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Diffstat (limited to 'arch/powerpc/kernel/idle_book3s.S')
-rw-r--r--arch/powerpc/kernel/idle_book3s.S285
1 files changed, 225 insertions, 60 deletions
diff --git a/arch/powerpc/kernel/idle_book3s.S b/arch/powerpc/kernel/idle_book3s.S
index 6fd08219248d..07d4e0ad60db 100644
--- a/arch/powerpc/kernel/idle_book3s.S
+++ b/arch/powerpc/kernel/idle_book3s.S
@@ -20,6 +20,7 @@
#include <asm/kvm_book3s_asm.h>
#include <asm/opal.h>
#include <asm/cpuidle.h>
+#include <asm/exception-64s.h>
#include <asm/book3s/64/mmu-hash.h>
#include <asm/mmu.h>
@@ -94,12 +95,12 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_300)
core_idle_lock_held:
HMT_LOW
3: lwz r15,0(r14)
- andi. r15,r15,PNV_CORE_IDLE_LOCK_BIT
+ andis. r15,r15,PNV_CORE_IDLE_LOCK_BIT@h
bne 3b
HMT_MEDIUM
lwarx r15,0,r14
- andi. r9,r15,PNV_CORE_IDLE_LOCK_BIT
- bne core_idle_lock_held
+ andis. r9,r15,PNV_CORE_IDLE_LOCK_BIT@h
+ bne- core_idle_lock_held
blr
/*
@@ -113,7 +114,7 @@ core_idle_lock_held:
*
* Address to 'rfid' to in r5
*/
-_GLOBAL(pnv_powersave_common)
+pnv_powersave_common:
/* Use r3 to pass state nap/sleep/winkle */
/* NAP is a state loss, we create a regs frame on the
* stack, fill it up with the state we care about and
@@ -188,8 +189,8 @@ pnv_enter_arch207_idle_mode:
/* The following store to HSTATE_HWTHREAD_STATE(r13) */
/* MUST occur in real mode, i.e. with the MMU off, */
/* and the MMU must stay off until we clear this flag */
- /* and test HSTATE_HWTHREAD_REQ(r13) in the system */
- /* reset interrupt vector in exceptions-64s.S. */
+ /* and test HSTATE_HWTHREAD_REQ(r13) in */
+ /* pnv_powersave_wakeup in this file. */
/* The reason is that another thread can switch the */
/* MMU to a guest context whenever this flag is set */
/* to KVM_HWTHREAD_IN_IDLE, and if the MMU was on, */
@@ -209,15 +210,20 @@ pnv_enter_arch207_idle_mode:
/* Sleep or winkle */
lbz r7,PACA_THREAD_MASK(r13)
ld r14,PACA_CORE_IDLE_STATE_PTR(r13)
+ li r5,0
+ beq cr3,3f
+ lis r5,PNV_CORE_IDLE_WINKLE_COUNT@h
+3:
lwarx_loop1:
lwarx r15,0,r14
- andi. r9,r15,PNV_CORE_IDLE_LOCK_BIT
- bnel core_idle_lock_held
+ andis. r9,r15,PNV_CORE_IDLE_LOCK_BIT@h
+ bnel- core_idle_lock_held
+ add r15,r15,r5 /* Add if winkle */
andc r15,r15,r7 /* Clear thread bit */
- andi. r15,r15,PNV_CORE_IDLE_THREAD_BITS
+ andi. r9,r15,PNV_CORE_IDLE_THREAD_BITS
/*
* If cr0 = 0, then current thread is the last thread of the core entering
@@ -240,7 +246,7 @@ common_enter: /* common code for all the threads entering sleep or winkle */
IDLE_STATE_ENTER_SEQ_NORET(PPC_SLEEP)
fastsleep_workaround_at_entry:
- ori r15,r15,PNV_CORE_IDLE_LOCK_BIT
+ oris r15,r15,PNV_CORE_IDLE_LOCK_BIT@h
stwcx. r15,0,r14
bne- lwarx_loop1
isync
@@ -250,10 +256,10 @@ fastsleep_workaround_at_entry:
li r4,1
bl opal_config_cpu_idle_state
- /* Clear Lock bit */
- li r0,0
+ /* Unlock */
+ xoris r15,r15,PNV_CORE_IDLE_LOCK_BIT@h
lwsync
- stw r0,0(r14)
+ stw r15,0(r14)
b common_enter
enter_winkle:
@@ -301,8 +307,8 @@ power_enter_stop:
lwarx_loop_stop:
lwarx r15,0,r14
- andi. r9,r15,PNV_CORE_IDLE_LOCK_BIT
- bnel core_idle_lock_held
+ andis. r9,r15,PNV_CORE_IDLE_LOCK_BIT@h
+ bnel- core_idle_lock_held
andc r15,r15,r7 /* Clear thread bit */
stwcx. r15,0,r14
@@ -375,17 +381,113 @@ _GLOBAL(power9_idle_stop)
li r4,1
b pnv_powersave_common
/* No return */
+
/*
- * Called from reset vector. Check whether we have woken up with
- * hypervisor state loss. If yes, restore hypervisor state and return
- * back to reset vector.
