From: Benjamin Herrenschmidt Date: Tue, 6 Aug 2013 16:01:38 +0000 (+1000) Subject: powerpc: Make prom_init.c endian safe X-Git-Tag: upstream/snapshot3+hdmi~4413^2~43 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=493adffcb43ffd9f8f2d5485603574502fd9e01d;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git powerpc: Make prom_init.c endian safe Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt --- diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c index 57df5cb..7b6391b 100644 --- a/arch/powerpc/kernel/prom_init.c +++ b/arch/powerpc/kernel/prom_init.c @@ -107,10 +107,10 @@ int of_workarounds; typedef u32 prom_arg_t; struct prom_args { - u32 service; - u32 nargs; - u32 nret; - prom_arg_t args[10]; + __be32 service; + __be32 nargs; + __be32 nret; + __be32 args[10]; }; struct prom_t { @@ -123,11 +123,11 @@ struct prom_t { }; struct mem_map_entry { - u64 base; - u64 size; + __be64 base; + __be64 size; }; -typedef u32 cell_t; +typedef __be32 cell_t; extern void __start(unsigned long r3, unsigned long r4, unsigned long r5, unsigned long r6, unsigned long r7, unsigned long r8, @@ -219,13 +219,13 @@ static int __init call_prom(const char *service, int nargs, int nret, ...) struct prom_args args; va_list list; - args.service = ADDR(service); - args.nargs = nargs; - args.nret = nret; + 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] = va_arg(list, prom_arg_t); + args.args[i] = cpu_to_be32(va_arg(list, prom_arg_t)); va_end(list); for (i = 0; i < nret; i++) @@ -234,7 +234,7 @@ static int __init call_prom(const char *service, int nargs, int nret, ...) if (enter_prom(&args, prom_entry) < 0) return PROM_ERROR; - return (nret > 0) ? args.args[nargs] : 0; + return (nret > 0) ? be32_to_cpu(args.args[nargs]) : 0; } static int __init call_prom_ret(const char *service, int nargs, int nret, @@ -244,13 +244,13 @@ static int __init call_prom_ret(const char *service, int nargs, int nret, struct prom_args args; va_list list; - args.service = ADDR(service); - args.nargs = nargs; - args.nret = nret; + 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] = va_arg(list, prom_arg_t); + args.args[i] = cpu_to_be32(va_arg(list, prom_arg_t)); va_end(list); for (i = 0; i < nret; i++) @@ -261,9 +261,9 @@ static int __init call_prom_ret(const char *service, int nargs, int nret, if (rets != NULL) for (i = 1; i < nret; ++i) - rets[i-1] = args.args[nargs+i]; + rets[i-1] = be32_to_cpu(args.args[nargs+i]); - return (nret > 0) ? args.args[nargs] : 0; + return (nret > 0) ? be32_to_cpu(args.args[nargs]) : 0; } @@ -527,7 +527,7 @@ static int __init prom_setprop(phandle node, const char *nodename, #define islower(c) ('a' <= (c) && (c) <= 'z') #define toupper(c) (islower(c) ? ((c) - 'a' + 'A') : (c)) -unsigned long prom_strtoul(const char *cp, const char **endp) +static unsigned long prom_strtoul(const char *cp, const char **endp) { unsigned long result = 0, base = 10, value; @@ -552,7 +552,7 @@ unsigned long prom_strtoul(const char *cp, const char **endp) return result; } -unsigned long prom_memparse(const char *ptr, const char **retptr) +static unsigned long prom_memparse(const char *ptr, const char **retptr) { unsigned long ret = prom_strtoul(ptr, retptr); int shift = 0; @@ -724,7 +724,8 @@ unsigned char ibm_architecture_vec[] = { }; -/* Old