From bd50b7436217b4123911c2bca1efd74718654f06 Mon Sep 17 00:00:00 2001
From: Alexander Gordeev <agordeev@linux.ibm.com>
Date: Sun, 4 Dec 2022 21:15:41 +0100
Subject: [PATCH] s390/boot: detect and enable memory facilities
Detect and enable memory facilities which is a
prerequisite for pgtables setup in the decompressor.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
---
arch/s390/boot/boot.h | 8 ++++++++
arch/s390/boot/startup.c | 18 ++++++++++++++++++
2 files changed, 26 insertions(+)
diff --git a/arch/s390/boot/boot.h b/arch/s390/boot/boot.h
index f6e82cf7851e2..286441cf3bf02 100644
--- a/arch/s390/boot/boot.h
+++ b/arch/s390/boot/boot.h
@@ -8,6 +8,12 @@
#ifndef __ASSEMBLY__
+struct machine_info {
+ unsigned char has_edat1 : 1;
+ unsigned char has_edat2 : 1;
+ unsigned char has_nx : 1;
+};
+
struct vmlinux_info {
unsigned long default_lma;
void (*entry)(void);
@@ -38,6 +44,8 @@ unsigned long get_random_base(unsigned long safe_addr);
void __printf(1, 2) decompressor_printk(const char *fmt, ...);
void error(char *m);
+extern struct machine_info machine;
+
/* Symbols defined by linker scripts */
extern const char kernel_version[];
extern unsigned long memory_limit;
diff --git a/arch/s390/boot/startup.c b/arch/s390/boot/startup.c
index 47ca3264c0230..da6ee587fe9ac 100644
--- a/arch/s390/boot/startup.c
+++ b/arch/s390/boot/startup.c
@@ -33,6 +33,8 @@ u64 __bootdata_preserved(stfle_fac_list[16]);
u64 __bootdata_preserved(alt_stfle_fac_list[16]);
struct oldmem_data __bootdata_preserved(oldmem_data);
+struct machine_info machine;
+
void error(char *x)
{
sclp_early_printk("\n\n");
@@ -42,6 +44,20 @@ void error(char *x)
disabled_wait();
}
+static void detect_facilities(void)
+{
+ if (test_facility(8)) {
+ machine.has_edat1 = 1;
+ __ctl_set_bit(0, 23);
+ }
+ if (test_facility(78))
+ machine.has_edat2 = 1;
+ if (!noexec_disabled && test_facility(130)) {
+ machine.has_nx = 1;
+ __ctl_set_bit(0, 20);
+ }
+}
+
static void setup_lpp(void)
{
S390_lowcore.current_pid = 0;
@@ -254,6 +270,8 @@ void startup_kernel(void)
unsigned long safe_addr;
void *img;
+ detect_facilities();
+
initrd_data.start = parmarea.initrd_start;
initrd_data.size = parmarea.initrd_size;
oldmem_data.start = parmarea.oldmem_base;
--
GitLab