prom.c

ARM 嵌入式 系统 设计与实例开发 实验教材 二源码

/*
 * BK Id: SCCS/s.prom.c 1.48 12/19/01 10:50:58 paulus
 */
/*
 * Procedures for interfacing to the Open Firmware PROM on
 * Power Macintosh computers.
 *
 * In particular, we are interested in the device tree
 * and in using some of its services (exit, write to stdout).
 *
 * Paul Mackerras	August 1996.
 * Copyright (C) 1996 Paul Mackerras.
 */
#include <stdarg.h>
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/version.h>
#include <linux/threads.h>
#include <linux/spinlock.h>
#include <linux/ioport.h>
#include <linux/pci.h>
#include <linux/slab.h>

#include <asm/sections.h>
#include <asm/prom.h>
#include <asm/page.h>
#include <asm/processor.h>
#include <asm/irq.h>
#include <asm/io.h>
#include <asm/smp.h>
#include <asm/bootx.h>
#include <asm/system.h>
#include <asm/mmu.h>
#include <asm/pgtable.h>
#include <asm/bitops.h>
#include <asm/bootinfo.h>
#include <asm/btext.h>
#include <asm/pci-bridge.h>
#include "open_pic.h"

#ifdef CONFIG_FB
#include <asm/linux_logo.h>
#endif

/*
 * Properties whose value is longer than this get excluded from our
 * copy of the device tree.  This way we don't waste space storing
 * things like "driver,AAPL,MacOS,PowerPC" properties.  But this value
 * does need to be big enough to ensure that we don't lose things
 * like the interrupt-map property on a PCI-PCI bridge.
 */
#define MAX_PROPERTY_LENGTH	4096

struct prom_args {
	const char *service;
	int nargs;
	int nret;
	void *args[10];
};

struct pci_address {
	unsigned a_hi;
	unsigned a_mid;
	unsigned a_lo;
};

struct pci_reg_property {
	struct pci_address addr;
	unsigned size_hi;
	unsigned size_lo;
};

struct pci_range {
	struct pci_address addr;
	unsigned phys;
	unsigned size_hi;
	unsigned size_lo;
};

struct isa_reg_property {
	unsigned space;
	unsigned address;
	unsigned size;
};

struct pci_intr_map {
	struct pci_address addr;
	unsigned dunno;
	phandle int_ctrler;
	unsigned intr;
};

typedef unsigned long interpret_func(struct device_node *, unsigned long,
				     int, int);
static interpret_func interpret_pci_props;
static interpret_func interpret_dbdma_props;
static interpret_func interpret_isa_props;
static interpret_func interpret_macio_props;
static interpret_func interpret_root_props;

#ifndef FB_MAX			/* avoid pulling in all of the fb stuff */
#define FB_MAX	8
#endif
char *prom_display_paths[FB_MAX] __initdata = { 0, };
phandle prom_display_nodes[FB_MAX] __initdata;
unsigned int prom_num_displays __initdata = 0;
char *of_stdout_device __initdata = 0;
ihandle prom_disp_node __initdata = 0;

prom_entry prom __initdata = 0;
ihandle prom_chosen __initdata = 0;
ihandle prom_stdout __initdata = 0;

extern char *klimit;
char *bootpath;
char *bootdevice;

unsigned int rtas_data;   /* physical pointer */
unsigned int rtas_entry;  /* physical pointer */
unsigned int rtas_size;
unsigned int old_rtas;

/* Set for a newworld or CHRP machine */
int use_of_interrupt_tree;
struct device_node *dflt_interrupt_controller;
int num_interrupt_controllers;

int pmac_newworld;

static struct device_node *allnodes;

static void *call_prom(const char *service, int nargs, int nret, ...);
static void prom_exit(void);
static unsigned long copy_device_tree(unsigned long, unsigned long);
static unsigned long inspect_node(phandle, struct device_node *, unsigned long,
				  unsigned long, struct device_node ***);
static unsigned long finish_node(struct device_node *, unsigned long,
				 interpret_func *, int, int);
static unsigned long finish_node_interrupts(struct device_node *, unsigned long);
static unsigned long check_display(unsigned long);
static int prom_next_node(phandle *);
static void *early_get_property(unsigned long, unsigned long, char *);
static struct device_node *find_phandle(phandle);

#ifdef CONFIG_BOOTX_TEXT
static void setup_disp_fake_bi(ihandle dp);
#endif

extern void enter_rtas(void *);
void phys_call_rtas(int, int, int, ...);

extern char cmd_line[512];	/* XXX */
boot_infos_t *boot_infos;
unsigned long dev_tree_size;