method - ELF header with PT_NOTE sections */ +/* Old method - ELF header with PT_NOTE sections only works on BE */ +#ifdef __BIG_ENDIAN__ static struct fake_elf { Elf32_Ehdr elfhdr; Elf32_Phdr phdr[2]; @@ -810,6 +811,7 @@ static struct fake_elf { } } }; +#endif /* __BIG_ENDIAN__ */ static int __init prom_count_smt_threads(void) { @@ -852,9 +854,9 @@ static int __init prom_count_smt_threads(void) static void __init prom_send_capabilities(void) { - ihandle elfloader, root; + ihandle root; prom_arg_t ret; - u32 *cores; + __be32 *cores; root = call_prom("open", 1, 1, ADDR("/")); if (root != 0) { @@ -864,15 +866,15 @@ static void __init prom_send_capabilities(void) * (we assume this is the same for all cores) and use it to * divide NR_CPUS. */ - cores = (u32 *)&ibm_architecture_vec[IBM_ARCH_VEC_NRCORES_OFFSET]; - if (*cores != NR_CPUS) { + cores = (__be32 *)&ibm_architecture_vec[IBM_ARCH_VEC_NRCORES_OFFSET]; + if (be32_to_cpup(cores) != NR_CPUS) { prom_printf("WARNING ! " "ibm_architecture_vec structure inconsistent: %lu!\n", - *cores); + be32_to_cpup(cores)); } else { - *cores = DIV_ROUND_UP(NR_CPUS, prom_count_smt_threads()); + *cores = cpu_to_be32(DIV_ROUND_UP(NR_CPUS, prom_count_smt_threads())); prom_printf("Max number of cores passed to firmware: %lu (NR_CPUS = %lu)\n", - *cores, NR_CPUS); + be32_to_cpup(cores), NR_CPUS); } /* try calling the ibm,client-architecture-support method */ @@ -893,17 +895,24 @@ static void __init prom_send_capabilities(void) prom_printf(" not implemented\n"); } - /* no ibm,client-architecture-support call, try the old way */ - elfloader = call_prom("open", 1, 1, ADDR("/packages/elf-loader")); - if (elfloader == 0) { - prom_printf("couldn't open /packages/elf-loader\n"); - return; +#ifdef __BIG_ENDIAN__ + { + ihandle elfloader; + + /* no ibm,client-architecture-support call, try the old way */ + elfloader = call_prom("open", 1, 1, + ADDR("/packages/elf-loader")); + if (elfloader == 0) { + prom_printf("couldn't open /packages/elf-loader\n"); + return; + } + call_prom("call-method", 3, 1, ADDR("process-elf-header"), + elfloader, ADDR(&fake_elf)); + call_prom("close", 1, 0, elfloader); } - call_prom("call-method", 3, 1, ADDR("process-elf-header"), - elfloader, ADDR(&fake_elf)); - call_prom("close", 1, 0, elfloader); +#endif /* __BIG_ENDIAN__ */ } -#endif +#endif /* #if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_POWERNV) */ /* * Memory allocation strategy... our layout is normally: @@ -1050,11 +1059,11 @@ static unsigned long __init prom_next_cell(int s, cell_t **cellp) p++; s--; } - r = *p++; + r = be32_to_cpu(*p++); #ifdef CONFIG_PPC64 if (s > 1) { r <<= 32; - r |= *(p++); + r |= be32_to_cpu(*(p++)); } #endif *cellp = p; @@ -1087,8 +1096,8 @@ static void __init reserve_mem(u64 base, u64 size) if (cnt >= (MEM_RESERVE_MAP_SIZE - 1)) prom_panic("Memory reserve map exhausted !