1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright IBM Corp. 2016
4 */
5 #include <linux/kernel.h>
6 #include <asm/processor.h>
7 #include <asm/facility.h>
8 #include <asm/lowcore.h>
9 #include <asm/sclp.h>
10 #include "boot.h"
11
12 static unsigned long als[] = { FACILITIES_ALS };
13
u16_to_decimal(char * str,u16 val)14 static void u16_to_decimal(char *str, u16 val)
15 {
16 int div = 1;
17
18 while (div * 10 <= val)
19 div *= 10;
20 while (div) {
21 *str++ = '0' + val / div;
22 val %= div;
23 div /= 10;
24 }
25 *str = '\0';
26 }
27
print_missing_facilities(void)28 void print_missing_facilities(void)
29 {
30 static char als_str[80] = "Missing facilities: ";
31 unsigned long val;
32 char val_str[6];
33 int i, j, first;
34
35 first = 1;
36 for (i = 0; i < ARRAY_SIZE(als); i++) {
37 val = ~stfle_fac_list[i] & als[i];
38 for (j = 0; j < BITS_PER_LONG; j++) {
39 if (!(val & (1UL << (BITS_PER_LONG - 1 - j))))
40 continue;
41 if (!first)
42 strcat(als_str, ",");
43 /*
44 * Make sure we stay within one line. Consider that
45 * each facility bit adds up to five characters and
46 * z/VM adds a four character prefix.
47 */
48 if (strlen(als_str) > 70) {
49 boot_printk("%s\n", als_str);
50 *als_str = '\0';
51 }
52 u16_to_decimal(val_str, i * BITS_PER_LONG + j);
53 strcat(als_str, val_str);
54 first = 0;
55 }
56 }
57 boot_printk("%s\n", als_str);
58 }
59
facility_mismatch(void)60 static void facility_mismatch(void)
61 {
62 struct cpuid id;
63
64 get_cpu_id(&id);
65 boot_printk("The Linux kernel requires more recent processor hardware\n");
66 boot_printk("Detected machine-type number: %4x\n", id.machine);
67 print_missing_facilities();
68 boot_printk("See Principles of Operations for facility bits\n");
69 disabled_wait();
70 }
71
verify_facilities(void)72 void verify_facilities(void)
73 {
74 int i;
75
76 __stfle(stfle_fac_list, ARRAY_SIZE(stfle_fac_list));
77 for (i = 0; i < ARRAY_SIZE(als); i++) {
78 if ((stfle_fac_list[i] & als[i]) != als[i])
79 facility_mismatch();
80 }
81 }
82