#define ALIGN(x) (((x) + sizeof(unsigned long)-1) & -sizeof(unsigned long))

/* Is boot-info compatible ? */
#define BOOT_INFO_IS_COMPATIBLE(bi)		((bi)->compatible_version <= BOOT_INFO_VERSION)
#define BOOT_INFO_IS_V2_COMPATIBLE(bi)	((bi)->version >= 2)
#define BOOT_INFO_IS_V4_COMPATIBLE(bi)	((bi)->version >= 4)

/*
 * Note that prom_init() and anything called from prom_init() must
 * use the RELOC/PTRRELOC macros to access any static data in
 * memory, since the kernel may be running at an address that is
 * different from the address that it was linked at.
 * (Note that strings count as static variables.)
 */

static void __init
prom_exit()
{
	struct prom_args args;
	unsigned long offset = reloc_offset();

	args.service = "exit";
	args.nargs = 0;
	args.nret = 0;
	RELOC(prom)(&args);
	for (;;)			/* should never get here */
		;
}

void __init
prom_enter(void)
{
	struct prom_args args;
	unsigned long offset = reloc_offset();

	args.service = RELOC("enter");
	args.nargs = 0;
	args.nret = 0;
	RELOC(prom)(&args);
}

static void * __init
call_prom(const char *service, int nargs, int nret, ...)
{
	va_list list;
	int i;
	unsigned long offset = reloc_offset();
	struct prom_args prom_args;

	prom_args.service = service;
	prom_args.nargs = nargs;
	prom_args.nret = nret;
	va_start(list, nret);
	for (i = 0; i < nargs; ++i)
		prom_args.args[i] = va_arg(list, void *);
	va_end(list);
	for (i = 0; i < nret; ++i)
		prom_args.args[i + nargs] = 0;
	RELOC(prom)(&prom_args);
	return prom_args.args[nargs];
}

void __init
prom_print(const char *msg)
{
	const char *p, *q;
	unsigned long offset = reloc_offset();

	if (RELOC(prom_stdout) == 0)
		return;

	for (p = msg; *p != 0; p = q) {
		for (q = p; *q != 0 && *q != '\n'; ++q)
			;
		if (q > p)
			call_prom(RELOC("write"), 3, 1, RELOC(prom_stdout),
				  p, q - p);
		if (*q != 0) {
			++q;
			call_prom(RELOC("write"), 3, 1, RELOC(prom_stdout),
				  RELOC("\r\n"), 2);
		}
	}
}

static void __init
prom_print_hex(unsigned int v)
{
	char buf[16];
	int i, c;

	for (i = 0; i < 8; ++i) {
		c = (v >> ((7-i)*4)) & 0xf;
		c += (c >= 10)? ('a' - 10): '0';
		buf[i] = c;
	}
	buf[i] = ' ';
	buf[i+1] = 0;
	prom_print(buf);
}

unsigned long smp_chrp_cpu_nr __initdata = 0;

#ifdef CONFIG_SMP
/*
 * With CHRP SMP we need to use the OF to start the other
 * processors so we can't wait until smp_boot_cpus (the OF is
 * trashed by then) so we have to put the processors into
 * a holding pattern controlled by the kernel (not OF) before
 * we destroy the OF.
 *
 * This uses a chunk of high memory, puts some holding pattern
 * code there and sends the other processors off to there until
 * smp_boot_cpus tells them to do something.  We do that by using
 * physical address 0x0.  The holding pattern checks that address
 * until its cpu # is there, when it is that cpu jumps to
 * __secondary_start().  smp_boot_cpus() takes care of setting those
 * values.
 *
 * We also use physical address 0x4 here to tell when a cpu
 * is in its holding pattern code.
 *
 * -- Cort
 */
static void __init
prom_hold_cpus(unsigned long mem)
{
	extern void __secondary_hold(void);
	unsigned long i;
	int cpu;
	phandle node;
	unsigned long offset = reloc_offset();
	char type[16], *path;
	unsigned int reg;

	/*
	 * XXX: hack to make sure we're chrp, assume that if we're
	 *      chrp we have a device_type property -- Cort
	 */
	node = call_prom(RELOC("finddevice"), 1, 1, RELOC("/"));
	if ( (int)call_prom(RELOC("getprop"), 4, 1, node,
			    RELOC("device_type"),type, sizeof(type)) <= 0)
		return;

	/* copy the holding pattern code to someplace safe (0) */
	/* the holding pattern is now within the first 0x100
	   bytes of the kernel image -- paulus */
	memcpy((void *)0, (void *)(KERNELBASE + offset), 0x100);
	flush_icache_range(0, 0x100);

