swh:1:snp:32555a3fd8878f019c2ebd6c964bc1edcaeff337
Tip revision: 7d2a07b769330c34b4deabeed939325c77a7ec2f authored by Linus Torvalds on 29 August 2021, 22:04:50 UTC
Linux 5.14
Linux 5.14
Tip revision: 7d2a07b
oflib.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) Paul Mackerras 1997.
*/
#include <stddef.h>
#include "types.h"
#include "elf.h"
#include "string.h"
#include "stdio.h"
#include "page.h"
#include "ops.h"
#include "of.h"
typedef u32 prom_arg_t;
/* The following structure is used to communicate with open firmware.
* All arguments in and out are in big endian format. */
struct prom_args {
__be32 service; /* Address of service name string. */
__be32 nargs; /* Number of input arguments. */
__be32 nret; /* Number of output arguments. */
__be32 args[10]; /* Input/output arguments. */
};
#ifdef __powerpc64__
extern int prom(void *);
#else
static int (*prom) (void *);
#endif
void of_init(void *promptr)
{
#ifndef __powerpc64__
prom = (int (*)(void *))promptr;
#endif
}
#define ADDR(x) (u32)(unsigned long)(x)
int of_call_prom(const char *service, int nargs, int nret, ...)
{
int i;
struct prom_args args;
va_list list;
args.service = cpu_to_be32(ADDR(service));
args.nargs = cpu_to_be32(nargs);
args.nret = cpu_to_be32(nret);
va_start(list, nret);
for (i = 0; i < nargs; i++)
args.args[i] = cpu_to_be32(va_arg(list, prom_arg_t));
va_end(list);
for (i = 0; i < nret; i++)
args.args[nargs+i] = 0;
if (prom(&args) < 0)
return PROM_ERROR;
return (nret > 0) ? be32_to_cpu(args.args[nargs]) : 0;
}
static int of_call_prom_ret(const char *service, int nargs, int nret,
prom_arg_t *rets, ...)
{
int i;
struct prom_args args;
va_list list;
args.service = cpu_to_be32(ADDR(service));
args.nargs = cpu_to_be32(nargs);
args.nret = cpu_to_be32(nret);
va_start(list, rets);
for (i = 0; i < nargs; i++)
args.args[i] = cpu_to_be32(va_arg(list, prom_arg_t));
va_end(list);
for (i = 0; i < nret; i++)
args.args[nargs+i] = 0;
if (prom(&args) < 0)
return PROM_ERROR;
if (rets != NULL)
for (i = 1; i < nret; ++i)
rets[i-1] = be32_to_cpu(args.args[nargs+i]);
return (nret > 0) ? be32_to_cpu(args.args[nargs]) : 0;
}
/* returns true if s2 is a prefix of s1 */
static int string_match(const char *s1, const char *s2)
{
for (; *s2; ++s2)
if (*s1++ != *s2)
return 0;
return 1;
}
/*
* Older OF's require that when claiming a specific range of addresses,
* we claim the physical space in the /memory node and the virtual
* space in the chosen mmu node, and then do a map operation to
* map virtual to physical.
*/
static int need_map = -1;
static ihandle chosen_mmu;
static ihandle memory;
static int check_of_version(void)
{
phandle oprom, chosen;
char version[64];
oprom = of_finddevice("/openprom");
if (oprom == (phandle) -1)
return 0;
if (of_getprop(oprom, "model", version, sizeof(version)) <= 0)
return 0;
version[sizeof(version)-1] = 0;
printf("OF version = '%s'\r\n", version);
if (!string_match(version, "Open Firmware, 1.")
&& !string_match(version, "FirmWorks,3."))
return 0;
chosen = of_finddevice("/chosen");
if (chosen == (phandle) -1) {
chosen = of_finddevice("/chosen@0");
if (chosen == (phandle) -1) {
printf("no chosen\n");
return 0;
}
}
if (of_getprop(chosen, "mmu", &chosen_mmu, sizeof(chosen_mmu)) <= 0) {
printf("no mmu\n");
return 0;
}
memory = of_call_prom("open", 1, 1, "/memory");
if (memory == PROM_ERROR) {
memory = of_call_prom("open", 1, 1, "/memory@0");
if (memory == PROM_ERROR) {
printf("no memory node\n");
return 0;
}
}
printf("old OF detected\r\n");
return 1;
}
unsigned int of_claim(unsigned long virt, unsigned long size,
unsigned long align)
{
int ret;
prom_arg_t result;
if (need_map < 0)
need_map = check_of_version();
if (align || !need_map)
return of_call_prom("claim", 3, 1, virt, size, align);
ret = of_call_prom_ret("call-method", 5, 2, &result, "claim", memory,
align, size, virt);
if (ret != 0 || result == -1)
return -1;
ret = of_call_prom_ret("call-method", 5, 2, &result, "claim", chosen_mmu,
align, size, virt);
/* 0x12 == coherent + read/write */
ret = of_call_prom("call-method", 6, 1, "map", chosen_mmu,
0x12, size, virt, virt);
return virt;
}
void *of_vmlinux_alloc(unsigned long size)
{
unsigned long start = (unsigned long)_start, end = (unsigned long)_end;
unsigned long addr;
void *p;
/* With some older POWER4 firmware we need to claim the area the kernel
* will reside in. Newer firmwares don't need this so we just ignore
* the return value.
*/
addr = (unsigned long) of_claim(start, end - start, 0);
printf("Trying to claim from 0x%lx to 0x%lx (0x%lx) got %lx\r\n",
start, end, end - start, addr);
p = malloc(size);
if (!p)
fatal("Can't allocate memory for kernel image!\n\r");
return p;
}
void of_exit(void)
{
of_call_prom("exit", 0, 0);
}
/*
* OF device tree routines
*/
void *of_finddevice(const char *name)
{
return (void *) (unsigned long) of_call_prom("finddevice", 1, 1, name);
}
int of_getprop(const void *phandle, const char *name, void *buf,
const int buflen)
{
return of_call_prom("getprop", 4, 1, phandle, name, buf, buflen);
}
int of_setprop(const void *phandle, const char *name, const void *buf,
const int buflen)
{
return of_call_prom("setprop", 4, 1, phandle, name, buf, buflen);
}