+ * On waking up from stop 0,1,2 with ESL=1 on POWER9 DD1,
+ * HSPRG0 will be set to the HSPRG0 value of one of the
+ * threads in this core. Thus the value we have in r13
+ * may not be this thread's paca pointer.
+ *
+ * Fortunately, the TIR remains invariant. Since this thread's
+ * paca pointer is recorded in all its sibling's paca, we can
+ * correctly recover this thread's paca pointer if we
+ * know the index of this thread in the core.
+ *
+ * This index can be obtained from the TIR.
*
- * r13 - Contents of HSPRG0
+ * i.e, thread's position in the core = TIR.
+ * If this value is i, then this thread's paca is
+ * paca->thread_sibling_pacas[i].
+ */
+power9_dd1_recover_paca:
+ mfspr r4, SPRN_TIR
+ /*
+ * Since each entry in thread_sibling_pacas is 8 bytes
+ * we need to left-shift by 3 bits. Thus r4 = i * 8
+ */
+ sldi r4, r4, 3
+ /* Get &paca->thread_sibling_pacas[0] in r5 */
+ ld r5, PACA_SIBLING_PACA_PTRS(r13)
+ /* Load paca->thread_sibling_pacas[i] into r13 */
+ ldx r13, r4, r5
+ SET_PACA(r13)
+ /*
+ * Indicate that we have lost NVGPR state
+ * which needs to be restored from the stack.
+ */
+ li r3, 1
+ stb r0,PACA_NAPSTATELOST(r13)
+ blr
+
+/*
+ * Called from machine check handler for powersave wakeups.
+ * Low level machine check processing has already been done. Now just
+ * go through the wake up path to get everything in order.
+ *
+ * r3 - The original SRR1 value.
+ * Original SRR[01] have been clobbered.
+ * MSR_RI is clear.
+ */
+.global pnv_powersave_wakeup_mce
+pnv_powersave_wakeup_mce:
+ /* Set cr3 for pnv_powersave_wakeup */
+ rlwinm r11,r3,47-31,30,31
+ cmpwi cr3,r11,2
+
+ /*
+ * Now put the original SRR1 with SRR1_WAKEMCE_RESVD as the wake
+ * reason into SRR1, which allows reuse of the system reset wakeup
+ * code without being mistaken for another type of wakeup.
+ */
+ oris r3,r3,SRR1_WAKEMCE_RESVD@h
+ mtspr SPRN_SRR1,r3
+
+ b pnv_powersave_wakeup
+
+/*
+ * Called from reset vector for powersave wakeups.
* cr3 - set to gt if waking up with partial/complete hypervisor state loss
*/
-_GLOBAL(pnv_restore_hyp_resource)
+.global pnv_powersave_wakeup
+pnv_powersave_wakeup:
+ ld r2, PACATOC(r13)
+
BEGIN_FTR_SECTION
- ld r2,PACATOC(r13);
+BEGIN_FTR_SECTION_NESTED(70)
+ bl power9_dd1_recover_paca
+END_FTR_SECTION_NESTED_IFSET(CPU_FTR_POWER9_DD1, 70)
+ bl pnv_restore_hyp_resource_arch300
+FTR_SECTION_ELSE
+ bl pnv_restore_hyp_resource_arch207
+ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_300)
+
+ li r0,PNV_THREAD_RUNNING
+ stb r0,PACA_THREAD_IDLE_STATE(r13) /* Clear thread state */
+
+#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+ li r0,KVM_HWTHREAD_IN_KERNEL
+ stb r0,HSTATE_HWTHREAD_STATE(r13)
+ /* Order setting hwthread_state vs. testing hwthread_req */
+ sync
+ lbz r0,HSTATE_HWTHREAD_REQ(r13)
+ cmpwi r0,0
+ beq 1f
+ b kvm_start_guest
+1:
+#endif
+
+ /* Return SRR1 from power7_nap() */
+ mfspr r3,SPRN_SRR1
+ blt cr3,pnv_wakeup_noloss
+ b pnv_wakeup_loss
+
+/*
+ * Check whether we have woken up with hypervisor state loss.
