diff options
Diffstat (limited to 'arch/arc/kernel/setup.c')
| -rw-r--r-- | arch/arc/kernel/setup.c | 699 |
1 files changed, 699 insertions, 0 deletions
diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c new file mode 100644 index 000000000..c10994dae --- /dev/null +++ b/arch/arc/kernel/setup.c @@ -0,0 +1,699 @@ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/seq_file.h> +#include <linux/fs.h> +#include <linux/delay.h> +#include <linux/root_dev.h> +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/clocksource.h> +#include <linux/console.h> +#include <linux/module.h> +#include <linux/sizes.h> +#include <linux/cpu.h> +#include <linux/of_fdt.h> +#include <linux/of.h> +#include <linux/cache.h> +#include <asm/sections.h> +#include <asm/arcregs.h> +#include <asm/tlb.h> +#include <asm/setup.h> +#include <asm/page.h> +#include <asm/irq.h> +#include <asm/unwind.h> +#include <asm/mach_desc.h> +#include <asm/smp.h> + +#define FIX_PTR(x) __asm__ __volatile__(";" : "+r"(x)) + +unsigned int intr_to_DE_cnt; + +/* Part of U-boot ABI: see head.S */ +int __initdata uboot_tag; +int __initdata uboot_magic; +char __initdata *uboot_arg; + +const struct machine_desc *machine_desc; + +struct task_struct *_current_task[NR_CPUS]; /* For stack switching */ + +struct cpuinfo_arc cpuinfo_arc700[NR_CPUS]; + +static const struct id_to_str arc_cpu_rel[] = { +#ifdef CONFIG_ISA_ARCOMPACT + { 0x34, "R4.10"}, + { 0x35, "R4.11"}, +#else + { 0x51, "R2.0" }, + { 0x52, "R2.1" }, + { 0x53, "R3.0" }, + { 0x54, "R3.10a" }, +#endif + { 0x00, NULL } +}; + +static const struct id_to_str arc_cpu_nm[] = { +#ifdef CONFIG_ISA_ARCOMPACT + { 0x20, "ARC 600" }, + { 0x30, "ARC 770" }, /* 750 identified seperately */ +#else + { 0x40, "ARC EM" }, + { 0x50, "ARC HS38" }, + { 0x54, "ARC HS48" }, +#endif + { 0x00, "Unknown" } +}; + +static void read_decode_ccm_bcr(struct cpuinfo_arc *cpu) +{ + if (is_isa_arcompact()) { + struct bcr_iccm_arcompact iccm; + struct bcr_dccm_arcompact dccm; + + READ_BCR(ARC_REG_ICCM_BUILD, iccm); + if (iccm.ver) { + cpu->iccm.sz = 4096 << iccm.sz; /* 8K to 512K */ + cpu->iccm.base_addr = iccm.base << 16; + } + + READ_BCR(ARC_REG_DCCM_BUILD, dccm); + if (dccm.ver) { + unsigned long base; + cpu->dccm.sz = 2048 << dccm.sz; /* 2K to 256K */ + + base = read_aux_reg(ARC_REG_DCCM_BASE_BUILD); + cpu->dccm.base_addr = base & ~0xF; + } + } else { + struct bcr_iccm_arcv2 iccm; + struct bcr_dccm_arcv2 dccm; + unsigned long region; + + READ_BCR(ARC_REG_ICCM_BUILD, iccm); + if (iccm.ver) { + cpu->iccm.sz = 256 << iccm.sz00; /* 512B to 16M */ + if (iccm.sz00 == 0xF && iccm.sz01 > 0) + cpu->iccm.sz <<= iccm.sz01; + + region = read_aux_reg(ARC_REG_AUX_ICCM); + cpu->iccm.base_addr = region & 0xF0000000; + } + + READ_BCR(ARC_REG_DCCM_BUILD, dccm); + if (dccm.ver) { + cpu->dccm.sz = 256 << dccm.sz0; + if (dccm.sz0 == 0xF && dccm.sz1 > 0) + cpu->dccm.sz <<= dccm.sz1; + + region = read_aux_reg(ARC_REG_AUX_DCCM); + cpu->dccm.base_addr = region & 0xF0000000; + } + } +} + +static void read_arc_build_cfg_regs(void) +{ + struct bcr_timer timer; + struct bcr_generic