inventory.c

一个2.4.21版本的嵌入式linux内核

/*
 * 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/pdc.h>
#include <asm/processor.h>
#include <asm/page.h>

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

int pdc_type = 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 __LP64__
	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 __LP64__
	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 similiar */
	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 (   ((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 __LP64__

/* 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;
	pdc_pat_cell_mod_maddr_block_t io_pdc_cell;
	unsigned long bytecnt;
	unsigned long temp;	/* 64-bit scratch value */
	long status;		/* PDC return value status */
	struct parisc_device *dev;

	/* 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 */
		return status;
	}

	temp = pa_pdc_cell.cba;
	dev = alloc_pa_dev(PAT_GET_CBA(temp), &pa_pdc_cell.mod_path);
	if (!dev) {
		return PDC_NE_MOD;
	}

	/* 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
	/* 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 */
	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");
	}