processor.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *    Initial setup-routines for HP 9000 based hardware.
 *
 *    Copyright (C) 1991, 1992, 1995  Linus Torvalds
 *    Modifications for PA-RISC (C) 1999-2008 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
 */
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/random.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 __ro_after_init;
EXPORT_SYMBOL(boot_cpu_data);
#ifdef CONFIG_PA8X00
int _parisc_requires_coherency __ro_after_init;
EXPORT_SYMBOL(_parisc_requires_coherency);
#endif

DEFINE_PER_CPU(struct cpuinfo_parisc, cpu_data);

/*
**  	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).
*/

/**
 * init_cpu_profiler - enable/setup per cpu profiling hooks.
 * @cpunum: The processor instance.
 *
 * FIXME: doesn't do much yet...
 */
static void
init_percpu_prof(unsigned long cpunum)
{
}


/**
 * 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 __init processor_probe(struct parisc_device *dev)
{
	unsigned long txn_addr;
	unsigned long cpuid;
	struct cpuinfo_parisc *p;
	struct pdc_pat_cpu_num cpu_info = { };

#ifdef CONFIG_SMP
	if (num_online_cpus() >= nr_cpu_ids) {
		printk(KERN_INFO "num_online_cpus() >= nr_cpu_ids\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 */
	cpu_info.cpu_num = cpu_info.cpu_loc = cpuid;

#ifdef CONFIG_64BIT
	if (is_pdc_pat()) {
		ulong status;
		unsigned long bytecnt;
	        pdc_pat_cell_mod_maddr_block_t *pa_pdc_cell;

		pa_pdc_cell = kmalloc(sizeof (*pa_pdc_cell), GFP_KERNEL);
		if (!pa_pdc_cell)
			panic("couldn't allocate memory for PDC_PAT_CELL!");

		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 */

		kfree(pa_pdc_cell);

		/* get the cpu number */
		status = pdc_pat_cpu_get_number(&cpu_info, dev->hpa.start);
		BUG_ON(PDC_OK != status);

		pr_info("Logical CPU #%lu is physical cpu #%lu at location "
			"0x%lx with hpa %pa\n",
			cpuid, cpu_info.cpu_num, cpu_info.cpu_loc,
			&dev->hpa.start);

#undef USE_PAT_CPUID
#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).
 */
		if (cpu_info.cpu_num >= NR_CPUS) {
			printk(KERN_WARNING "IGNORING CPU at %pa,"
				" 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 = &per_cpu(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->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 */
	p->cpu_num = cpu_info.cpu_num;
	p->cpu_loc = cpu_info.cpu_loc;

	store_cpu_topology(cpuid);

#ifdef CONFIG_SMP
	/*
	** FIXME: review if any other initialization is clobbered
	**	  for boot_cpu by the above memset().
	*/
	init_percpu_prof(cpuid);
#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) {
		set_cpu_present(cpuid, true);
		add_cpu(cpuid);
	}
#endif

	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)
{
	unsigned long cr16_seed;
	char orig_prod_num[64], current_prod_num[64], serial_no[64];

	memset(&boot_cpu_data, 0, sizeof(boot_cpu_data));

	cr16_seed = get_cycles();
	add_device_randomness(&cr16_seed, sizeof(cr16_seed));

	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]);

		add_device_randomness(&boot_cpu_data.pdc.model,
			sizeof(boot_cpu_data.pdc.model));
	}
#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);

		add_device_randomness(&boot_cpu_data.pdc.versions,
			sizeof(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);

		add_device_randomness(&boot_cpu_data.pdc.cpuid,
			sizeof(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);

	dump_stack_set_arch_desc("%s", 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];

#ifdef CONFIG_PA8X00
	_parisc_requires_coherency = (boot_cpu_data.cpu_type == mako) ||
				(boot_cpu_data.cpu_type == mako2);
#endif

	if (pdc_model_platform_info(orig_prod_num, current_prod_num, serial_no) == PDC_OK) {
		printk(KERN_INFO "product %s, original product %s, S/N: %s\n",
			current_prod_num[0] ? current_prod_num : "n/a",
			orig_prod_num, serial_no);
		add_device_randomness(orig_prod_num, strlen(orig_prod_num));
		add_device_randomness(current_prod_num, strlen(current_prod_num));
		add_device_randomness(serial_no, strlen(serial_no));
	}
}


/**
 * 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);

	store_cpu_topology(cpunum);

	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.
		*/
		per_cpu(cpu_data, cpunum).fp_rev = coproc_cfg.revision;
		per_cpu(cpu_data, cpunum).fp_model = coproc_cfg.model;

		if (cpunum == 0)
			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)
{
	unsigned long cpu;
	char cpu_name[60], *p;

	/* strip PA path from CPU name to not confuse lscpu */
	strlcpy(cpu_name, per_cpu(cpu_data, 0).dev->name, sizeof(cpu_name));
	p = strrchr(cpu_name, '[');
	if (p)
		*(--p) = 0;

	for_each_online_cpu(cpu) {
#ifdef CONFIG_SMP
		const struct cpuinfo_parisc *cpuinfo = &per_cpu(cpu_data, cpu);

		if (0 == cpuinfo->hpa)
			continue;
#endif
		seq_printf(m, "processor\t: %lu\n"
				"cpu family\t: PA-RISC %s\n",
				 cpu, 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  );

#ifdef CONFIG_PARISC_CPU_TOPOLOGY
		seq_printf(m, "physical id\t: %d\n",
				topology_physical_package_id(cpu));
		seq_printf(m, "siblings\t: %d\n",
				cpumask_weight(topology_core_cpumask(cpu)));
		seq_printf(m, "core id\t\t: %d\n", topology_core_id(cpu));
#endif

		seq_printf(m, "capabilities\t:");
		if (boot_cpu_data.pdc.capabilities & PDC_MODEL_OS32)
			seq_puts(m, " os32");
		if (boot_cpu_data.pdc.capabilities & PDC_MODEL_OS64)
			seq_puts(m, " os64");
		if (boot_cpu_data.pdc.capabilities & PDC_MODEL_IOPDIR_FDC)
			seq_puts(m, " iopdir_fdc");
		switch (boot_cpu_data.pdc.capabilities & PDC_MODEL_NVA_MASK) {
		case PDC_MODEL_NVA_SUPPORTED:
			seq_puts(m, " nva_supported");
			break;
		case PDC_MODEL_NVA_SLOW:
			seq_puts(m, " nva_slow");
			break;
		case PDC_MODEL_NVA_UNSUPPORTED:
			seq_puts(m, " needs_equivalent_aliasing");
			break;
		}
		seq_printf(m, " (0x%02lx)\n", boot_cpu_data.pdc.capabilities);

		seq_printf(m, "model\t\t: %s - %s\n",
				 boot_cpu_data.pdc.sys_model_name,
				 cpu_name);

		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",
			     loops_per_jiffy / (500000 / HZ),
			     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[] __initconst = {
	{ HPHW_NPROC, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, SVERSION_ANY_ID },
	{ 0, }
};

static struct parisc_driver cpu_driver __refdata = {
	.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);
}