	/* look for cpus */
	*(unsigned long *)(0x0) = 0;
	asm volatile("dcbf 0,%0": : "r" (0) : "memory");
	for (node = 0; prom_next_node(&node); ) {
		type[0] = 0;
		call_prom(RELOC("getprop"), 4, 1, node, RELOC("device_type"),
			  type, sizeof(type));
		if (strcmp(type, RELOC("cpu")) != 0)
			continue;
		path = (char *) mem;
		memset(path, 0, 256);
		if ((int) call_prom(RELOC("package-to-path"), 3, 1,
				    node, path, 255) < 0)
			continue;
		reg = -1;
		call_prom(RELOC("getprop"), 4, 1, node, RELOC("reg"),
			  &reg, sizeof(reg));
		cpu = RELOC(smp_chrp_cpu_nr)++;
		RELOC(smp_hw_index)[cpu] = reg;
		/* XXX: hack - don't start cpu 0, this cpu -- Cort */
		if (cpu == 0)
			continue;
		prom_print(RELOC("starting cpu "));
		prom_print(path);
		*(ulong *)(0x4) = 0;
		call_prom(RELOC("start-cpu"), 3, 0, node,
			  __pa(__secondary_hold), cpu);
		prom_print(RELOC("..."));
		for ( i = 0 ; (i < 10000) && (*(ulong *)(0x4) == 0); i++ )
			;
		if (*(ulong *)(0x4) == cpu)
			prom_print(RELOC("ok\n"));
		else {
			prom_print(RELOC("failed: "));
			prom_print_hex(*(ulong *)0x4);
			prom_print(RELOC("\n"));
		}
	}
}
#endif /* CONFIG_SMP */

void __init
bootx_init(unsigned long r4, unsigned long phys)
{
	boot_infos_t *bi = (boot_infos_t *) r4;
	unsigned long space;
	unsigned long ptr, x;
	char *model;
	unsigned long offset = reloc_offset();

	RELOC(boot_infos) = PTRUNRELOC(bi);
	if (!BOOT_INFO_IS_V2_COMPATIBLE(bi))
		bi->logicalDisplayBase = 0;

#ifdef CONFIG_BOOTX_TEXT
	btext_init(bi);

	/*
	 * Test if boot-info is compatible.  Done only in config
	 * CONFIG_BOOTX_TEXT since there is nothing much we can do
	 * with an incompatible version, except display a message
	 * and eventually hang the processor...
	 *
	 * I'll try to keep enough of boot-info compatible in the
	 * future to always allow display of this message;
	 */
	if (!BOOT_INFO_IS_COMPATIBLE(bi)) {
		btext_drawstring(RELOC(" !!! WARNING - Incompatible version of BootX !!!\n\n\n"));
		btext_flushscreen();
	}
#endif	/* CONFIG_BOOTX_TEXT */

	/* New BootX enters kernel with MMU off, i/os are not allowed
	   here. This hack will have been done by the boostrap anyway.
	*/
	if (bi->version < 4) {
		/*
		 * XXX If this is an iMac, turn off the USB controller.
		 */
		model = (char *) early_get_property
			(r4 + bi->deviceTreeOffset, 4, RELOC("model"));
		if (model
		    && (strcmp(model, RELOC("iMac,1")) == 0
			|| strcmp(model, RELOC("PowerMac1,1")) == 0)) {
			out_le32((unsigned *)0x80880008, 1);	/* XXX */
		}
	}

	/* Move klimit to enclose device tree, args, ramdisk, etc... */
	if (bi->version < 5) {
		space = bi->deviceTreeOffset + bi->deviceTreeSize;
		if (bi->ramDisk)
			space = bi->ramDisk + bi->ramDiskSize;
	} else
		space = bi->totalParamsSize;
	RELOC(klimit) = PTRUNRELOC((char *) bi + space);

	/* New BootX will have flushed all TLBs and enters kernel with
	   MMU switched OFF, so this should not be useful anymore.
	*/
	if (bi->version < 4) {
		/*
		 * Touch each page to make sure the PTEs for them
		 * are in the hash table - the aim is to try to avoid
		 * getting DSI exceptions while copying the kernel image.
		 */
		for (ptr = (KERNELBASE + offset) & PAGE_MASK;
		     ptr < (unsigned long)bi + space; ptr += PAGE_SIZE)
			x = *(volatile unsigned long *)ptr;
	}