bcr; + struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()]; + const struct id_to_str *tbl; + struct bcr_isa_arcv2 isa; + + FIX_PTR(cpu); + + READ_BCR(AUX_IDENTITY, cpu->core); + + for (tbl = &arc_cpu_rel[0]; tbl->id != 0; tbl++) { + if (cpu->core.family == tbl->id) { + cpu->details = tbl->str; + break; + } + } + + for (tbl = &arc_cpu_nm[0]; tbl->id != 0; tbl++) { + if ((cpu->core.family & 0xF4) == tbl->id) + break; + } + cpu->name = tbl->str; + + READ_BCR(ARC_REG_TIMERS_BCR, timer); + cpu->extn.timer0 = timer.t0; + cpu->extn.timer1 = timer.t1; + cpu->extn.rtc = timer.rtc; + + cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE); + + READ_BCR(ARC_REG_MUL_BCR, cpu->extn_mpy); + + cpu->extn.norm = read_aux_reg(ARC_REG_NORM_BCR) > 1 ? 1 : 0; /* 2,3 */ + cpu->extn.barrel = read_aux_reg(ARC_REG_BARREL_BCR) > 1 ? 1 : 0; /* 2,3 */ + cpu->extn.swap = read_aux_reg(ARC_REG_SWAP_BCR) ? 1 : 0; /* 1,3 */ + cpu->extn.crc = read_aux_reg(ARC_REG_CRC_BCR) ? 1 : 0; + cpu->extn.minmax = read_aux_reg(ARC_REG_MIXMAX_BCR) > 1 ? 1 : 0; /* 2 */ + cpu->extn.swape = (cpu->core.family >= 0x34) ? 1 : + IS_ENABLED(CONFIG_ARC_HAS_SWAPE); + + READ_BCR(ARC_REG_XY_MEM_BCR, cpu->extn_xymem); + + /* Read CCM BCRs for boot reporting even if not enabled in Kconfig */ + read_decode_ccm_bcr(cpu); + + read_decode_mmu_bcr(); + read_decode_cache_bcr(); + + if (is_isa_arcompact()) { + struct bcr_fp_arcompact sp, dp; + struct bcr_bpu_arcompact bpu; + + READ_BCR(ARC_REG_FP_BCR, sp); + READ_BCR(ARC_REG_DPFP_BCR, dp); + cpu->extn.fpu_sp = sp.ver ? 1 : 0; + cpu->extn.fpu_dp = dp.ver ? 1 : 0; + + READ_BCR(ARC_REG_BPU_BCR, bpu); + cpu->bpu.ver = bpu.ver; + cpu->bpu.full = bpu.fam ? 1 : 0; + if (bpu.ent) { + cpu->bpu.num_cache = 256 << (bpu.ent - 1); + cpu->bpu.num_pred = 256 << (bpu.ent - 1); + } + } else { + struct bcr_fp_arcv2 spdp; + struct bcr_bpu_arcv2 bpu; + + READ_BCR(ARC_REG_FP_V2_BCR, spdp); + cpu->extn.fpu_sp = spdp.sp ? 1 : 0; + cpu->extn.fpu_dp = spdp.dp ? 1 : 0; + + READ_BCR(ARC_REG_BPU_BCR, bpu); + cpu->bpu.ver = bpu.ver; + cpu->bpu.full = bpu.ft; + cpu->bpu.num_cache = 256 << bpu.bce; + cpu->bpu.num_pred = 2048 << bpu.pte; + + if (cpu->core.family >= 0x54) { + + struct bcr_uarch_build_arcv2 uarch; + + /* + * The first 0x54 core (uarch maj:min 0:1 or 0:2) was + * dual issue only (HS4x). But next uarch rev (1:0) + * allows it be configured for single issue (HS3x) + * Ensure we fiddle with dual issue only on HS4x + */ + READ_BCR(ARC_REG_MICRO_ARCH_BCR, uarch); + + if (uarch.prod == 4) { + unsigned int exec_ctrl; + + /* dual issue hardware always present */ + cpu->extn.dual = 1; + + READ_BCR(AUX_EXEC_CTRL, exec_ctrl); + + /* dual issue hardware enabled ? */ + cpu->extn.dual_enb = !(exec_ctrl & 1); + + } + } + } + + READ_BCR(ARC_REG_AP_BCR, bcr); + cpu->extn.ap = bcr.ver ? 1 : 0; + + READ_BCR(ARC_REG_SMART_BCR, bcr); + cpu->extn.smart = bcr.ver ? 1 : 0; + + READ_BCR(ARC_REG_RTT_BCR, bcr); + cpu->extn.rtt = bcr.ver ? 