| Message ID | 20201006094249.50640-4-frankja@linux.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | pc-bios: s390x: Cleanup part 2 | expand |
On 06/10/2020 11.42, Janosch Frank wrote: > 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> > --- > pc-bios/s390-ccw/bootmap.c | 6 ++++-- > pc-bios/s390-ccw/jump2ipl.c | 26 +++++++++++++++++++------- > pc-bios/s390-ccw/s390-ccw.h | 1 + > 3 files changed, 24 insertions(+), 9 deletions(-) > > diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c > index 8747c4ea26..88bd12d5d7 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) > @@ -515,7 +516,8 @@ 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..63afa4a349 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 ? address : *reset_psw & PSW_MASK_SHORT_ADDR); checkpatch.pl complains about a very long line here... I'll change this line to use the Elvis operator, so that is a little bit short, ok? Thomas
diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c index 8747c4ea26..88bd12d5d7 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) @@ -515,7 +516,8 @@ 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..63afa4a349 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 ? 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 36b884cced..7090720422 100644 --- a/pc-bios/s390-ccw/s390-ccw.h +++ b/pc-bios/s390-ccw/s390-ccw.h @@ -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);