cregit-Linux how code gets into the kernel

Release 4.14 arch/s390/kernel/als.c

Directory: arch/s390/kernel
// SPDX-License-Identifier: GPL-2.0
/*
 *    Copyright IBM Corp. 2016
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <asm/processor.h>
#include <asm/facility.h>
#include <asm/lowcore.h>
#include <asm/sclp.h>
#include "entry.h"

/*
 * The code within this file will be called very early. It may _not_
 * access anything within the bss section, since that is not cleared
 * yet and may contain data (e.g. initrd) that must be saved by other
 * code.
 * For temporary objects the stack (16k) should be used.
 */


static unsigned long als[] __initdata = { FACILITIES_ALS };


static void __init u16_to_hex(char *str, u16 val) { int i, num; for (i = 1; i <= 4; i++) { num = (val >> (16 - 4 * i)) & 0xf; if (num >= 10) num += 7; *str++ = '0' + num; } *str = '\0'; }

Contributors

PersonTokensPropCommitsCommitProp
Heiko Carstens73100.00%1100.00%
Total73100.00%1100.00%


static void __init print_machine_type(void) { static char mach_str[80] __initdata = "Detected machine-type number: "; char type_str[5]; struct cpuid id; get_cpu_id(&id); u16_to_hex(type_str, id.machine); strcat(mach_str, type_str); strcat(mach_str, "\n"); sclp_early_printk(mach_str); }

Contributors

PersonTokensPropCommitsCommitProp
Heiko Carstens63100.00%3100.00%
Total63100.00%3100.00%


static void __init u16_to_decimal(char *str, u16 val) { int div = 1; while (div * 10 <= val) div *= 10; while (div) { *str++ = '0' + val / div; val %= div; div /= 10; } *str = '\0'; }

Contributors

PersonTokensPropCommitsCommitProp
Heiko Carstens60100.00%1100.00%
Total60100.00%1100.00%


static void __init print_missing_facilities(void) { static char als_str[80] __initdata = "Missing facilities: "; unsigned long val; char val_str[6]; int i, j, first; first = 1; for (i = 0; i < ARRAY_SIZE(als); i++) { val = ~S390_lowcore.stfle_fac_list[i] & als[i]; for (j = 0; j < BITS_PER_LONG; j++) { if (!(val & (1UL << (BITS_PER_LONG - 1 - j)))) continue; if (!first) strcat(als_str, ","); /* * Make sure we stay within one line. Consider that * each facility bit adds up to five characters and * z/VM adds a four character prefix. */ if (strlen(als_str) > 70) { strcat(als_str, "\n"); sclp_early_printk(als_str); *als_str = '\0'; } u16_to_decimal(val_str, i * BITS_PER_LONG + j); strcat(als_str, val_str); first = 0; } } strcat(als_str, "\n"); sclp_early_printk(als_str); sclp_early_printk("See Principles of Operations for facility bits\n"); }

Contributors

PersonTokensPropCommitsCommitProp
Heiko Carstens188100.00%3100.00%
Total188100.00%3100.00%


static void __init facility_mismatch(void) { sclp_early_printk("The Linux kernel requires more recent processor hardware\n"); print_machine_type(); print_missing_facilities(); disabled_wait(0x8badcccc); }

Contributors

PersonTokensPropCommitsCommitProp
Heiko Carstens25100.00%4100.00%
Total25100.00%4100.00%


void __init verify_facilities(void) { int i; for (i = 0; i < ARRAY_SIZE(S390_lowcore.stfle_fac_list); i++) S390_lowcore.stfle_fac_list[i] = 0; asm volatile( " stfl 0(0)\n" : "=m" (S390_lowcore.stfl_fac_list)); S390_lowcore.stfle_fac_list[0] = (u64)S390_lowcore.stfl_fac_list << 32; if (S390_lowcore.stfl_fac_list & 0x01000000) { register unsigned long reg0 asm("0") = ARRAY_SIZE(als) - 1; asm volatile(".insn s,0xb2b00000,0(%1)" /* stfle */ : "+d" (reg0) : "a" (&S390_lowcore.stfle_fac_list) : "memory", "cc"); } for (i = 0; i < ARRAY_SIZE(als); i++) { if ((S390_lowcore.stfle_fac_list[i] & als[i]) != als[i]) facility_mismatch(); } }

Contributors

PersonTokensPropCommitsCommitProp
Heiko Carstens130100.00%2100.00%
Total130100.00%2100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Heiko Carstens57399.83%583.33%
Greg Kroah-Hartman10.17%116.67%
Total574100.00%6100.00%
Directory: arch/s390/kernel
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.