\n"); - mem_reserve_map[cnt].base = base; - mem_reserve_map[cnt].size = size; + mem_reserve_map[cnt].base = cpu_to_be64(base); + mem_reserve_map[cnt].size = cpu_to_be64(size); mem_reserve_cnt = cnt + 1; } @@ -1102,6 +1111,7 @@ static void __init prom_init_mem(void) char *path, type[64]; unsigned int plen; cell_t *p, *endp; + __be32 val; u32 rac, rsc; /* @@ -1109,12 +1119,14 @@ static void __init prom_init_mem(void) * 1) top of RMO (first node) * 2) top of memory */ - rac = 2; - prom_getprop(prom.root, "#address-cells", &rac, sizeof(rac)); - rsc = 1; - prom_getprop(prom.root, "#size-cells", &rsc, sizeof(rsc)); - prom_debug("root_addr_cells: %x\n", (unsigned long) rac); - prom_debug("root_size_cells: %x\n", (unsigned long) rsc); + val = cpu_to_be32(2); + prom_getprop(prom.root, "#address-cells", &val, sizeof(val)); + rac = be32_to_cpu(val); + val = cpu_to_be32(1); + prom_getprop(prom.root, "#size-cells", &val, sizeof(rsc)); + rsc = be32_to_cpu(val); + prom_debug("root_addr_cells: %x\n", rac); + prom_debug("root_size_cells: %x\n", rsc); prom_debug("scanning memory:\n"); path = prom_scratch; @@ -1222,25 +1234,23 @@ static void __init prom_init_mem(void) static void __init prom_close_stdin(void) { - ihandle val; + __be32 val; + ihandle stdin; - if (prom_getprop(prom.chosen, "stdin", &val, sizeof(val)) > 0) - call_prom("close", 1, 0, val); + if (prom_getprop(prom.chosen, "stdin", &val, sizeof(val)) > 0) { + stdin = be32_to_cpu(val); + call_prom("close", 1, 0, stdin); + } } #ifdef CONFIG_PPC_POWERNV -static u64 __initdata prom_opal_size; -static u64 __initdata prom_opal_align; -static int __initdata prom_rtas_start_cpu; -static u64 __initdata prom_rtas_data; -static u64 __initdata prom_rtas_entry; - #ifdef CONFIG_PPC_EARLY_DEBUG_OPAL static u64 __initdata prom_opal_base; static u64 __initdata prom_opal_entry; #endif +#ifdef __BIG_ENDIAN__ /* XXX Don't change this structure without updating opal-takeover.S */ static struct opal_secondary_data { s64 ack; /* 0 */ @@ -1248,6 +1258,12 @@ static struct opal_secondary_data { struct opal_takeover_args args; /* 16 */ } opal_secondary_data; +static u64 __initdata prom_opal_align; +static u64 __initdata prom_opal_size; +static int __initdata prom_rtas_start_cpu; +static u64 __initdata prom_rtas_data; +static u64 __initdata prom_rtas_entry; + extern char opal_secondary_entry; static void __init prom_query_opal(void) @@ -1265,6 +1281,7 @@ static void __init prom_query_opal(void) } prom_printf("Querying for OPAL presence... "); + rc = opal_query_takeover(&prom_opal_size, &prom_opal_align); prom_debug("(rc = %ld) ", rc); @@ -1425,6 +1442,7 @@ static void __init prom_opal_takeover(void) for (;;) opal_do_takeover(args); } +#endif /* __BIG_ENDIAN__ */ /* * Allocate room for and instantiate OPAL @@ -1435,6 +1453,7 @@ static void __init prom_instantiate_opal(void) ihandle opal_inst; u64 base, entry; u64 size = 0, align = 0x10000; + __be64 val64; u32 rets[2]; prom_debug("prom_instantiate_opal: start...\n"); @@ -1444,11 +1463,14 @@ static void __init prom_instantiate_opal(void) if (!PHANDLE_VALID(opal_node)) return; - prom_getprop(opal_node, "opal-runtime-size", &size, sizeof(size)); + val64 = 0; + prom_getprop(opal_node, "opal-runtime-size", &val64, sizeof(val64)); + size = be64_to_cpu(val64); if (size == 0) return; - prom_getprop(opal_node, "opal-runtime-alignment", &align, - sizeof(align)); + val64 = 0; + prom_getprop(opal_node, "opal-runtime-alignment", &val64,sizeof(val64)); + align = be64_to_cpu(val64); base = alloc_down(size, align, 0); if (base == 0) { @@ -1505,6 +1527,7 @@ static void __init prom_instantiate_rtas(void) phandle rtas_node; ihandle rtas_inst; u32 base, entry = 0; + __be32 val; u32 size = 0; prom_debug("prom_instantiate_rtas: start...