// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * inventory.c
 *
 * Copyright (c) 1999 The Puffin Group (David Kennedy and Alex deVries)
 * Copyright (c) 2001 Matthew Wilcox for Hewlett-Packard
 *
 * These are the routines to discover what hardware exists in this box.
 * This task is complicated by there being 3 different ways of
 * performing an inventory, depending largely on the age of the box.
 * The recommended way to do this is to check to see whether the machine
 * is a `Snake' first, then try System Map, then try PAT.  We try System
 * Map before checking for a Snake -- this probably doesn't cause any
 * problems, but...
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <asm/hardware.h>
#include <asm/io.h>
#include <asm/mmzone.h>
#include <asm/pdc.h>
#include <asm/pdcpat.h>
#include <asm/processor.h>
#include <asm/page.h>
#include <asm/parisc-device.h>
#include <asm/tlbflush.h>

/*
** Debug options
** DEBUG_PAT Dump details which PDC PAT provides about ranges/devices.
*/
#undef DEBUG_PAT

int pdc_type __ro_after_init = PDC_TYPE_ILLEGAL;

/* cell number and location (PAT firmware only) */
unsigned long parisc_cell_num __ro_after_init;
unsigned long parisc_cell_loc __ro_after_init;
unsigned long parisc_pat_pdc_cap __ro_after_init;


void __init setup_pdc(void)
{
	long status;
	unsigned int bus_id;
	struct pdc_system_map_mod_info module_result;
	struct pdc_module_path module_path;
	struct pdc_model model;
#ifdef CONFIG_64BIT
	struct pdc_pat_cell_num cell_info;
#endif

	/* Determine the pdc "type" used on this machine */

	printk(KERN_INFO "Determining PDC firmware type: ");

	status = pdc_system_map_find_mods(&module_result, &module_path, 0);
	if (status == PDC_OK) {
		pdc_type = PDC_TYPE_SYSTEM_MAP;
		pr_cont("System Map.\n");
		return;
	}

	/*
	 * If the machine doesn't support PDC_SYSTEM_MAP then either it
	 * is a pdc pat box, or it is an older box. All 64 bit capable
	 * machines are either pdc pat boxes or they support PDC_SYSTEM_MAP.
	 */

	/*
	 * TODO: We should test for 64 bit capability and give a
	 * clearer message.
	 */

#ifdef CONFIG_64BIT
	status = pdc_pat_cell_get_number(&cell_info);
	if (status == PDC_OK) {
		unsigned long legacy_rev, pat_rev;
		pdc_type = PDC_TYPE_PAT;
		pr_cont("64 bit PAT.\n");
		parisc_cell_num = cell_info.cell_num;
		parisc_cell_loc = cell_info.cell_loc;
		pr_info("PAT: Running on cell %lu and location %lu.\n",
			parisc_cell_num, parisc_cell_loc);
		status = pdc_pat_pd_get_pdc_revisions(&legacy_rev,
			&pat_rev, &parisc_pat_pdc_cap);
		pr_info("PAT: legacy revision 0x%lx, pat_rev 0x%lx, pdc_cap 0x%lx, S-PTLB %d, HPMC_RENDEZ %d.\n",
			legacy_rev, pat_rev, parisc_pat_pdc_cap,
			parisc_pat_pdc_cap
			 & PDC_PAT_CAPABILITY_BIT_SIMULTANEOUS_PTLB ? 1:0,
			parisc_pat_pdc_cap
			 & PDC_PAT_CAPABILITY_BIT_PDC_HPMC_RENDEZ   ? 1:0);
		return;
	}
#endif

	/* Check the CPU's bus ID.  There's probably a better test.  */

	status = pdc_model_info(&model);

	bus_id = (model.hversion >> (4 + 7)) & 0x1f;

	switch (bus_id) {
	case 0x4:		/* 720, 730, 750, 735, 755 */
	case 0x6:		/* 705, 710 */
	case 0x7:		/* 715, 725 */
	case 0x8:		/* 745, 747, 742 */
	case 0xA:		/* 712 and similar */
	case 0xC:		/* 715/64, at least */

		pdc_type = PDC_TYPE_SNAKE;
		pr_cont("Snake.\n");
		return;

	default:		/* Everything else */

		pr_cont("Unsupported.\n");
		panic("If this is a 64-bit machine, please try a 64-bit kernel.\n");
	}
}

