@@ -515,6 +515,7 @@ static void zipl_run(ScsiBlockPtr *pte)
IPL_assert(entry->component_type == ZIPL_COMP_ENTRY_EXEC, "No EXEC entry");
/* should not return */
+ write_reset_psw(entry->compdat.load_psw);
jump_to_IPL_code(entry->compdat.load_psw & PSW_MASK_SHORT_ADDR);
}
@@ -13,20 +13,28 @@
#define KERN_IMAGE_START 0x010000UL
#define RESET_PSW_MASK (PSW_MASK_SHORTPSW | PSW_MASK_64)
-typedef struct ResetInfo {
- uint64_t ipl_psw;
- uint32_t ipl_continue;
-} ResetInfo;
-
-static ResetInfo save;
+uint64_t *reset_psw = 0, save_psw, ipl_continue;
static void jump_to_IPL_2(void)
{
- ResetInfo *current = 0;
+ /* Restore reset PSW and io and external new PSWs */
+ *reset_psw = save_psw;
- void (*ipl)(void) = (void *) (uint64_t) current->ipl_continue;
- *current = save;
- ipl(); /* should not return */
+ /* No reset PSW, let's jump instead. */
+ if (ipl_continue) {
+ void (*ipl)(void) = (void *) (uint64_t) ipl_continue;
+ ipl();
+ }
+
+ /* Reset PSW available, let's load it */
+ asm volatile ("lpsw 0(%0)\n"
+ : : "a" (0):);
+ /* should not return */
+}
+
+void write_reset_psw(uint64_t psw)
+{
+ *reset_psw = psw;
}
void jump_to_IPL_code(uint64_t address)
@@ -46,15 +54,12 @@ 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.
*/
- ResetInfo *current = 0;
+ save_psw = *reset_psw;
+ *reset_psw = (uint64_t) &jump_to_IPL_2;
+ *reset_psw |= RESET_PSW_MASK;
+ ipl_continue = address;
- save = *current;
-
- current->ipl_psw = (uint64_t) &jump_to_IPL_2;
- current->ipl_psw |= RESET_PSW_MASK;
- current->ipl_continue = address & PSW_MASK_SHORT_ADDR;
-
- debug_print_int("set IPL addr to", current->ipl_continue);
+ debug_print_int("set IPL addr to", ipl_continue);
/* Ensure the guest output starts fresh */
sclp_print("\n");
@@ -84,7 +89,12 @@ 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 */
@@ -78,6 +78,7 @@ 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);
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> --- pc-bios/s390-ccw/bootmap.c | 1 + pc-bios/s390-ccw/jump2ipl.c | 48 ++++++++++++++++++++++--------------- pc-bios/s390-ccw/s390-ccw.h | 1 + 3 files changed, 31 insertions(+), 19 deletions(-)