\n"); @@ -1514,7 +1537,9 @@ static void __init prom_instantiate_rtas(void) if (!PHANDLE_VALID(rtas_node)) return; - prom_getprop(rtas_node, "rtas-size", &size, sizeof(size)); + val = 0; + prom_getprop(rtas_node, "rtas-size", &val, sizeof(size)); + size = be32_to_cpu(val); if (size == 0) return; @@ -1541,12 +1566,14 @@ static void __init prom_instantiate_rtas(void) reserve_mem(base, size); + val = cpu_to_be32(base); prom_setprop(rtas_node, "/rtas", "linux,rtas-base", - &base, sizeof(base)); + &val, sizeof(val)); + val = cpu_to_be32(entry); prom_setprop(rtas_node, "/rtas", "linux,rtas-entry", - &entry, sizeof(entry)); + &val, sizeof(val)); -#ifdef CONFIG_PPC_POWERNV +#if defined(CONFIG_PPC_POWERNV) && defined(__BIG_ENDIAN__) /* PowerVN takeover hack */ prom_rtas_data = base; prom_rtas_entry = entry; @@ -1620,6 +1647,7 @@ static void __init prom_instantiate_sml(void) /* * Allocate room for and initialize TCE tables */ +#ifdef __BIG_ENDIAN__ static void __init prom_initialize_tce_table(void) { phandle node; @@ -1748,7 +1776,8 @@ static void __init prom_initialize_tce_table(void) /* Flag the first invalid entry */ prom_debug("ending prom_initialize_tce_table\n"); } -#endif +#endif /* __BIG_ENDIAN__ */ +#endif /* CONFIG_PPC64 */ /* * With CHRP SMP we need to use the OF to start the other processors. @@ -1777,7 +1806,6 @@ static void __init prom_initialize_tce_table(void) static void __init prom_hold_cpus(void) { unsigned long i; - unsigned int reg; phandle node; char type[64]; unsigned long *spinloop @@ -1803,6 +1831,9 @@ static void __init prom_hold_cpus(void) /* look for cpus */ for (node = 0; prom_next_node(&node); ) { + unsigned int cpu_no; + __be32 reg; + type[0] = 0; prom_getprop(node, "device_type", type, sizeof(type)); if (strcmp(type, "cpu") != 0) @@ -1813,10 +1844,11 @@ static void __init prom_hold_cpus(void) if (strcmp(type, "okay") != 0) continue; - reg = -1; + reg = cpu_to_be32(-1); /* make sparse happy */ prom_getprop(node, "reg", ®, sizeof(reg)); + cpu_no = be32_to_cpu(reg); - prom_debug("cpu hw idx = %lu\n", reg); + prom_debug("cpu hw idx = %lu\n", cpu_no); /* Init the acknowledge var which will be reset by * the secondary cpu when it awakens from its OF @@ -1824,24 +1856,24 @@ static void __init prom_hold_cpus(void) */ *acknowledge = (unsigned long)-1; - if (reg != prom.cpu) { + if (cpu_no != prom.cpu) { /* Primary Thread of non-boot cpu or any thread */ - prom_printf("starting cpu hw idx %lu... ", reg); + prom_printf("starting cpu hw idx %lu... ", cpu_no); call_prom("start-cpu", 3, 0, node, - secondary_hold, reg); + secondary_hold, cpu_no); for (i = 0; (i < 100000000) && (*acknowledge == ((unsigned long)-1)); i++ ) mb(); - if (*acknowledge == reg) + if (*acknowledge == cpu_no) prom_printf("done\n"); else prom_printf("failed: %x\n", *acknowledge); } #ifdef CONFIG_SMP else - prom_printf("boot cpu hw idx %lu\n", reg); + prom_printf("boot cpu hw idx %lu\n", cpu_no); #endif /* CONFIG_SMP */ } @@ -1895,6 +1927,7 @@ static void __init prom_find_mmu(void) prom.memory = call_prom("open", 1, 1, ADDR("/memory")); prom_getprop(prom.chosen, "mmu", &prom.mmumap, sizeof(prom.mmumap)); + prom.mmumap = be32_to_cpu(prom.mmumap); if (!IHANDLE_VALID(prom.memory) || !IHANDLE_VALID(prom.mmumap)) of_workarounds &= ~OF_WA_CLAIM; /* hmmm */ } @@ -1906,17 +1939,19 @@ static void __init prom_init_stdout(void) { char *path = of_stdout_device; char type[16]; - u32 val; + phandle stdout_node; + __be32 val; if (prom_getprop(prom.chosen, "stdout", &val, sizeof(val)) <= 0) prom_panic("cannot find stdout"); - prom.stdout = val; + prom.stdout = be32_to_cpu(val); /* Get the full OF pathname of the stdout device */ memset(path, 0, 256); call_prom("instance-to-path", 3, 1, prom.stdout, path, 255); - val = call_prom("instance-to-package", 1, 1, prom.stdout); + stdout_node = call_prom("instance-to-package", 1, 1, prom.stdout); + val = cpu_to_be32(stdout_node); prom_setprop(prom.chosen, "/chosen", "linux,stdout-package", &val, sizeof(val)); prom_printf("OF stdout device is: %s\n", of_stdout_device); @@ -1925,9 +1960,9 @@ static void __init prom_init_stdout(void) /* If it's a display, note it */ memset(type, 0, sizeof(type)); - prom_getprop(val, "device_type", type, sizeof(type)); + prom_getprop(stdout_node, "device_type", type, sizeof(type)); if (strcmp(type, "display") == 0) - prom_setprop(val, path, "linux,boot-display", NULL, 0); + prom_setprop(stdout_node, path, "linux,boot-display", NULL, 0); } static int __init prom_find_machine_type(void) @@ -2133,8 +2168,10 @@ static void __init *make_room(unsigned long *mem_start, unsigned long *mem_end, return ret; } -#define dt_push_token(token, mem_start, mem_end) \ - do { *((u32 *)make_room(mem_start, mem_end, 4, 4)) = token; } while(0) +#define dt_push_token(token, mem_start, mem_end) do { \ + void *room = make_room(mem_start, mem_end, 4, 4); \ + *(__be32 *)room = cpu_to_be32(token); \ + } while(0) static unsigned long __init dt_find_string(char *str) { @@ -2307,7 +2344,7 @@ static void __init scan_dt_build_struct(phandle node, unsigned long *mem_start, dt_push_token(4, mem_start, mem_end); dt_push_token(soff, mem_start, mem_end); valp = make_room(mem_start, mem_end, 4, 4); - *(u32 *)valp = node; + *(__be32 *)valp = cpu_to_be32(node); } } @@ -2380,16 +2417,16 @@ static void __init flatten_device_tree(void) dt_struct_end = PAGE_ALIGN(mem_start); /* Finish header */ - hdr->boot_cpuid_phys = prom.cpu; - hdr->magic = OF_DT_HEADER; - hdr->totalsize = dt_struct_end - dt_header_start; - hdr->off_dt_struct = dt_struct_start - dt_header_start; - hdr->off_dt_strings = dt_string_start - dt_header_start; - hdr->dt_strings_size = dt_string_end - dt_string_start; - hdr->off_mem_rsvmap = ((unsigned long)rsvmap) - dt_header_start; - hdr->version = OF_DT_VERSION; + hdr->boot_cpuid_phys = cpu_to_be32(prom.cpu); + hdr->magic = cpu_to_be32(OF_DT_HEADER); + hdr->totalsize = cpu_to_be32(dt_struct_end - dt_header_start); + hdr->off_dt_struct = cpu_to_be32(dt_struct_start - dt_header_start); + hdr->off_dt_strings = cpu_to_be32(dt_string_start - dt_header_start); + hdr->dt_strings_size = cpu_to_be32(dt_string_end - dt_string_start); + hdr->off_mem_rsvmap = cpu_to_be32(((unsigned long)rsvmap) - dt_header_start); + hdr->version = cpu_to_be32(OF_DT_VERSION); /* Version 16 is not backward compatible */ - hdr->last_comp_version = 0x10; + hdr->last_comp_version = cpu_to_be32(0x10); /* Copy the reserve map in */ memcpy(rsvmap, mem_reserve_map, sizeof(mem_reserve_map)); @@ -2400,8 +2437,8 @@ static void __init