#define PDC_PAGE_ADJ_SHIFT (PAGE_SHIFT - 12) /* pdc pages are always 4k */

static void __init
set_pmem_entry(physmem_range_t *pmem_ptr, unsigned long start,
	       unsigned long pages4k)
{
	/* Rather than aligning and potentially throwing away
	 * memory, we'll assume that any ranges are already
	 * nicely aligned with any reasonable page size, and
	 * panic if they are not (it's more likely that the
	 * pdc info is bad in this case).
	 */

	if (unlikely( ((start & (PAGE_SIZE - 1)) != 0)
	    || ((pages4k & ((1UL << PDC_PAGE_ADJ_SHIFT) - 1)) != 0) )) {

		panic("Memory range doesn't align with page size!\n");
	}

	pmem_ptr->start_pfn = (start >> PAGE_SHIFT);
	pmem_ptr->pages = (pages4k >> PDC_PAGE_ADJ_SHIFT);
}

static void __init pagezero_memconfig(void)
{
	unsigned long npages;

	/* Use the 32 bit information from page zero to create a single
	 * entry in the pmem_ranges[] table.
	 *
	 * We currently don't support machines with contiguous memory
	 * >= 4 Gb, who report that memory using 64 bit only fields
	 * on page zero. It's not worth doing until it can be tested,
	 * and it is not clear we can support those machines for other
	 * reasons.
	 *
	 * If that support is done in the future, this is where it
	 * should be done.
	 */

	npages = (PAGE_ALIGN(PAGE0->imm_max_mem) >> PAGE_SHIFT);
	set_pmem_entry(pmem_ranges,0UL,npages);
	npmem_ranges = 1;
}

#ifdef CONFIG_64BIT

/* All of the PDC PAT specific code is 64-bit only */

/*
**  The module object is filled via PDC_PAT_CELL[Return Cell Module].
**  If a module is found, register module will get the IODC bytes via
**  pdc_iodc_read() using the PA view of conf_base_addr for the hpa parameter.
**
**  The IO view can be used by PDC_PAT_CELL[Return Cell Module]
**  only for SBAs and LBAs.  This view will cause an invalid
**  argument error for all other cell module types.
**
*/

static int __init 
pat_query_module(ulong pcell_loc, ulong mod_index)
{
	pdc_pat_cell_mod_maddr_block_t *pa_pdc_cell;
	unsigned long bytecnt;
	unsigned long temp;	/* 64-bit scratch value */
	long status;		/* PDC return value status */
	struct parisc_device *dev;

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

	/* return cell module (PA or Processor view) */
	status = pdc_pat_cell_module(&bytecnt, pcell_loc, mod_index,
				     PA_VIEW, pa_pdc_cell);

	if (status != PDC_OK) {
		/* no more cell modules or error */
		kfree(pa_pdc_cell);
		return status;
	}

	temp = pa_pdc_cell->cba;
	dev = alloc_pa_dev(PAT_GET_CBA(temp), &(pa_pdc_cell->mod_path));
	if (!dev) {
		kfree(pa_pdc_cell);
		return PDC_OK;
	}

	/* alloc_pa_dev sets dev->hpa */

	/*
	** save parameters in the parisc_device
	** (The idea being the device driver will call pdc_pat_cell_module()
	** and store the results in its own data structure.)
	*/
	dev->pcell_loc = pcell_loc;
	dev->mod_index = mod_index;

	/* save generic info returned from the call */
	/* REVISIT: who is the consumer of this? not sure yet... */
	dev->mod_info = pa_pdc_cell->mod_info;	/* pass to PAT_GET_ENTITY() */
	dev->pmod_loc = pa_pdc_cell->mod_location;
	dev->mod0 = pa_pdc_cell->mod[0];

	register_parisc_device(dev);	/* advertise device */

#ifdef DEBUG_PAT
	/* dump what we see so far... */
	switch (PAT_GET_ENTITY(dev->mod_info)) {
		pdc_pat_cell_mod_maddr_block_t io_pdc_cell;
		unsigned long i;

	case PAT_ENTITY_PROC:
		printk(KERN_DEBUG "PAT_ENTITY_PROC: id_eid 0x%lx\n",
			pa_pdc_cell->mod[0]);
		break;

