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Diffstat (limited to 'arch/powerpc/boot/oflib.c')
| -rw-r--r-- | arch/powerpc/boot/oflib.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/arch/powerpc/boot/oflib.c b/arch/powerpc/boot/oflib.c new file mode 100644 index 000000000..8759c985e --- /dev/null +++ b/arch/powerpc/boot/oflib.c @@ -0,0 +1,219 @@ +// 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); +} |