1 : 0; + + cpu->extn.debug = cpu->extn.ap | cpu->extn.smart | cpu->extn.rtt; + + READ_BCR(ARC_REG_ISA_CFG_BCR, isa); + + /* some hacks for lack of feature BCR info in old ARC700 cores */ + if (is_isa_arcompact()) { + if (!isa.ver) /* ISA BCR absent, use Kconfig info */ + cpu->isa.atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC); + else { + /* ARC700_BUILD only has 2 bits of isa info */ + struct bcr_generic bcr = *(struct bcr_generic *)&isa; + cpu->isa.atomic = bcr.info & 1; + } + + cpu->isa.be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN); + + /* there's no direct way to distinguish 750 vs. 770 */ + if (unlikely(cpu->core.family < 0x34 || cpu->mmu.ver < 3)) + cpu->name = "ARC750"; + } else { + cpu->isa = isa; + } +} + +static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len) +{ + struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id]; + struct bcr_identity *core = &cpu->core; + int i, n = 0; + + FIX_PTR(cpu); + + n += scnprintf(buf + n, len - n, + "\nIDENTITY\t: ARCVER [%#02x] ARCNUM [%#02x] CHIPID [%#4x]\n", + core->family, core->cpu_id, core->chip_id); + + n += scnprintf(buf + n, len - n, "processor [%d]\t: %s %s (%s ISA) %s%s%s\n", + cpu_id, cpu->name, cpu->details, + is_isa_arcompact() ? "ARCompact" : "ARCv2", + IS_AVAIL1(cpu->isa.be, "[Big-Endian]"), + IS_AVAIL3(cpu->extn.dual, cpu->extn.dual_enb, " Dual-Issue ")); + + n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s%s%s\nISA Extn\t: ", + IS_AVAIL1(cpu->extn.timer0, "Timer0 "), + IS_AVAIL1(cpu->extn.timer1, "Timer1 "), + IS_AVAIL2(cpu->extn.rtc, "RTC [UP 64-bit] ", CONFIG_ARC_TIMERS_64BIT), + IS_AVAIL2(cpu->extn.gfrc, "GFRC [SMP 64-bit] ", CONFIG_ARC_TIMERS_64BIT)); + + n += i = scnprintf(buf + n, len - n, "%s%s%s%s%s", + IS_AVAIL2(cpu->isa.atomic, "atomic ", CONFIG_ARC_HAS_LLSC), + IS_AVAIL2(cpu->isa.ldd, "ll64 ", CONFIG_ARC_HAS_LL64), + IS_AVAIL1(cpu->isa.unalign, "unalign (not used)")); + + if (i) + n += scnprintf(buf + n, len - n, "\n\t\t: "); + + if (cpu->extn_mpy.ver) { + if (cpu->extn_mpy.ver <= 0x2) { /* ARCompact */ + n += scnprintf(buf + n, len - n, "mpy "); + } else { + int opt = 2; /* stock MPY/MPYH */ + + if (cpu->extn_mpy.dsp) /* OPT 7-9 */ + opt = cpu->extn_mpy.dsp + 6; + + n += scnprintf(buf + n, len - n, "mpy[opt %d] ", opt); + } + } + + n += scnprintf(buf + n, len - n, "%s%s%s%s%s%s%s%s\n", + IS_AVAIL1(cpu->isa.div_rem, "div_rem "), + IS_AVAIL1(cpu->extn.norm, "norm "), + IS_AVAIL1(cpu->extn.barrel, "barrel-shift "), + IS_AVAIL1(cpu->extn.swap, "swap "), + IS_AVAIL1(cpu->extn.minmax, "minmax "), + IS_AVAIL1(cpu->extn.crc, "crc "), + IS_AVAIL2(cpu->extn.swape, "swape", CONFIG_ARC_HAS_SWAPE)); + + if (cpu->bpu.ver) + n += scnprintf(buf + n, len - n, + "BPU\t\t: %s%s match, cache:%d, Predict Table:%d", + IS_AVAIL1(cpu->bpu.full, "full"), + IS_AVAIL1(!cpu->bpu.full, "partial"), + cpu->bpu.num_cache, cpu->bpu.num_pred); + + if (is_isa_arcv2()) { + struct bcr_lpb lpb; + + READ_BCR(ARC_REG_LPB_BUILD, lpb); + if (lpb.ver) { + unsigned int ctl; + ctl = read_aux_reg(ARC_REG_LPB_CTRL); + + n += scnprintf(buf + n, len - n, " Loop Buffer:%d %s", + lpb.entries, + IS_DISABLED_RUN(!ctl)); + } + } + + n += scnprintf(buf + n, len - n, "\n"); + return buf; +} + +static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len) +{ + int n = 0; + struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id]; + + FIX_PTR(cpu); + + n += scnprintf(buf + n, len - n, "Vector Table\t: %#x\n", cpu->vec_base); + + if (cpu->extn.fpu_sp || cpu->extn.fpu_dp) + n += scnprintf(buf + n, len - n, "FPU\t\t: %s%s\n", + IS_AVAIL1(cpu->extn.fpu_sp, "SP "), + IS_AVAIL1(cpu->extn.fpu_dp, "DP ")); + + if (cpu->extn.debug) + n += scnprintf(buf + n, len - n, "DEBUG\t\t: %s%s%s\n", + IS_AVAIL1(cpu->extn.ap, "ActionPoint "), + IS_AVAIL1(cpu->extn.smart, "smaRT "), + IS_AVAIL1(cpu->extn.rtt, "RTT ")); + + if (cpu->dccm.sz || cpu->iccm.sz) + n += scnprintf(buf + n, len - n, "Extn [CCM]\t: DCCM @ %x, %d KB / ICCM: @ %x, %d KB\n", + cpu->dccm.base_addr, TO_KB(cpu->dccm.sz), + cpu->iccm.base_addr, TO_KB(cpu->iccm.sz)); + + if (is_isa_arcv2()) { + + /* Error Protection: ECC/Parity */ + struct bcr_erp erp; + READ_BCR(ARC_REG_ERP_BUILD, erp); + + if (erp.ver) { + struct ctl_erp ctl; + READ_BCR(ARC_REG_ERP_CTRL, ctl); + + /* inverted bits: 0 means enabled */ + n += scnprintf(buf + n, len - n, "Extn [ECC]\t: %s%s%s%s%s%s\n", + IS_AVAIL3(erp.ic, !ctl.dpi, "IC "), + IS_AVAIL3(erp.dc, !ctl.dpd, "DC "), + IS_AVAIL3(erp.mmu, !ctl.mpd, "MMU ")); + } + } + + n += scnprintf(buf + n, len - n, "OS ABI [v%d]\t: %s\n", + EF_ARC_OSABI_CURRENT >> 8, + EF_ARC_OSABI_CURRENT == EF_ARC_OSABI_V3 ? + "no-legacy-syscalls" : "64-bit data any register aligned"); + + return buf; +} + +static void arc_chk_core_config(void) +{ + struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()]; + int saved = 0, present = 0; + char *opt_nm = NULL; + + if (!cpu->extn.timer0) + panic("Timer0 is not present!\n"); + + if (!cpu->extn.timer1) + panic("Timer1 is not present!\n"); + +#ifdef CONFIG_ARC_HAS_DCCM + /* + * DCCM can be arbit placed in hardware. + * Make sure it's placement/sz matches what Linux is built with + */ + if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr) + panic("Linux built with incorrect DCCM Base address\n"); + + if (CONFIG_ARC_DCCM_SZ * SZ_1K != cpu->dccm.sz) + panic("Linux built with incorrect DCCM Size\n"); +#endif + +#ifdef CONFIG_ARC_HAS_ICCM + if (CONFIG_ARC_ICCM_SZ * SZ_1K != cpu->iccm.sz) + panic("Linux built with incorrect ICCM Size\n"); +#endif + + /* + * FP hardware/software config sanity + * -If hardware present, kernel needs to save/restore FPU state + * -If not, it will crash trying to save/restore the non-existant regs + */ + + if (is_isa_arcompact()) { + opt_nm = "CONFIG_ARC_FPU_SAVE_RESTORE"; + saved = IS_ENABLED(CONFIG_ARC_FPU_SAVE_RESTORE); + + /* only DPDP checked since SP has no arch visible regs */ + present = cpu->extn.fpu_dp; + } else { + opt_nm = "CONFIG_ARC_HAS_ACCL_REGS"; + saved = IS_ENABLED(CONFIG_ARC_HAS_ACCL_REGS); + + /* Accumulator Low:High pair (r58:59) present if DSP MPY or FPU */ + present = cpu->extn_mpy.dsp | cpu->extn.fpu_sp | cpu->extn.fpu_dp; + } + + if (present && !saved) + pr_warn("Enable %s for working apps\n", opt_nm); + else if (!present && saved) + panic("Disable %s, hardware NOT present\n", opt_nm); +} + +/* + * Initialize and setup