	case PAT_ENTITY_MEM:
		printk(KERN_DEBUG 
			"PAT_ENTITY_MEM: amount 0x%lx min_gni_base 0x%lx min_gni_len 0x%lx\n",
			pa_pdc_cell->mod[0], pa_pdc_cell->mod[1],
			pa_pdc_cell->mod[2]);
		break;
	case PAT_ENTITY_CA:
		printk(KERN_DEBUG "PAT_ENTITY_CA: %ld\n", pcell_loc);
		break;

	case PAT_ENTITY_PBC:
		printk(KERN_DEBUG "PAT_ENTITY_PBC: ");
		goto print_ranges;

	case PAT_ENTITY_SBA:
		printk(KERN_DEBUG "PAT_ENTITY_SBA: ");
		goto print_ranges;

	case PAT_ENTITY_LBA:
		printk(KERN_DEBUG "PAT_ENTITY_LBA: ");

 print_ranges:
		pdc_pat_cell_module(&bytecnt, pcell_loc, mod_index,
				    IO_VIEW, &io_pdc_cell);
		printk(KERN_DEBUG "ranges %ld\n", pa_pdc_cell->mod[1]);
		for (i = 0; i < pa_pdc_cell->mod[1]; i++) {
			printk(KERN_DEBUG 
				"  PA_VIEW %ld: 0x%016lx 0x%016lx 0x%016lx\n", 
				i, pa_pdc_cell->mod[2 + i * 3],	/* type */
				pa_pdc_cell->mod[3 + i * 3],	/* start */
				pa_pdc_cell->mod[4 + i * 3]);	/* finish (ie end) */
			printk(KERN_DEBUG 
				"  IO_VIEW %ld: 0x%016lx 0x%016lx 0x%016lx\n", 
				i, io_pdc_cell.mod[2 + i * 3],	/* type */
				io_pdc_cell.mod[3 + i * 3],	/* start */
				io_pdc_cell.mod[4 + i * 3]);	/* finish (ie end) */
		}
		printk(KERN_DEBUG "\n");
		break;
	}
#endif /* DEBUG_PAT */

	kfree(pa_pdc_cell);

	return PDC_OK;
}


/* pat pdc can return information about a variety of different
 * types of memory (e.g. firmware,i/o, etc) but we only care about
 * the usable physical ram right now. Since the firmware specific
 * information is allocated on the stack, we'll be generous, in
 * case there is a lot of other information we don't care about.
 */

#define PAT_MAX_RANGES (4 * MAX_PHYSMEM_RANGES)

static void __init pat_memconfig(void)
{
	unsigned long actual_len;
	struct pdc_pat_pd_addr_map_entry mem_table[PAT_MAX_RANGES+1];
	struct pdc_pat_pd_addr_map_entry *mtbl_ptr;
	physmem_range_t *pmem_ptr;
	long status;
	int entries;
	unsigned long length;
	int i;

	length = (PAT_MAX_RANGES + 1) * sizeof(struct pdc_pat_pd_addr_map_entry);

	status = pdc_pat_pd_get_addr_map(&actual_len, mem_table, length, 0L);

	if ((status != PDC_OK)
	    || ((actual_len % sizeof(struct pdc_pat_pd_addr_map_entry)) != 0)) {

		/* The above pdc call shouldn't fail, but, just in
		 * case, just use the PAGE0 info.
		 */

		printk("\n\n\n");
		printk(KERN_WARNING "WARNING! Could not get full memory configuration. "
			"All memory may not be used!\n\n\n");
		pagezero_memconfig();
		return;
	}

	entries = actual_len / sizeof(struct pdc_pat_pd_addr_map_entry);

	if (entries > PAT_MAX_RANGES) {
		printk(KERN_WARNING "This Machine has more memory ranges than we support!\n");
		printk(KERN_WARNING "Some memory may not be used!\n");
	}

	/* Copy information into the firmware independent pmem_ranges
	 * array, skipping types we don't care about. Notice we said
	 * "may" above. We'll use all the entries that were returned.
	 */

	npmem_ranges = 0;
	mtbl_ptr = mem_table;
	pmem_ptr = pmem_ranges; /* Global firmware independent table */
	for (i = 0; i < entries; i++,mtbl_ptr++) {
		if (   (mtbl_ptr->entry_type != PAT_MEMORY_DESCRIPTOR)
		    || (mtbl_ptr->memory_type != PAT_MEMTYPE_MEMORY)
		    || (mtbl_ptr->pages == 0)
		    || (   (mtbl_ptr->memory_usage != PAT_MEMUSE_GENERAL)
			&& (mtbl_ptr->memory_usage != PAT_MEMUSE_GI)
			&& (mtbl_ptr->memory_usage != PAT_MEMUSE_GNI) ) ) {