+ * If yes, restore hypervisor state and return back to link.
+ *
+ * cr3 - set to gt if waking up with partial/complete hypervisor state loss
+ */
+pnv_restore_hyp_resource_arch300:
/*
* POWER ISA 3. Use PSSCR to determine if we
* are waking up from deep idle state
@@ -400,31 +502,19 @@ BEGIN_FTR_SECTION
*/
rldicl r5,r5,4,60
cmpd cr4,r5,r4
- bge cr4,pnv_wakeup_tb_loss
- /*
- * Waking up without hypervisor state loss. Return to
- * reset vector
- */
- blr
+ bge cr4,pnv_wakeup_tb_loss /* returns to caller */
-END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
+ blr /* Waking up without hypervisor state loss. */
+/* Same calling convention as arch300 */
+pnv_restore_hyp_resource_arch207:
/*
* POWER ISA 2.07 or less.
- * Check if last bit of HSPGR0 is set. This indicates whether we are
- * waking up from winkle.
+ * Check if we slept with sleep or winkle.
*/
- clrldi r5,r13,63
- clrrdi r13,r13,1
-
- /* Now that we are sure r13 is corrected, load TOC */
- ld r2,PACATOC(r13);
- cmpwi cr4,r5,1
- mtspr SPRN_HSPRG0,r13
-
- lbz r0,PACA_THREAD_IDLE_STATE(r13)
- cmpwi cr2,r0,PNV_THREAD_NAP
- bgt cr2,pnv_wakeup_tb_loss /* Either sleep or Winkle */
+ lbz r4,PACA_THREAD_IDLE_STATE(r13)
+ cmpwi cr2,r4,PNV_THREAD_NAP
+ bgt cr2,pnv_wakeup_tb_loss /* Either sleep or Winkle */
/*
* We fall through here if PACA_THREAD_IDLE_STATE shows we are waking
@@ -433,8 +523,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
*/
bgt cr3,.
- blr /* Return back to System Reset vector from where
- pnv_restore_hyp_resource was invoked */
+ blr /* Waking up without hypervisor state loss */
/*
* Called if waking up from idle state which can cause either partial or
@@ -444,9 +533,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
*
* r13 - PACA
* cr3 - gt if waking up with partial/complete hypervisor state loss
+ *
+ * If ISA300:
* cr4 - gt or eq if waking up from complete hypervisor state loss.
+ *
+ * If ISA207:
+ * r4 - PACA_THREAD_IDLE_STATE
*/
-_GLOBAL(pnv_wakeup_tb_loss)
+pnv_wakeup_tb_loss:
ld r1,PACAR1(r13)
/*
* Before entering any idle state, the NVGPRs are saved in the stack.
@@ -473,18 +567,19 @@ _GLOBAL(pnv_wakeup_tb_loss)
* is required to return back to reset vector after hypervisor state
* restore is complete.
*/
+ mr r18,r4
mflr r17
mfspr r16,SPRN_SRR1
BEGIN_FTR_SECTION
CHECK_HMI_INTERRUPT
END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
- lbz r7,PACA_THREAD_MASK(r13)
ld r14,PACA_CORE_IDLE_STATE_PTR(r13)
-lwarx_loop2:
- lwarx r15,0,r14
- andi. r9,r15,PNV_CORE_IDLE_LOCK_BIT
+ lbz r7,PACA_THREAD_MASK(r13)
+
/*
+ * Take the core lock to synchronize against other threads.
+ *
* Lock bit is set in one of the 2 cases-
* a. In the sleep/winkle enter path, the last thread is executing
* fastsleep workaround code.
@@ -492,23 +587,93 @@ lwarx_loop2:
* workaround undo code or resyncing timebase or restoring context
* In either case loop until the lock bit is cleared.
*/
- bnel core_idle_lock_held
+1:
+ lwarx r15,0,r14
+ andis. r9,r15,PNV_CORE_IDLE_LOCK_BIT@h
+ bnel- core_idle_lock_held
+ oris r15,r15,PNV_CORE_IDLE_LOCK_BIT@h
+ stwcx. r15,0,r14
+ bne- 1b
+ isync
- cmpwi cr2,r15,0
+ andi. r9,r15,PNV_CORE_IDLE_THREAD_BITS
+ cmpwi cr2,r9,0
/*
* At this stage
* cr2 - eq if first thread to wakeup in core
* cr3- gt if waking up with partial/complete hypervisor state loss
+ * ISA300:
* cr4 - gt or eq if waking up from complete hypervisor state loss.