#ifdef CONFIG_BOOTX_TEXT
	/*
	 * Note that after we call prepare_disp_BAT, we can't do
	 * prom_draw*, flushscreen or clearscreen until we turn the MMU
	 * on, since prepare_disp_BAT sets disp_bi->logicalDisplayBase
	 * to a virtual address.
	 */
	btext_prepare_BAT();
#endif
}

#ifdef CONFIG_PPC64BRIDGE
/*
 * Set up a hash table with a set of entries in it to map the
 * first 64MB of RAM.  This is used on 64-bit machines since
 * some of them don't have BATs.
 * We assume the PTE will fit in the primary PTEG.
 */

static inline void make_pte(unsigned long htab, unsigned int hsize,
			    unsigned int va, unsigned int pa, int mode)
{
	unsigned int *pteg;
	unsigned int hash, i, vsid;

	vsid = ((va >> 28) * 0x111) << 12;
	hash = ((va ^ vsid) >> 5) & 0x7fff80;
	pteg = (unsigned int *)(htab + (hash & (hsize - 1)));
	for (i = 0; i < 8; ++i, pteg += 4) {
		if ((pteg[1] & 1) == 0) {
			pteg[1] = vsid | ((va >> 16) & 0xf80) | 1;
			pteg[3] = pa | mode;
			break;
		}
	}
}

extern unsigned long _SDR1;
extern PTE *Hash;
extern unsigned long Hash_size;

static void __init
prom_alloc_htab(void)
{
	unsigned int hsize;
	unsigned long htab;
	unsigned int addr;
	unsigned long offset = reloc_offset();

	/*
	 * Because of OF bugs we can't use the "claim" client
	 * interface to allocate memory for the hash table.
	 * This code is only used on 64-bit PPCs, and the only
	 * 64-bit PPCs at the moment are RS/6000s, and their
	 * OF is based at 0xc00000 (the 12M point), so we just
	 * arbitrarily use the 0x800000 - 0xc00000 region for the
	 * hash table.
	 *  -- paulus.
	 */
#ifdef CONFIG_POWER4
	hsize = 4 << 20;	/* POWER4 has no BATs */
#else
	hsize = 2 << 20;
#endif /* CONFIG_POWER4 */
	htab = (8 << 20);
	RELOC(Hash) = (void *)(htab + KERNELBASE);
	RELOC(Hash_size) = hsize;
	RELOC(_SDR1) = htab + __ilog2(hsize) - 18;

	/*
	 * Put in PTEs for the first 64MB of RAM
	 */
	cacheable_memzero((void *)htab, hsize);
	for (addr = 0; addr < 0x4000000; addr += 0x1000)
		make_pte(htab, hsize, addr + KERNELBASE, addr,
			 _PAGE_ACCESSED | _PAGE_COHERENT | PP_RWXX);
}
#endif /* CONFIG_PPC64BRIDGE */

static void __init
prom_instantiate_rtas(void)
{
	ihandle prom_rtas;
	unsigned int i;
	struct prom_args prom_args;
	unsigned long offset = reloc_offset();

	prom_rtas = call_prom(RELOC("finddevice"), 1, 1, RELOC("/rtas"));
	if (prom_rtas == (void *) -1)
		return;

	RELOC(rtas_size) = 0;
	call_prom(RELOC("getprop"), 4, 1, prom_rtas,
		  RELOC("rtas-size"), &RELOC(rtas_size), sizeof(rtas_size));
	prom_print(RELOC("instantiating rtas"));
	if (RELOC(rtas_size) == 0) {
		RELOC(rtas_data) = 0;
	} else {
		/*
		 * Ask OF for some space for RTAS.
		 * Actually OF has bugs so we just arbitrarily
		 * use memory at the 6MB point.
		 */
		RELOC(rtas_data) = 6 << 20;
		prom_print(RELOC(" at "));
		prom_print_hex(RELOC(rtas_data));
	}

	prom_rtas = call_prom(RELOC("open"), 1, 1, RELOC("/rtas"));
	prom_print(RELOC("..."));
	prom_args.service = RELOC("call-method");
	prom_args.nargs = 3;
	prom_args.nret = 2;
	prom_args.args[0] = RELOC("instantiate-rtas");
	prom_args.args[1] = prom_rtas;
	prom_args.args[2] = (void *) RELOC(rtas_data);
	RELOC(prom)(&prom_args);
	i = 0;
	if (prom_args.args[3] == 0)
		i = (unsigned int)prom_args.args[4];
	RELOC(rtas_entry) = i;
	if ((RELOC(rtas_entry) == -1) || (RELOC(rtas_entry) == 0))
		prom_print(RELOC(" failed\n"));
	else
		prom_print(RELOC(" done\n"));
}