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authorLinus Torvalds <torvalds@linux-foundation.org>2017-05-05 11:36:44 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-05-05 11:36:44 -0700
commit7246f60068840847bdcf595be5f0b5ca632736e0 (patch)
treefd9a963a03c2655f3ba9d1ced3c87a2775f5b166 /arch/powerpc/kernel/idle_book3s.S
parente579dde654fc2c6b0d3e4b77a9a4b2d2405c510e (diff)
parent700b7eadd5625d22b8235fb21259b3d7d564c000 (diff)
Merge tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman: "Highlights include: - Larger virtual address space on 64-bit server CPUs. By default we use a 128TB virtual address space, but a process can request access to the full 512TB by passing a hint to mmap(). - Support for the new Power9 "XIVE" interrupt controller. - TLB flushing optimisations for the radix MMU on Power9. - Support for CAPI cards on Power9, using the "Coherent Accelerator Interface Architecture 2.0". - The ability to configure the mmap randomisation limits at build and runtime. - Several small fixes and cleanups to the kprobes code, as well as support for KPROBES_ON_FTRACE. - Major improvements to handling of system reset interrupts, correctly treating them as NMIs, giving them a dedicated stack and using a new hypervisor call to trigger them, all of which should aid debugging and robustness. - Many fixes and other minor enhancements. Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual, Anton Blanchard, Balbir Singh, Ben Hutchings, Benjamin Herrenschmidt, Bhupesh Sharma, Chris Packham, Christian Zigotzky, Christophe Leroy, Christophe Lombard, Daniel Axtens, David Gibson, Gautham R. Shenoy, Gavin Shan, Geert Uytterhoeven, Guilherme G. Piccoli, Hamish Martin, Hari Bathini, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mahesh J Salgaonkar, Mahesh Salgaonkar, Masami Hiramatsu, Matt Brown, Matthew R. Ochs, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Pan Xinhui, Paul Mackerras, Rashmica Gupta, Russell Currey, Sukadev Bhattiprolu, Thadeu Lima de Souza Cascardo, Tobin C. Harding, Tyrel Datwyler, Uma Krishnan, Vaibhav Jain, Vipin K Parashar, Yang Shi" * tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (214 commits) powerpc/64s: Power9 has no LPCR[VRMASD] field so don't set it powerpc/powernv: Fix TCE kill on NVLink2 powerpc/mm/radix: Drop support for CPUs without lockless tlbie powerpc/book3s/mce: Move add_taint() later in virtual mode powerpc/sysfs: Move #ifdef CONFIG_HOTPLUG_CPU out of the function body powerpc/smp: Document irq enable/disable after migrating IRQs powerpc/mpc52xx: Don't select user-visible RTAS_PROC powerpc/powernv: Document cxl dependency on special case in pnv_eeh_reset() powerpc/eeh: Clean up and document event handling functions powerpc/eeh: Avoid use after free in eeh_handle_special_event() cxl: Mask slice error interrupts after first occurrence cxl: Route eeh events to all drivers in cxl_pci_error_detected() cxl: Force context lock during EEH flow powerpc/64: Allow CONFIG_RELOCATABLE if COMPILE_TEST powerpc/xmon: Teach xmon oops about radix vectors powerpc/mm/hash: Fix off-by-one in comment about kernel contexts ids powerpc/pseries: Enable VFIO powerpc/powernv: Fix iommu table size calculation hook for small tables powerpc/powernv: Check kzalloc() return value in pnv_pci_table_alloc powerpc: Add arch/powerpc/tools directory ...
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