*/
- ori r15,r15,PNV_CORE_IDLE_LOCK_BIT
- stwcx. r15,0,r14
- bne- lwarx_loop2
- isync
-
BEGIN_FTR_SECTION
+ /*
+ * Were we in winkle?
+ * If yes, check if all threads were in winkle, decrement our
+ * winkle count, set all thread winkle bits if all were in winkle.
+ * Check if our thread has a winkle bit set, and set cr4 accordingly
+ * (to match ISA300, above). Pseudo-code for core idle state
+ * transitions for ISA207 is as follows (everything happens atomically
+ * due to store conditional and/or lock bit):
+ *
+ * nap_idle() { }
+ * nap_wake() { }
+ *
+ * sleep_idle()
+ * {
+ * core_idle_state &= ~thread_in_core
+ * }
+ *
+ * sleep_wake()
+ * {
+ * bool first_in_core, first_in_subcore;
+ *
+ * first_in_core = (core_idle_state & IDLE_THREAD_BITS) == 0;
+ * first_in_subcore = (core_idle_state & SUBCORE_SIBLING_MASK) == 0;
+ *
+ * core_idle_state |= thread_in_core;
+ * }
+ *
+ * winkle_idle()
+ * {
+ * core_idle_state &= ~thread_in_core;
+ * core_idle_state += 1 << WINKLE_COUNT_SHIFT;
+ * }
+ *
+ * winkle_wake()
+ * {
+ * bool first_in_core, first_in_subcore, winkle_state_lost;
+ *
+ * first_in_core = (core_idle_state & IDLE_THREAD_BITS) == 0;
+ * first_in_subcore = (core_idle_state & SUBCORE_SIBLING_MASK) == 0;
+ *
+ * core_idle_state |= thread_in_core;
+ *
+ * if ((core_idle_state & WINKLE_MASK) == (8 << WINKLE_COUNT_SIHFT))
+ * core_idle_state |= THREAD_WINKLE_BITS;
+ * core_idle_state -= 1 << WINKLE_COUNT_SHIFT;
+ *
+ * winkle_state_lost = core_idle_state &
+ * (thread_in_core << WINKLE_THREAD_SHIFT);
+ * core_idle_state &= ~(thread_in_core << WINKLE_THREAD_SHIFT);
+ * }
+ *
+ */
+ cmpwi r18,PNV_THREAD_WINKLE
+ bne 2f
+ andis. r9,r15,PNV_CORE_IDLE_WINKLE_COUNT_ALL_BIT@h
+ subis r15,r15,PNV_CORE_IDLE_WINKLE_COUNT@h
+ beq 2f
+ ori r15,r15,PNV_CORE_IDLE_THREAD_WINKLE_BITS /* all were winkle */
+2:
+ /* Shift thread bit to winkle mask, then test if this thread is set,
+ * and remove it from the winkle bits */
+ slwi r8,r7,8
+ and r8,r8,r15
+ andc r15,r15,r8
+ cmpwi cr4,r8,1 /* cr4 will be gt if our bit is set, lt if not */
+
lbz r4,PACA_SUBCORE_SIBLING_MASK(r13)
and r4,r4,r15
cmpwi r4,0 /* Check if first in subcore */
@@ -593,7 +758,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
mtspr SPRN_WORC,r4
clear_lock:
- andi. r15,r15,PNV_CORE_IDLE_THREAD_BITS
+ xoris r15,r15,PNV_CORE_IDLE_LOCK_BIT@h
lwsync
stw r15,0(r14)
@@ -651,8 +816,7 @@ hypervisor_state_restored:
mtspr SPRN_SRR1,r16
mtlr r17
- blr /* Return back to System Reset vector from where
- pnv_restore_hyp_resource was invoked */
+ blr /* return to pnv_powersave_wakeup */
fastsleep_workaround_at_exit:
li r3,1
@@ -664,7 +828,8 @@ fastsleep_workaround_at_exit:
* R3 here contains the value that will be returned to the caller
* of power7_nap.
*/
-_GLOBAL(pnv_wakeup_loss)
+.global pnv_wakeup_loss
+pnv_wakeup_loss:
ld r1,PACAR1(r13)
BEGIN_FTR_SECTION
CHECK_HMI_INTERRUPT
@@ -684,7 +849,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
* R3 here contains the value that will be returned to the caller
* of power7_nap.
*/
-_GLOBAL(pnv_wakeup_noloss)
+pnv_wakeup_noloss:
lbz r0,PACA_NAPSTATELOST(r13)
cmpwi r0,0
bne pnv_wakeup_loss