/*
 * inventory.c
 *
 * 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 of the License, or (at your option) any later version.
 *
 * 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>

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

int pdc_type __read_mostly = PDC_TYPE_ILLEGAL;

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;
                printk("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) {
                pdc_type = PDC_TYPE_PAT;
                printk("64 bit PAT.\n");
                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;
                printk("Snake.\n");
                return;

        default:                /* Everything else */

                printk("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;

        register_parisc_device(dev);    /* advertise device */

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