			continue;
		}

		if (npmem_ranges == MAX_PHYSMEM_RANGES) {
			printk(KERN_WARNING "This Machine has more memory ranges than we support!\n");
			printk(KERN_WARNING "Some memory will not be used!\n");
			break;
		}

		set_pmem_entry(pmem_ptr++,mtbl_ptr->paddr,mtbl_ptr->pages);
		npmem_ranges++;
	}
}

static int __init pat_inventory(void)
{
	int status;
	ulong mod_index = 0;
	struct pdc_pat_cell_num cell_info;

	/*
	** Note:  Prelude (and it's successors: Lclass, A400/500) only
	**        implement PDC_PAT_CELL sub-options 0 and 2.
	*/
	status = pdc_pat_cell_get_number(&cell_info);
	if (status != PDC_OK) {
		return 0;
	}

#ifdef DEBUG_PAT
	printk(KERN_DEBUG "CELL_GET_NUMBER: 0x%lx 0x%lx\n", cell_info.cell_num, 
	       cell_info.cell_loc);
#endif

	while (PDC_OK == pat_query_module(cell_info.cell_loc, mod_index)) {
		mod_index++;
	}

	return mod_index;
}

/* We only look for extended memory ranges on a 64 bit capable box */
static void __init sprockets_memconfig(void)
{
	struct pdc_memory_table_raddr r_addr;
	struct pdc_memory_table mem_table[MAX_PHYSMEM_RANGES];
	struct pdc_memory_table *mtbl_ptr;
	physmem_range_t *pmem_ptr;
	long status;
	int entries;
	int i;

	status = pdc_mem_mem_table(&r_addr,mem_table,
				(unsigned long)MAX_PHYSMEM_RANGES);

	if (status != PDC_OK) {

		/* The above pdc call only works on boxes with sprockets
		 * firmware (newer B,C,J class). Other non PAT PDC machines
		 * do support more than 3.75 Gb of memory, but we don't
		 * support them yet.
		 */

		pagezero_memconfig();
		return;
	}

	if (r_addr.entries_total > MAX_PHYSMEM_RANGES) {
		printk(KERN_WARNING "This Machine has more memory ranges than we support!\n");
		printk(KERN_WARNING "Some memory will not be used!\n");
	}

	entries = (int)r_addr.entries_returned;

	npmem_ranges = 0;
	mtbl_ptr = mem_table;
	pmem_ptr = pmem_ranges; /* Global firmware independent table */
	for (i = 0; i < entries; i++,mtbl_ptr++) {
		set_pmem_entry(pmem_ptr++,mtbl_ptr->paddr,mtbl_ptr->pages);
		npmem_ranges++;
	}
}

#else   /* !CONFIG_64BIT */

#define pat_inventory() do { } while (0)
#define pat_memconfig() do { } while (0)
#define sprockets_memconfig() pagezero_memconfig()

#endif	/* !CONFIG_64BIT */


#ifndef CONFIG_PA20

/* Code to support Snake machines (7[2350], 7[235]5, 715/Scorpio) */

static struct parisc_device * __init
legacy_create_device(struct pdc_memory_map *r_addr,
		struct pdc_module_path *module_path)
{
	struct parisc_device *dev;
	int status = pdc_mem_map_hpa(r_addr, module_path);
	if (status != PDC_OK)
		return NULL;

	dev = alloc_pa_dev(r_addr->hpa, &module_path->path);
	if (dev == NULL)
		return NULL;

	register_parisc_device(dev);
	return dev;
}

/**
 * snake_inventory
 *
 * Before PDC_SYSTEM_MAP was invented, the PDC_MEM_MAP call was used.
 * To use it, we initialise the mod_path.bc to 0xff and try all values of
 * mod to get the HPA for the top-level devices.  Bus adapters may have
 * sub-devices which are discovered by setting bc[5] to 0 and bc[4] to the
 * module, then trying all possible functions.
 */
static void __init snake_inventory(void)
{
	int mod;
	for (mod = 0; mod < 16; mod++) {
		struct parisc_device *dev;
		struct pdc_module_path module_path;
		struct pdc_memory_map r_addr;
		unsigned int func;

		memset(module_path.path.bc, 0xff, 6);
		module_path.path.mod = mod;
		dev = legacy_create_device(&r_addr, &module_path);
		if ((!dev) || (dev->id.hw_type != HPHW_BA))
			continue;

		memset(module_path.path.bc, 0xff, 4);
		module_path.path.bc[4] = mod;

		for (func = 0; func < 16; func++) {
			module_path.path.bc[5] = 0;
			module_path.path.mod = func;
			legacy_create_device(&r_addr, &module_path);
		}
	}
}

