mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-14 13:46:50 +07:00
d5ab7a34f9
This patch - unifies the old sclp early code and the sclp early printk code, so they can use common functions - makes sure all sclp early functions and variables have the same "sclp_early" prefix - converts the sclp early printk code into readable code by using existing data structures instead of hard coded magic arrays - splits the early sclp code into two files: sclp_early.c and sclp_early_core.c. The core file contains everything that is required by the kernel decompressor and may not call functions not contained within the core file. Otherwise the result would be a link error. - changes interrupt handling to be completely synchronous. The old early sclp code had a small window which allowed to receive several interrupts instead of exactly the single expected interrupt. This did hide a subtle potential bug, which is fixed with this large rework. - contains a couple of small cleanups. Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
125 lines
2.9 KiB
C
125 lines
2.9 KiB
C
/*
|
|
* 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';
|
|
}
|
|
|
|
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);
|
|
sclp_early_printk(mach_str);
|
|
}
|
|
|
|
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';
|
|
}
|
|
|
|
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) {
|
|
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;
|
|
}
|
|
}
|
|
sclp_early_printk(als_str);
|
|
sclp_early_printk("See Principles of Operations for facility bits");
|
|
}
|
|
|
|
static void __init facility_mismatch(void)
|
|
{
|
|
sclp_early_printk("The Linux kernel requires more recent processor hardware");
|
|
print_machine_type();
|
|
print_missing_facilities();
|
|
disabled_wait(0x8badcccc);
|
|
}
|
|
|
|
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();
|
|
}
|
|
}
|