                        boot_cpu_data.pdc.capabilities);

        if (pdc_model_sysmodel(boot_cpu_data.pdc.sys_model_name) == PDC_OK)
                printk(KERN_INFO "model %s\n",
                        boot_cpu_data.pdc.sys_model_name);

        boot_cpu_data.hversion =  boot_cpu_data.pdc.model.hversion;
        boot_cpu_data.sversion =  boot_cpu_data.pdc.model.sversion;

        boot_cpu_data.cpu_type = parisc_get_cpu_type(boot_cpu_data.hversion);
        boot_cpu_data.cpu_name = cpu_name_version[boot_cpu_data.cpu_type][0];
        boot_cpu_data.family_name = cpu_name_version[boot_cpu_data.cpu_type][1];
}


/**
 * init_cpu_profiler - enable/setup per cpu profiling hooks.
 * @cpunum: The processor instance.
 *
 * FIXME: doesn't do much yet...
 */
static inline void __init
init_percpu_prof(int cpunum)
{
        cpu_data[cpunum].prof_counter = 1;
        cpu_data[cpunum].prof_multiplier = 1;
}


/**
 * init_per_cpu - Handle individual processor initializations.
 * @cpunum: logical processor number.
 *
 * This function handles initialization for *every* CPU
 * in the system:
 *
 * o Set "default" CPU width for trap handlers
 *
 * o Enable FP coprocessor
 *   REVISIT: this could be done in the "code 22" trap handler.
 *      (frowands idea - that way we know which processes need FP
 *      registers saved on the interrupt stack.)
 *   NEWS FLASH: wide kernels need FP coprocessor enabled to handle
 *      formatted printing of %lx for example (double divides I think)
 *
 * o Enable CPU profiling hooks.
 */
int __init init_per_cpu(int cpunum)
{
        int ret;
        struct pdc_coproc_cfg coproc_cfg;

        set_firmware_width();
        ret = pdc_coproc_cfg(&coproc_cfg);

        if(ret >= 0 && coproc_cfg.ccr_functional) {
                mtctl(coproc_cfg.ccr_functional, 10);  /* 10 == Coprocessor Control Reg */

                /* FWIW, FP rev/model is a more accurate way to determine
                ** CPU type. CPU rev/model has some ambiguous cases.
                */
                cpu_data[cpunum].fp_rev = coproc_cfg.revision;
                cpu_data[cpunum].fp_model = coproc_cfg.model;

                printk(KERN_INFO  "FP[%d] enabled: Rev %ld Model %ld\n",
                        cpunum, coproc_cfg.revision, coproc_cfg.model);

                /*
                ** store status register to stack (hopefully aligned)
                ** and clear the T-bit.
                */
                asm volatile ("fstd    %fr0,8(%sp)");

        } else {
                printk(KERN_WARNING  "WARNING: No FP CoProcessor?!"
                        " (coproc_cfg.ccr_functional == 0x%lx, expected 0xc0)\n"
#ifdef CONFIG_64BIT
                        "Halting Machine - FP required\n"
#endif
                        , coproc_cfg.ccr_functional);
#ifdef CONFIG_64BIT
                mdelay(100);    /* previous chars get pushed to console */
                panic("FP CoProc not reported");
#endif
        }

        /* FUTURE: Enable Performance Monitor : ccr bit 0x20 */
        init_percpu_prof(cpunum);

        return ret;
}

/*
 * Display CPU info for all CPUs.
 */
int
show_cpuinfo (struct seq_file *m, void *v)
{
        int     n;

        for(n=0; n<boot_cpu_data.cpu_count; n++) {
#ifdef CONFIG_SMP
                if (0 == cpu_data[n].hpa)
                        continue;
#endif
                seq_printf(m, "processor\t: %d\n"
                                "cpu family\t: PA-RISC %s\n",
                                 n, boot_cpu_data.family_name);

                seq_printf(m, "cpu\t\t: %s\n",  boot_cpu_data.cpu_name );

                /* cpu MHz */
                seq_printf(m, "cpu MHz\t\t: %d.%06d\n",
                                 boot_cpu_data.cpu_hz / 1000000,
                                 boot_cpu_data.cpu_hz % 1000000  );

                seq_printf(m, "model\t\t: %s\n"
                                "model name\t: %s\n",
                                 boot_cpu_data.pdc.sys_model_name,
                                 cpu_data[n].dev ? 
                                 cpu_data[n].dev->name : "Unknown" );

                seq_printf(m, "hversion\t: 0x%08x\n"
                                "sversion\t: 0x%08x\n",
                                 boot_cpu_data.hversion,
                                 boot_cpu_data.sversion );

                /* print cachesize info */
                show_cache_info(m);

                seq_printf(m, "bogomips\t: %lu.%02lu\n",
                             cpu_data[n].loops_per_jiffy / (500000 / HZ),
                             (cpu_data[n].loops_per_jiffy / (5000 / HZ)) % 100);

                seq_printf(m, "software id\t: %ld\n\n",
                                boot_cpu_data.pdc.model.sw_id);
        }
        return 0;
}

static const struct parisc_device_id processor_tbl[] = {
        { HPHW_NPROC, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, SVERSION_ANY_ID },
        { 0, }
};

static struct parisc_driver cpu_driver = {
        .name           = "CPU",
        .id_table       = processor_tbl,
        .probe          = processor_probe
};

/**
 * processor_init - Processor initialization procedure.
 *
 * Register this driver.
 */
void __init processor_init(void)
{
        register_parisc_driver(&cpu_driver);
}