haraldwolff/qemu-patch-raspberry4
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pc-bios: s390x: Use reset PSW if avaliable

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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>
This commit is contained in:
Janosch Frank 2020-10-06 05:42:48 -04:00 committed by Thomas Huth
parent 26e0b96fa9
commit 42ab98e7d7
3 changed files with 24 additions and 9 deletions
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6
pc-bios/s390-ccw/bootmap.c
View file

@ -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)

26
pc-bios/s390-ccw/jump2ipl.c
View file

@ -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 */

1
pc-bios/s390-ccw/s390-ccw.h
View file

@ -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);