aboutsummaryrefslogtreecommitdiff
path: root/pc-bios
diff options
context:
space:
mode:
authorJanosch Frank <frankja@linux.ibm.com>2020-10-06 05:42:48 -0400
committerThomas Huth <thuth@redhat.com>2020-10-06 20:14:17 +0200
commit42ab98e7d71b834f4f8e2471f60b1c737b9543f3 (patch)
tree6c03757b45e9ba06a02fc1436ad93d00f922c239 /pc-bios
parent26e0b96fa9c303194fe159037d69d9ec30355d07 (diff)
pc-bios: s390x: Use reset PSW if avaliable
If a blob provides a reset PSW then we should use it instead of branching to the PSW address and using our own mask. Signed-off-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Message-Id: <20201006094249.50640-4-frankja@linux.ibm.com> [thuth: Use Elvis operator to shorten long line] Signed-off-by: Thomas Huth <thuth@redhat.com>
Diffstat (limited to 'pc-bios')
-rw-r--r--pc-bios/s390-ccw/bootmap.c6
-rw-r--r--pc-bios/s390-ccw/jump2ipl.c26
-rw-r--r--pc-bios/s390-ccw/s390-ccw.h1
3 files changed, 24 insertions, 9 deletions
diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c
index 73471801de..44df7d16af 100644
--- a/pc-bios/s390-ccw/bootmap.c
+++ b/pc-bios/s390-ccw/bootmap.c
@@ -273,7 +273,8 @@ static void run_eckd_boot_script(block_number_t bmt_block_nr,
IPL_assert(bms->entry[i].type == BOOT_SCRIPT_EXEC,
"Unknown script entry type");
- jump_to_IPL_code(bms->entry[i].address.load_address); /* no return */
+ write_reset_psw(bms->entry[i].address.load_address); /* no return */
+ jump_to_IPL_code(0); /* no return */
}
static void ipl_eckd_cdl(void)
@@ -527,7 +528,8 @@ static void zipl_run(ScsiBlockPtr *pte)
IPL_assert(entry->component_type == ZIPL_COMP_ENTRY_EXEC, "No EXEC entry");
/* should not return */
- jump_to_IPL_code(entry->compdat.load_psw & PSW_MASK_SHORT_ADDR);
+ write_reset_psw(entry->compdat.load_psw);
+ jump_to_IPL_code(0);
}
static void ipl_scsi(void)
diff --git a/pc-bios/s390-ccw/jump2ipl.c b/pc-bios/s390-ccw/jump2ipl.c
index b6aad32def..fbae45b03c 100644
--- a/pc-bios/s390-ccw/jump2ipl.c
+++ b/pc-bios/s390-ccw/jump2ipl.c
@@ -12,15 +12,21 @@
#define KERN_IMAGE_START 0x010000UL
#define RESET_PSW_MASK (PSW_MASK_SHORTPSW | PSW_MASK_64)
+#define RESET_PSW ((uint64_t)&jump_to_IPL_addr | RESET_PSW_MASK)
static uint64_t *reset_psw = 0, save_psw, ipl_continue;
+void write_reset_psw(uint64_t psw)
+{
+ *reset_psw = psw;
+}
+
static void jump_to_IPL_addr(void)
{
__attribute__((noreturn)) void (*ipl)(void) = (void *)ipl_continue;
/* Restore reset PSW */
- *reset_psw = save_psw;
+ write_reset_psw(save_psw);
ipl();
/* should not return */
@@ -43,11 +49,12 @@ void jump_to_IPL_code(uint64_t address)
* content of non-BIOS memory after we loaded the guest, so we
* save the original content and restore it in jump_to_IPL_2.
*/
- save_psw = *reset_psw;
- *reset_psw = (uint64_t) &jump_to_IPL_addr;
- *reset_psw |= RESET_PSW_MASK;
- ipl_continue = address;
- debug_print_int("set IPL addr to", ipl_continue);
+ if (address) {
+ save_psw = *reset_psw;
+ write_reset_psw(RESET_PSW);
+ ipl_continue = address;
+ }
+ debug_print_int("set IPL addr to", address ?: *reset_psw & PSW_MASK_SHORT_ADDR);
/* Ensure the guest output starts fresh */
sclp_print("\n");
@@ -77,7 +84,12 @@ void jump_to_low_kernel(void)
/* Trying to get PSW at zero address */
if (*((uint64_t *)0) & RESET_PSW_MASK) {
- jump_to_IPL_code((*((uint64_t *)0)) & PSW_MASK_SHORT_ADDR);
+ /*
+ * Surely nobody will try running directly from lowcore, so
+ * let's use 0 as an indication that we want to load the reset
+ * psw at 0x0 and not jump to the entry.
+ */
+ jump_to_IPL_code(0);
}
/* No other option left, so use the Linux kernel start address */
diff --git a/pc-bios/s390-ccw/s390-ccw.h b/pc-bios/s390-ccw/s390-ccw.h
index 9b86c120b4..6cd92669e9 100644
--- a/pc-bios/s390-ccw/s390-ccw.h
+++ b/pc-bios/s390-ccw/s390-ccw.h
@@ -76,6 +76,7 @@ int virtio_read(ulong sector, void *load_addr);
void zipl_load(void);
/* jump2ipl.c */
+void write_reset_psw(uint64_t psw);
void jump_to_IPL_code(uint64_t address);
void jump_to_low_kernel(void);