On 05.11.19 17:28, Janosch Frank wrote:
In the subject "Disable" vs. "Remove" ?
On a diag308 subcode 0 CRs will be reset, so we need to mask of PSW
DAT indication until we restore our CRs.
Also we need to set the short psw indication to be compliant with the
architecture.
Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
---
lib/s390x/asm-offsets.c | 1 +
lib/s390x/asm/arch_def.h | 3 ++-
s390x/cstart64.S | 20 ++++++++++++++------
3 files changed, 17 insertions(+), 7 deletions(-)
diff --git a/lib/s390x/asm-offsets.c b/lib/s390x/asm-offsets.c
index 4b213f8..61d2658 100644
--- a/lib/s390x/asm-offsets.c
+++ b/lib/s390x/asm-offsets.c
@@ -58,6 +58,7 @@ int main(void)
OFFSET(GEN_LC_SW_INT_FPRS, lowcore, sw_int_fprs);
OFFSET(GEN_LC_SW_INT_FPC, lowcore, sw_int_fpc);
OFFSET(GEN_LC_SW_INT_CRS, lowcore, sw_int_crs);
+ OFFSET(GEN_LC_SW_INT_PSW, lowcore, sw_int_psw);
OFFSET(GEN_LC_MCCK_EXT_SA_ADDR, lowcore, mcck_ext_sa_addr);
OFFSET(GEN_LC_FPRS_SA, lowcore, fprs_sa);
OFFSET(GEN_LC_GRS_SA, lowcore, grs_sa);
diff --git a/lib/s390x/asm/arch_def.h b/lib/s390x/asm/arch_def.h
index 07d4e5e..7d25e4f 100644
--- a/lib/s390x/asm/arch_def.h
+++ b/lib/s390x/asm/arch_def.h
@@ -79,7 +79,8 @@ struct lowcore {
uint32_t sw_int_fpc; /* 0x0300 */
uint8_t pad_0x0304[0x0308 - 0x0304]; /* 0x0304 */
uint64_t sw_int_crs[16]; /* 0x0308 */
- uint8_t pad_0x0310[0x11b0 - 0x0388]; /* 0x0388 */
+ struct psw sw_int_psw; /* 0x0388 */
+ uint8_t pad_0x0310[0x11b0 - 0x0390]; /* 0x0390 */
uint64_t mcck_ext_sa_addr; /* 0x11b0 */
uint8_t pad_0x11b8[0x1200 - 0x11b8]; /* 0x11b8 */
uint64_t fprs_sa[16]; /* 0x1200 */
diff --git a/s390x/cstart64.S b/s390x/cstart64.S
index 0455591..2e0dcf5 100644
--- a/s390x/cstart64.S
+++ b/s390x/cstart64.S
@@ -129,8 +129,15 @@ memsetxc:
.globl diag308_load_reset
diag308_load_reset:
SAVE_REGS
- /* Save the first PSW word to the IPL PSW */
+ /* Backup current PSW */
/*
* Backup the current PSW MASK, as we have to restore it on
* success.
*/
epsw %r0, %r1
+ st %r0, GEN_LC_SW_INT_PSW
+ st %r1, GEN_LC_SW_INT_PSW + 4
I was confused at first, but then I realized that you really only store
the PSW mask here and not also the PSW address ...
+ /* Disable DAT as the CRs will be reset too */
+ nilh %r0, 0xfbff
+ /* Add psw bit 12 to indicate short psw */
+ oilh %r0, 0x0008
Why care about the old PSW mask here at all? Wouldn't it be easier to
just construct a new PSW mask from scratch? (64bit, PSW bit 12 set ...)
Save it somewhere and just load it directly from memory.
+ /* Save the first PSW word to the IPL PSW */
st %r0, 0
/* Store the address and the bit for 31 bit addressing */
larl %r0, 0f
@@ -142,12 +149,13 @@ diag308_load_reset:
xgr %r2, %r2
br %r14
/* Success path */
- /* We lost cr0 due to the reset */
-0: larl %r1, initial_cr0
- lctlg %c0, %c0, 0(%r1)
- RESTORE_REGS
+ /* Switch to z/Architecture mode and 64-bit */
+0: RESTORE_REGS
lhi %r2, 1
- br %r14
+ larl %r0, 1f
+ stg %r0, GEN_LC_SW_INT_PSW + 8
+ lpswe GEN_LC_SW_INT_PSW
+1: br %r14
.globl smp_cpu_setup_state
smp_cpu_setup_state:
--
Thanks,
David / dhildenb