the processor core + * This is called by all the CPUs thus should not do special case stuff + * such as only for boot CPU etc + */ + +void setup_processor(void) +{ + char str[512]; + int cpu_id = smp_processor_id(); + + read_arc_build_cfg_regs(); + arc_init_IRQ(); + + pr_info("%s", arc_cpu_mumbojumbo(cpu_id, str, sizeof(str))); + + arc_mmu_init(); + arc_cache_init(); + + pr_info("%s", arc_extn_mumbojumbo(cpu_id, str, sizeof(str))); + pr_info("%s", arc_platform_smp_cpuinfo()); + + arc_chk_core_config(); +} + +static inline bool uboot_arg_invalid(unsigned long addr) +{ + /* + * Check that it is a untranslated address (although MMU is not enabled + * yet, it being a high address ensures this is not by fluke) + */ + if (addr < PAGE_OFFSET) + return true; + + /* Check that address doesn't clobber resident kernel image */ + return addr >= (unsigned long)_stext && addr <= (unsigned long)_end; +} + +#define IGNORE_ARGS "Ignore U-boot args: " + +/* uboot_tag values for U-boot - kernel ABI revision 0; see head.S */ +#define UBOOT_TAG_NONE 0 +#define UBOOT_TAG_CMDLINE 1 +#define UBOOT_TAG_DTB 2 +/* We always pass 0 as magic from U-boot */ +#define UBOOT_MAGIC_VALUE 0 + +void __init handle_uboot_args(void) +{ + bool use_embedded_dtb = true; + bool append_cmdline = false; + + /* check that we know this tag */ + if (uboot_tag != UBOOT_TAG_NONE && + uboot_tag != UBOOT_TAG_CMDLINE && + uboot_tag != UBOOT_TAG_DTB) { + pr_warn(IGNORE_ARGS "invalid uboot tag: '%08x'\n", uboot_tag); + goto ignore_uboot_args; + } + + if (uboot_magic != UBOOT_MAGIC_VALUE) { + pr_warn(IGNORE_ARGS "non zero uboot magic\n"); + goto ignore_uboot_args; + } + + if (uboot_tag != UBOOT_TAG_NONE && + uboot_arg_invalid((unsigned long)uboot_arg)) { + pr_warn(IGNORE_ARGS "invalid uboot arg: '%px'\n", uboot_arg); + goto ignore_uboot_args; + } + + /* see if U-boot passed an external Device Tree blob */ + if (uboot_tag == UBOOT_TAG_DTB) { + machine_desc = setup_machine_fdt((void *)uboot_arg); + + /* external Device Tree blob is invalid - use embedded one */ + use_embedded_dtb = !machine_desc; + } + + if (uboot_tag == UBOOT_TAG_CMDLINE) + append_cmdline = true; + +ignore_uboot_args: + + if (use_embedded_dtb) { + machine_desc = setup_machine_fdt(__dtb_start); + if (!machine_desc) + panic("Embedded DT invalid\n"); + } + + /* + * NOTE: @boot_command_line is populated by setup_machine_fdt() so this + * append processing can only happen after. + */ + if (append_cmdline) { + /* Ensure a whitespace between the 2 cmdlines */ + strlcat(boot_command_line, " ", COMMAND_LINE_SIZE); + strlcat(boot_command_line, uboot_arg, COMMAND_LINE_SIZE); + } +} + +void __init setup_arch(char **cmdline_p) +{ + handle_uboot_args(); + + /* Save unparsed command line copy for /proc/cmdline */ + *cmdline_p = boot_command_line; + + /* To force early parsing of things like mem=xxx */ + parse_early_param(); + + /* Platform/board specific: e.g. early console registration */ + if (machine_desc->init_early) + machine_desc->init_early(); + + smp_init_cpus(); + + setup_processor(); + setup_arch_memory(); + + /* copy flat DT out of .init and then unflatten it */ + unflatten_and_copy_device_tree(); + + /* Can be issue if someone passes cmd line arg "ro" + * But that is unlikely so keeping it as it is + */ + root_mountflags &= ~MS_RDONLY; + +#if defined(CONFIG_VT) && defined(CONFIG_DUMMY_CONSOLE) + conswitchp = &dummy_con; +#endif + + arc_unwind_init(); +} + +/* + * Called from start_kernel() - boot CPU only + */ +void __init time_init(void) +{ + of_clk_init(NULL); + timer_probe(); +} + +static int __init customize_machine(void) +{ + if (machine_desc->init_machine) + machine_desc->init_machine(); + + return 0; +} +arch_initcall(customize_machine); + +static int __init init_late_machine(void) +{ + if (machine_desc->init_late) + machine_desc->init_late(); + + return 0; +} +late_initcall(init_late_machine); +/* + * Get CPU information for use by the procfs. + */ + +#define cpu_to_ptr(c) ((void *)(0xFFFF0000 | (unsigned int)(c))) +#define ptr_to_cpu(p) (~0xFFFF0000UL & (unsigned int)(p)) + +static int show_cpuinfo(struct seq_file *m, void *v) +{ + char *str; + int cpu_id = ptr_to_cpu(v); + struct device *cpu_dev = get_cpu_device(cpu_id); + struct clk *cpu_clk; + unsigned long freq = 0; + + if (!cpu_online(cpu_id)) { + seq_printf(m, "processor [%d]\t: Offline\n", cpu_id); + goto done; + } + + str = (char *)__get_free_page(GFP_KERNEL); + if (!str) + goto done; + + seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE)); + + cpu_clk = clk_get(cpu_dev, NULL); + if (IS_ERR(cpu_clk)) { + seq_printf(m, "CPU speed \t: Cannot get clock for processor [%d]\n", + cpu_id); + } else { + freq = clk_get_rate(cpu_clk); + } + if (freq) + seq_printf(m, "CPU speed\t: %lu.%02lu Mhz\n", + freq / 1000000, (freq / 10000) % 100); + + seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n", + loops_per_jiffy / (500000 / HZ), + (loops_per_jiffy / (5000 / HZ)) % 100); + + seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE)); + seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE)); + seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE)); + seq_printf(m, arc_platform_smp_cpuinfo()); + + free_page((unsigned long)str); +done: + seq_printf(m, "\n"); + + return 0; +} + +static void *c_start(struct seq_file *m, loff_t *pos) +{ + /* + * Callback returns cpu-id to iterator for show routine, NULL to stop. + * However since NULL is also a valid cpu-id (0), we use a round-about + * way to pass it w/o having to kmalloc/free a 2 byte string. + * Encode cpu-id as 0xFFcccc, which is decoded by show routine. + */ + return *pos < nr_cpu_ids ? cpu_to_ptr(*pos) : NULL; +} + +static void *c_next(struct seq_file *m, void *v, loff_t *pos) +{ + ++*pos; + return c_start(m, pos); +} + +static void c_stop(struct seq_file *m, void *v) +{ +} + +const struct seq_operations cpuinfo_op = { + .start = c_start, + .next = c_next, + .stop = c_stop, + .show = show_cpuinfo +}; + +static DEFINE_PER_CPU(struct cpu, cpu_topology); + +static int __init topology_init(void) +{ + int cpu; + + for_each_present_cpu(cpu) + register_cpu(&per_cpu(cpu_topology, cpu), cpu); + + return 0; +} + +subsys_initcall(topology_init); |