flatten_device_tree(void) prom_printf("reserved memory map:\n"); for (i = 0; i < mem_reserve_cnt; i++) prom_printf(" %x - %x\n", - mem_reserve_map[i].base, - mem_reserve_map[i].size); + be64_to_cpu(mem_reserve_map[i].base), + be64_to_cpu(mem_reserve_map[i].size)); } #endif /* Bump mem_reserve_cnt to cause further reservations to fail @@ -2413,7 +2450,6 @@ static void __init flatten_device_tree(void) dt_string_start, dt_string_end); prom_printf("Device tree struct 0x%x -> 0x%x\n", dt_struct_start, dt_struct_end); - } #ifdef CONFIG_PPC_MAPLE @@ -2746,18 +2782,19 @@ static void __init fixup_device_tree(void) static void __init prom_find_boot_cpu(void) { - u32 getprop_rval; + __be32 rval; ihandle prom_cpu; phandle cpu_pkg; - prom.cpu = 0; - if (prom_getprop(prom.chosen, "cpu", &prom_cpu, sizeof(prom_cpu)) <= 0) + rval = 0; + if (prom_getprop(prom.chosen, "cpu", &rval, sizeof(rval)) <= 0) return; + prom_cpu = be32_to_cpu(rval); cpu_pkg = call_prom("instance-to-package", 1, 1, prom_cpu); - prom_getprop(cpu_pkg, "reg", &getprop_rval, sizeof(getprop_rval)); - prom.cpu = getprop_rval; + prom_getprop(cpu_pkg, "reg", &rval, sizeof(rval)); + prom.cpu = be32_to_cpu(rval); prom_debug("Booting CPU hw index = %lu\n", prom.cpu); } @@ -2766,15 +2803,15 @@ static void __init prom_check_initrd(unsigned long r3, unsigned long r4) { #ifdef CONFIG_BLK_DEV_INITRD if (r3 && r4 && r4 != 0xdeadbeef) { - unsigned long val; + __be64 val; prom_initrd_start = is_kernel_addr(r3) ? __pa(r3) : r3; prom_initrd_end = prom_initrd_start + r4; - val = prom_initrd_start; + val = cpu_to_be64(prom_initrd_start); prom_setprop(prom.chosen, "/chosen", "linux,initrd-start", &val, sizeof(val)); - val = prom_initrd_end; + val = cpu_to_be64(prom_initrd_end); prom_setprop(prom.chosen, "/chosen", "linux,initrd-end", &val, sizeof(val)); @@ -2931,7 +2968,7 @@ unsigned long __init prom_init(unsigned long r3, unsigned long r4, */ prom_check_displays(); -#ifdef CONFIG_PPC64 +#if defined(CONFIG_PPC64) && defined(__BIG_ENDIAN__) /* * Initialize IOMMU (TCE tables) on pSeries. Do that before anything else * that uses the allocator, we need to make sure we get the top of memory @@ -2950,6 +2987,7 @@ unsigned long __init prom_init(unsigned long r3, unsigned long r4, prom_instantiate_rtas(); #ifdef CONFIG_PPC_POWERNV +#ifdef __BIG_ENDIAN__ /* Detect HAL and try instanciating it & doing takeover */ if (of_platform == PLATFORM_PSERIES_LPAR) { prom_query_opal(); @@ -2957,9 +2995,11 @@ unsigned long __init prom_init(unsigned long r3, unsigned long r4, prom_opal_hold_cpus(); prom_opal_takeover(); } - } else if (of_platform == PLATFORM_OPAL) + } else +#endif /* __BIG_ENDIAN__ */ + if (of_platform == PLATFORM_OPAL) prom_instantiate_opal(); -#endif +#endif /* CONFIG_PPC_POWERNV */ #ifdef CONFIG_PPC64 /* instantiate sml */ @@ -2978,10 +3018,11 @@ unsigned long __init prom_init(unsigned long r3, unsigned long r4, /* * Fill in some infos for use by the kernel later on */ - if (prom_memory_limit) + if (prom_memory_limit) { + __be64 val = cpu_to_be64(prom_memory_limit); prom_setprop(prom.chosen, "/chosen", "linux,memory-limit", - &prom_memory_limit, - sizeof(prom_memory_limit)); + &val, sizeof(val)); + } #ifdef CONFIG_PPC64 if (prom_iommu_off) prom_setprop(prom.chosen, "/chosen", "linux,iommu-off",