#else /* CONFIG_PA20 */
#define snake_inventory() do { } while (0)
#endif  /* CONFIG_PA20 */

/* Common 32/64 bit based code goes here */

/**
 * add_system_map_addresses - Add additional addresses to the parisc device.
 * @dev: The parisc device.
 * @num_addrs: Then number of addresses to add;
 * @module_instance: The system_map module instance.
 *
 * This function adds any additional addresses reported by the system_map
 * firmware to the parisc device.
 */
static void __init
add_system_map_addresses(struct parisc_device *dev, int num_addrs, 
			 int module_instance)
{
	int i;
	long status;
	struct pdc_system_map_addr_info addr_result;

	dev->addr = kmalloc_array(num_addrs, sizeof(*dev->addr), GFP_KERNEL);
	if(!dev->addr) {
		printk(KERN_ERR "%s %s(): memory allocation failure\n",
		       __FILE__, __func__);
		return;
	}

	for(i = 1; i <= num_addrs; ++i) {
		status = pdc_system_map_find_addrs(&addr_result, 
						   module_instance, i);
		if(PDC_OK == status) {
			dev->addr[dev->num_addrs] = (unsigned long)addr_result.mod_addr;
			dev->num_addrs++;
		} else {
			printk(KERN_WARNING 
			       "Bad PDC_FIND_ADDRESS status return (%ld) for index %d\n",
			       status, i);
		}
	}
}

/**
 * system_map_inventory - Retrieve firmware devices via SYSTEM_MAP.
 *
 * This function attempts to retrieve and register all the devices firmware
 * knows about via the SYSTEM_MAP PDC call.
 */
static void __init system_map_inventory(void)
{
	int i;
	long status = PDC_OK;
    
	for (i = 0; i < 256; i++) {
		struct parisc_device *dev;
		struct pdc_system_map_mod_info module_result;
		struct pdc_module_path module_path;

		status = pdc_system_map_find_mods(&module_result,
				&module_path, i);
		if ((status == PDC_BAD_PROC) || (status == PDC_NE_MOD))
			break;
		if (status != PDC_OK)
			continue;

		dev = alloc_pa_dev(module_result.mod_addr, &module_path.path);
		if (!dev)
			continue;
		
		register_parisc_device(dev);

		/* if available, get the additional addresses for a module */
		if (!module_result.add_addrs)
			continue;

		add_system_map_addresses(dev, module_result.add_addrs, i);
	}

	walk_central_bus();
	return;
}

void __init do_memory_inventory(void)
{
	switch (pdc_type) {

	case PDC_TYPE_PAT:
		pat_memconfig();
		break;

	case PDC_TYPE_SYSTEM_MAP:
		sprockets_memconfig();
		break;

	case PDC_TYPE_SNAKE:
		pagezero_memconfig();
		return;

	default:
		panic("Unknown PDC type!\n");
	}

	if (npmem_ranges == 0 || pmem_ranges[0].start_pfn != 0) {
		printk(KERN_WARNING "Bad memory configuration returned!\n");
		printk(KERN_WARNING "Some memory may not be used!\n");
		pagezero_memconfig();
	}
}

void __init do_device_inventory(void)
{
	printk(KERN_INFO "Searching for devices...\n");

	init_parisc_bus();

	switch (pdc_type) {

	case PDC_TYPE_PAT:
		pat_inventory();
		break;

	case PDC_TYPE_SYSTEM_MAP:
		system_map_inventory();
		break;

	case PDC_TYPE_SNAKE:
		snake_inventory();
		break;

	default:
		panic("Unknown PDC type!\n");
	}
	printk(KERN_INFO "Found devices:\n");
	print_parisc_devices();

#if defined(CONFIG_64BIT) && defined(CONFIG_SMP)
	pa_serialize_tlb_flushes = machine_has_merced_bus();
	if (pa_serialize_tlb_flushes)
		pr_info("Merced bus found: Enable PxTLB serialization.\n");
#endif
}